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Limonene, (+/-)-

PubChem CID
22311
Structure
Limonene, (+/-)-_small.png
Limonene, (+/-)-_3D_Structure.png
Molecular Formula
Synonyms
  • LIMONENE
  • Dipentene
  • 138-86-3
  • Cinene
  • Cajeputene
Molecular Weight
136.23 g/mol
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Dates
  • Create:
    2004-09-16
  • Modify:
    2025-01-04
Description
Dipentene appears as a colorless liquid with an odor of lemon. Flash point 113 °F. Density about 7.2 lb /gal and insoluble in water. Hence floats on water. Vapors heavier than air. Used as a solvent for rosin, waxes, rubber; as a dispersing agent for oils, resins, paints, lacquers, varnishes, and in floor waxes and furniture polishes.
Limonene is a monoterpene that is cyclohex-1-ene substituted by a methyl group at position 1 and a prop-1-en-2-yl group at position 4 respectively. It has a role as a human metabolite. It is a cycloalkene and a p-menthadiene.
Limonene has been reported in Camellia sinensis, Hypericum foliosum, and other organisms with data available.

1 Structures

1.1 2D Structure

Chemical Structure Depiction
Limonene, (+/-)-.png

1.2 3D Conformer

2 Names and Identifiers

2.1 Computed Descriptors

2.1.1 IUPAC Name

1-methyl-4-prop-1-en-2-ylcyclohexene
Computed by Lexichem TK 2.7.0 (PubChem release 2021.10.14)

2.1.2 InChI

InChI=1S/C10H16/c1-8(2)10-6-4-9(3)5-7-10/h4,10H,1,5-7H2,2-3H3
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.3 InChIKey

XMGQYMWWDOXHJM-UHFFFAOYSA-N
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.4 SMILES

CC1=CCC(CC1)C(=C)C
Computed by OEChem 2.3.0 (PubChem release 2024.12.12)

2.2 Molecular Formula

C10H16
Computed by PubChem 2.2 (PubChem release 2021.10.14)

2.3 Other Identifiers

2.3.1 CAS

138-86-3
5989-27-5
7705-14-8
8016-20-4
9003-73-0

2.3.3 Deprecated CAS

555-08-8, 7705-14-8, 8022-90-0, 8050-32-6
7705-14-8

2.3.4 European Community (EC) Number

2.3.5 UNII

2.3.6 UN Number

2.3.7 ChEBI ID

2.3.8 ChEMBL ID

2.3.9 DSSTox Substance ID

2.3.10 HMDB ID

2.3.11 KEGG ID

2.3.12 Metabolomics Workbench ID

2.3.13 NCI Thesaurus Code

2.3.14 Nikkaji Number

2.3.15 NSC Number

2.3.16 RXCUI

2.3.17 Wikidata

2.3.18 Wikipedia

2.4 Synonyms

2.4.1 MeSH Entry Terms

  • (+)-(R)-4-isopropenyl-1-methylcyclohexene
  • (+)-limonene
  • (-)-limonene
  • (4R)-1-methyl-4-(1-methylethenyl)cyclohexene
  • (4S)-1-methyl-4-isopropenylcyclohex-1-ene
  • (D)-limonene
  • (R)-(+)-limonene
  • (R)-4-isopropenyl-1-methylcyclohexene
  • 1-methyl-4-(1-methylethenyl)cyclohexene
  • 4 Mentha 1,8 diene
  • 4-mentha-1,8-diene
  • AISA 5203-L (+)limonene
  • cyclohexene, 1-methyl-4-(1-methylethenyl)-, (4R)-
  • d Limonene
  • d-limonene
  • dipentene
  • limonene
  • limonene, (+)-
  • limonene, (+-)-
  • limonene, (+-)-isomer
  • limonene, (R)-isomer
  • limonene, (S)-isomer

2.4.2 Depositor-Supplied Synonyms

3 Chemical and Physical Properties

3.1 Computed Properties

Property Name
Molecular Weight
Property Value
136.23 g/mol
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
XLogP3-AA
Property Value
3.4
Reference
Computed by XLogP3 3.0 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Donor Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Acceptor Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Rotatable Bond Count
Property Value
1
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Exact Mass
Property Value
136.125200510 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Monoisotopic Mass
Property Value
136.125200510 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Topological Polar Surface Area
Property Value
0Ų
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Heavy Atom Count
Property Value
10
Reference
Computed by PubChem
Property Name
Formal Charge
Property Value
0
Reference
Computed by PubChem
Property Name
Complexity
Property Value
163
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Isotope Atom Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Atom Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Atom Stereocenter Count
Property Value
1
Reference
Computed by PubChem
Property Name
Defined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Covalently-Bonded Unit Count
Property Value
1
Reference
Computed by PubChem
Property Name
Compound Is Canonicalized
Property Value
Yes
Reference
Computed by PubChem (release 2021.10.14)

3.2 Experimental Properties

3.2.1 Physical Description

Dipentene appears as a colorless liquid with an odor of lemon. Flash point 113 °F. Density about 7.2 lb /gal and insoluble in water. Hence floats on water. Vapors heavier than air. Used as a solvent for rosin, waxes, rubber; as a dispersing agent for oils, resins, paints, lacquers, varnishes, and in floor waxes and furniture polishes.
Liquid
Colorless liquid with a citrus-like odor; [ChemIDplus]
A colorless liquid with an odor of lemon.

3.2.2 Color / Form

Colorless liquid
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 757
Colorless mobile liquid
Opdyke, D.L.J. (ed.). Monographs on Fragrance Raw Materials. New York: Pergamon Press, 1979., p. 333
Clear to light yellow liquid
USEPA/OPPTS; R.E.D. Limonene (138-86-3). Reregistration Eligibility Decisions (REDs) Database. EPA-738-R-94-030. Sept 1994. Available from, as of Apr 24, 2015: https://www.epa.gov/pesticides/reregistration/status.htm

3.2.3 Odor

Pleasant lemon-like
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 102

3.2.4 Taste

Sweet, citrus taste
Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Volume 2. Boca Raton, Florida: CRC Press, Inc., 1980., p. 283

3.2.5 Boiling Point

352 °F at 760 mmHg (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
Colorless liquid; lemon-like odor. Specific gravity: 0.857 at 15.5 °C/15.5 °C; BP: 175-176 °C; Refractive index: 1.473 at 20 °C. Miscible with alcohol; insoluble in water /Limonene, inactive/
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 462
352 °F

3.2.6 Melting Point

-40 °F (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
-95.5 °C
Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. V3: 2306
-40 °F

3.2.7 Flash Point

115 °F (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
45 °C
113 °F (45 °C) (Close cup)
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-53
115 °F

3.2.8 Solubility

In water, 7.57 mg/L at 25 °C
Miller DJ, Hawthorne SB; J Chem Eng Data 44: 315-8 (2000)
Miscible with alcohol
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021
Miscible with alcohol, ether.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V4: 2827

3.2.9 Density

0.842 at 69.8 °F (USCG, 1999) - Less dense than water; will float
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
0.8402 at 20.85 °C/4 °C
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021
0.842 at 69.8 °F

3.2.10 Vapor Density

4.7 (Air = 1)
Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997., p. 325-45

3.2.11 Vapor Pressure

1.55 [mmHg]
1.55 mm Hg at 25 °C /extrapolated/
Boublik, T., Fried, V., and Hala, E., The Vapour Pressures of Pure Substances. Second Revised Edition. Amsterdam: Elsevier, 1984.

3.2.12 LogP

log Kow = 4.57
Li J, Perdue EM; Physicochemical properties of selected monoterpenes. Preprints of papers presented at the 209th ACS National Meeting Anaheim, CA April 2-7, 35(1): 134-7 (1995)

3.2.13 Autoignition Temperature

458 °F (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
458 °F (237 °C)
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-53

3.2.14 Decomposition

When heated to decomposition it emits acrid smoke and irritating fumes.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2295

3.2.15 Heat of Combustion

-19,520 Btu/lb = -10,840 cal/g = -454X10+5 J/kg
U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.

3.2.16 Heat of Vaporization

140 Btu/lb = 77 cal/g = 3.2x10+5 J/kg
U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.

3.2.17 Surface Tension

26 dynes/cm = 0.026 N/m at 20 °C
U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.

3.2.18 Refractive Index

Index of refraction: 1.4744 at 25 °C/D
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021

3.2.19 Kovats Retention Index

Standard non-polar
1020, 1020, 1022, 1028, 1023, 1020, 1022, 1022, 1005, 1054, 1026, 1029, 1021, 1053, 1020, 1020, 1024, 1021, 1025, 1016, 1022, 1019, 1064, 1020, 1020, 1058, 1039, 1030, 1020, 1012, 1025, 1025, 1026, 1022, 1022, 1017, 1032, 1017, 1019, 1018, 1021, 1020, 1020, 1018, 1029, 1022, 1020, 1024, 1020, 1020, 1012, 1022, 1020, 1031, 1021, 1023, 1023, 1019, 1010, 1020, 1022, 1020, 1025, 1025, 1013, 1020, 1020, 1019, 1033, 1013, 1015.8, 1015.8, 1020, 1026, 1026, 1021, 1019, 1018, 1023, 1023, 1021, 1031, 1023, 1023, 1025, 1025, 1025, 1023, 1030.8, 1038, 1030, 1021, 1021, 1025, 1016, 1016, 1022, 1020, 1020, 1015, 1028, 1023, 1021, 1021, 1023, 1026, 1024, 1033.2, 1021, 1021, 1020, 1019, 1026, 1018, 1021, 1031, 1026, 1027, 1025, 1021, 1030, 1015, 1031, 1032, 1026, 1022, 1023, 1022, 1018, 1025, 1023, 1032, 1023, 1020, 1023, 1026, 1019, 1035, 1029, 1030, 1020, 1027, 1022, 1019.5, 1021.5, 1024.9, 1026.3, 1031.9, 1026.3, 1030.73, 1026, 1033, 1034, 1017, 1021, 1026, 1029, 1030, 1031, 1031, 1034, 1017, 1018, 1032, 1032, 1022, 1011.1, 1013.66, 1016.32, 1018.99, 1021.74, 1024.53, 1027.41, 1030.32, 1033.31, 1036.39, 1039.52, 1022, 1022, 1020, 1023, 1017, 1017, 1024, 1041, 1025, 1033.04, 1033.21, 1039.19, 1039.68, 1024, 1024, 1025, 1024, 1039, 1017, 1019, 1018, 1031, 1024, 1019, 1016, 1015, 1025, 1024, 1024, 1024, 1024, 1021.75, 1024.42, 1027.23, 1030.21, 1033.38, 1036.74, 1040.32, 1044.15, 1023, 1018, 1020, 1014, 1028, 1025, 1021, 1019, 1024, 1024, 1026, 1025, 1024, 1027, 1026, 1030, 1043, 1020, 1020, 1024, 1025, 1028, 1026, 1027, 1027.1, 1026, 1029, 1025, 1019, 1020, 1025, 1021, 1026, 1020, 1027, 1030, 1022, 1038, 1020, 1020, 1030.5, 1020, 1020, 1030, 1030, 1036, 1040, 1045, 1049, 1040, 1019.8, 1026, 1029, 1032, 1036, 1019, 1036, 1023, 1038, 1018, 1018, 1029, 1030, 1053, 1027, 1031.3, 1035.2, 1030, 1031, 1023, 1024, 1051, 1042.8, 1043, 1028, 1009, 1025, 1022, 1022, 1025, 1025, 1026, 1026, 1017, 1033, 1031, 1032, 1033, 1032, 1025, 1020, 1021, 1025, 1026, 1054, 1024, 1021, 1021, 1024, 1020, 1018, 1020, 1027, 1018, 1035, 1018, 1025, 1028, 1031, 1025, 1023, 1009, 1009, 1021, 1023, 1020, 1020, 1016, 1015, 1022, 1020, 1025, 1027, 1015, 1009, 1024, 1029, 1035, 1022, 1022, 1030, 1022, 1026, 1009, 1016, 1026, 1009, 1024, 1032, 1030, 1018, 1031, 1026, 1020, 1019, 1028, 1029, 1029, 1014, 1024, 1009, 1048, 1025, 1020, 1020, 1022, 1015, 1021, 1023, 1018, 1018, 1020, 1021, 1021, 1021, 1009, 1019, 1029, 1024, 1024, 1020, 1023, 1032, 1021, 1030, 1031, 1028, 1024, 1029, 1023, 1031, 1029, 1038, 1012, 1019, 1017, 1020, 1016, 1009, 1025, 1034, 1027, 1024, 1035, 1029, 1009, 1020, 1009, 1020, 1014, 1017, 1030, 1024, 1030, 1026, 1026, 1025, 1029, 1029, 1029, 1013, 1027, 1025, 1012, 1016, 1020, 1017, 1029, 1023, 1039, 1026, 1028, 1014, 1017, 1017, 1029, 1025, 1025, 1025, 1009, 1030, 1024, 1026, 1022, 1015, 1015, 1017, 1020, 1020, 1024, 1024, 1013, 1033, 1033, 1023, 1020, 1021, 1024, 1039, 1020, 1025, 1031, 1009, 1024, 1021.1, 1017, 1019, 1028, 1015, 1032, 1020, 1021, 1033, 1022, 1019, 1027, 1006, 1021, 1021, 1008, 1040, 1041, 1027.1, 1034.1, 1017, 1015, 1016, 1022, 1022, 1022, 1022, 1024, 1020, 1024, 1024, 1010, 1030, 1028, 1024, 1028, 1030, 1020, 1014, 1024, 1022, 1020, 1012, 1016, 1025, 1022, 1019, 1024, 1009, 1019, 1023, 1025, 1024, 1021, 1019, 1020, 1020, 1020, 1020, 1015, 1026, 1029, 1030, 1030, 1021, 1028, 1016, 1015, 1029.1, 1009, 1030, 1013, 1014, 1018, 1027, 1031, 1023, 1024, 1009, 1025, 1026, 1021, 1026, 1027, 1022.1, 1021, 1020, 1026, 1024, 1033.7, 1012, 1024, 1025, 1018, 1020, 1015, 1022, 1009, 1026, 1030, 1024, 1030.3, 1022, 1009, 1020, 1022, 1025, 1021, 1028, 1025, 1025, 1009, 1026, 1018, 1018, 1031, 1025, 1021, 1022, 1009, 1021, 1028, 1021, 1021, 1027, 1029, 1017, 1017, 1017, 1009, 1009, 1024, 1023, 1038, 1039, 1009, 1025, 1030, 1029, 1019, 1009, 1033, 1022, 1020, 1022, 1024, 1025, 1031, 1019, 1024, 1021, 1020, 1021, 1020, 1020, 1024, 1025, 1026, 1026, 1023, 1020, 1020, 1027, 1020, 1019, 1030, 1030, 1039, 1025, 1022, 1024, 1012, 1029, 1023, 1030, 1019, 1024, 1029, 1019, 1020, 1020, 1027, 1028, 1022, 1029, 1032, 1014.4, 1020.3, 1020.3, 1021.1, 1021.4, 1020, 1021, 1020, 1020, 1020, 1019, 1020, 1029, 1024, 1027, 1030, 1022, 1019, 1014, 1020, 1020, 1030, 1020, 1021, 1032, 1019, 1019, 1020, 1019, 1019, 1019, 1016, 1019, 1020, 1013, 1019, 1018, 1030, 1031, 1019, 1053, 1021, 1022, 1024, 1008, 1020, 1002.4
Semi-standard non-polar
1028, 1035, 1033, 1033, 1028, 1029, 1032, 1035, 1033, 1039, 1032, 1033, 1032, 1030, 1033, 1015, 1030, 1034, 1035, 1035, 1037, 1028, 1029, 1027, 1028, 1030, 1031, 1031, 1032, 1027, 1032, 1028, 1028, 1020, 1025, 1025, 1039, 1035, 1060, 1025, 1025, 1025, 1025, 1037, 1027, 1032, 1021, 1029, 1031, 1033, 1030, 1028, 1025, 1027, 1031, 1028, 1030, 1030, 1018, 1033, 1007, 1025, 1032, 1031, 1030, 1029, 1029, 1042, 1018, 1025, 1026, 1019, 1038, 1027, 1032, 1039, 1032, 1035, 1035, 1032, 1032, 1026, 1040, 1030, 1031, 1032, 1027, 1015, 1029, 1025, 1031, 1029, 1028, 1031, 1028, 1030, 1034, 1034, 1021, 1028, 1047, 1031.4, 1032.5, 1033.2, 1028, 1026, 1025, 1028, 1025, 1032, 1035, 1035, 1035, 1032, 1027, 1029, 1032, 1032, 1032, 1036, 1032, 1034, 1027, 1031, 1027, 1027, 1028, 1028, 1031, 1031, 1030, 1030, 1035, 1030, 1028, 1028, 1031, 1033, 1012, 1030, 1033, 1038, 1034, 1029, 1029, 1033, 1033, 1032, 1032, 1032, 1029, 1039, 1032, 1033, 1032, 1033, 1033, 1032, 1033, 1032, 1036, 1029, 1027, 1029, 1030, 1035, 1030, 1033, 1025, 1032, 1030, 1031, 1031, 1030, 1030, 1028, 1027, 1032, 1029, 1030, 1021, 1037.3, 1033, 1030, 1039, 1027, 1038, 1040, 1037, 1025, 1032, 1032, 1033, 1029, 1025, 1028, 1031, 1025, 1021, 1024, 1031, 1029, 1030, 1034, 1031, 1005, 1022, 1031, 1031, 1029, 1032, 1032, 1034, 1029, 1017, 1035, 1027, 1030, 1030, 1026, 1030, 1027, 1027, 1020, 1014, 1029, 1031, 1039, 1040, 1030, 1027, 1039, 1030, 1022, 1023, 1028, 1028, 1025, 1028, 1026, 1018, 1020, 1032, 1038, 1033, 1033, 1021, 1021, 1020, 1020, 1025, 1031, 1025, 1031, 1036, 1038, 1029, 1029, 1040, 1025, 1028, 1037, 1055, 1034, 1029, 1031, 1029, 1029, 1031, 1028, 1030, 1044, 1035, 1033, 1010, 1031, 1018, 1018, 995, 1029, 1031, 1027, 1029, 1009, 1032, 1031, 995, 1029, 1029.7, 1029, 1020, 1032, 1030, 1032, 1036, 1024, 1025, 1029, 1027, 1029, 1044, 1014, 1032, 1031, 1031, 1039, 1031, 1030, 1031, 1032, 1028, 1033, 1031, 1031, 1034, 1034, 1028, 1031, 1031, 1031, 1031, 1033, 1033, 1030, 1031, 1032, 1035, 1032, 1031, 1033, 1033, 1030, 1031, 1025, 1021, 1028, 1028, 1028, 1031, 1027, 1028, 1020, 1029, 1030, 1020, 1030, 1024, 1030, 1030, 1034, 1023, 1048, 1044.9, 1021, 1028, 1031, 1036, 1026, 1029, 1028, 1029, 1029, 1032, 1032, 1025, 1031, 1030, 1034, 1031, 1033, 1028, 1030, 1024, 1024, 1029, 1038, 1025, 1030, 1029, 1029, 1030, 1030, 1037, 1028, 1032, 1029, 1029, 1031, 1031, 1030, 1029, 1032, 1049, 1030, 1028, 1032, 1031, 1032, 1025, 1025, 1024, 1032, 1033, 1032, 1033, 1031, 1032, 1026, 1030, 1030, 1030, 1029, 1036, 1030, 1030, 1034, 1030, 1033, 1034, 1029, 1030, 1028, 1022, 1033, 1030, 1032, 1040, 1031, 1032, 1029, 1028, 1007, 1030, 1029, 1028, 1034, 1029, 1033, 1028, 1035, 1034, 1011, 1033, 1024, 1024, 1029, 1036, 1026, 1028, 1034, 1031, 1026, 1036, 1030, 1029, 1030, 1039, 1030, 1030, 1028, 1025, 1031, 1041, 1029, 1030, 1031, 1030, 1031, 1030, 1021, 1031, 1030, 1031, 1028, 1040, 1007, 1030, 1035, 1030, 1033, 1028, 1030, 1028, 1031, 1027, 1034, 1035, 1035, 1035, 1037, 1041, 1023, 1033, 1029, 1030, 1038, 1031, 1029, 1030, 1030, 1035, 1029, 1007, 1039, 1030, 1031, 995, 1030, 1034, 1030, 1033, 1038, 1032, 1025, 1025, 1030, 1029, 1031, 1030, 1028, 1028, 1031, 1038, 1034, 1029, 1025, 1030, 1027, 1032, 1027, 1025, 1025, 1021, 1026, 1032, 1038, 1038, 1027, 1031, 1025, 1026, 1043, 995, 1031, 1029, 1024, 1026, 1027, 1030, 1028, 1030, 1030, 1045, 1026, 1016, 1033, 1027, 1031, 1003, 1028, 1021, 1024, 1029, 1041, 1028, 1034, 1030, 1006, 1027, 1031, 1051, 1029, 1020, 1032, 1040, 1029, 1026, 1029, 1025, 1026, 1030, 1030, 1027, 1031, 1026, 1029, 1050, 1049, 1050, 1039, 1039, 1023, 1029, 1019, 1027, 1028, 1039, 1003, 1030, 1031, 1034, 1027, 1031, 1030, 1031, 1030, 1032, 1029, 1020, 1031, 1032, 1029, 1025, 1023, 1036, 1030, 1030, 1032, 1022, 1029, 1032, 1026, 1030, 1032, 1026, 1029, 1024, 1039, 1028, 1029, 1033, 1026, 1031, 1031, 1020, 1030, 1029, 1031, 1031, 1024, 1031, 1032, 1036, 1032, 1031, 1032, 1025, 1073, 1033, 1033, 1007, 1029, 1030, 1031, 1031, 1031, 1031, 1018, 1025, 1031, 1033, 1030, 1029, 1032, 1030, 1031, 1032, 1031, 998, 1032, 1006, 1028, 1030, 1033, 1025, 1031, 1030, 1033, 1026, 1027, 1027, 1033, 1033, 1033, 1030, 1030, 1033, 1030, 1031, 1032, 1028, 1029, 1040, 1030, 1028, 1031, 1035, 1024, 1025, 1031, 1028, 1029, 1038, 1024, 1032, 1030, 1031, 1027, 1031, 1038, 1033, 1026, 1031, 1033, 1022, 1029, 1031, 1024, 1032, 1020, 1030, 1032, 1027, 1028, 1034, 1031, 1029, 1029, 1031, 1030.9, 1027, 1034, 1029, 1029, 1030, 1030, 1032, 1030, 1039, 1034, 1029, 1031, 1030, 1031, 1021, 1033, 1037, 1030, 1031, 1027, 1030, 1027, 1030, 1023, 1023, 1038, 1039, 1029, 1032, 1038, 1031, 1030, 998, 1002, 1029, 1025, 1021, 1021, 1023, 1021, 1032, 1021, 1019, 1031, 1030, 1040, 1029, 1032, 1039, 1039, 1033, 1030, 1031, 1020, 1040, 1027, 1029, 1029, 1028, 1031, 1025, 1039, 1031, 1000, 1001, 1032.1, 1033, 1032, 1031, 1031, 1029, 1026, 1030, 1030, 1029, 1033, 1031, 1031, 1022, 1028, 1029, 1031, 1040, 1030, 1031, 1026, 1036, 1030, 1031, 1031, 1028, 1028, 1031.4, 1032.7, 1030, 1029, 1029, 1029, 1034, 1035.6, 1031, 1028, 1034, 1020, 1026, 1027, 1025, 1030, 1031, 1025.4, 1025, 1035, 1029, 1017, 1020, 1029, 1029.9, 1030, 1030, 1046.6, 1030, 1031, 1033, 1036, 1029, 1030, 1033, 1033, 1033, 1029, 1031, 1029, 1033, 1024, 1024, 1029, 1031.5, 1040, 1030, 1031, 1017, 1019, 1020, 1029, 1030, 1030, 1027, 1028, 1031, 1035, 1031, 1033, 1017, 1027, 1031, 1031.1, 1031, 1027, 1031, 1027, 1022, 1031, 1031, 1028, 1022, 1036, 1032, 1029, 1030, 1027, 1033, 1038, 1015, 1030, 1030, 1030, 1030, 1030, 1028, 1027, 1028, 1032, 1031, 1031, 1017, 1028, 1014, 1026, 1027, 1022, 1029, 1040, 1017, 1033, 1034, 1032, 1032, 1027, 1020, 1026.7, 1022.9, 1039, 1043, 1033, 999, 1020, 1028, 1030, 1030, 1024, 1022, 1025, 1039, 1032, 1028, 1034, 1022, 1027, 1040, 1025, 1049, 1032, 1037, 1030, 1036, 1030, 1032, 1035, 1030, 1028, 1030, 1026, 1039, 1038, 1029, 1030, 1030, 1024, 1030, 1026, 1032, 1033, 1047, 1028, 1030, 1028, 1031, 1030, 1028.6, 1043, 1024.3, 1031, 1039, 1038, 1038, 1032, 1031, 1031, 1033, 1057, 1012, 1013, 1020, 1029, 1029, 1031, 1038.3, 1024.8, 1037, 1033, 1044, 1019, 1024, 1030, 1027, 166.6
Standard polar
1199, 1205, 1197, 1192, 1193, 1194, 1197, 1200, 1203, 1206, 1195, 1205, 1201, 1178, 1205, 1205, 1189, 1180, 1192, 1195, 1204, 1235, 1204, 1195, 1204, 1202, 1204, 1205, 1195, 1192, 1201, 1198, 1205, 1178, 1193, 1205, 1186, 1196, 1193, 1183, 1206, 1207, 1207, 1183, 1184, 1191, 1191, 1175, 1183, 1202, 1235, 1190, 1186, 1206, 1210, 1190, 1200, 1191, 1154, 1185, 1180, 1152, 1178, 1238, 1231, 1205, 1215, 1213, 1195, 1193, 1186, 1201, 1185, 1181, 1199, 1226, 1196, 1181, 1205, 1214, 1208, 1208, 1198, 1205, 1177, 1186, 1169, 1198, 1196, 1196, 1201, 1203, 1210, 1219, 1175, 1211, 1183, 1198, 1190, 1204, 1176, 1196, 1207, 1196, 1195, 1201, 1201, 1200, 1190, 1180, 1200, 1196, 1224, 1224, 1234, 1186, 1198, 1191, 1212, 1183, 1176, 1201, 1185, 1189, 1202, 1211, 1183, 1193, 1183, 1201, 1181, 1209, 1201, 1196, 1155, 1155, 1199, 1183, 1201, 1180, 1187, 1187, 1199, 1193, 1206, 1201, 1213, 1204, 1204, 1201, 1199, 1191, 1183, 1213, 1218, 1184, 1199, 1183, 1187, 1187, 1197, 1185, 1199, 1199, 1193, 1200, 1200, 1200, 1204, 1204, 1197, 1231, 1197, 1195, 1189, 1202, 1153, 1199, 1199, 1183, 1181, 1200, 1188, 1192, 1188, 1192, 1197, 1201, 1181, 1163, 1199, 1199, 1198, 1199, 1190, 1190, 1208, 1200, 1194, 1200, 1200, 1200, 1206, 1195, 1202, 1184, 1200, 1200, 1200, 1194, 1190, 1197, 1195, 1194, 1192, 1203, 1194, 1199, 1204, 1197, 1202, 1203, 1203, 1190, 1201, 1193, 1198, 1187, 1195, 1198, 1229, 1198, 1196, 1193, 1195, 1196, 1184, 1160, 1196, 1198, 1218, 1218, 1202, 1202, 1183, 1178, 1198, 1199, 1207.9, 1216.2, 1221, 1180, 1196, 1180, 1212, 1213, 1189, 1185, 1206, 1206, 1180, 1200, 1200, 1217, 1205, 1200, 1202, 1206, 1186, 1193, 1211, 1189, 1189, 1195, 1196, 1188, 1198, 1200, 1200, 1181, 1196, 1197, 1215, 1192, 1208, 1190, 1188, 1190, 1200, 1180, 1180, 1190, 1192, 1211, 1200, 1202, 1210, 1205.6, 1215.9, 1221.5, 1180, 1181, 1215, 1217, 1208, 1213, 1210, 1242, 1245, 1187, 1204, 1242, 1192, 1203, 1195, 1193, 1188, 1191, 1198, 1197, 1199, 1200, 1203, 1212, 1218, 1193, 1196, 1205, 1203, 1223, 1244, 1203, 1188, 1184, 1201, 1212, 1202, 1235, 1236, 1190, 1223, 1192, 1192, 1204, 1203, 1220, 1190, 1197, 1199, 1203, 1206, 1196, 1188, 1191, 1194, 1177, 1187, 1203, 1171, 1178, 1180, 1199, 1205, 1200, 1202, 1203, 1203, 1178, 1196, 1182, 1187, 1188, 1195, 1202, 1194, 1185, 1240, 1200, 1193, 1194, 1193, 1201, 1218, 1210, 1186, 1206, 1201, 1203, 1203, 1196, 1217, 1178, 1198, 1202, 1208, 1203, 1203, 1203, 1209, 1210, 1219, 1187, 1219, 1181, 1191, 1207, 1195, 1200, 1203, 1239, 1198, 1212, 1201, 1200, 1203, 1203, 1175, 1198, 1200, 1184, 1195, 1178, 1169, 1219, 1205, 1218, 1203, 1203, 1203, 1188, 1200, 1202, 1193, 1206, 1235, 1209, 1203, 1203, 1199, 1199, 1168, 1186, 1211, 1203, 1215, 1202, 1155, 1210, 1198, 1198, 1183, 1206, 1192, 1213, 1203, 1203, 1203, 1201, 1203, 1194, 1194, 1190, 1190, 1195, 1188, 1183, 1203, 1203, 1185, 1187, 1186, 1182, 1207, 1167, 1184, 1164, 1192, 1183, 1184, 1209, 1203, 1203, 1179, 1210, 1231, 1231, 1190, 1191, 1191, 1196, 1196, 1203, 1184, 1203, 1200, 1203, 1192, 1175, 1177, 1190, 1175, 1210, 1203, 1203, 1196, 1201, 1220, 1236, 1222, 1203, 1219, 1181, 1190, 1202, 1202, 1203, 1203, 1191, 1203, 1209, 1195, 1202, 1204, 1190, 1221, 1195, 1204, 1230, 1230, 1203, 1203, 1173, 1196, 1206, 1203, 1203, 1206, 1185, 1190, 1193, 1200, 1186, 1203, 1203, 1192, 1219, 1219, 1205, 1203, 1203, 1198, 1215, 1194, 1206, 1204, 1206, 1198.1, 1190, 1199, 1178, 1204, 1204, 1205, 1203, 1203, 1208, 1207, 1203, 1216, 1190, 1186, 1207.9, 1203, 1210, 1203, 1203, 1203, 1200, 1200, 1203, 1169, 1224, 1192, 1196, 1203, 1206, 1198, 1210, 1204, 1197, 1206, 1192, 1215, 1230, 1203, 1181, 1203, 1215, 1188, 1201, 1207, 1203, 1210, 1188, 1203, 1203, 1199, 1178.5, 1198, 1204, 1204, 1204, 1203, 1203, 1203, 1203, 1203, 1190, 1205, 1203, 1203, 1203, 1203, 1203, 1203, 1197, 1204, 1184, 1188, 1195, 1190, 1166, 1175, 1175, 1176, 1203, 1189, 1187, 1203, 1214, 1197, 1190, 1220, 1203, 1197, 1202, 1219, 1209, 1198, 1203, 1203, 1203, 1203, 1203, 1202, 1221, 1185, 1174.6, 1182.6, 1197, 1211, 1203, 1219, 1197, 1196, 1213, 1194, 1190, 1180, 1179, 1186, 1202, 1187, 1199, 1203, 1210, 1209, 1209, 1203, 1219, 1219, 1219, 1219, 1219, 1219, 1204, 1190, 1190, 1200, 1189, 1205, 1208, 1205, 1204, 1193, 1205, 1198, 1190, 1190, 1184, 1209, 1217, 1201, 1201, 1175, 1176, 1199, 1190, 1202, 1204, 1206, 1190, 1195, 1196, 1206, 1184, 1186, 1198, 1192.4, 1207, 1190, 1184, 1193, 1204, 1180, 1195, 1198, 1218, 1214, 1196, 1198, 1206, 1183, 1188, 1204, 1206, 1180, 1204, 1206, 1206, 1180, 1178.5, 1199, 1209, 1206, 1180, 1202, 1180, 1206, 1180, 1180, 1179, 1181, 1212, 1212, 1212, 1212, 1213, 1213

3.2.20 Other Experimental Properties

Density: 0.8411 at 20 °C; BP: 176-176.4 °C (derived from lemon, bergamont, caraway, orange, and other oils)
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 757
Density: 0.8422 at 20 °C; BP: 176-176.4 °C (derived from peppermint and spearmint oils)
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 757
Oxidizes to a film in air, oxidation behavior similar to that of rubber or drying oils
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 757
With dry hydrogen chloride or hydrogen bromide it forms monohalides, and with aq hydrogen chloride or hydrogen bromide, the dihalide.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021
Liquid; BP: 175.5-176.5 °C; Specific gravity: 0.84007 at 20.5 °C/4 °C; Index of refraction: 1.474 at 21 °C/D; Specific optical rotation: -101.3 °C at 19.5 °C/D /L-limonene/
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021
BP: 177-8 °C at 755 mm Hg, 64.4 °C at 15 mm Hg; density: 0.8422 at 20 °C/4 °C; index of refraction: 1.4746 at 20 °C/D; max absorption (isooctane): 220 nm (log e = 2.4), 250 nm (log e = 1.1); specific optical rotation: -122.1 deg at 20 °C/D (undiluted) /L-limonene/
Lide, D.R. (ed.). CRC Handbook of Chemistry and Physics. 73rd ed. Boca Raton, FL: CRC Press Inc., 1992-1993., p. 3-308
BP: 175.5-176.5 °C; Density: 0.8402 at 20.85 °C/4 °C; Index of refraction: 1.4744 at 25 °C/D. Practically insolulble in water /Inactive limonene/
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021
Hydroxyl radical reaction rate constant = 1.49X10-10 cu cm/molec-sec at 35 °C
Winer AM et al; J Phys Chem: 80: 1635-9 (1976)
Ozone reaction rate constant = 6.5X10-16 cu cm/molec-sec at 25 °C
Atkinson R; Chem Rev 85: 69-201 (1985)

3.3 Chemical Classes

Biological Agents -> Terpenes

3.3.1 Cosmetics

Cosmetics ingredient -> Base; Colorant; Conditioning/Emollient; Emulsifier; Flavor; Fragrance; Moisturizing/Humectant; Opacifying Agent; Other (Specify); Preservative/Stabilizer; Solvent
Solvent
S13 | EUCOSMETICS | Combined Inventory of Ingredients Employed in Cosmetic Products (2000) and Revised Inventory (2006) | DOI:10.5281/zenodo.2624118

3.3.2 Endocrine Disruptors

Potential endocrine disrupting compound
S109 | PARCEDC | List of 7074 potential endocrine disrupting compounds (EDCs) by PARC T4.2 | DOI:10.5281/zenodo.10944198

3.3.3 Food Additives

Use unspecified -> FDA Substance added to food

3.3.4 Fragrances

Fragrance Ingredient (d,l-Limonene (isomer unspecified)) -> IFRA transparency List
Fragrance Ingredient (dl-Limonene (racemic)) -> IFRA transparency List
Fragrance substance (Limonene) -> IFRA amendment 29

4 Spectral Information

4.1 1D NMR Spectra

1D NMR Spectra
NMR: 400 (Johnson and Jankowski, Carbon-13 NMR Spectra, John Wiley & Sons, New York) /L-Limonene/
1D NMR Spectra
NMR: 400 (Johnson and Jankowski, Carbon-13 NMR Spectra, John Wiley & Sons, New York) /DL-Limonene/

4.1.1 1H NMR Spectra

1 of 2
Instrument Name
Varian A-60D
Copyright
Copyright © 2009-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Instrument Name
Varian XL-400
Copyright
Copyright © 2002-2024 Wiley-VCH Verlag GmbH & Co. KGaA. All Rights Reserved.
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4.1.2 13C NMR Spectra

1 of 2
Source of Sample
Heyden-Newport Chemical Corporation, New York, New York
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.2 Mass Spectrometry

4.2.1 GC-MS

1 of 15
View All
Spectra ID
Instrument Type
EI-B
Ionization Mode
positive
Top 5 Peaks

93.0 99.99

68.0 66.98

136.0 62.63

121.0 37.18

67.0 31.55

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Notes
instrument=JEOL JMS-D-3000
2 of 15
View All
MoNA ID
MS Category
Experimental
MS Type
GC-MS
MS Level
MS1
Instrument
JEOL JMS-D-3000
Instrument Type
EI-B
Ionization Mode
positive
Top 5 Peaks

93 99.99

68 66.98

136 62.63

121 37.18

67 31.55

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License
CC BY-NC-SA

4.2.2 MS-MS

Spectra ID
Ionization Mode
Positive
Top 5 Peaks

55.05853 100

91.06173 100

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4.2.3 LC-MS

MS Category
Experimental
MS Type
LC-MS
MS Level
MS2
Precursor Type
[M+H]+
Precursor m/z
137.131
Instrument
SCIEX TripleTOF 6600
Instrument Type
LC-ESI-QTOF
Ionization Mode
positive
Collision Energy
35 eV
Retention Time
0.92045
Top 5 Peaks

91.06173 42

55.05853 42

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4.2.4 Other MS

1 of 2
Other MS
MASS: 704 (Atlas of Mass Spectral Data, John Wiley & Sons, New York) /L-Limonene/
Other MS
MASS: 704 (Atlas of Mass Spectral Data, John Wiley & Sons, New York) /DL-Limonene/
2 of 2
Authors
MASS SPECTROSCOPY SOC. OF JAPAN (MSSJ)
Instrument
JEOL JMS-D-3000
Instrument Type
EI-B
MS Level
MS
Ionization Mode
POSITIVE
Ionization
ENERGY 70 eV
Top 5 Peaks

93 999

68 670

136 626

121 372

67 316

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License
CC BY-NC-SA

4.3 UV Spectra

MAX ABSORPTION (ISOOCTANE): 220 NM (LOG E= 2.41); 250 NM (LOG E= 1.36)
Lide, D.R. (ed.). CRC Handbook of Chemistry and Physics. 73rd ed. Boca Raton, FL: CRC Press Inc., 1992-1993., p. 3-308

4.4 IR Spectra

IR Spectra
IR: 4996 (Coblentz Society Spectral Collection) /L-Limonene/
IR Spectra
IR: 4996 (Coblentz Society Spectral Collection) /DL-Limonene/

4.4.1 FTIR Spectra

1 of 2
Technique
BETWEEN SALTS
Source of Sample
Florida Chemical Company, Inc.
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Instrument Name
Bruker Tensor 27 FT-IR
Technique
Neat
Source of Spectrum
Bio-Rad Laboratories, Inc.
Source of Sample
TCI Chemicals India Pvt. Ltd.
Catalog Number
L0046
Lot Number
LM4PE-EP
Copyright
Copyright © 2016-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.4.2 ATR-IR Spectra

1 of 2
Instrument Name
Bruker Tensor 27 FT-IR
Technique
ATR-Neat (DuraSamplIR II)
Source of Spectrum
Bio-Rad Laboratories, Inc.
Source of Sample
TCI Chemicals India Pvt. Ltd.
Catalog Number
L0046
Lot Number
LM4PE-EP
Copyright
Copyright © 2016-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Source of Sample
Aldrich
Catalog Number
334111
Copyright
Copyright © 2018-2024 Sigma-Aldrich Co. LLC. - Database Compilation Copyright © 2018-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.4.3 Vapor Phase IR Spectra

1 of 2
Instrument Name
DIGILAB FTS-14
Technique
Vapor Phase
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Instrument Name
Bruker IFS 85
Technique
Gas-GC
Copyright
Copyright © 1989, 1990-2024 Wiley-VCH Verlag GmbH & Co. KGaA. All Rights Reserved.
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4.5 Raman Spectra

Instrument Name
Bruker MultiRAM Stand Alone FT-Raman Spectrometer
Technique
FT-Raman
Source of Spectrum
Bio-Rad Laboratories, Inc.
Source of Sample
TCI Chemicals India Pvt. Ltd.
Catalog Number
L0046
Lot Number
LM4PE-EP
Copyright
Copyright © 2016-2024 John Wiley & Sons, Inc. All Rights Reserved.
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6 Chemical Vendors

7 Drug and Medication Information

7.1 FDA National Drug Code Directory

7.2 Drug Labels

Drug and label
Active ingredient and drug

7.3 Clinical Trials

7.3.1 ClinicalTrials.gov

8 Food Additives and Ingredients

8.1 Food Additive Classes

Flavoring Agents

8.2 FDA Substances Added to Food

Substance
Used for (Technical Effect)
Use unspecified
Document Number (21 eCFR)

8.3 Associated Foods

9 Agrochemical Information

9.1 Agrochemical Category

Insecticide

10 Pharmacology and Biochemistry

10.1 Absorption, Distribution and Excretion

The data suggest that monoterpenes are poorly resorbed in the GI tract. The resorbed portion of hydrocarbons accumulates in the lipophilic body compartments and is metabolized and then excreted by the kidneys. /Monoterpenes/
Koppel C et al; Arch Toxicol 49 (1): 73 (1981)
Percutaneous absorption of radioactive limonene from foam bath was measured in animals. Maximum blood level reached after 10 min of exposure and the concentration was proportional to the skin exposed.
Schafer R et al; Arzneimittelforsch 32 (1): 56 (1982)
...SKH-1 mice received topical or oral administration of limonene in the form of orange oil every day for 4 weeks ... Plasma and mammary pads were collected 4 hr after the final dosing. The mouse disposition study showed that topical and oral orange oil administration resulted in similar mammary tissue disposition of limonene with no clinical signs of toxicity ... Our studies showed that limonene is bio available in mammary tissue after topical orange oil application in mice ...
Miller JA et al; J Cancer Ther 3 (5A) (2012)

10.2 Metabolism / Metabolites

After oral administration, major metabolite in urine was perillic acid 8,9-diol in rats and rabbits, perillyl-beta-d-glucopyranosiduronic acid in hamsters, p-menth-1-ene-8,9-diol in dogs, and 8-hydroxy-p-menth-1-en-9-yl-beta-d-glucopyranosiduronic acid in guinea pigs and man.
Kodama R et al; Xenobiotica 6 (6): 377 (1976)
... A metabolite isolated from rabbit urine was identified as p-mentha-1,8-dien-10-ol. ...
Bingham, E.; Cohrssen, B.; Powell, C.H.; Patty's Toxicology Volumes 1-9 5th ed. John Wiley & Sons. New York, N.Y. (2001)., p. V4 185
Limonene given orally to humans yields the following major plasma metabolites: perillic acid, limonene-1,2-diol, limonene-8,9-diol, and dihydroperillic acid, probably derived from perillic acid. Limonene (unchanged) and perillic acid artifacts (methyl ester) were also detected as minor plasma metabolites. Peak plasma levels for all metabolites were achieved 4-6 hours after administration, with the exception of limonene-8,9-diol which reached its peak level one hour after administration. Phase II glucuronic acid conjugates have been identified in the urine of human volunteers for all major and minor metabolites. They include the glucuronic acid conjugates of perillic acid, dihydroperillic acid, limonene-8,9-diol, limonene-10- ol, limonene-6-ol, and limonene-7-ol (perillyl alcohol).
EPA/Office of Pollution Prevention and Toxics; High Production Volume (HPV) Challenge Program's Robust Summaries and Test Plans. Limonene. Available from, as of February 3, 2006: https://www.epa.gov/hpv/pubs/hpvrstp.htm

10.3 Mechanism of Action

The anticarcinogenic effects of monocyclic monoterpenes such as limonene were demonstrated when given during the initiation phase of 7,12-dimethylbenz[a]anthracene induced mammary cancer in Wistar-Furth rats. The possible mechanisms for this chemoprevention activity including limonene's effects on 7,12-dimethylbenz(a)anthracene-DNA adduct formation and hepatic metabolism of 7,12-dimethylbenz[a]anthracene were investigated. Twenty four hours after carcinogen administration, there were approx 50% decreases in 7,12-dimethylbenz(a)anthracene-DNA adducts found in control animals formed in the liver, spleen, kidney and lung of limonene fed animals. While circulating levels of 7,12-dimethylbenz(a)anthracene and/or its metabolites were not different in control and limonene fed rats, there was a 2.3 fold increase in 7,12-dimethylbenz(a)anthracene and/or 7,12-dimethylbenz(a)anthracene derived metabolites in the urine of the limonene fed animals. Limonene and sobrerol, a hydroxylated monocyclic monoterpenoid with increased chemoprevention activity, modulated cytochrome p450 and epoxide hydrolyase activity. The 5% limonene diet increased total cytochrome p450 to the same extent as phenobarbital treatment, while 1% sobrerol (isoeffective in chemoprevention to 5% limonene) did not. However, both 5% limonene and 1% sobrerol diets greatly increased the levels of microsomal epoxide hydrolyase protein and associated hydrating activities towards benzo[a]pyrene 4,5-oxide when compared to control and phenobarbital treatment. These changes also modified the rate and regioselectivity of in vitro microsomal 7,12-dimethylbenz(a)anthracene metabolism when compared to phenobarbital treatment or control. Identification of the specific isoforms of cytochrome p450 induced by these terpenoids was performed with antibodies to cytochrome p450 isozymes in Western blot analysis and inhibition studies of microsomal 7,12-dimethylbenz(a)anthracene metabolism. Five percent limonene was more effective than 1% sobrerol at increasing the levels of members of the cytochrome p450 2B and 2C families but was equally effective at increasing epoxide hydrolyase. Furthermore, both terpenoid diets caused increased formation of the proximate carcinogen, 7,12-dimethylbenz(a)anthracene 3,4-dihydrodiol.
Maltzman TH et al; Carcinogenesis 12 (11): 2081-7 (1991)

10.4 Human Metabolite Information

10.4.1 Cellular Locations

  • Extracellular
  • Membrane

10.5 Biochemical Reactions

10.6 Transformations

11 Use and Manufacturing

11.1 Uses

EPA CPDat Chemical and Product Categories
The Chemical and Products Database, a resource for exposure-relevant data on chemicals in consumer products, Scientific Data, volume 5, Article number: 180125 (2018), DOI:10.1038/sdata.2018.125
Sources/Uses
Used in flavorings, fragrances, cosmetics and as a solvent and wetting agent; Also used to make resins, insecticides, insect repellants, and animal repellants; [HSDB] Used as a dissolving agent for gallstones and gutta-percha; [ChemIDplus] Used in floor waxes and furniture polishes; [CAMEO] Occurs naturally in essential oils of many plants and is a minor constituent of turpentine; [CHEMINFO]
Industrial Processes with risk of exposure
Painting (Solvents) [Category: Paint]
For limonene (USEPA/OPP Pesticide Code: 079701) there are 0 labels match. /SRP: Not registered for current use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./
National Pesticide Information Retrieval System's Database on Limonene (138-86-3). Available from, as of April 27, 2015: https://npirspublic.ceris.purdue.edu/ppis/
Monomer in terpene resins; solvent for oleoresinous products; general wetting and dispersing agent; chemical intermediate for various organic compounds; flavor ingredient (orange-like).
SRI
One important use for (R)-(+)-limonene is its use as a chiral starting material for the synthesis of (R)-(-)-carvone.
Sell CS; Terpenoids. Kirk-Othmer Encyclopedia of Chemical Technology (1999-2015). John Wiley & Sons, Inc. Online Posting Date: September 15, 2006
An application for printed circuit board cleaners has also been developed using dipentene and limonene with emulsifying surfactants to facilitate removal by rinsing in water.
Sell CS; Terpenoids. Kirk-Othmer Encyclopedia of Chemical Technology (1999-2015). John Wiley & Sons, Inc. Online Posting Date: September 15, 2006
For more Uses (Complete) data for LIMONENE (13 total), please visit the HSDB record page.

11.1.1 Use Classification

Food additives -> Flavoring Agents
Fragrance Ingredients
Hazard Classes and Categories -> Flammable - 2nd degree
Cosmetics -> Solvent
S13 | EUCOSMETICS | Combined Inventory of Ingredients Employed in Cosmetic Products (2000) and Revised Inventory (2006) | DOI:10.5281/zenodo.2624118

11.1.2 Industry Uses

  • Adhesion/cohesion promoter
  • Fuels and fuel additives
  • Intermediates
  • Monomers
  • Odor agents
  • Fragrance

11.1.3 Consumer Uses

  • Fuels and fuel additives
  • Fragrance
  • Odor agents

11.1.4 Household Products

California Safe Cosmetics Program (CSCP)

Cosmetics product ingredient: Limonene (1-methyl-4-prop-1-en-2-yl-cyclohexene; dl-limonene (racemic); Dipentene; (R)-p-mentha-1,8-diene; (d-limonene); (S)-p-mentha-1,8-diene; (l-limonene))

Limonene is a fragrance allergen. Fragrance allergens are hazardous only to individuals who suffer from fragrance allergies. The Cosmetic Fragrance and Flavor Ingredient Right to Know Act of 2020 requires fragrance allergens included in Annex III of the EU Cosmetics Regulation No. 1223/2009 be reported to the California Department of Public Health. Fragrance allergens are only required to be reported if present in a rinse-off cosmetic product at a concentration at or above 0.01 percent (100 parts per million) or in a leave-on cosmetic product at a concentration at or above 0.001 percent (10 parts per million).

Product count: 28499

Household & Commercial/Institutional Products

Information on 149 consumer products that contain Dipentene in the following categories is provided:

• Auto Products

• Commercial / Institutional

• Inside the Home

• Personal Care

Household & Commercial/Institutional Products

Information on 6 consumer products that contain 1-Methyl-4-Methylvinyl-Cyclohexene in the following categories is provided:

• Auto Products

11.2 Methods of Manufacturing

Extraction from Southeastern pine stumps, and citrus fruits (especially from the peels of oranges and lemons); from pyrolysis of alpha-pinene
SRI
As a by-product in the manufacture of terpineol and in various synthetic products made from alpha-pinene or turpentine oil.
Opdyke, D.L.J. (ed.). Monographs on Fragrance Raw Materials. New York: Pergamon Press, 1979., p. 333
Derivation: (1) Lemon, bergamot, caraway, orange, and other oils, (2) peppermint and spearmint oils.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 757
The richest sources are the oils contained in the peel of citrus fruits, which contain levels up to 90%. The major source of limonene is ... from citrus peel, largely as a by-product of the fruit juice industry. Citrus fruit produce the (R)-enantiomer and so the bulk of commercially available limonene is dextrorotatory. The levorotatory enantiomer is available, but in much more restricted supply and at a higher price.
Sell CS; Terpenoids. Kirk-Othmer Encyclopedia of Chemical Technology (1999-2015). John Wiley & Sons, Inc. Online Posting Date: September 15, 2006

11.3 IFRA Fragrance Standards

IFRA Substance
Limonene
Synonyms
p-Mentha-1,8-diene; 1-methyl-4-prop-1-en-2-ylcyclohexene; 1-Methyl-4-(1-methylethenyl)cyclohexene; 1-Methyl-4-isopropenyl-1-cyclohexene; 4-Isopropenyl-1-methylcyclohexene; Cyclohexene, 1-methyl-4-(1-methylethenyl)-; Dipentene
Amendment
29
IFRA Standard type
Specification: This material should be used only if it meets the criteria stated in the Standard
Intrinsic property driving the risk management measure
DERMAL SENSITIZATION
Flavor use consideration
Due to the possible ingestion of small amounts of fragrance ingredients from their use in products in Categories 1 and 6, materials must not only comply with IFRA Standards but must also be recognized as safe as a flavoring ingredient as defined by the IOFI Code of Practice (www.iofi.org). For more details see chapter 1 of the Guidance for the use of IFRA Standards.
Specified ingredients: notes

Oxidation products of Limonene, especially hydroperoxides, have been demonstrated to be potent sensitizers.

d-, l- and dl-Limonene and natural products containing substantial amounts of it, should only be used when the level of (hydro)peroxides is kept to the lowest practical level, for instance by adding antioxidants at the time of production. The addition of 0.1% BHT or α-Tocopherol for example has shown great efficiency. Such products should have a peroxide value of less than 20 millimoles per liter, determined according to the IFRA analytical method for the determination of the peroxide value, which can be downloaded from the IFRA website (www.ifrafragrance.org).

11.4 Impurities

Impurities are mainly other monoterpenes, such as myrcene (7-methyl-3-methylene-1,6-octadiene), alpha-pinene (2,6,6-trimethyl-bicyclo[3.1.1]hept-2-ene), alpha-pinene (6,6-dimethyl-2-methylene-bicyclo[3.1.1]heptane), sabinene (2-methyl-5-(1-methylethyl)-bicyclo[3.1.0]hexan-2-ol), and Gamma3-carene ((1S-cis)-3,7,7-trimethyl-bicyclo[4.1.0]hept-2-ene).
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene (1998). Available from, as of July 28, 2015: https://www.inchem.org/pages/cicads.html

11.5 Formulations / Preparations

Dipenten
Bingham, E.; Cohrssen, B.; Powell, C.H.; Patty's Toxicology Volumes 1-9 5th ed. John Wiley & Sons. New York, N.Y. (2001)., p. V4 184
Dipentene, mixture of limonene, 56-64%, and terpinolene, 20-25%
Bingham, E.; Cohrssen, B.; Powell, C.H.; Patty's Toxicology Volumes 1-9 5th ed. John Wiley & Sons. New York, N.Y. (2001)., p. 4:184

11.6 Consumption Patterns

Use in fragrances in the USA amounts to <1000 lb/yr.
Opdyke, D.L.J. (ed.). Monographs on Fragrance Raw Materials. New York: Pergamon Press, 1979., p. 333

11.7 U.S. Production

Aggregated Product Volume

2019: 10,000,000 - <50,000,000 lb

2018: 1,000,000 - <10,000,000 lb

2017: 10,000,000 - <50,000,000 lb

2016: 10,000,000 - <50,000,000 lb

(1986) >10 million-50 million pounds
US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Cyclohexene, 1-methyl-4-(1-methylethenyl)-(138-86-3). Available from, as of January 19, 2006: https://www.epa.gov/oppt/iur/tools/data/2002-vol.html
(1990) 10 thousand-500 thousand pounds
US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Cyclohexene, 1-methyl-4-(1-methylethenyl)-(138-86-3). Available from, as of January 19, 2006: https://www.epa.gov/oppt/iur/tools/data/2002-vol.html
(1994) 10 thousand-500 thousand pounds
US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Cyclohexene, 1-methyl-4-(1-methylethenyl)-(138-86-3). Available from, as of January 19, 2006: https://www.epa.gov/oppt/iur/tools/data/2002-vol.html
(1998) >1 million-10 million pounds
US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Cyclohexene, 1-methyl-4-(1-methylethenyl)-(138-86-3). Available from, as of January 19, 2006: https://www.epa.gov/oppt/iur/tools/data/2002-vol.html
For more U.S. Production (Complete) data for LIMONENE (7 total), please visit the HSDB record page.

11.8 General Manufacturing Information

Industry Processing Sectors
  • All Other Basic Organic Chemical Manufacturing
  • Transportation Equipment Manufacturing
  • All Other Chemical Product and Preparation Manufacturing
  • Soap, Cleaning Compound, and Toilet Preparation Manufacturing
  • Plastics Material and Resin Manufacturing
EPA TSCA Commercial Activity Status
Cyclohexene, 1-methyl-4-(1-methylethenyl)-: ACTIVE
Concentration in final product (%): as usual to maximum range is 0.05-0.75 in soap; 0.05-0.075 in detergent; 0.5-2.0 in perfume and 0.25 maximum in creams and lotions.
Opdyke, D.L.J. (ed.). Monographs on Fragrance Raw Materials. New York: Pergamon Press, 1979., p. 333
A widely distributed, optically active terpene, closely related to isoprene. It occurs naturally in both d- and l-forms. Racemic mixture of the two isomers is known as dipentene.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 757
Limonene is the most important and widespread terpene; it is known in the d- and l- optically active forms and in the optically inactive dl-form (known as dipentene).
Burdock, G.A. (ed.). Fenaroli's Handbook of Flavor Ingredients. 6th ed.Boca Raton, FL 2010, p. 1090

11.9 Sampling Procedures

Air analysis Volatile org cmpd detn in indoor air from tobacco smoke by using multisorbent thermal desorption/GC/mass selective detection.
Heavner DL et al; Environ Sci Technol 26 (9): 1737-46 (1992)

12 Identification

12.1 Analytic Laboratory Methods

Method: NIOSH 1552, Issue 1; Procedure: gas chromatography with flame ionization detection; Analyte: limonene (d- & l-); Matrix: air; Detection Limit: 0.4 ug/sample.
CDC; NIOSH Manual of Analytical Methods, 4th ed. Terpenes. Available from, as of April 29, 2015: https://www.cdc.gov/niosh/docs/2003-154/
Method: OSHA PV2036; Procedure: gas chromatography with flame ionization detection; Analyte: limonene; Matrix: air; Detection Limit: 0.08 ppm (0.44 mg/cu m).
U.S. Department of Labor/Occupational Safety and Health Administration's Index of Sampling and Analytical Methods. Limonene (138-86-3). Available from, as of April 29, 2015: https://www.osha.gov/dts/sltc/methods/toc.html
The citrus-derived bioactive monoterpene limonene is an important industrial commodity and fragrance constituent. An RP isocratic elution C18 ultra-HPLC (UHPLC) method using a superficially porous stationary phase and photodiode array (PDA) detector has been developed for determining the limonene content of sweet orange (Citrus sinensis) oil. The method is fast with a cycle time of 1.2 min, linear, precise, accurate, specific, and stability indicating, and it satisfies U.S. Pharmacopeia suitability parameters. The method may be useful in its present form for limonene processing, or modified for research on more polar compounds of the terpenome. A forced-degradation experiment showed that limonene is degraded by heat in hydro-ethanolic solution. PDA detection facilitates classification of minor components of the essential oil, including beta-myrcene.
Bernart MW; J AOAC Int 98 (1): 94-7 (2015)
Some citrus essential oils were analyzed by HPLC with both microbore and std columns in reversed and normal phase. Volatile and non-volatile fraction were investigated. In the non-volatile fraction some coumarins were identified. Fractions are detected spectrophotometrically at 220 and 320 nm before and after evap of samples.
Benincasa M et al; Chromatographia 30 (5-6): 271-6 (1990)
Volatile org determination of indoor air tobacco smoke by multisorbent thermal desorption/GC/mass selective detection in relation to tracers ethenylpyridine, as indicator of environmental tobacco smoke.
Heavner DL et al; Environ Sci Technol 26 (9): 1737-46 (1992)

12.2 NIOSH Analytical Methods

13 Safety and Hazards

13.1 Hazards Identification

13.1.1 GHS Classification

1 of 7
View All
Note
Pictograms displayed are for > 99.9% (3469 of 3470) of reports that indicate hazard statements. This chemical does not meet GHS hazard criteria for < 0.1% (1 of 3470) of reports.
Pictogram(s)
Flammable
Irritant
Health Hazard
Environmental Hazard
Signal
Danger
GHS Hazard Statements

H226 (> 99.9%): Flammable liquid and vapor [Warning Flammable liquids]

H304 (49.1%): May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H315 (> 99.9%): Causes skin irritation [Warning Skin corrosion/irritation]

H317 (> 99.9%): May cause an allergic skin reaction [Warning Sensitization, Skin]

H319 (16%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H400 (98.6%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410 (> 99.9%): Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

Precautionary Statement Codes

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P272, P273, P280, P301+P316, P302+P352, P303+P361+P353, P305+P351+P338, P321, P331, P332+P317, P333+P317, P337+P317, P362+P364, P370+P378, P391, P403+P235, P405, and P501

(The corresponding statement to each P-code can be found at the GHS Classification page.)

ECHA C&L Notifications Summary

Aggregated GHS information provided per 3470 reports by companies from 44 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 3470 reports by companies. For more detailed information, please visit ECHA C&L website.

There are 43 notifications provided by 3469 of 3470 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown.

13.1.2 Hazard Classes and Categories

Flam. Liq. 3 (> 99.9%)

Asp. Tox. 1 (49.1%)

Skin Irrit. 2 (> 99.9%)

Skin Sens. 1B (> 99.9%)

Eye Irrit. 2 (16%)

Aquatic Acute 1 (98.6%)

Aquatic Chronic 1 (> 99.9%)

Flam. Liq. 3 (100%)

Asp. Tox. 1 (46.2%)

Skin Irrit. 2 (100%)

Skin Sens. 1 (100%)

Aquatic Acute 1 (100%)

Aquatic Chronic 1 (100%)

13.1.3 NFPA Hazard Classification

1 of 2
View All
NFPA 704 Diamond
2-2-0
NFPA Health Rating
2 - Materials that, under emergency conditions, can cause temporary incapacitation or residual injury.
NFPA Fire Rating
2 - Materials that must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur. Materials would not under normal conditions form hazardous atmospheres with air, but under high ambient temperatures or under moderate heating could release vapor in sufficient quantities to produce hazardous atmospheres with air.
NFPA Instability Rating
0 - Materials that in themselves are normally stable, even under fire conditions.

13.1.4 Health Hazards

Liquid irritates eyes; prolonged contact with skin causes irritation. Ingestion causes irritation of gastrointestinal tract. (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
ERG 2024, Guide 128 (Dipentene)

CAUTION: Petroleum crude oil (UN1267) may contain TOXIC hydrogen sulphide gas.

· Inhalation or contact with material may irritate or burn skin and eyes.

· Fire may produce irritating, corrosive and/or toxic gases.

· Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas.

· Runoff from fire control or dilution water may cause environmental contamination.

13.1.5 Fire Hazards

Behavior in Fire: Containers may explode. (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
ERG 2024, Guide 128 (Dipentene)

· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.

· Vapors may form explosive mixtures with air.

· Vapors may travel to source of ignition and flash back.

· Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.).

· Vapor explosion hazard indoors, outdoors or in sewers.

· Those substances designated with a (P) may polymerize explosively when heated or involved in a fire.

· Runoff to sewer may create fire or explosion hazard.

· Containers may explode when heated.

· Many liquids will float on water.

· Substance may be transported hot.

· For hybrid vehicles, GUIDE 147 (lithium ion or sodium ion batteries) or GUIDE 138 (sodium batteries) should also be consulted.

· If molten aluminum is involved, refer to GUIDE 169.

13.1.6 Hazards Summary

Skin and eye irritant; A skin sensitizer; [HSDB] Danger of skin sensitization; [MAK] An irritant; May cause skin sensitization; [MSDSonline] The racemic mixture of d-limonene and l-limonene is called dipentene (138-86-3).[Kanerva, p. 1789] See l-Limonene and d-Limonene.
Kanerva - Rustemeyer L, Elsner P, John SM, Maibach HI (eds). Kanerva's Occupational Dermatology, 2nd Ed. Berlin: Springer-Verlag, 2012., p. 1789

13.1.7 Fire Potential

Flammable when exposed to heat or flame.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2295

13.1.8 Skin, Eye, and Respiratory Irritations

Skin irritant.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1021
Contact can irritate the eyes and skin.
Pohanish, R.P. (ed). Sittig's Handbook of Toxic and Hazardous Chemical Carcinogens 6th Edition Volume 1: A-K,Volume 2: L-Z. William Andrew, Waltham, MA 2012, p. 1106
Liquid irritates eyes; ingestion causes irritation of GI tract.
U.S. Coast Guard, Department of Transportation. CHRIS - Hazardous Chemical Data. Volume II. Washington, D.C.: U.S. Government Printing Office, 1984-5.
The monoterpenes (such as ... and limonene) are major components of the resin from many common softwoods and are associated with mouth and throat irritation, shortness of breath, and impaired lung function.
International Labour Office. Encyclopaedia of Occupational Health and Safety. 4th edition, Volumes 1-4 1998. Geneva, Switzerland: International Labour Office, 1998., p. 71.9

13.2 Safety and Hazard Properties

13.2.1 Flammable Limits

Lower flammable limit: 0.7% by volume; Upper flammable limit: 6.1% by volume (at 302 °F (150 °C))
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-53

13.2.2 Lower Explosive Limit (LEL)

0.7 % (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
0.7%

13.2.3 Upper Explosive Limit (UEL)

6.1 % (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
6.1%

13.3 First Aid Measures

13.3.1 First Aid

INHALATION: remove victim from contaminated area; administer artificial respiration if necessary; call physician.

EYES: flush with water for 15 min.; call physician.

SKIN: wash with soap and water.

INGESTION: induce vomiting; call physician. (USCG, 1999)

U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
ERG 2024, Guide 128 (Dipentene)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingestedor inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuouscompressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· Wash skin with soap and water.

· In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

13.4 Fire Fighting

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient. CAUTION: For mixtures containing alcohol or polar solvent, alcohol-resistant foam may be more effective.

SMALL FIRE: Dry chemical, CO2, water spray or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

LARGE FIRE: Water spray, fog or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam. Avoid aiming straight or solid streams directly onto the product. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. For petroleum crude oil, do not spray water directly into a breached tank car. This can lead to a dangerous boil over. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)

13.5 Accidental Release Measures

Public Safety: ERG 2024, Guide 128 (Dipentene)

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Ventilate closed spaces before entering, but only if properly trained and equipped.

Spill or Leak: ERG 2024, Guide 128 (Dipentene)

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· All equipment used when handling the product must be grounded.

· Do not touch or walk through spilled material.

· Stop leak if you can do it without risk.

· Prevent entry into waterways, sewers, basements or confined areas.

· A vapor-suppressing foam may be used to reduce vapors.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· Use clean, non-sparking tools to collect absorbed material.

Large Spill

· Dike far ahead of liquid spill for later disposal.

· Water spray may reduce vapor, but may not prevent ignition in closed spaces.

13.5.1 Isolation and Evacuation

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet).

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

Evacuation: ERG 2024, Guide 128 (Dipentene)

Immediate precautionary measure

· Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

Large Spill

· Consider initial downwind evacuation for at least 300 meters (1000 feet).

Fire

· If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.

13.5.2 Cleanup Methods

If a spill occurs, clean it up promptly. Don't wash it away. Instead, sprinkle the spill with sawdust, vermiculite, or kitty litter. Sweep it into a plastic garbage bag, and dispose of it as directed on the pesticide product label.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.20 (Septemper 1995) EPA 730-K-95-001
After Applying a Pesticide, Indoors or Outdoors. To remove pesticide residues, use a bucket to rinse tools or equipment three times, including any containers or utensils that you used when mixing the pesticide. Then pour the rinsewater into the pesticide sprayer and reuse the solution by applying it according to the pesticide product label directions. After applying any pesticide wash your hands and any other parts of your body that may have come in contact with the pesticide..To prevent tracking pesticides inside, remove or rinse your boots or shoes before entering your home. Wash any clothes that have been exposed to a lot of pesticide separately from your regular wash.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.22 (Septemper 1995) EPA 730-K-95-001

13.5.3 Disposal Methods

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.
Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber.
Pohanish, R.P. (ed). Sittig's Handbook of Toxic and Hazardous Chemical Carcinogens 6th Edition Volume 1: A-K,Volume 2: L-Z. William Andrew, Waltham, MA 2012, p. 1107
Safe Disposal of Pesticides. The best way to dispose of small amounts of excess pesticides is to use them - apply them - according to the directions on the label. If you cannot use them, ask your neighbors whether they have a similar pest control problem and can use them. If all of the remaining pesticide cannot be properly used, check with your local solid waste management authority, environmental agency, or health department to find out whether your community has a household hazardous waste collection program or a similar program for getting rid of unwanted, leftover pesticides. These authorities can also inform you of any local requirements for pesticide waste disposal.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.24 (Septemper 1995) EPA 730-K-95-001
Safe Disposal of Pesticides. An empty pesticide container can be as hazardous as a full one because of residues left inside. Never reuse such a container. When empty, a pesticide container should be rinsed carefully three times and the rinsewater thoroughly drained back onto the sprayer or the container previously used to mix the pesticide. Use the rinsewater as a pesticide, following label directions. Replace the cap or closure securely. Dispose of the container according to label instructions. Do not puncture or burn a pressurized container like an aerosol - it could explode. Do cut or puncture other empty pesticide containers made of metal or plastic to prevent someone from reusing them. Wrap the empty container and put it in the trash after you have rinsed it.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.25 (Septemper 1995) EPA 730-K-95-001

13.5.4 Preventive Measures

SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.
Wear the items of protective clothing the label requires: for example, non-absorbent gloves (not leather or fabric), rubber footwear (not canvas or leather), a hat, goggles, or a dust-mist filter. If no specific clothing is listed, gloves, long-sleeved shirts and long pants, and closed shoes are recommended. You can buy protective clothing and equipment at hardware stores or building supply stores.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.19 (Septemper 1995) EPA 730-K-95-001
Indoor Applications. If the label directions permit, leave all windows open and fans operating after the application is completed. If the pesticide product is only effective in an unventilated (sealed) room or house, do not stay there. Put all pets outdoors, and take yourself any your family away from treated areas for at least the length of time prescribed on the label. Apply most surface sprays only to limited areas such as cracks; don't treat entire floors, walls, or ceilings. Don't let pesticides get on any surfaces that are used for food preparation. Wash any surfaces that may have pesticide residue before placing food on them.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.20 (Septemper 1995) EPA 730-K-95-001
Indoor Applications. When using total release foggers to control pests, use no more than the amount needed and to keep foggers away from ignition sources (ovens, stoves, air conditioners, space heaters, and water heaters, for example). Foggers should not be used in small, enclosed places such as closets and cabinets or under tables and counters.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.21 (Septemper 1995) EPA 730-K-95-001
Outdoor Applications. Never apply pesticides outdoors on a windy day (winds higher than 10 mph). Position yourself so that a light breeze does not blow pesticide spray or dust into your face.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.21 (Septemper 1995) EPA 730-K-95-001

13.6 Handling and Storage

13.6.1 Nonfire Spill Response

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)

13.6.2 Storage Conditions

Store in a flammable liquid storage area or approved cabinet away from ignition sources and corrosive and reacting materials. ... Store in tightly closed containers in a cool, well ventilated area away from heat and incompatible materials.
Pohanish, R.P. (ed). Sittig's Handbook of Toxic and Hazardous Chemical Carcinogens 6th Edition Volume 1: A-K,Volume 2: L-Z. William Andrew, Waltham, MA 2012, p. 1107
Safe Storage of Pesticides. Always store pesticides in their original containers, complete with labels that list ingredients, directions for use, and first aid steps in case of accidental poisoning. Never store pesticides in cabinets with or near food, animal feed, or medical supplies. Do not store pesticides in places where flooding is possible or in places where they might spill or leak into wells, drains, ground water, or surface water.
USEPA/Prevention, Pesticides, and Toxic Substances; Citizen's Guide to Pest Control and Pesticide Safety p.23 (Septemper 1995) EPA 730-K-95-001

13.7 Exposure Control and Personal Protection

Protective Clothing: ERG 2024, Guide 128 (Dipentene)

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

13.7.1 Emergency Response Planning Guidelines

Emergency Response: ERG 2024, Guide 128 (Dipentene)

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

CAUTION: For mixtures containing alcohol or polar solvent, alcohol-resistant foam may be more effective.

Small Fire

· Dry chemical, CO2, water spray or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

Large Fire

· Water spray, fog or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

· Avoid aiming straight or solid streams directly onto the product.

· If it can be done safely, move undamaged containers away from the area around the fire.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Cool containers with flooding quantities of water until well after fire is out.

· For petroleum crude oil, do not spray water directly into a breached tank car. This can lead to a dangerous boil over.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

· For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn.

13.7.2 Other Standards Regulations and Guidelines

Workplace Environmental Exposure Level (WEEL): 8-hr Time-weighted Average (TWA) 30 ppm. Last Revised: 1993.
Toxicology Excellence for Risk Assessment; Occupational Alliance for Risk Science - Workplace Environmental Exposure Levels. Limonene, d- (138-86-3). Available from, as of April 23, 2015: https://www.tera.org/OARS/WEEL.html

13.7.3 Personal Protective Equipment (PPE)

Solvent-resistant gloves; safety glasses or face shield; self- contained breathing apparatus for high vapor concentrations. (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
Wear protective gloves and clothing to prevent any reasonable probability of skin contact.
Pohanish, R.P. (ed). Sittig's Handbook of Toxic and Hazardous Chemical Carcinogens 6th Edition Volume 1: A-K,Volume 2: L-Z. William Andrew, Waltham, MA 2012, p. 1107

13.8 Stability and Reactivity

13.8.1 Air and Water Reactions

Flammable. Insoluble in water.

13.8.2 Reactive Group

Hydrocarbons, Aliphatic Unsaturated

13.8.3 Reactivity Profile

DIPENTENE may react vigorously with strong oxidizing agents. May react exothermically with reducing agents to release hydrogen gas.

13.8.4 Hazardous Reactivities and Incompatibilities

Forms explosive mixture with air. Contact with oxidizers may cause fire and explosion hazard.
Pohanish, R.P. (ed). Sittig's Handbook of Toxic and Hazardous Chemical Carcinogens 6th Edition Volume 1: A-K,Volume 2: L-Z. William Andrew, Waltham, MA 2012, p. 1106
Accidental contamination of a tetrafluoroethylene gas supply system with iodine pentafluoride caused a violent explosion in the cylinders. Exothermic reaction of ... limonene, /the polymerization/ inhibitor /of tetrafluoroethylene/, with the contaminant present in the gas cylinders may have depleted the inhibitor and initiated explosive polymerization. /D-Limonene/
Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990, p. 216
Addition of molten sulfur to limonene in a 9 kl /critical/ reactor led to a violent runaway exothermic reaction. Small scale pilot runs had not shown the possibility of this. Heating terpenes strongly with sulfur usually leads to formation of benzene derivatives with evolution of hydrogen sulfide.
Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990, p. 1450
... Can react vigorously with oxidizing material.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2295

13.8.5 Peroxide Forming Chemical

Chemical
Limonene
Class (* = UMN Designation)
D*: Other compounds that may form peroxides
Reference(s)

13.9 Transport Information

13.9.1 DOT Emergency Guidelines

/GUIDE 128 FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. Substance may be transported hot. For UN3166, if Lithium ion batteries are involved, also consult GUIDE 147. If molten aluminum is involved, refer to GUIDE 169.
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 128 FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible)/ Health: Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 128 FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible)/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering.
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 128 FLAMMABLE LIQUIDS (Non-Polar/Water-Immiscible)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection.
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
For more DOT Emergency Guidelines (Complete) data for LIMONENE (8 total), please visit the HSDB record page.

13.9.2 Shipping Name / Number DOT/UN/NA/IMO

UN 2052; Dipentene
IMO 3; Dipentene

13.9.3 Shipment Methods and Regulations

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./
49 CFR 171.2 (USDOT); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of April 28, 2015: https://www.ecfr.gov
The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.
International Air Transport Association. Dangerous Goods Regulations. 55th Edition. Montreal, Quebec Canada. 2014., p. 233
The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.
International Maritime Organization. IMDG Code. International Maritime Dangerous Goods Code Volume 2 2012, p. 103

13.9.4 DOT Label

Flammable Liquid

13.10 Regulatory Information

The Australian Inventory of Industrial Chemicals

Chemical: Cyclohexene, 1-methyl-4-(1-methylethenyl)-

Specific Information Requirement: Obligations to provide information apply. You must tell us within 28 days if the circumstances of your importation or manufacture (introduction) are different to those in our assessment.

The Australian Inventory of Industrial Chemicals

Chemical: Cyclohexene, 1-methyl-4-(1-methylethenyl)-, (R)-

Specific Information Requirement: Obligations to provide information apply. You must tell us within 28 days if the circumstances of your importation or manufacture (introduction) are different to those in our assessment.

California Safe Cosmetics Program (CSCP) Reportable Ingredient

Hazard Traits - Fragrance Allergen

Authoritative List - Annex III of the EU Cosmetics Regulation No. 1223/2009 - Fragrance Allergens

Report - if present in a rinse-off cosmetic product at a concentration at or above 0.01 percent (100 parts per million) or in a leave-on cosmetic product at a concentration at or above 0.001 percent (10 parts per million)

REACH Registered Substance
New Zealand EPA Inventory of Chemical Status
Cyclohexene, 1-methyl-4-(1-methylethenyl)-: HSNO Approval: HSR001142 Approved with controls

13.10.1 FIFRA Requirements

Based on the reviews of the generic data for the active ingredients Limonene, the Agency has sufficient information on the health effects of Limonene and on its potential for causing adverse effects in fish and wildlife and the environment. Therefore, the Agency concludes that products containing Limonene for all uses are eligible for reregistration. The Agency has determined that limonene products, labeled and used as specified in this Reregistration Eligibility Decision, will not pose unreasonable risks or adverse effects to humans or the environment.
USEPA/Office of Prevention, Pesticides and Toxic Substances; Reregistration Eligibility Decision Document for Limonene p.20, EPA 738-R-94-034 (September 1994). Available from, as of June 3, 2015: https://www.epa.gov/pesticides/reregistration/status.htm
As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their continued use. Under this pesticide reregistration program, EPA examines newer health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether the use of the pesticide does not pose unreasonable risk in accordance to newer safety standards, such as those described in the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA '88 were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern than those on List C, and with List C containing pesticides of greater concern than those on List D. Limonene is found on List C. Case No: 3083; Pesticide type: insecticide, rodenticide; Case Status: RED Approved 09/94; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): limonene; Data Call-in (DCI) Date(s): 09/30/92, 09/08/94; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) for the case/AI.
United States Environmental Protection Agency/ Prevention, Pesticides and Toxic Substances; Status of Pesticides in Registration, Reregistration, and Special Review. (1998) EPA 738-R-98-002, p. 261

13.10.2 FDA Requirements

Synthetic flavoring substances and adjuvants /for human consumption/ that are generally recognized as safe for their intended use, within the meaning of section 409 of the Act. Limonene (d-, l-, and dl-) is included on this list.
21 CFR 182.60 (USFDA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of April 21, 2015: https://www.ecfr.gov
Synthetic flavoring substances and adjuvants /for animal drugs, feeds, and related products/ that are generally recognized as safe for their intended use, within the meaning of section 409 of the Act. Limonene (d-, l-, and dl-) is included on this list.
21 CFR 582.60 (USFDA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of April 21, 2015: https://www.ecfr.gov

13.11 Other Safety Information

Chemical Assessment
PEC / SN / Other assessments - Limonene: Health and Environment

13.11.1 Special Reports

USEPA/Office of Prevention, Pesticides and Toxic Substances; Reregistration Eligibility Decision Document (RED) - Limonene, EPA 738-R-94-034 (September 1994). The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.[Available from, as of June 3, 2015: http://www.epa.gov/pesticides/reregistration/status.htm]

14 Toxicity

14.1 Toxicological Information

14.1.1 Toxicity Summary

IDENTIFICATION AND USE: Limonene is a colorless liquid. It is not registered for current pesticide use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses. Limonene is used as a solvent in degreasing metals prior to industrial painting, for cleaning in the electronic and printing industries, and in paint as a solvent. Limonene is also used as a flavor and fragrance additive in food, household cleaning products and perfumes. It is also used as gallstone solubilizer. HUMAN EXPOSURE AND TOXICITY: Limonene is a skin irritant in humans. The oxidized forms of limonene are known to cause allergic contact dermatitis. Limonene liquid has been reported to irritate eyes, ingestion causes irritation of GI tract. Albuminuria and hematuria are probable if ingested in sufficient quantity. It is also associated with mouth and throat irritation, shortness of breath, and impaired lung function. ANIMAL STUDIES: Limonene is a skin irritant in experimental animals. The critical organ in animals (except for male rats) following oral or ip administration is the liver. Exposure to limonene affects the amount and activity of different liver enzymes, liver weight, cholesterol levels and bile flow. These changes have been noted in mice, rats and dogs. Limonene and its epoxides were not mutagenic when tested at concentrations of 0.3-3333 ug/plate in in vitro assays using different strains of Salmonella typhimurium, in the presence or absence of metabolic activation. When incubated with Syrian hamster embryo cells up to 100 ug/mL or 3 mM, limonene did not induce statistically significant cell transformation. There is no evidence that limonene was teratogenic or produced embryotoxic effects in the absence of maternal toxicity. ECOTOXICITY STUDIES: Terrestrial organisms are most likely exposed to limonene via the air. The few studies of terrestrial species (i.e. insects) using vapor exposure revealed effects of limonene at ppm levels. In the aquatic environment, limonene exhibits high acute toxicity to fish and Daphnia.

14.1.2 Evidence for Carcinogenicity

Evaluation: There is inadequate evidence in humans for the carcinogenicity of d-limonene. There is sufficient evidence in experimental animals for the carcinogenicity of d-limonene. Overall evaluation: In making its overall evaluation of the carcinogenicity to humans of d-limonene, the Working Group concluded that d-limonene produces renal tubular tumors in male rats by a non-DNA reactive alpha-2u-globulin associated response. Therefore, the mechanism by which d-limonene incr the incidence of renal tubular tumors in male rats is not relevant to humans. d-Limonene is not classifiable as to its carcinogenicity to humans (Group 3). /d-Limonene/
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. 73 322 (1999)

14.1.3 Adverse Effects

Neurotoxin - Acute solvent syndrome

Skin Sensitizer - An agent that can induce an allergic reaction in the skin.

14.1.4 Acute Effects

14.1.5 Toxicity Data

LC50 (mice) = 67,500 mg/m3

14.1.6 Interactions

Inhalation of ozone (O3), a highly toxic environmental pollutant, produces airway inflammation and exacerbates asthma. However, in indoor air, O3 reacts with terpenes (cyclic alkenes), leading to formation of airway irritating pollutants. The aim of the study was to examine whether inhalation of the reaction products of O3 and the terpene, limonene, as well as limonene and low-level O3 by themselves, induced allergic sensitization (formation of specific immunoglobulin [Ig] E) and airway inflammation in a subchronic mouse inhalation model in combination with the model allergen ovalbumin (OVA). BALB/cJ mice were exposed exclusively by inhalation for 5 d/wk for 2 wk and thereafter once weekly for 12 wk. Exposures were low-dose OVA in combination with O3, limonene, or limonene/O3 reaction products. OVA alone and OVA + Al(OH)3 served as control groups. Subsequently, all groups were exposed to a high-dose OVA solution on three consecutive days. Serum and bronchoalveolar lavage fluid were collected 24 hr later. Limonene by itself did not promote neither OVA-specific IgE nor leukocyte inflammation. Low-level O3 promoted eosinophilic airway inflammation, but not OVA-specific IgE formation. The reaction products of limonene/O3 promoted allergic (OVA-specific IgE) sensitization, but lung inflammation, which is a characteristic of allergic asthma, was not observed. In conclusion, the study does not support an allergic inflammatory effect attributed to O3-initiated limonene reaction products in the indoor environment.
Hansen JS et al; J Toxicol Environ Health A 76 (19): 1085-95 (2013)
Epidemiological investigations suggest a link between exposure to indoor air chemicals and adverse health effects. Consumer products contain reactive chemicals which can form secondary pollutants which may contribute to these effects. The reaction of limonene and ozone is a well characterized example of this type of indoor air chemistry. The studies described here characterize an in vitro model using an epithelial cell line (A549) or differentiated epithelial tissue (MucilAir). The model is used to investigate adverse effects following exposure to combinations of limonene and ozone. In A549 cells, exposure to both the parent compounds and reaction products resulted in alterations in inflammatory cytokine production. A one hour exposure to limonene+ozone resulted in decreased proliferation when compared to cells exposed to limonene alone. Repeated dose exposures of limonene or limonene+ozone were conducted on MucilAir tissue. No change in proliferation was observed but increases in cytokine production were observed for both the parent compounds and reaction products. Factors such as exposure duration, chemical concentration, and sampling time point were identified to influence result outcome. These findings suggest that exposure to reaction products may produce more severe effects compared to the parent compound.
Anderson SE et al; Toxicol In Vitro 27 (2): 721-30 (2013)
Rauscher murine leukemiavirus infected F344 rat embryo cells were not transformed treated with subeffective doses of 3-methylcholanthrene. These cells treated with limonene showed carcinogenic transformation.
Traul KA et al; J Natl Cancer Inst 66 (1): 171 (1981)
Mouse mammary glands respond to carcinogen stimulus to form mammary lesions in organ culture. In this study it was determined whether the effective chemopreventive agents are active against initiation or the promotion phase of lesion development. Mammary glands were subjected to 24 hr exposure to 2 mg/ml dimethylbenz(a)anthracene followed by a 5 day exposure to 7,12-tetradecanoyl phorbol-13-acetate. This treatment protocol allows the study of initiation and promotion aspects of lesion development. Chemopreventive agents effective when present prior to the carcinogen were considered as anti-initiators, whereas agents effective when present after the dimethylbenz[a]anthracene treatment along with 7,12-tetradecanoyl pherbol-13-acetate were considered as anti-promoters. Within the chemopreventive agents evaluated limonene was an anti-initiator.
Mehta RG, Moon RC; Anticancer Res 11 (2): 593-6 (1991)
For more Interactions (Complete) data for LIMONENE (6 total), please visit the HSDB record page.

14.1.7 Antidote and Emergency Treatment

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Turpentine, terpenes, and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3rd revised edition, Elsevier Mosby, St. Louis, MO 2007, p. 244
Basic treatment: Establish a patent airway (oropharingeal or nasopharingeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. /Turpentine, terpenes, and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3rd revised edition, Elsevier Mosby, St. Louis, MO 2007, p. 244
Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or in respiratory arrest. Positive pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Consider drug therapy for pulmonary edema ... . Treat seizures with diazepam (Valium) or lorazepam (Ativan) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Turpentine, Terpenes, and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3rd revised edition, Elsevier Mosby, St. Louis, MO 2007, p. 245

14.1.8 Human Toxicity Excerpts

/HUMAN EXPOSURE STUDIES/ Dipentene tested /as irritation test/ at 20% in petrolatum produced no irritation after a 48 hr closed patch test in 25 human subjects. A maximization test... was carried out on 25 volunteers. The material was tested at concentration of 20%, in petrolatum and produced no sensitization reactions.
Opdyke, D.L.J. (ed.). Monographs on Fragrance Raw Materials. New York: Pergamon Press, 1979., p. 333
/HUMAN EXPOSURE STUDIES/ Reports of contact allergy to dipentene have appeared. In one investigation, 15 of 22 people with an allergy to oil of turpentine also reacted to dipentene.
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.15 (1998). Available from, as of February 3, 2006: https://www.inchem.org/pages/cicads.html
/HUMAN EXPOSURE STUDIES/ The oxidized forms of the fragrance terpenes limonene and linalool are known to cause allergic contact dermatitis. Significant rates of contact allergy to these fragrances have been reported in European studies and in a recent worldwide study ... /The objective of the study was/ to investigate the prevalence of contact allergy to oxidized limonene and linalool in the U.K. Between 1 August 2011 and 31 December 2012, 4731 consecutive patients in 13 U.K. dermatology departments were tested for hydroperoxides of limonene 0.3% pet., hydroperoxides of linalool 1.0% pet., stabilized limonene 10.0% pet. and stabilized linalool 10.0% pet. Doubtful (?+) and equivocal (+/-) reactions were grouped together as irritant reactions. Two hundred and thirty-seven patients (5.0%) had a positive patch test reaction to hydroperoxides of limonene 0.3% pet. and 281 (5.9%) to hydroperoxides of linalool 1.0% pet. Irritant reactions to one or both oxidized terpenes were found in 242 patients (7.3%). Eleven patients (0.2%) had a positive patch test reaction to the stabilized terpenes alone. This large, multicenter U.K. audit shows a significant rate of allergy to the hydroperoxides of limonene and linalool plus a high rate of irritant reactions. Testing to the oxidized forms alone captures the majority (97.0%; 411 of 422) of positive reactions; testing to nonoxidized terpenes appears to be less useful. We recommend that the hydroperoxides of limonene and linalool be added to an extended baseline patch test series.
Audrain H et al; Br J Dermatol 171 (2): 292-7 (2014)
/HUMAN EXPOSURE STUDIES/ Myoga is a fragrant plant which is the special product of Japan and is cultivated throughout Japan. According to earlier investigation of myoga cultivators in Japan, 8 of 35 cultivators experienced contact dermatitis in the harvest season. The purpose of this study was to assess the allergenicity of myoga and its major volatile components. The volatile components of myoga were analyzed by gas chromatograph (GC). They included alpha-pinene, beta-pinene and R-(+)-limonene. We performed a toxicity study of each of the major fragrant components of myoga using acute dermal irritation assays and the Guinea-Pig Maximization test (GPMT) in order to probe the mechanism of allergic contact dermatitis. In acute dermal irritation assays, alpha-pinene, beta-pinene and limonene showed positive responses at concentrations of 4%; limonene oxide at 20% and myoga showed a positive response at concentrations of 100%. From the results of the GPMT, according to Kligman scores, limonene oxide was identified as an extreme skin sensitizer and myoga as a mild skin sensitizer. The results of the present study show that R-(+)-limonene is the most important allergen amongst the chemical components of myoga, and we consider it to be the reason why myoga cultivators experience allergic contact dermatitis.
Wei Q et al; J Occup Health 48 (6): 480-6 (2006)
For more Human Toxicity Excerpts (Complete) data for LIMONENE (13 total), please visit the HSDB record page.

14.1.9 Non-Human Toxicity Excerpts

/LABORATORY ANIMALS: Acute Exposure/ Increases in hepatic cytochrome P-450 content have been observed in female rats administered limonene (isomer unspecified; 40 mg/kg body weight per day for 3 days) by intraperitoneal injection.
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.12 (1998). Available from, as of February 3, 2006: https://www.inchem.org/pages/cicads.html
/LABORATORY ANIMALS: Acute Exposure/ Limonene / inhibited hepatic HMGCoA (hydroxyl-3-methylglutaryl-CoA) reductase/ when administered intragastrically at 3 mmol/kg to rats.
Clegg RJ et al; Biochem Pharmacol 29 (15): 2125 (1980)
/LABORATORY ANIMALS: Acute Exposure/ Effects observed following the acute exposure of rodents to limonene include increased bile flow at 85 mg/kg body weight, inhibition of S-3-hydroxy-3-methylglutaryl-CoA reductase activity at 409 mg/kg body weight, enzyme induction at 600 and 1200 mg/kg body weight, and decreased motor activity, hypothermia, and potentiation of hexobarbital-induced sleep at 3 mL/kg body weight.
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.12 (1998). Available from, as of February 3, 2006: https://www.inchem.org/pages/cicads.html
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ Administration to dogs at 1.2-3.6 mL/kg/day for 6 months caused frequent vomiting and nausea and decrease in body weight, blood sugar and cholesterol. No significant change observed in organs except in the kidney.
Tsuji M et al; Oyo Yakuri 9 (5): 775 (1975)
For more Non-Human Toxicity Excerpts (Complete) data for LIMONENE (17 total), please visit the HSDB record page.

14.1.10 Non-Human Toxicity Values

LD50 Mouse oral 5.6-6.6 g/kg
DHHS/NTP; Toxicology and Carcinogenesis Studies of d-Limonene (Gavage Studies) p.13 (1990) Technical Rpt Series No. 347, NIH Pub No. 90-2802
LD50 Mouse ip 1.3 g/kg
DHHS/NTP; Toxicology and Carcinogenesis Studies of d-Limonene (Gavage Studies) p.13 (1990) Technical Rpt Series No. 347, NIH Pub No. 90-2802
LD50 Rat oral 5 g/kg bw
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.12 (1998). Available from, as of February 3, 2006: https://www.inchem.org/pages/cicads.html
LD50 Rabbit dermal 5 g/kg bw
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.12 (1998). Available from, as of February 3, 2006: https://www.inchem.org/pages/cicads.html

14.1.11 Ongoing Test Status

EPA has released the first beta version (version 0.5) of the Interactive Chemical Safety for Sustainability (iCSS) Dashboard. The beta version of the iCSS Dashboard provides an interactive tool to explore rapid, automated (or in vitro high-throughput) chemical screening data generated by the Toxicity Forecaster (ToxCast) project and the federal Toxicity Testing in the 21st century (Tox21) collaboration. /The title compound was tested by ToxCast and/or Tox21 assays; Click on the "Chemical Explorer" button on the tool bar to see the data./[USEPA; ICSS Dashboard Application; Available from, as of April 22, 2015: http://actor.epa.gov/dashboard/]

14.2 Ecological Information

14.2.1 EPA Ecotoxicity

Pesticide Ecotoxicity Data from EPA

14.2.2 Ecotoxicity Values

LD50; Species: Colinus virginianus (Bobwhite quail) age 16 weeks; oral >2000 mg/kg
USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on Dipentene (138-86-3). Available from, as of January 19, 2006
LC50; Species: Colinus virginianus (Bobwhite quail) age 10 day; dietary >5620 ppm for 8 days
USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on Dipentene (138-86-3). Available from, as of January 19, 2006
LC50; Species: Colinus virginianus (Bobwhite quail) age 14 days; dietary >5000 ppm for 8 days
USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on Dipentene (138-86-3). Available from, as of January 19, 2006
LC50; Species: Anas platyrhynchos (Mallard duck) age 14 days; dietary >5000 ppm for 8 days
USEPA, Office of Pesticide Programs; Pesticide Ecotoxicity Database (2000) on Dipentene (138-86-3). Available from, as of January 19, 2006
For more Ecotoxicity Values (Complete) data for LIMONENE (10 total), please visit the HSDB record page.

14.2.3 Ecotoxicity Excerpts

/AQUATIC SPECIES/ In the aquatic environment, limonene shows high acute toxicity to fish and Daphnia. Limonene concentrations in surface waters are generally much lower than experimentally determined acute toxicity levels, and therefore it is likely that limonene poses a low risk for acute toxic effects on aquatic organisms.
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.12 (1998). Available from, as of July 7, 2015: https://www.inchem.org/pages/cicads.html
/OTHER TERRESTRIAL SPECIES/ Terrestrial organisms are most likely exposed to limonene via the air. The few studies on terrestrial species (i.e. insects) using vapor exposure revealed effects of limonene at parts per million levels.
International Programme on Chemical Safety; Concise International Chemical Assessment Documents Number 5: Limonene p.12 (1998). Available from, as of July 7, 2015: https://www.inchem.org/pages/cicads.html

14.2.4 Environmental Fate / Exposure Summary

Limonene's production and use in flavorings, fragrances, cosmetics, as a solvent, wetting agent and in the manufacture of resins may result in its release to the environment through various waste streams. Its former use as an insecticide, insect repellant, and dog and cat repellant resulted in its direct release to the environment. Limonene is found in many oils and fruits and is emitted to the environment from plants and the combustion of wood. If released to air, an extrapolated vapor pressure of 1.55 mm Hg at 25 °C indicates limonene will exist solely in the vapor-phase in the ambient atmosphere. Vapor-phase limonene is degraded rapidly in the atmosphere by reaction with photochemically-produced hydroxyl radicals, nitrate radicals and ozone. The half-lives for these reactions are very short, ranging from several minutes to about 2.6 hours. Limonene does not contain chromophores that absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight. If released to soil, limonene is expected to have low mobility based upon an estimated Koc of 1,100. Volatilization from moist soil surfaces is expected to occur given an estimated Henry's Law constant of 0.032 atm-cu m/mole. Volatilization from dry soil surfaces may also occur given the vapor pressure of limonene. Limonene is reported to undergo biodegradation under aerobic conditions, but is resistant to biodegradation under anaerobic conditions. If released to water, limonene is expected to adsorb to suspended solids and sediment in the water column based upon the Koc data. Volatilization from water surfaces is expected to occur rapidly based upon the estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 3 hours and 5 days, respectively. Limonene is not expected to undergo hydrolysis since it lacks functional groups that hydrolyze under environmental conditions. An estimated BCF of 480 suggests the potential for bioconcentration in aquatic organisms is high. Occupational exposure to limonene may occur by inhalation or dermal contact during its production, formulation, transport or use. Exposure to the general population may occur through inhalation of ambient air, ingestion of food, and dermal contact with consumer products containing limonene. (SRC)

14.2.5 Natural Pollution Sources

Limonene is found in many oils and fruits including orange, lemon, grapefruit, berry, leaf, caraway, dill, bergamot, peppermint and spearmint oils(1-4). Limonene emissions to the environment are associated with wax myrtle, sweet acacia, oranges, tomatoes, grasses, and California western sagebrush(5). Emissions of limonene are also associated with balsam poplar, European larche, European fir, Scots pine, Siberian pine, silver fir, common juniper, zeravshan juniper, pencil cedar, evergreen cypress, northern white cedar, chinese arbor vitae, marsh tea and deciduous moss(6).
(1) Fahlbusch K-G et al; Flavors and Fragrances. Ullmann's Encyclopedia of Industrial Chemistry. 7th ed. (1999-2015). New York, NY: John Wiley & Sons. Online Posting Date: 15 Jan 2000
(2) O'Neil MJ, ed; Merck Index, 15th ed, Cambridge, UK: Royal Society of Chemistry p 1021 (2013)
(3) Lewis RJ; Hawley's Condensed Chemical Dictionary. 15th ed. New York, NY: Van Nostrand Reinhold Co., p. 757 (2007)
(4) Altshuller AP; Atmos Environ 17: 2131-65 (1983)
(5) Isidorov VA et al; Atmos Environ 19: 1-8 (1985)
Limonene is widely distributed and occurs naturally in both d- and l- forms(1).
(1) Lewis RJ; Hawley's Condensed Chemical Dictionary. 15th ed. New York, NY: Van Nostrand Reinhold Co., p. 757 (2007)

14.2.6 Artificial Pollution Sources

Limonene's production and use in flavorings, fragrances, cosmetics, as a solvent, wetting agent and in the manufacture of resins(1,2) may result in its release to the environment through various waste streams(SRC). Limonene's former use(2) as an insecticide, insect repellant on humans, and dog and cat repellant(3) resulted in its direct release to the environment(SRC).
(1) Lewis RJ; Hawley's Condensed Chemical Dictionary. 15th ed. New York, NY: Van Nostrand Reinhold Co., p. 757 (2007)
(2) National Pesticide Information Retrieval System's Database on Limonene (138-86-3). Available from, as of April 27, 2015: https://npirspublic.ceris.purdue.edu/ppis/
(3) USEPA/OPPTS; R.E.D Facts. Limonene (138-86-3). Reregistration Eligibility Decisions (REDs) Database. EPA-738-F-94-030. Sept 1994. Available from, as of Apr 24, 2015: https://www.epa.gov/pesticides/reregistration/status.htm

14.2.7 Environmental Fate

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1,100 determined from a structure estimation method(2), indicates that limonene is expected to have low mobility in soil(SRC). Volatilization from moist soil surfaces is expected to occur based on an estimated Henry's Law constant of 0.032 atm-cu m/mole(SRC) derived from its extrapolated vapor pressure, 1.55 mm Hg(3), and water solubility, 7.57 mg/L(4). Volatilization from dry soil surfaces may occur given the vapor pressure of this compound(3). Limonene is reported to undergo biodegradation under aerobic conditions, but is resistant to biodegradation under anaerobic conditions(5). Terpene acclimated inocula prepared from soil obtained from a coniferous forest and hardwood forest in North Carolina degraded limonene with a half-life of approximately 9-20 hours at 23 °C following a lag period of 15-23 hours(6).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Apr 24, 2015: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Boublik T et al; The vapor pressures of pure substances. Vol. 17. Amsterdam, Netherlands: Elsevier Sci. Publ. (1984)
(4) Miller DJ, Hawthorne SB; J Chem Eng Data 44: 315-8 (2000)
(5) WHO; International Programme on Chemical Safety Concise International Chemical Assessment Document No. 5. Limonene ISBN 92 4 153005 7 (1998)
(6) Misra G et al; Appl Microbiol Biotechnol 45: 831-8 (1996)
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1,100 determined from a structure estimation method(2), indicates that limonene is expected to adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 0.032 atm-cu m/mole(SRC) derived from its extrapolated vapor pressure, 1.55 mm Hg(4), and water solubility, 7.57 mg/L(5). Volatilization half-lives for a model river and model lake are 3 hours and 5 days, respectively(SRC). According to a classification scheme(6), an estimated BCF of 660(SRC), from a log Kow of 4.57(7), and a regression derived equation(2), suggests the potential for bioconcentration in aquatic organisms is high(SRC). Limonene is reported to undergo biodegradation under aerobic conditions (73% of its theoretical BOD in 2 weeks in Japanese MITI test(8)), but is resistant to biodegradation under anaerobic conditions(9).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Apr 24, 2015: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 4-9, 5-4, 5-10, 15-1 to 15-29 (1990)
(4) Boublik T et al; The vapor pressures of pure substances. Vol. 17. Amsterdam, Netherlands: Elsevier Sci Publ (1984)
(5) Miller DJ, Hawthorne SB; J Chem Eng Data 44: 315-318 (2000)
(6) Franke C et al; Chemosphere 29: 1501-14 (1994)
(7) Li J, Perdue EM; Physicochemical properties of selected monoterpenes. Preprints of papers presented at the 209th ACS National Meeting Anaheim, CA April 2-7, 35: 134-7 (1995)
(8) NITE; Chemical Risk Information Platform (CHRIP). Biodegradation and Bioconcentration. Tokyo, Japan: Natl Inst Tech Eval. Available from, as of Apr 24, 2015: https://www.safe.nite.go.jp/english/db.html
(9) WHO; International Programme on Chemical Safety Concise International Chemical Assessment Document No. 5. Limonene. ISBN 92 4 153005 7 (1998)
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), limonene, which has an extrapolated vapor pressure of 1.55 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase limonene is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals, nitrate radicals and ozone(SRC). The half-life for the reaction with hydroxyl radicals is estimated to be 2.6 hours(SRC) from its rate constant of 1.49X10-10 cu cm/molecule-sec at 25 °C(3). The half-life for the reaction with ozone is estimated to be 0.5 hours(SRC) from its rate constant of 6.5X10-16 cu cm/molecule-sec(4). The calculated nighttime lifetime for the reaction of limonene with nitrate radicals is 9 minutes(5). Limonene does not contain chromophores that absorb at wavelengths >290 nm(6) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988)
(2) Boublik T et al; The vapor pressures of pure substances. Vol. 17. Amsterdam, Netherlands: Elsevier Sci Publ (1984)
(3) Winer AM et al; J Phys Chem: 80: 1635-9 (1976)
(4) Atkinson R; Chem Rev 85: 69-201 (1985)
(5) Winer AM et al; Science 224: 156-9 (1984)
(6) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 8-12 (1990)

14.2.8 Environmental Biodegradation

AEROBIC: Organisms isolated from soil and water were unable to oxidize limonene in laboratory experiments(1). Limonene was listed as a compound difficult to biodegrade and was classified in level 3 (difficult to biodegrade) in a 5 tiered rating system on ease of biodegradability(2). The concentration of limonene between the influent and effluent of aerated treatment lagoons was found to decrease significantly which the author ascribed to a biological removal process although complete documentation was not provided(3). Other studies have indicated that limonene is readily biodegradable under aerobic conditions. Limonene, present at 100 mg/L, reached 73% of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(4). Terpene-acclimated inocula prepared from soil obtained from a coniferous forest and hardwood forest in North Carolina degraded limonene with a half-life of approximately 9-20 hours at 23 °C following a lag period of 15-23 hours(5). Degradation by unacclimated inocula did not begin until after a 182-hour lag period(5).
(1) Perry JJ; The role of Co-Oxidation and Commensalism in the Biodegradation of Recalcitrant Molecules. US Army Res Off DAAG-29-76-G0159 (1980)
(2) Abrams EF et al; Identification of Organic Compounds in Effluents from Industrial Sources. Washington, DC: USEPA-560/3-75-002 (1975)
(3) Wilson D, Hrutfiord B; Pulp and Paper Canada 76: 91-3 (1975)
(4) NITE; Chemical Risk Information Platform (CHRIP). Biodegradation and Bioconcentration. Tokyo, Japan: Natl Inst Tech Eval. Available from, as of Apr 24, 2015: https://www.safe.nite.go.jp/english/db.html
(5) Misra G et al; Appl Microbiol Biotechnol 45: 831-8 (1996)
ANAEROBIC: Limonene is reported to undergo biodegradation under aerobic conditions, but is resistant to biodegradation under anaerobic conditions(1). In a test on methanogenic degradation (batch bioassay inoculated with granular sludge, maintained at 30 °C), there was no indication of any metabolism of limonene, possibly because of toxicity to the microorganisms(1).
(1) WHO; International Programme on Chemical Safety Concise International Chemical Assessment Document No. 5. Limonene. ISBN 92 4 153005 7 (1998)

14.2.9 Environmental Abiotic Degradation

The rate constant for the vapor-phase reaction of limonene with photochemically-produced hydroxyl radicals has been measured as 1.49X10-10 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 2.6 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of limonene with ozone has been measured as 6.5X10-16 cu cm/molecule-sec at 25 °C(2). This corresponds to an atmospheric half-life of about 0.5 hours at an atmospheric concentration of 7X10+11 molecules per cu cm(2). The calculated nighttime lifetime for the reaction of limonene with nitrate radicals is 9 minutes(3). Reaction products include endolin; possible products include limonene-1,2-dinitrate amd 8-nitroperoxylimonene-9-nitrate(4). Photolysis of limonene in the presence of nitrogen oxides produces formaldehyde, formic acid, carbon monoxide, carbon dioxide, acetaldehyde, peroxyacetyl nitrate and acetone(5). Limonene is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(6). Limonene does not contain chromophores that absorb at wavelengths >290 nm(6) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Winer AM et al; J Phys Chem 80: 1635-9 (1976)
(2) Atkinson R; Chem Rev 85: 69-201 (1985)
(3) Winer AM et al; Science 224: 156-9 (1984)
(4) Spittler M et al; Atmos Environ 40: S116-S127 (2006)
(5) Darnall KR et al; Environ Sci Tech 10: 692-6 (1976)
(6) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 7-5, 8-12 (1990)

14.2.10 Environmental Bioconcentration

An estimated BCF of 480 was calculated for limonene(SRC), using a log Kow of 4.57(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is high, provided the compound is not metabolized by the organism(SRC).
(1) Li J, Perdue EM; Physicochemical properties of selected monoterpenes. Preprints of papers presented at the 209th ACS National Meeting Anaheim, CA April 2-7, 35(1): 134-7 (1995)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Apr 24, 2015:
(3) Franke C et al; Chemosphere 29: 1501-14 (1994) https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm/

14.2.11 Soil Adsorption / Mobility

Using a structure estimation method based on molecular connectivity indices(1), the Koc for limonene can be estimated to be 1,100(SRC). According to a classification scheme(2), this estimated Koc value suggests that limonene is expected to have low mobility in soil(SRC).
(1) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Apr 24, 2015: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(2) Swann RL et al; Res Rev 85: 17-28 (1983)

14.2.12 Volatilization from Water / Soil

The Henry's Law constant for limonene is estimated as 0.032 atm-cu m/mole(SRC) derived from its vapor pressure, 1.55 mm Hg(1), and water solubility, 7.57 mg/L(2). This Henry's Law constant indicates that limonene is expected to volatilize rapidly from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 3 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 5 days(SRC). Limonene's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of limonene from dry soil surfaces may exist(SRC) based upon its vapor pressure(1).
(1) Boublik T et al; The vapor pressures of pure substances. Vol. 17. Amsterdam, Netherlands: Elsevier Sci Publ (1984)
(2) Miller DJ, Hawthorne SB; J Chem Eng Data 44: 315-8 (2000)
(3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15-29 (1990)

14.2.13 Environmental Water Concentrations

GROUNDWATER: Limonene was detected in contaminated groundwater in The Netherlands at a maximum concentration of 10 ug/L(1). Limonene was detected in 11 of 11 ground water samples at the site of a former pine tar manufacturer in Gainesville, FL, at concentration ranging from 1 ug/L to 130 ug/L(2).
(1) Zoeteman BCJ et al; Sci Total Environ 21: 187-202 (1981)
(2) McCreary JJ et al; Chemosphere 12: 1619-32 (1983)
DRINKING WATER: Limonene was listed as a compound identified in U.S. drinking water supplies(1-3). It was qualitatively detected in treated drinking water supplies in the U.K., 1976(4).
(1) Kopfler FC et al; Adv Environ Sci Technol 8: 419-33 (1977)
(2) Kool HJ et al; CRC Crit Rev Env Control 12: 307-57 (1982)
(3) Abrams EF et al; Identification of Organic Compounds in Effluents from Industrial Sources Washington, DC: USEPA-560/3-75-002 (1975)
(4) Fielding M et al; Organic Micropollutants in Drinking Water TR-159 Medmenham, Eng Water Res Cent 49 pp. (1981)
SURFACE WATER: The concentration of limonene in seawater samples from Resurrection Bay, AK, was 84 ng/L in June 1985 and 0.47 ng/L in June, 1986(1). Limonene has been qualitatively detected in the Black Warrior River, near Tuscaloosa, AL, 1975(2). Limonene was identified, but not quantified, in the River Glatt, Switzerland, 1975(3), and in water samples taken from the River Lee, in the UK, date not provided(4).
(1) Button DK, Juttner F; Marine Chem 26: 57-66 (1989)
(2) Bertsch W et al; J Chromatog 112: 701-18 (1975)
(3) Zurcher F, Giger W; Vom Wasser 47: 37-55 (1976)
(4) Waggott A et al; Chem Water Reuse 2: 55-9 (1981)
RAIN/SNOW: Limonene was detected in snow samples from Finland at concentrations of 0.15 and 0.16 ug/kg(1).
(1) Poliakova OV et al; Toxicol Environ Chem 75: 181-194 (2000)

14.2.14 Effluent Concentrations

Limonene was detected as a component of landfill gases from sites in the UK at measured concentrations of 21-84 mg/cu m in probes buried underground and 7.4 mg/cu m at above ground vents(1). Limonene was qualitatively detected in 2 of 46 U.S. industrial effluent samples(2). Limonene was detected in 6 of 7 samples of kraft pulp mill wastewater at concentrations ranging from 10-220 ppb in 2 Canadian mills monitored in 1973(3). Limonene was identified, not quantified, in landfill leachate(4). Limonene was qualitatively identified in the effluent gas from refuse waste obtained from a food center in an experiment designed to determine the gases emitted from decaying waste matter at refuse sites, landfills, and trash transfer sites(5). Limonene has been associated with effluent from the following industries: extraction of pine gum, paper and pulp mills, plastics materials-synthetic resins and non vulcanizable elastomers, perfumes, cosmetics and other toilet preparations, organic solvents and lubricating oils and greases(6).
(1) Young P, Parker A; pp. 24-41 Hazardous and Industrial Waste Management and Testing 3rd Symp Amer Soc Test Mater (1984)
(2) Bursey JT, Pellizzari ED; Analysis of Industrial Wastewater for Organic Pollutants in Consent Degree Survey. Res Triangle Park, NC: USEPA (1982)
(3) Wilson D, Hrutfiord B; Pulp and Paper Canada 76: 91-3 (1975)
(4) Venkataramani ES, Ahlert RC; J Water Purif Contr Fed 56: 1178-84 (1984)
(5) Koe LC, Ng WJ; Water, Air Soil Pollut 33: 199-204 (1987)
(6) Abrams EF et al; Identification of Organic Compounds in Effluents from Industrial Sources Washington, DC: USEPA-560/3-75-002 (1975)

14.2.15 Sediment / Soil Concentrations

SOIL: Limonene was detected in soil samples at the site of a former pine-tar manufacturer in Gainesville, FL, at a concentration ranging from not detected to 920 ug/g(1).
(1) McCreary JJ et al; Chemosphere 12: 1619-32 (1983)

SOIL: Limonene concentrations at 30, 50, and 70 cm soil depths at the Case Passerini landfill in Florence, Italy. Concentrations in 2 gas recovery wells were <2 ppbV(1).

Table: Concentrations (ppbV)

Sample No.
1
30 cm depth
266
50 cm depth
180
70 cm depth
16
Sample No.
2
30 cm depth
656
50 cm depth
605
70 cm depth
410
Sample No.
3
30 cm depth
200
50 cm depth
249
70 cm depth
352
Sample No.
4
30 cm depth
48
50 cm depth
22
70 cm depth
241
Sample No.
5
30 cm depth
201
50 cm depth
30
70 cm depth
219

(1) Tassi F et al; Sci Total Environ 407(15): 4513-25 (2009)
SEDIMENT: Limonene was identified, not quantified, in sediment samples obtained from the German Bight(1).
(1) Schwarzbauer J et al; Org Geochem 31: 1713-1731 (2000)

14.2.16 Atmospheric Concentrations

URBAN/SUBURBAN: Limonene was listed as a compound typically identified in both indoor and outdoor air(1). Limonene was detected in 97% of 17 indoor air samples taken at residences in Ruston, WA, 1985-6, at a concentration ranging from 1.6 to 78 ug/cu m (mean and median 18 ug/cu m and 11 ug/cu m, respectively), outdoor concentrations were typically an order of magnitude lower(2). Limonene was identified, not quantified, in 37 indoor and 12 outdoor samples from 36 houses (50 total measurements) in Chicago, IL(3). The concentration of limonene in the air above Moscow Mountain, ID, 1976-1977, ranged from <10 to 50 parts per trillion(4). The mean and maximum concentration of limonene in 40 homes in Oak Ridge/Knoxville, TN, 1982-3, was 16 ug/cu m and 77.5 ug/cu m, respectively(5). The concentration of limonene in Houston, TX, ranged from not detected to 5.7 ppb(6). Limonene was detected indoors in an office building, 1987, at a concentration ranging 43-63 ug/cu m(7).
(1) Harrison RM et al; Environ Tech Lett 9: 521-30 (1988)
(2) Montgomery DD; Kalman DA; Appl Ind Hyg 4: 17-20 (1989)
(3) Jarke FH et al; Ashrae Trans 87: 153-6 (1981)
(4) Holdren MW et al; J Geophys Res 84: 5083-8 (1979)
(5) Hawthorne AR et al; pp. 574-26 in Spec Meas Monit Non-Criter Contam. Frederick ER, ed. Pittsburgh, PA: APCA (1983)
(6) Bertsch W et al; J Chromatog Sci 12: 175-82 (1974)
(7) Weschler CJ et al; Am Ind Hyg Assoc J 51: 261-8 (1990)
URBAN/SUBURBAN: Limonene was qualitatively detected in the air of Leningrad, Russia 1976, and 5 other Russian cities(1,2). Limonene was detected in suburban air samples in Germany, 1985, at concentrations ranging from not detected-2.0 ng/cu m(3,4). Limonene was detected in outdoor air in Northern Italy, 1983-8, at a mean concentration of 2 ug/cu m(5).
(1) Ioffe BV et al; J Chromatog 142: 787-95 (1977)
(2) Ioffe BV et al; Environ Sci Technol 13: 864-9 (1979)
(3) Juttner F; Chemosphere 17: 309-17 (1988)
(4) Juttner F; Chemosphere 15: 985-92 (1986)
(5) DeBortoli M et al; Environ Int 12: 343-50 (1986)
INDOOR: Limonene was qualitatively detected in air samples taken at 2 Stockholm preschools, 1981-1982(1). Limonene was detected in indoor air of apartments and homes in Northern Italy, 1983-8, at mean a concentration of 140 ug/cu m(2).
(1) Noma E et al; Atmos Environ 22: 451-60 (1988)
(2) DeBortoli M et al; Environ Int 12: 343-50 (1986)
INDOOR: Limonene was detected in 97% of 17 indoor air samples taken at residences in Ruston, WA, 1985-6, at a concentration ranging from 1.6 to 78 ug/cu m (mean and median 18 ug/cu m and 11 ug/cu m, respectively); outdoor concentrations were typically an order of magnitude lower(1).
(1) Montgomery DD; Kalman DA; Appl Ind Hyg 4: 17-20 (1989)
(2) Jarke FH et al; Ashrae Trans 87: 153-6 (1981)
RURAL/REMOTE: The concentrations of limonene and other monoterpenes in air vary considerably. Recorded concentrations in rural areas depend on many factors, such as the type of vegetation, temperature, time of the day, and time of the year(1). The concentration of limonene in the air above Moscow Mountain, ID, 1976-1977, ranged from <10 to 50 parts per trillion(3). The concentration of limonene in the air over a forest in the Republic of Georgia, July, 1979, ranged from 0.004 ug/cu m to 0.010 ug/cu m in 8 samples(3). The concentration of limonene 1.7 m above a maple forest in Quebec ranged from approximately 100-1750 parts per trillion over a two day period in June, 1989(4). Limonene was detected in forest air samples in Southern Black Forest region, Germany, 1985, at concentrations ranging from 1.0-89 ng/cu m(5,6). Traces of limonene were found in the air over the Landes Forest, France, 1984, which consists mainly of maritime pines(7).
(1) WHO; International Programme on Chemical Safety Concise International Chemical Assessment Document No. 5. Limonene. ISBN 92 4 153005 7 (1998)
(2) Holdren MW et al; J Geophys Res 84: 5083-8 (1979)
(3) Shaw RWJR et al; Environ Sci Tech 17: 389-95 (1983)
(4) Clement B et al; Atmos Environ 24A: 2513-6 (1990)
(5) Juttner F; Chemosphere 17: 309-17 (1988)
(6) Juttner F; Chemosphere 15: 985-92 (1986)
(7) Riba ML et al; Atmos Environ 21: 191-3 (1987)

14.2.17 Food Survey Values

Limonene (unspecified isomer) has been identified as a volatile component of fried chicken(1), chickpea seed (Cicer arietinum)(2), orange juice essence(3), mangos(4), roasted filberts (Corylus avellana)(5), Beaufort (Gruyere) cheese manufactured in the area of the French Alps(6) and Udaho Russet Burbank baked potatoes(7). It has been detected in a headspace analysis of intact, tree ripened nectarines, but not in an analysis of the blended fruit(8). Limonene was present at 0.62 and 0.21 nL/L in emissions from cereal silage and high-moisture ground corn, respectively, on farms sampled in California's San Joaquin Valley(9).
(1) Tang J et al; J Agric Food Chem 31: 1287-92 (1983)
(2) Rembold H et al; J Agric Food Chem 37: 659-62 (1989)
(3) Moshonas MG, Shaw PE; J Agric Food Chem 38: 2181-4 (1990)
(4) MacLeod AJ, Snyder CH; J Agric Food Chem 36: 137-9 (1988)
(5) Kinlin TE et al; J Agr Food Chem 20: 1021-8 (1972)
(6) Dumont JP, Adda J; J Agr Food Chem 26: 364-7 (1978)
(7) Coleman EC et al; J Agric Food Chem 29: 42-8 (1981)
(8) Takeoka GR et al; J Agric Food Chem 36: 553-60 (1988)
(9) Malkina IL et al; J Environ Qual 40: 28-36 (2011)

14.2.18 Plant Concentrations

The flux of combined limonene and beta-phellandrene from a red pine (Pinus densiflora) forest in Japan was measured from May-November 2000(1). The largest values observed were in June with an average flux rate of 1.1 nmol/sq m-sec(1). The measured average emission rate of alpha-pinene and limonene in eucalyptus (Eucalyptus spp) was reported as 3.25 ug/g-hour(2). Limonene emission concentrations were 18, 10, 9, 17 nmol/sq m-min from Eucalyptus camaldulensis, E globulus, E grandis and E viminalis, respectively, in southern Australia(3). Estimated limonene emissions were 40.7, 98.9, 173.9, and 41.5 ug/sq m-hr for broadleaf trees, needle leaf trees, shrubs and bushes, and grasses and crops, respectively, for the United States were between July 2001 and January 2002(4).
(1) Tani A et al; Atmos Environ 36: 3391-3402 (2002)
(2) He C et al; Chemosphere 2: 65-76 (2000)
(3) Winters AJ et al; Atmos Environ 43: 3035-43 (2009)
(4) Sakulyanontvittaya T et al; Environ Sci Technol 42: 1623-29 (2008)

Limonene concentrations in plants(1).

Table: Top 40 Plants

Genus species
Citrus limon
Family
Rutaceae
Common name
Lemon
Part
Paricarp essential oil
Concn (ppm)
774,000
Genus species
Apium graveolens
Family
Apiaceae
Common name
Celery
Part
Fruit essential oil; ET
Concn (ppm)
754,000; 695,000
Genus species
Canarium indicum
Family
Busaraceae
Common name
Java olive
Part
Essential oil
Concn (ppm)
135,250
Genus species
Apium graveolens
Family
Apiaceae
Common name
Celery
Part
Root essential oil
Concn (ppm)
117,000
Genus species
Carum carvi
Family
Apiaceae
Common name
Caraway
Part
Fruit
Concn (ppm)
30,180
Genus species
Apium graveolens
Family
Apiaceae
Common name
Celery
Part
Seed
Concn (ppm)
24,000
Genus species
Pycnanthemum virginianum
Family
Lamiaceae
Common name
Virginia mountain mint
Part
Shoot
Concn (ppm)
14,674
Genus species
Pycanthemum clinopodiodes
Family
Lamiaceae
Common name
Clinopod mountain mint
Part
Shoot
Concn (ppm)
10,780
Genus species
Citrus sinensis
Family
Rutaceae
Common name
Orange
Part
Fruit
Concn (ppm)
9,700
Genus species
Elettaria cardamomum
Family
Zingiberaceae
Common name
Cardamom
Part
Fruit
Concn (ppm)
9,481
Genus species
Foeniculum vulgare
Family
Apiaceae
Common name
Fennel
Part
Fruit
Concn (ppm)
9,420
Genus species
Citrus reticulata
Family
Rutaceae
Common name
Mandarin
Part
Fruit
Concn (ppm)
9,400
Genus species
Mentha spicata
Family
Lamiaceae
Common name
Spearmint
Part
Plant
Concn (ppm)
9,075
Genus species
Pycanthemum tenuifolium
Family
Lamiaceae
Common name
Slenderleaf mountain mint
Part
Shoot
Concn (ppm)
8,520
Genus species
Citrus aurantium
Family
Rutaceae
Common name
Bitter orange
Part
Plant
Concn (ppm)
8,000
Genus species
Citrus limon
Family
Rutaceae
Common name
Lemon
Part
Essential oil
Concn (ppm)
8,000
Genus species
Citrus aurantiifolia
Family
Rutaceae
Common name
Lime
Part
Fruit
Concn (ppm)
7,500
Genus species
Zea mays
Family
Poaceae
Common name
Corn
Part
Silk essential oil
Concn (ppm)
7,000
Genus species
Pimenta racemosa
Family
Myrtaceae
Common name
Bayrum tree
Part
Leaf
Concn (ppm)
6,870
Genus species
Pycanthemum pycanthemoides
Family
Lamiaceae
Common name
Typical mountain mint
Part
Shoot
Concn (ppm)
5,800
Genus species
Myristica fragrans
Family
Myristicaceae
Common name
Mace
Part
Seed
Concn (ppm)
5,760
Genus species
Pycnanthemum albescens
Family
Lamiaceae
Common name
White mountain mint
Part
Shoot
Concn (ppm)
5,697
Genus species
Illicium verum
Family
Illiciaceae
Common name
Chinese star anise
Part
Fruit
Concn (ppm)
5,220
Genus species
Thymus vulgaris
Family
Lamiaceae
Common name
Common thyme
Part
Plant
Concn (ppm)
5,200
Genus species
Monarda punctata
Family
Lamiaceae
Common name
Horsemint
Part
Plant
Concn (ppm)
2,874
Genus species
Pycanthemum loomisii
Family
Lamiaceae
Common name
Loomis mountain mint
Part
Shoot
Concn (ppm)
2,520
Genus species
Agastache urticifolia
Family
Lamiaceae
Common name
Nettle-leaf giant hyssop
Part
Plant
Concn (ppm)
2,464
Genus species
Saliva officinalis
Family
Lamiaceae
Common name
Sage
Part
Plant
Concn (ppm)
2,380
Genus species
Pilocarpus jaborandi
Family
Rutaceae
Common name
Indian hemp
Part
Leaf
Concn (ppm)
2,350
Genus species
Pycanthemum curvipes
Family
Lamiaceare
Common name
Curver mountain mint
Part
Shoot
Concn (ppm)
2,323
Genus species
Curcuma longa
Family
Zingiberaceae
Common name
Indian saffron
Part
Essential oil
Concn (ppm)
2,300
Genus species
Mentha pulegium
Family
Lamiaceae
Common name
European pennyroyal
Part
Plant
Concn (ppm)
2,200
Genus species
Trachyspermum ammi
Family
Apiaceae
Common name
Ajwan
Part
Fruit
Concn (ppm)
2,040
Genus species
Rosmarinus officinalis
Family
Lamiaceae
Common name
Rosemary
Part
Plant
Concn (ppm)
1,950
Genus species
Foeniculum vulgare
Family
Apiaceae
Common name
Fennel
Part
Plant
Concn (ppm)
1,800
Genus species
Abies balsamea
Family
Pinaceae
Common name
Balsam fir
Part
Plant
Concn (ppm)
1,800
Genus species
Satureja douglasii
Family
Lamiaceae
Common name
Douglas savory
Part
Plant
Concn (ppm)
1,508
Genus species
Daucus carota
Family
Apiaceae
Common name
Carrot
Part
Seed
Concn (ppm)
1,500
Genus species
Monarda media
Family
Lamiaceae
Common name
Mean monarda
Part
Plant
Concn (ppm)
1,484
Genus species
Petroselinum crispum
Family
Apiaceae
Common name
Parsley
Part
Seed
Concn (ppm)
1,470
Genus species
Eucalyptus citriodora
Family
Myrtaceae
Common name
Lemon eucalyptus
Part
Leaf
Concn (ppm)
1,420

(1) USDA; Dr. Duke's Phytochemical and Ethnobotanical Databases. Plants with a chosen chemical. Limonene. Washington, DC: US Dept Agric, Agric Res Service. Available from, as of Apr 23, 2015: https://www.ars-grin.gov/duke/

14.2.19 Fish / Seafood Concentrations

Limonene (unspecified isomer) was detected in the leg, body, and carapace of crabs (Charybdis feriatus) at average concentrations of 2.0, 1.1, and 7.6 ug/kg, respectively(1).
(1) Chung HY; J Agric Food Chem 47: 2280-2287 (1999)

14.2.20 Milk Concentrations

EXPERIMENTAL: Limonene was qualitatively detected in 8 of 8 samples of mother's milk obtained from residents of urban centers in PA, NJ, and LA(1). Limonene was detected not quantified in fish oil-enriched milk for up to 14 days storage at 2 °C(2).
(1) Pellizzari ED et al; Bull Environ Contam Toxicol 28: 322-8 (1982)
(2) Venkateshwarlu G, et al; J Agric Food Chem 52: 311-17 (2004)

14.2.21 Other Environmental Concentrations

Limonene was detected at a cumulative emission concentration of 7,000 ug/dry kg-hr in the emissions released from aerobic degradation of orange wastes over a period of 60 days(1). The compound has been detected in tobacco, tobacco smoke and tobacco smoke substitute(2). Limonene was present in 23 of 25 consumer fragrance products tested(3). Limonene was present at 0.62 and 0.21 nL/L in emissions from cereal silage and high-moisture ground corn, respectively, on farms sampled in California's San Joaquin Valley(4).
(1) Wang X, Wu T; Environ Sci Technol 42(3): 3265-70 (2008)
(2) Rodgman A, Perfetti TA; The Chemical Components of Tobacco and Tobacco Smoke 2nd, ed., Baco Raton, FL: CRC Press p. 1403 (2013)
(3) Steinemann AC et al; Environ Impact Assess Rev 31(3): 311-33 (2011)
(4) Malkina IL et al; J Environ Qual 40: 28-36 (2011)
Limonene was identified in the emissions of wood burning fireplaces(1). Limonene emission rates from residential burning of southern-European woods were as follows(2):
Genus species
Fagus sylvantica
Common name
European beech
Woodstove (mg/kg fuel burned dry basis)
below detection limit
Fireplace (mg/kg fuel burned dry basis)
0.399
Genus species
Quercus pyrenaica
Common name
Pyrenean oak
Woodstove (mg/kg fuel burned dry basis)
0.855
Fireplace (mg/kg fuel burned dry basis)
0.967
Genus species
Populus nigra
Common name
Black poplar
Woodstove (mg/kg fuel burned dry basis)
0.207
Fireplace (mg/kg fuel burned dry basis)
0.631
Genus species
US hardwood
Common name
unspecified
Woodstove (mg/kg fuel burned dry basis)
0.06
Fireplace (mg/kg fuel burned dry basis)
2.89
Genus species
US softwood
Common name
unspecified
Woodstove (mg/kg fuel burned dry basis)
35.4
(1) Purvis CR et al; Environ Sci Technol 34: 1653-8 (2000)
(2) Evtyugina M et al; Atmos Environ 83: 90-8 (2014)

14.2.22 Probable Routes of Human Exposure

According to the 2012 TSCA Inventory Update Reporting data, 4 reporting facilities estimate the number of persons reasonably likely to be exposed during the manufacturing, processing, or use of limonene in the United States may be as low as 50 workers and as high as 99 workers per plant; the data may be greatly underestimated due to confidential business information (CBI) or unknown values(1).
(1) US EPA; Chemical Data Reporting (CDR). Non-confidential 2012 Chemical Data Reporting information on chemical production and use in the United States. Available from, as of Apr 24, 2015: https://www.epa.gov/cdr/pubs/guidance/cdr_factsheets.html
NIOSH (NOES Survey 1981-1983) has statistically estimated that 185,336 workers (45,650 of these are female) were potentially exposed to limonene in the US(1). The NOES Survey does not include farm workers. Occupational exposure to limonene may occur through inhalation and dermal contact with this compound at workplaces where limonene is produced or used. Monitoring data indicate that the general population may be exposed to limonene via inhalation of ambient air, ingestion of food and drinking water, and dermal contact with this consumer products containing limonene(SRC).
(1) NIOSH; NOES. National Occupational Exposure Survey conducted from 1981-1983. Estimated numbers of employees potentially exposed to specific agents by 2-digit standard industrial classification (SIC). Available from, as of Apr 24, 2015: https://www.cdc.gov/noes/
Occupational exposure to limonene may occur by inhalation or dermal contact during its production, formulation, transport or use. Exposure to the general population may occur by inhalation due to its presence in the atmosphere as a result of its release from natural sources(1,2), its presence in household products, or by ingestion of food in which it occurs either naturally or has been added as a flavor or fragrance(SRC).
(1) Isidorov VA et al; Atmos Environ 19: 1-8 (1985)
(2) Altshuller AP; Atmos Environ 17: 2131-65 (1983)
(3) Tichenor BA, Mason MA; JAPCA 38: 264-8 (1988)
(4) Tichenor BA; Organic Emission Measurements via Small Chamber Testing. USEPA, Research Triangle Park, NC. PB87-199154 (1987)
Limonene was detected in the air of the vulcanization area of a shoe-sole factory at a concentration of 25-130 ug/cu m, and at 5-1700 ug/cu m in the vulcanization area of a tire retreading factory(1). Limonene was detected indoors in an office building, 1987, at a concentration ranging from 43-63 ug/cu m(2). Limonene was qualitatively detected in air samples taken at 2 Stockholm preschools, 1981-2(3). Limonene was detected in the workplace air of 3 photocopying centers at levels of 0.1 to 2.0 ppb, with average values of 0.3-0.9 ppb in the breathing zone(4). Limonene is an active ingredient in several registered shampoo, dip and spray products applied to domestic animals to control fleas and ticks(5).
(1) Cocheo V et al; Am Ind Hyg Assoc J 44: 521-7 (1983)
(2) Weschler CJ et al; Am Ind Hyg Assoc J 51: 261-8 (1990)
(3) Noma E et al; Atmos Environ 22: 451-60 (1988)
(4) Stefaniak AB et al; Environ Res 83: 162-73 (2000)
(5) USEPA/OPPTS; R.E.D Facts. Limonene (138-86-3). Reregistration Eligibility Decisions (REDs) Database. EPA-738-F-94-030. Sept 1994. Available from, as of Apr 24, 2015: https://www.epa.gov/pesticides/reregistration/status.htm

14.2.23 Average Daily Intake

The intake of limonene in food varies due to differing diet patterns. Based on daily US consumption of limonene per capita, the intake of limonene from food for the general population was estimated to be 0.27 mg/kg body weight per day(1). The intake of limonene from indoor and outdoor air for the general population is estimated to be 10 and 0.1 ug/kg body weight per day, respectively(1). The average exposure range of residents in Flemish homes for the elderly was 5.58-29.92 ppm/min corresponding to an uptake rate of 27 mL/min, sampled from 2007 through 2009 (2).
(1) WHO; International Programme on Chemical Safety Concise International Chemical Assessment Document No. 5. Limonene. ISBN 92 4 153005 7 (1998)
(2) Walgraeve C et al; Atmos Environ 45(32): 5828-36 (2011)

14.2.24 Body Burden

Limonene has been identified in the expired air of a selected urban population of normal, healthy, non-smoking volunteers(1). Limonene was qualitatively detected in 8 of 8 samples of mother's milk obtained from residents of urban centers in PA, NJ, and LA(2).
(1) Krotoszynski B et al; J Chromat Sci 15: 239-44 (1977)
(2) Pellizzari ED et al; Bull Environ Contam Toxicol 28: 322-8 (1982)

15 Associated Disorders and Diseases

Associated Occupational Diseases with Exposure to the Compound

Solvents, acute toxic effect [Category: Acute Poisoning]

Contact dermatitis, allergic [Category: Skin Disease]

16 Literature

16.1 Consolidated References

16.2 NLM Curated PubMed Citations

16.3 Springer Nature References

16.4 Thieme References

16.5 Wiley References

16.6 Nature Journal References

16.7 Chemical Co-Occurrences in Literature

16.8 Chemical-Gene Co-Occurrences in Literature

16.9 Chemical-Disease Co-Occurrences in Literature

17 Patents

17.1 Depositor-Supplied Patent Identifiers

17.2 WIPO PATENTSCOPE

17.3 Chemical Co-Occurrences in Patents

17.4 Chemical-Disease Co-Occurrences in Patents

17.5 Chemical-Gene Co-Occurrences in Patents

18 Biological Test Results

18.1 BioAssay Results

19 Taxonomy

The LOTUS Initiative for Open Natural Products Research: frozen dataset union wikidata (with metadata) | DOI:10.5281/zenodo.5794106

20 Classification

20.1 MeSH Tree

20.2 NCI Thesaurus Tree

20.3 ChEBI Ontology

20.4 KEGG: Lipid

20.5 KEGG: Phytochemical Compounds

20.6 ChemIDplus

20.7 CAMEO Chemicals

20.8 UN GHS Classification

20.9 EPA CPDat Classification

20.10 NORMAN Suspect List Exchange Classification

20.11 EPA DSSTox Classification

20.12 The Natural Products Atlas Classification

20.13 Consumer Product Information Database Classification

20.14 EPA TSCA and CDR Classification

20.15 LOTUS Tree

20.16 EPA Substance Registry Services Tree

20.17 MolGenie Organic Chemistry Ontology

21 Information Sources

  1. Australian Industrial Chemicals Introduction Scheme (AICIS)
    Cyclohexene, 1-methyl-4-(1-methylethenyl)-
    https://services.industrialchemicals.gov.au/search-assessments/
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  13. International Fragrance Association (IFRA)
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  16. Occupational Safety and Health Administration (OSHA)
    LICENSE
    Materials created by the federal government are generally part of the public domain and may be used, reproduced and distributed without permission. Therefore, content on this website which is in the public domain may be used without the prior permission of the U.S. Department of Labor (DOL). Warning: Some content - including both images and text - may be the copyrighted property of others and used by the DOL under a license.
    https://www.dol.gov/general/aboutdol/copyright
  17. California Safe Cosmetics Program (CSCP) Product Database
    Limonene (1-methyl-4-prop-1-en-2-yl-cyclohexene; dl-limonene (racemic); Dipentene; (R)-p-mentha-1,8-diene; (d-limonene); (S)-p-mentha-1,8-diene; (l-limonene))
    https://cscpsearch.cdph.ca.gov/search/detailresult/2507
  18. Consumer Product Information Database (CPID)
    LICENSE
    Copyright (c) 2024 DeLima Associates. All rights reserved. Unless otherwise indicated, all materials from CPID are copyrighted by DeLima Associates. No part of these materials, either text or image may be used for any purpose other than for personal use. Therefore, reproduction, modification, storage in a retrieval system or retransmission, in any form or by any means, electronic, mechanical or otherwise, for reasons other than personal use, is strictly prohibited without prior written permission.
    https://www.whatsinproducts.com/contents/view/1/6
    Consumer Products Category Classification
    https://www.whatsinproducts.com/
  19. NORMAN Suspect List Exchange
    LICENSE
    Data: CC-BY 4.0; Code (hosted by ECI, LCSB): Artistic-2.0
    https://creativecommons.org/licenses/by/4.0/
    Limonene
    NORMAN Suspect List Exchange Classification
    https://www.norman-network.com/nds/SLE/
  20. Emergency Response Guidebook (ERG)
  21. Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
    LICENSE
    Copyright (c) 2022 Haz-Map(R). All rights reserved. Unless otherwise indicated, all materials from Haz-Map are copyrighted by Haz-Map(R). No part of these materials, either text or image may be used for any purpose other than for personal use. Therefore, reproduction, modification, storage in a retrieval system or retransmission, in any form or by any means, electronic, mechanical or otherwise, for reasons other than personal use, is strictly prohibited without prior written permission.
    https://haz-map.com/About
  22. ChEBI
  23. LOTUS - the natural products occurrence database
    LICENSE
    The code for LOTUS is released under the GNU General Public License v3.0.
    https://lotus.nprod.net/
  24. NCI Thesaurus (NCIt)
    LICENSE
    Unless otherwise indicated, all text within NCI products is free of copyright and may be reused without our permission. Credit the National Cancer Institute as the source.
    https://www.cancer.gov/policies/copyright-reuse
  25. Yeast Metabolome Database (YMDB)
    LICENSE
    YMDB is offered to the public as a freely available resource.
    http://www.ymdb.ca/downloads
  26. ChEMBL
    LICENSE
    Access to the web interface of ChEMBL is made under the EBI's Terms of Use (http://www.ebi.ac.uk/Information/termsofuse.html). The ChEMBL data is made available on a Creative Commons Attribution-Share Alike 3.0 Unported License (http://creativecommons.org/licenses/by-sa/3.0/).
    http://www.ebi.ac.uk/Information/termsofuse.html
  27. ClinicalTrials.gov
    LICENSE
    The ClinicalTrials.gov data carry an international copyright outside the United States and its Territories or Possessions. Some ClinicalTrials.gov data may be subject to the copyright of third parties; you should consult these entities for any additional terms of use.
    https://clinicaltrials.gov/ct2/about-site/terms-conditions#Use
  28. DailyMed
  29. EPA Chemical and Products Database (CPDat)
  30. EPA Pesticide Ecotoxicity Database
  31. EU Food Improvement Agents
  32. Hazardous Chemical Information System (HCIS), Safe Work Australia
  33. NITE-CMC
    dipentene; limonene - FY2008 (New/original classication)
    https://www.chem-info.nite.go.jp/chem/english/ghs/08-mhlw-0048e.html
  34. Regulation (EC) No 1272/2008 of the European Parliament and of the Council
    LICENSE
    The copyright for the editorial content of this source, the summaries of EU legislation and the consolidated texts, which is owned by the EU, is licensed under the Creative Commons Attribution 4.0 International licence.
    https://eur-lex.europa.eu/content/legal-notice/legal-notice.html
    (±)-1-methyl-4-(1-methylvinyl)cyclohexene
    https://eur-lex.europa.eu/eli/reg/2008/1272/oj
  35. FDA Substances Added to Food
    LICENSE
    Unless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.
    https://www.fda.gov/about-fda/about-website/website-policies#linking
  36. FooDB
    LICENSE
    FooDB is offered to the public as a freely available resource. Use and re-distribution of the data, in whole or in part, for commercial purposes requires explicit permission of the authors and explicit acknowledgment of the source material (FooDB) and the original publication.
    https://foodb.ca/about
  37. MassBank Europe
  38. MassBank of North America (MoNA)
    LICENSE
    The content of the MoNA database is licensed under CC BY 4.0.
    https://mona.fiehnlab.ucdavis.edu/documentation/license
  39. NIST Mass Spectrometry Data Center
    LICENSE
    Data covered by the Standard Reference Data Act of 1968 as amended.
    https://www.nist.gov/srd/public-law
  40. SpectraBase
    4-ISOPROPENYL-1-METHYLCYCLOHEXENE
    https://spectrabase.com/spectrum/1LVF1pXeDYa
    CYCLOHEXENE, 4-ISOPROPENYL-1- METHYL-,
    https://spectrabase.com/spectrum/CV0EMjyNFP2
    4-Isopropenyl-1-methyl-1-cyclohexene
    https://spectrabase.com/spectrum/CJkcFiTUD3Q
  41. Japan Chemical Substance Dictionary (Nikkaji)
  42. KEGG
    LICENSE
    Academic users may freely use the KEGG website. Non-academic use of KEGG generally requires a commercial license
    https://www.kegg.jp/kegg/legal.html
  43. Lab and Research Safety, University of Minnesota
    Limonene
  44. Natural Product Activity and Species Source (NPASS)
  45. Metabolomics Workbench
  46. National Drug Code (NDC) Directory
    LICENSE
    Unless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.
    https://www.fda.gov/about-fda/about-website/website-policies#linking
  47. Nature Chemistry
  48. NIOSH Manual of Analytical Methods
    LICENSE
    The information provided using CDC Web site is only intended to be general summary information to the public. It is not intended to take the place of either the written law or regulations.
    https://www.cdc.gov/Other/disclaimer.html
  49. NLM RxNorm Terminology
    LICENSE
    The RxNorm Terminology is created by the National Library of Medicine (NLM) and is in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from NLM. Credit to the U.S. National Library of Medicine as the source is appreciated but not required. The full RxNorm dataset requires a free license.
    https://www.nlm.nih.gov/research/umls/rxnorm/docs/termsofservice.html
  50. Rhea - Annotated Reactions Database
    LICENSE
    Rhea has chosen to apply the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/). This means that you are free to copy, distribute, display and make commercial use of the database in all legislations, provided you credit (cite) Rhea.
    https://www.rhea-db.org/help/license-disclaimer
  51. Springer Nature
  52. Thieme Chemistry
    LICENSE
    The Thieme Chemistry contribution within PubChem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.
    https://creativecommons.org/licenses/by-nc-nd/4.0/
  53. Wikidata
  54. Wikipedia
  55. Wiley
  56. Medical Subject Headings (MeSH)
    LICENSE
    Works produced by the U.S. government are not subject to copyright protection in the United States. Any such works found on National Library of Medicine (NLM) Web sites may be freely used or reproduced without permission in the U.S.
    https://www.nlm.nih.gov/copyright.html
  57. PubChem
  58. GHS Classification (UNECE)
  59. The Natural Products Atlas
    LICENSE
    The Natural Products Atlas is licensed under a Creative Commons Attribution 4.0 International License.
    https://www.npatlas.org/terms
    The Natural Products Atlas Classification
    https://www.npatlas.org/
  60. EPA Substance Registry Services
  61. MolGenie
    MolGenie Organic Chemistry Ontology
    https://github.com/MolGenie/ontology/
  62. PATENTSCOPE (WIPO)
CONTENTS