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2-Methylpyridine

PubChem CID
7975
Structure
2-Methylpyridine_small.png
2-Methylpyridine_3D_Structure.png
2-Methylpyridine__Crystal_Structure.png
Molecular Formula
Synonyms
  • 2-METHYLPYRIDINE
  • 2-Picoline
  • 109-06-8
  • o-Picoline
  • alpha-Picoline
Molecular Weight
93.13 g/mol
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Dates
  • Create:
    2004-09-16
  • Modify:
    2024-12-14
Description
2-methylpyridine is a colorless liquid with a strong, unpleasant odor. Floats on water. Poisonous vapor is produced. (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.
Picolines is a clear colorless liquids with a strong unpleasant odor. Flash point 79 - 97 °F. Less dense than water. Vapors heavier than air. Toxic oxides of nitrogen produced during the combustion of. Used as a solvent and to make other chemicals.
2-methylpyridine is a methylpyridine carrying a methyl substituent at position 2.

1 Structures

1.1 2D Structure

Chemical Structure Depiction
2-Methylpyridine.png

1.2 3D Conformer

1.3 Crystal Structures

1 of 3
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CCDC Number
Crystal Structure Data
Crystal Structure Depiction
Crystal Structure Depiction

2 Names and Identifiers

2.1 Computed Descriptors

2.1.1 IUPAC Name

2-methylpyridine
Computed by Lexichem TK 2.7.0 (PubChem release 2021.10.14)

2.1.2 InChI

InChI=1S/C6H7N/c1-6-4-2-3-5-7-6/h2-5H,1H3
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.3 InChIKey

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

2.1.4 SMILES

CC1=CC=CC=N1
Computed by OEChem 2.3.0 (PubChem release 2021.10.14)

2.2 Molecular Formula

C6H7N
Computed by PubChem 2.2 (PubChem release 2021.10.14)

C6H7N

C5H4N(CH3)

2.3 Other Identifiers

2.3.1 CAS

109-06-8
1333-41-1

2.3.2 Deprecated CAS

45505-34-8, 82005-07-0

2.3.3 European Community (EC) Number

2.3.4 UNII

2.3.5 UN Number

2.3.6 ChEBI ID

2.3.7 ChEMBL ID

2.3.8 DSSTox Substance ID

2.3.9 HMDB ID

2.3.10 ICSC Number

2.3.11 KEGG ID

2.3.12 Metabolomics Workbench ID

2.3.13 Nikkaji Number

2.3.14 NSC Number

2.3.15 Wikidata

2.3.16 Wikipedia

2.4 Synonyms

2.4.1 MeSH Entry Terms

  • 2-methylpyridine
  • 2-picoline
  • 2-picolinium bromide

2.4.2 Depositor-Supplied Synonyms

3 Chemical and Physical Properties

3.1 Computed Properties

Property Name
Molecular Weight
Property Value
93.13 g/mol
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
XLogP3
Property Value
1.1
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
1
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Rotatable Bond Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Exact Mass
Property Value
93.057849228 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Monoisotopic Mass
Property Value
93.057849228 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Topological Polar Surface Area
Property Value
12.9Ų
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Heavy Atom Count
Property Value
7
Reference
Computed by PubChem
Property Name
Formal Charge
Property Value
0
Reference
Computed by PubChem
Property Name
Complexity
Property Value
52.1
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
0
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

2-methylpyridine is a colorless liquid with a strong, unpleasant odor. Floats on water. Poisonous vapor is produced. (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.
Picolines is a clear colorless liquids with a strong unpleasant odor. Flash point 79 - 97 °F. Less dense than water. Vapors heavier than air. Toxic oxides of nitrogen produced during the combustion of. Used as a solvent and to make other chemicals.
Liquid
Colorless liquid with a strong, unpleasant odor; [HSDB]
Colorless liquid with a strong unpleasant odor; [Hawley] Colorless or yellow tinted clear liquid; [MSDSonline]
COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

3.2.2 Color / Form

Colorless liquid
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
Colorless liquid /individual isomers/
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 992

3.2.3 Odor

Strong unpleasant odor
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
Strong, characteristic, sometimes unpleasant, obnoxious odor /individual isomers/
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374

3.2.4 Boiling Point

262 to 264 °F at 760 mmHg (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
293 °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.
129.4 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
129.4 - 145.3 °C /individual isomers/
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
128-129 °C

3.2.5 Melting Point

-94 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
36.3 °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.
-66.65 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
-66.65 to 3.68 °C /individual isomers/
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
-70 °C

3.2.6 Flash Point

97 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
134 °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.
26 °C
102 °F (39 °C)(Open cup)
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-99
26 °C c.c.

3.2.7 Solubility

greater than or equal to 100 mg/mL at 68 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
Miscible in water at 20 °C
Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
Very sol in acetone
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
Miscible with alcohol, ether
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
Miscible in water at 20 °C /individual isomers/
Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005
Solubility in water: miscible

3.2.8 Density

0.944 at 68 °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.
0.957 (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.
0.9443 at 20 °C/4 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
0.9443 to 0.9566 g/cu cm at 20 °C /individual isomers/
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
Relative density (water = 1): 0.95

3.2.9 Vapor Density

3.21 (NTP, 1992) - Heavier than air; will sink (Relative to Air)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
3.2 (Air= 1)
International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983., p. 1811
Relative vapor density (air = 1): 3.2

3.2.10 Vapor Pressure

8 mmHg at 68 °F ; 40 mmHg at 124.2 °F; 100 mmHg at 160.5 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
11.2 [mmHg]
Vapor pressure = 11.4 hPa at 20.3 °C (8.55 mm Hg)
European Commission; IUCLID Dataset, 2-Methylpyridine (CAS No. 109-06-8), Feb 8, 2000; Available from, as of Sept 19, 2014: https://esis.jrc.ec.europa.eu/doc/IUCLID/datasheet/109068.pdf
11.2 mm Hg at 25 °C
Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
5.77 to 11.2 mm Hg at 25 °C /individual isomers/
Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
Vapor pressure, kPa at 20 °C: 1.2

3.2.11 LogP

log Kow = 1.11
Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 20
log Kow = 1.11 - 1.22 /individual isomers/
Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 20
1.1

3.2.12 Henry's Law Constant

Henry's Law constant = 9.96X10-6 atm-cu m/mol @ 25 °C
Andon RJL; J Amer Chem Soc 76:3188-96 (1954)
Henry's Law constant = 6.00X10-6 to 9.96X10-12 atm-cu m/mol at 25 °C /individual isomers/
Andon RJL; J Amer Chem Soc 76: 3188-96 (1954)

3.2.13 Stability / Shelf Life

2-Methylpyridine is highly stable in aqueous solns ... .
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 220

3.2.14 Autoignition Temperature

1000 °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.
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.
1000 °F (538 °C)
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-99
538 °C

3.2.15 Decomposition

When heated to decomp, emits toxic fumes of /nitrogen oxides. /
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520

3.2.16 pH

/SRP/: Weak base

3.2.17 Ionization Efficiency

Ionization mode
Positive
logIE
3.37
pH
2.7
Instrument
Agilent XCT
Ion source
Electrospray ionization
Additive
formic acid (5.3nM)
Organic modifier
MeCN (80%)
Reference

3.2.18 Odor Threshold

Odor Threshold Low: 0.01 [mmHg]

Odor Threshold High: 0.45 [mmHg]

[ICSC] Odor threshold low = 0.05 mg/m3

...the odor treshold of this substance is relative low 0.05 - 0.1 ppm and is therefore a warning signal for exposure.
European Commission/European Chemical Substances Information System (ESIS); IUCLID Dataset, 2-Methylpyridine (CAS 109-06-8) p. 36 (2000). Available from, as of October 20, 2014: https://esis.jrc.ec.europa.eu//
0.05 mg/cu m (odor low); 0.17 mg/cu m (odor high).
Ruth JH; Am Ind Hyg Assoc J 47: A-142-51 (1986)

3.2.19 Refractive Index

Index of refraction: 1.4957 at 20 °C/D
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394
Index of refraction: 1.4957 to 1.5040 at 20 °C /individual isomers/
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-394

3.2.20 Dissociation Constants

pKa = 5.96 at 20 °C
Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.

3.2.21 Kovats Retention Index

Standard non-polar
792, 790, 787, 802, 803, 805, 787, 814, 804, 799, 800, 800, 804, 814, 799, 799, 800, 801, 802, 820, 792, 792, 799, 800, 825, 797.1, 799, 792.9, 797, 799, 799, 770, 772, 795, 798, 799
Semi-standard non-polar
821, 818, 824, 824, 821, 811, 814, 807, 802.3, 802.2, 803, 816, 816, 816, 816, 817, 818, 818, 818, 818, 818, 819, 819, 819, 819, 816, 816, 818, 818, 819, 819, 837, 786.6, 805.4, 811, 808, 815, 825, 826, 820, 778.3, 815, 816, 816, 121.17, 130.12, 125.11
Standard polar
1211, 1213, 1213, 1213, 1214, 1206, 1214, 1211, 1216, 1227, 1200, 1222, 1223, 1226, 1226, 1242, 1242, 1242, 1215.677, 1190, 1234, 1212, 1225, 1265, 1218, 1222, 1224, 1262, 1266, 1205, 1240, 1229, 1239, 1243, 1240, 1240, 1234, 1216, 1240, 1234, 1241, 1239, 1239, 1239, 1219, 1214, 1219, 1226.9, 1182, 1216, 1210, 1209, 1209, 1209, 1210, 1210, 1211, 1212, 1180, 1180, 1220, 1210

3.2.22 Other Experimental Properties

/SRP/: Forms salts with acids.
Freezing point = -66.7 °C
Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
Hydroxyl radical reaction rate constant = 2.79X10-12 cu cm/molecule-sec at 25 °C
NIST; NIST Chemistry WebBook. 2-Methylpyridine (109-06-8). NIST Standard Reference Database No. 69, June 2005 Release. Washington, DC: US Sec Commerce. Available from, as of Sept 19, 2014: https://webbook.nist.gov/chemistry
Picoline exists in three isomeric forms /alpha-picoline, beta-picoline, & gamma-picoline/
International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983., p. 1811
Hydroxyl radical reaction rate constant = 2.30X10-12 to 2.69X10-12 cu cm/molecule-sec at 25 °C /individual isomers/
NIST; Chemistry WebBook. National Institute of Standards and Technology Standard Reference Database Number 69 - March 2003 Release, Available from the query page at https://webbook.nist.gov/chemistry

3.3 SpringerMaterials Properties

3.4 Chemical Classes

Nitrogen Compounds -> Pyridines

3.4.1 Drugs

Pharmaceuticals -> Listed in ZINC15
S55 | ZINC15PHARMA | Pharmaceuticals from ZINC15 | DOI:10.5281/zenodo.3247749

4 Spectral Information

4.1 1D NMR Spectra

1 of 2
1D NMR Spectra
NMR: 566 (Sadtler Research Laboratories Spectral Collection)
2 of 2
1D NMR Spectra

4.1.1 1H NMR Spectra

1 of 3
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Spectra ID
Instrument Type
JEOL
Frequency
90 MHz
Solvent
CDCl3
Shifts [ppm]:Intensity
7.17:129.00, 7.08:141.00, 7.05:68.00, 7.63:42.00, 7.00:46.00, 8.50:69.00, 7.65:41.00, 7.13:83.00, 7.00:50.00, 7.46:85.00, 2.55:1000.00, 6.99:46.00, 8.46:72.00, 7.54:95.00, 7.14:85.00, 8.45:73.00, 7.57:79.00, 7.48:88.00
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Instrument Name
BRUKER AC-300
Source of Sample
Fluka AG, Buchs, Switzerland
Copyright
Copyright © 1991-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.1.2 13C NMR Spectra

1 of 3
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Spectra ID
Instrument Type
Varian
Frequency
25.16 MHz
Solvent
CDCl3
Shifts [ppm]:Intensity
120.72:854.00, 24.30:529.00, 158.29:272.00, 136.28:1000.00, 149.00:888.00, 123.27:922.00
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Source of Sample
Fluka AG, Buchs, Switzerland
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.1.3 15N NMR Spectra

1 of 2
Copyright
Copyright © 2016-2024 W. Robien, Inst. of Org. Chem., Univ. of Vienna. All Rights Reserved.
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2 of 2
Copyright
Copyright © 2016-2024 W. Robien, Inst. of Org. Chem., Univ. of Vienna. All Rights Reserved.
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4.2 Mass Spectrometry

4.2.1 GC-MS

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

93.0 99.99

66.0 39.32

92.0 20.36

65.0 14.50

78.0 14.42

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Notes
instrument=HITACHI M-80
2 of 15
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Spectra ID
Instrument Type
EI-B
Ionization Mode
positive
Top 5 Peaks

93.0 99.99

66.0 39.50

39.0 33

92.0 19.40

78.0 17.80

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Notes
instrument=Unknown

4.2.2 Other MS

1 of 4
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Other MS
MASS: 193 (Atlas of Mass Spectral Data, John Wiley & Sons, New York)
2 of 4
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Authors
MASS SPECTROSCOPY SOC. OF JAPAN (MSSJ)
Instrument
Unknown
Instrument Type
EI-B
MS Level
MS
Ionization Mode
POSITIVE
Top 5 Peaks

93 999

66 395

39 330

92 194

78 178

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License
CC BY-NC-SA

4.3 UV Spectra

UV: 6 (Sadtler Research Laboratories Spectral Collection)
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. V5: 4724

4.4 IR Spectra

IR Spectra
IR: 7 (Sadtler Research Laboratories IR Grating Collection)

4.4.1 FTIR Spectra

1 of 2
Technique
NEAT
Source of Sample
Environmental Protection Agency
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
Cell
Copyright
Copyright © 1989, 1990-2024 Wiley-VCH Verlag GmbH & Co. KGaA. All Rights Reserved.
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4.4.2 ATR-IR Spectra

1 of 2
Technique
ATR-Neat
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Source of Sample
Aldrich
Catalog Number
109835
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 Near IR Spectra

1 of 2
Instrument Name
INSTRUMENT PARAMETERS=INST=BRUKER,RSN=6405,REO=2,CNM=HEI,ZFF=2
Technique
NIR Spectrometer= BRUKER IFS 88
Source of Spectrum
Prof. Buback, University of Goettingen, Germany
Copyright
Copyright © 1989, 1990-2024 Wiley-VCH Verlag GmbH & Co. KGaA. All Rights Reserved.
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2 of 2
Instrument Name
INSTRUMENT PARAMETERS=INST=BRUKER,RSN=6405,REO=2,CNM=HEI,ZFF=2
Technique
NIR Spectrometer= BRUKER IFS 88
Source of Spectrum
Prof. Buback, University of Goettingen, Germany
Copyright
Copyright © 1989, 1990-2024 Wiley-VCH Verlag GmbH & Co. KGaA. All Rights Reserved.
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4.4.4 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

Catalog Number
109835
Copyright
Copyright © 2017-2024 Sigma-Aldrich Co. LLC. - Database Compilation Copyright © 2017-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.6 Other Spectra

Intense mass spectral peaks: 93 m/z (100%), 66 m/z (41%), 92 m/z (19%), 51 m/z (19%)
Hites, R.A. Handbook of Mass Spectra of Environmental Contaminants. Boca Raton, FL: CRC Press Inc., 1985., p. 180

6 Chemical Vendors

7 Food Additives and Ingredients

7.1 Food Additive Classes

Flavoring Agents

7.2 Associated Foods

8 Pharmacology and Biochemistry

8.1 Absorption, Distribution and Excretion

Alpha-picoline was rapidly absorbed by blood & penetrated into liver, heart, spleen, lungs, & muscles during 1St 10-20 min following oral admin of 0.5 g/kg to rats. It was excreted in urine during 1St 48 hr.
KUPOR VG; VOP PATOKHIMII BIOKHIM BELKOV DRUGIKH BIOL AKTIV SOEDIN: 51-2 (1972)
Addition of a methyl group onto the pyridine molecule increases the rate of absorption of the resultant picolines into the liver, kidney, & brain of rats. After ip injection of the picolines, pharmacokinetic parameters were greatly dependent upon the position of the methyl group. For example, the residence time for beta-picoline in liver, brain, & kidney was > that of alpha- or gamma-picoline. Elimination of all four pyridines was biphasic in nature, the first phase being more prolonged for pyridine & beta-picoline than for alpha- or gamma-picoline.
Zharikov GP et al; Deposited Doc (VINITI 1299-83): 11 pages (1983)
The substance is rapidly absorbed by the blood and penetrated into liver, heart, spleen, lungs, brain and muscles during the first 10 - 20 minutes after oral administration of 500 mg/kg to rats. It is excreted in urine mainly during the first 48 hrs after administration. Prevalent accumulation in the liver within 1 hr. Within 2 days however, the levels of the substance in the organs was decreased to traces.
European Commission/European Chemical Substances Information System (ESIS); IUCLID Dataset, 2-Methylpyridine (CAS 109-06-8) p. 36 (2000). Available from, as of October 20, 2014: https://esis.jrc.ec.europa.eu//
Addition of a methyl group to pyridine greatly increased the rate of uptake into the liver, kidney and brain of rats. The position of the methyl group drastically influenced the pharmacokinetics of the methylpyridines...
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 227
Methylpyridines are absorbed by inhalation, ingestion or percutaneous absorption.
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 220
Pyridine and its alkyl derivatives are absorbed from the gastrointestinal tract, intraperitoneal cavity and lungs, with the peritoneal route being slightlymore rapid and complete than gastrointestinal absorption. The methylpyridines also are rapidly absorbed through the skin.
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 234

8.2 Metabolism / Metabolites

... In rabbits and dogs /2-methylpyridine/ is oxidized to alpha-picolinic acid which is excreted in the urine. alpha-Picolinuric acid is also excreted by frogs administered alpha-picoline, but only in amounts less than 1% of the dose. In hens it is excreted partly as alpha-pyridinornithuric acid.
ITC/USEPA; Information Review #425 (Draft) Methylpyridines p.34 (1984)
/It was observed that/ 96% of a 100 mg/kg oral dose of 2-methylpyridine administered to rats was excreted in the urine as picolinuric acid.
ITC/USEPA; Information Review #425 (Draft) Methylpyridines p.34 (1984)
There also is evidence that 2-methylpyridine forms an N-methylated derivative in dogs.
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 220
Although the exact mechanism has not been determined, it appears that all methylpyridines are oxidized to their respective aromatic acids.
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 234

9 Use and Manufacturing

9.1 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 as a solvent and chemical intermediate for dyes and resins; [HSDB]
Sources/Uses
Used as an intermediate (dyes, resins, agrochemicals, and pharmaceuticals), solvent, and laboratory reagent; [HSDB] Found naturally in coal tar; Used as a solvent and to make dyes and resins; [MSDSonline] Picolines are constituents in cigarette smoke, bone oil, coal tar, and coke oven emissions. [AIHA]
AIHA - Workplace Environmental Exposure Level Guides, Complete Set and Update Set. Fairfax, VA: AIHA, 2008.
Intermediate in dye and resins industries; solvent.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
Organic intermediate for ... rubber chemicals, solvent, ... laboratory reagent.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 992
Used as a chemical intermediate for the synthesis of: 2-amino-6-methylpyridine; betahistine; bis-acodyl; clopyralid; 2-methylpiperidine; perhexiline; ... picolinic acid; /and/ thioridazine.
Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994., p. 697
The primary use of 2-methylpyridine is as a precursor of 2-vinylpyridine. It is also used in a variety of agrochemicals and pharmaceuticals, e.g., nitrapyrin to prevent loss of ammonia from fertilizers; picloram, a herbicide; and amprolium, a coccidiostat.
Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
Intermediate in dye and resins industry, solvent /2-, 3- and 4-Methylpyridine/
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374

9.1.1 Use Classification

Food additives -> Flavoring Agents
Hazard Classes and Categories -> Flammable - 2nd degree
Hazard Classes and Categories -> Flammable - 3rd degree

9.1.2 Industry Uses

Intermediates

9.1.3 Consumer Uses

Intermediates

9.2 Methods of Manufacturing

... The reaction of acrylonitrile and acetone, catalyzed by a primary aliphatic amine such as isopropylamine and a weak acid such as benzoic acid, occurs in the liquid phase at 180 °C and 2.2 MPa to give 5-oxohexanenitrile, with 91% selectivity. The acrylonitrile conversion is 86%. Then cyclization and dehydration of the initial product are carried out in the gas phase in the presence of hydrogen over a palladium, nickel, or cobalt- containing catalyst at ca. 240 °C to give 2-methylpyridine in 84% yield.
Shimizu S et al; Pyridinie and Pyridine Derivatives. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2014). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000
... Acetonitrile and acetylene react in the presence of cobaltocene as catalyst to give 2-methylpyridine in 76% yield.
Shimizu S et al; Pyridinie and Pyridine Derivatives. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2014). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000
Synthesis (40-50% yield) from cyclohexylamine with excess ammonia and zinc chloride at 350 °C.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
Prepared from ethylene-mercuric acetate adduct and ammonia water (70% yield).
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
For more Methods of Manufacturing (Complete) data for 2-METHYLPYRIDINE (8 total), please visit the HSDB record page.
DISTILLATION OF THE CHEMICAL OIL, FROM THE COKING OF COAL, BETWEEN THE TEMPERATURES OF 130 AND 196 °C PER ATM
CONSIDINE. CHEMICAL AND PROCESS TECHNOL ENCYC 1974 p.943

9.3 Impurities

PYRIDINE IS THE MAJOR IMPURITY TO THE DISTILLATE
CONSIDINE. CHEMICAL AND PROCESS TECHNOL ENCYC 1974 p.943

9.4 U.S. Production

Aggregated Product Volume

2019: 1,000,000 lb - <20,000,000 lb

2018: 1,000,000 lb - <20,000,000 lb

2017: 1,000,000 lb - <20,000,000 lb

2016: 20,000,000 lb - <100,000,000 lb

(1972) PROBABLY GREATER THAN 1.82X10+6 GRAMS
SRI
(1975) 1.73X10+8 GRAMS
SRI
1.89X10+5 kg (1976)
Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed., Volumes 1-26. New York, NY: John Wiley and Sons, 1978-1984., p. V8 175
(1989) ca. 8000 t/a
Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA22 (1993) 407
For more U.S. Production (Complete) data for 2-METHYLPYRIDINE (7 total), please visit the HSDB record page.
Non-confidential 2012 Chemical Data Reporting (CDR) information on the production and use of chemicals manufactured or imported into the United States. Chemical: Benzonitrile. National Production Volume: Withheld.
USEPA/Pollution Prevention and Toxics; 2012 Chemical Data Reporting Database. Benzonitrile (100-47-0). Available from, as of October 22, 2014: https://java.epa.gov/oppt_chemical_search/

9.5 U.S. Imports

(1972) 1.09X10+9 GRAMS (ALL PICOLINES)
SRI
(1975) 1.78X10+9 GRAMS (ALL PICOLINES)
SRI

9.6 General Manufacturing Information

Industry Processing Sectors
  • Pharmaceutical and Medicine Manufacturing
  • Pesticide, Fertilizer, and Other Agricultural Chemical Manufacturing
EPA TSCA Commercial Activity Status
Pyridine, 2-methyl-: ACTIVE
EPA TSCA Commercial Activity Status
Pyridine, methyl-: ACTIVE
Pyridine bases are a constituent of tars. They were isolated from coal tar or coal gas before synthetic manufacturing processes became established. The amounts contained in coal tar and coal gas are small, and the pyridine bases isolated from them are a mixture of many components. Thus, with a few exceptions, isolation of pure pyridine bases was expensive. Today, almost all pyridine bases are produced by synthesis. /Pridine bases/
Shimizu S et al; Pyridinie and Pyridine Derivatives. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2014). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000
Shimizu S et al; Pyridinie and Pyridine Derivatives. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2014). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000
...vapor-phase synthesis of pyridines from ammonia and aldehydes or ketones produces pyridine or an alkylated pyridine as a primary product, as well as isomeric alkylpyridines and higher substituted alkylpyridines, along with their isomers. Furthermore, self-condensation of aldehydes and ketones can produce substituted benzenes. Condensation of ammonia with the aldehydes can produce certain alkyl or unsaturated nitrile side products. Lastly, self-condensation of the aldehydes and ketones, perhaps with reduction, can lead to alkanes and alkenes. /Alkylated pyridines/
Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. Volumes 1: New York, NY. John Wiley and Sons, 1991-Present., p. V20: 663 (1996)

10 Identification

10.1 Analytic Laboratory Methods

Method: EPA-RCA 8270D; Procedure: gas chromatography/mass spectrometry; Analyte: 2-methylpyridine; Matrix: solid waste matrices, soils, air sampling media and water; Detection Limit: not provided.
National Environmental Methods Index; Analytical, Test and Sampling Methods. 2-Methylpyridine (109-06-8). Available from, as of October 23, 2014: https://www.nemi.gov
Method: EPA-RCA 8260B; Procedure: gas chromatography/mass spectrometry; Analyte: 2-methylpyridine; Matrix: various; Detection Limit: not provided.
National Environmental Methods Index; Analytical, Test and Sampling Methods. 2-Methylpyridine (109-06-8). Available from, as of October 23, 2014: https://www.nemi.gov
Method: EPA-RCA 8015C; Procedure: gas chromatography with flame ionization detector; Analyte: 2-methylpyridine; Matrix: surface water, ground water, and solid matrices; Detection Limit: not provided.
National Environmental Methods Index; Analytical, Test and Sampling Methods. 2-Methylpyridine (109-06-8). Available from, as of October 23, 2014: https://www.nemi.gov
Method: EPA-RCA 5030C; Procedure: purge and trap; Analyte: 2-methylpyridine; Matrix: water; Detection Limit: not provided.
National Environmental Methods Index; Analytical, Test and Sampling Methods. 2-Methylpyridine (109-06-8). Available from, as of October 23, 2014: https://www.nemi.gov
For more Analytic Laboratory Methods (Complete) data for 2-METHYLPYRIDINE (9 total), please visit the HSDB record page.
NIOSH Method 1613. Analysis of air samples for pyridine using gas chromatography with FID detection. Working range of 1 to 14 ppm (3 to 45 mg/cu m) for a 100-L air sample /Pyridine/
U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. NIOSH Manual of Analytical Methods. 4th ed. Methods A-Z & Supplements. Washington, DC: U.S. Government Printing Office, Aug 1994.
Pyridine and its derivatives in water and sediment were determined by gas chromatography. Recovery was 95, 90, and 84% from purified water, river water, and sediment, respectively. The detection limit was 0.001 mg/l water and 0.01 mg/l sediment. /Pyridine and its derivatives/
Sasai H, Tsufioka T; Nagano-ken Eisei Kogai Kenkyusho Kenkyu Hokoku 3: 55-7 (1981)
OSW Method 8240B. Determination of Volatile Organics by Gas Chromatography/Mass Spectrometry (GC/MS). Gas chromatography with low resolution mass spectrometry. No detection limit reported. (2-, 3-, and 4-Methylpyridine/
USEPA; EMMI. EPA's Environmental Monitoring Methods Index. Version 1.1. PC# 4082. Rockville, MD: Government Institutes (1997)

11 Safety and Hazards

11.1 Hazards Identification

11.1.1 GHS Classification

1 of 5
View All
Pictogram(s)
Flammable
Corrosive
Acute Toxic
Irritant
Signal
Danger
GHS Hazard Statements

H226 (100%): Flammable liquid and vapor [Warning Flammable liquids]

H302 (100%): Harmful if swallowed [Warning Acute toxicity, oral]

H311 (47.1%): Toxic in contact with skin [Danger Acute toxicity, dermal]

H312 (52.9%): Harmful in contact with skin [Warning Acute toxicity, dermal]

H314 (36.1%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

H319 (91%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H331 (48.6%): Toxic if inhaled [Danger Acute toxicity, inhalation]

H332 (54.6%): Harmful if inhaled [Warning Acute toxicity, inhalation]

H335 (98.3%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

Precautionary Statement Codes

P210, P233, P240, P241, P242, P243, P260, P261, P262, P264, P264+P265, P270, P271, P280, P301+P317, P301+P330+P331, P302+P352, P302+P361+P354, P303+P361+P353, P304+P340, P305+P351+P338, P305+P354+P338, P316, P317, P319, P321, P330, P337+P317, P361+P364, P362+P364, P363, P370+P378, P403+P233, 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 346 reports by companies from 19 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

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.

11.1.2 Hazard Classes and Categories

Flam. Liq. 3 (100%)

Acute Tox. 4 (100%)

Acute Tox. 3 (47.1%)

Acute Tox. 4 (52.9%)

Skin Corr. 1C (36.1%)

Eye Irrit. 2 (91%)

Acute Tox. 3 (48.6%)

Acute Tox. 4 (54.6%)

STOT SE 3 (98.3%)

Flammable liquid - category 3

Acute toxicity - category 4

Acute toxicity - category 4

Acute toxicity - category 4

Specific target organ toxicity (single exposure) - category 3

Eye irritation - category 2

11.1.3 NFPA Hazard Classification

NFPA 704 Diamond
2-3-0
NFPA Health Rating
2 - Materials that, under emergency conditions, can cause temporary incapacitation or residual injury.
NFPA Fire Rating
3 - Liquids and solids that can be ignited under almost all ambient temperature conditions. Materials produce hazardous atmospheres with air under almost all ambient temperatures or, though unaffected by ambient temperatures, are readily ignited under almost all conditions.
NFPA Instability Rating
0 - Materials that in themselves are normally stable, even under fire conditions.

11.1.4 Health Hazards

INHALATION, INGESTION OR SKIN ABSORPTION: Narcosis, headache, nausea, giddiness, vomiting. EYES: Severe irritation. SKIN: Causes burns. INGESTION: Irritation and gastric upset. (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.
Harmful if swallowed, inhaled or absorbed through the skin. Causes severe irritation. High concentrations are extremely destructive to tissues of the mucous membranes and upper respiratory tract, eyes and skin. Symptoms of exposure may include burning sensation, coughing, wheezing, laryngitis, shortness of breath, headache, nausea, vomiting and gastrointestinal disturbances. (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.

11.1.5 Fire Hazards

Special Hazards of Combustion Products: When heated to decompo- sition, emits toxic fumes of cyanide.

Behavior in Fire: Heat may cause pressure buildup in closed containers. Use water to keep container cool. (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.
Special Hazards of Combustion Products: Emits toxic fumes under fire conditions. Forms explosive mixture in air. (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.
Flammable. Gives off irritating or toxic fumes (or gases) in a fire. Above 26 °C explosive vapour/air mixtures may be formed.

11.1.6 Hazards Summary

May cause first degree burns after short exposure and second degree burns after longer contact; Liver and kidney injury after chronic exposure have been reported. [CHRIS] See Pyridine.
A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; Inhalation of high concentrations can cause unconsciousness; The liquid defats the skin; [ICSC] An irritant; Harmful if swallowed, inhaled, or absorbed through skin; A strong respiratory tract irritant; May cause convulsions; Oral LD50 (rat) = 790 mg/kg; [MSDSonline] An irritant that can cause CNS depression; Liver changes occur in rats exposed to chronic high doses; [AIHA] See Pyridine.
AIHA - Workplace Environmental Exposure Level Guides, Complete Set and Update Set. Fairfax, VA: AIHA, 2008.

11.1.7 Fire Potential

Moderate fire risk
Sax, N.I. and R.J. Lewis, Sr. (eds.). Hawley's Condensed Chemical Dictionary. 11th ed. New York: Van Nostrand Reinhold Co., 1987., p. 917
Flammable liquid 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. 2520

11.1.8 Skin, Eye, and Respiratory Irritations

Irritating to respiratory tract.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 1374
A skin and severe eye irritant.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520

11.1.9 EPA Hazardous Waste Number

U191; A toxic waste when a discarded commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate.

11.2 Safety and Hazard Properties

11.2.1 Critical Temperature & Pressure

Critical temperature: 622 K; critical pressure: 4.62 MPa
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 6-69

11.2.2 Explosive Limits and Potential

Explosive limits , vol% in air: 1.4-8.6

11.3 First Aid Measures

Inhalation First Aid
Fresh air, rest. Refer for medical attention.
Skin First Aid
Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention .
Eye First Aid
First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.
Ingestion First Aid
Rinse mouth. Do NOT induce vomiting. Refer for medical attention .

11.3.1 First Aid

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.

INHALATION: CALL FOR MEDICAL AID. Remove victim to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.

EYES: Flush with copious amounts of water for at least 15 minutes. Assure adequate flushing of the eyes by separating eyelids with fingers.

SKIN: Flush with copious amounts of water for at least 15 minutes while removing contaminated clothing and shoes. (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.

11.4 Fire Fighting

Fire Extinguishing Agents Not to Be Used: Water may be ineffective.

Fire Extinguishing Agents: Carbon dioxide, dry chemical or "alcohol" foam. (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.

Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:

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

SMALL FIRE: Dry chemical, CO2, water spray or alcohol-resistant foam. Do not use dry chemical extinguishers to control fires involving nitromethane (UN1261) or nitroethane (UN2842).

LARGE FIRE: Water spray, fog or 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. 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)

Use water spray, powder, alcohol-resistant foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water.

11.4.1 Fire Fighting Procedures

To fight fire, use carbon dioxide, dry chemical.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520
If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flood quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725
If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical, or cabon dioxide. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725

11.5 Accidental Release Measures

11.5.1 Isolation and Evacuation

Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:

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)

11.5.2 Spillage Disposal

Personal protection: chemical protection suit including self-contained breathing apparatus. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

11.5.3 Disposal Methods

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U191, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.
40 CFR 240-280, 300-306, 702-799 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of April 6, 2014: https://www.ecfr.gov
A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids. A potential candidate for liquid injection incineration at a temperature range of 650 to 1,600 °C and a residence time of 0.1 to 2 seconds. A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids.
USEPA; Engineering Handbook for Hazardous Waste Incineration p.3-15 (1981) EPA 68-03-3025
SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. 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 soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

11.5.4 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.
If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. Use water spray to disperse vapors and dilute standing pools of liquid. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725
Personnel protection: Avoid breathing vapors. Keep upwind. Avoid bodily contact with the material. Do not handle broken packages unless wearing appropriate personal protective equipment. ... Wash away any material which may have contacted the body with copious amounts of water or soap and water. ... If contact with material anticipated, wear appropriate chemical protective clothing. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725
SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit 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.
Personnel protection: Avoid breathing vapors. Keep upwind. Avoid bodily contact with the material. ... Do not handle broken packages unless wearing appropriate personal protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water. ... If contact with the material anticipated, wear appropriate chemical protective clothing. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725

11.6 Handling and Storage

11.6.1 Nonfire Spill Response

Neutralizing Agents for Acids and Caustics: Flush with water (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.

Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:

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)

11.6.2 Safe Storage

Fireproof. Separated from oxidants.

11.7 Exposure Control and Personal Protection

11.7.1 Other Standards Regulations and Guidelines

Workplace Environmental Exposure Level (WEEL): 8-hr Time-weighted Average (TWA) 2 ppm, skin; Short-term Exposure Limit (STEL) 5 ppm, 15 min, skin.
2013 Emergency Response Planning Guidelines (ERPG) & Workplace Exposure Level (WEEL). American Industrial Hygiene Association, Falls Church, VA 2013, p. 48

11.7.2 Inhalation Risk

A harmful contamination of the air can be reached rather quickly on evaporation of this substance at 20 °C.

11.7.3 Effects of Short Term Exposure

The substance is corrosive to the eyes and skin. The vapour is irritating to the respiratory tract. Exposure at high levels could cause unconsciousness.

11.7.4 Effects of Long Term Exposure

The substance defats the skin, which may cause dryness or cracking.

11.7.5 Personal Protective Equipment (PPE)

Wear goggles, rubber gloves, self-contained breathing apparatus and protective overclothing. (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 self-contained breathing apparatus, rubber boots, heavy rubber gloves, and protective clothing. (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.
Personnel protection: ... Wear appropriate chemical protective gloves, boots, and goggles. ... Wear positive pressire self-contained breathing apparatus when fighting fires involving this material. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725
Personnel protection: ... Wear appropriate chemical protective gloves, boots, and goggles. ... Wear positive pressure self-contained breathing apparatus when fighting fires involving this material. /Picolines/
Association of American Railroads; Bureau of Explosives. Emergency Handling of Hazardous Materials in Surface Transportation. Association of American Railroads, Pueblo, CO. 2005, p. 725

11.7.6 Preventions

Fire Prevention
NO open flames, NO sparks and NO smoking. Above 26 °C use a closed system, ventilation and explosion-proof electrical equipment.
Exposure Prevention
PREVENT GENERATION OF MISTS!
Inhalation Prevention
Use ventilation, local exhaust or breathing protection.
Skin Prevention
Protective gloves. Protective clothing.
Eye Prevention
Wear face shield or eye protection in combination with breathing protection.
Ingestion Prevention
Do not eat, drink, or smoke during work.

11.8 Stability and Reactivity

11.8.1 Air and Water Reactions

Highly flammable. Water soluble.
Highly flammable. Soluble in water.

11.8.2 Reactive Group

Amines, Phosphines, and Pyridines

11.8.3 Reactivity Alerts

Highly Flammable

11.8.4 Reactivity Profile

2-METHYLPYRIDINE is hygroscopic. This compound reacts with hydrogen peroxide, iron(II) sulfate, sulfuric acid, oxidizing agents, acids, and metals. (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
PICOLINES neutralizes acids in exothermic reactions to form salts plus water. It is incompatible with isocyanates, halogenated organics, peroxides, phenols, sulfuric acid, epoxides, anhydrides, acid halides and iron (II) sulfate. Gamma picoline may generate hydrogen, a flammable gas, in combination with strong reducing agents such as hydrides. Dangerous fire hazard when exposed to heat, flame or oxidizers. Severe explosion hazards in the form of vapor, when exposed to flame or spark. Reacts violently with chlorosulfonic acid; CrO3; maleic anhydride; HNO3; oleum; perchromates; B-propiolactone; AgClO4; H2SO4;formamide; SO3; I. Dangerous when heated to decomposition it emits highly toxic fumes of cyanides; can react vigorously with oxidizing materials.

11.8.5 Hazardous Reactivities and Incompatibilities

Mixtures with hydrogen peroxide + iron(II)sulfate + sulfuric acid may ignite & then explode.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520
Addition of 30% peroxide & sulfuric acid to 2-methylpyridine & iron(ii) sulfate caused sudden exotherm, followed by vapor phase explosion & ignition.
Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990, p. 1208

11.9 Transport Information

11.9.1 DOT Emergency Guidelines

/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ 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 "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. /Picolines/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Health: May cause toxic effects if inhaled or absorbed through skin. Inhalation or contact with material may irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. /Picolines/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Public Safety: CALL Emergency Response Telephone Number ... 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. /Picolines/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 129: FLAMMABLE LIQUIDS (POLAR/WATER-MISCIBLE/NOXIOUS)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. /Picolines/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
For more DOT Emergency Guidelines (Complete) data for 2-METHYLPYRIDINE (8 total), please visit the HSDB record page.
For more DOT Emergency Guidelines (Complete) data for METHYLPYRIDINES (8 total), please visit the HSDB record page.

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

UN 2313; Picolines
IMO 3; Picolines

11.9.3 Standard Transportation Number

49 131 74; Picoline (combustible liquid)
49 091 79; Picoline (flammable liquid)

11.9.4 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 October 21, 2014: https://www.ecfr.gov
49 CFR 171.2 (USDOT); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of October 21, 2014: 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. /Picolines/
International Air Transport Association. Dangerous Goods Regulations. 55th Edition. Montreal, Quebec Canada. 2014., p. 291
International Air Transport Association. Dangerous Goods Regulations. 55th Edition. Montreal, Quebec Canada. 2014., p. 291
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. /Picolines/
International Maritime Organization. IMDG Code. International Maritime Dangerous Goods Code Volume 2 2012, p. 113
International Maritime Organization. IMDG Code. International Maritime Dangerous Goods Code Volume 2 2012, p. 113

11.9.5 DOT Label

Flammable Liquid

11.9.6 Packaging and Labelling

Marine pollutant.

11.9.7 EC Classification

Symbol: Xn; R: 10-20/21/22-36/37; S: (2)-26-36

11.9.8 UN Classification

UN Hazard Class: 3; UN Pack Group: III

11.10 Regulatory Information

The Australian Inventory of Industrial Chemicals
Chemical: Pyridine, 2-methyl-
REACH Registered Substance
New Zealand EPA Inventory of Chemical Status
2-Methylpyridine: Does not have an individual approval but may be used under an appropriate group standard

11.10.1 CERCLA Reportable Quantities

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 5000 lb or 2270 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).
40 CFR 302.4 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of October 22, 2014: https://www.ecfr.gov

11.10.2 TSCA Requirements

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. 2-Methylpyridine is included on this list. Effective date: 09/10/84; Sunset date: 09/10/94.
40 CFR 716.120 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of October 22, 2014: https://www.ecfr.gov
Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Methylpyridine is included on this list. Effective date: 09/10/84; Sunset date: 12/29/88.
40 CFR 716.120 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of October 22, 2014: https://www.ecfr.gov

11.10.3 RCRA Requirements

U191; As stipulated in 40 CFR 261.33, when 2-methylpyridine, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).
40 CFR 261.33 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of October 22, 2014: https://www.ecfr.gov

11.11 Other Safety Information

11.11.1 Special Reports

ITC/USEPA; Information Review #425 (Draft) Methylpyridines (1984)

12 Toxicity

12.1 Toxicological Information

12.1.1 Toxicity Summary

IDENTIFICATION AND USE: 2-Methylpyridine is a colorless liquid with a strong unpleasant odor. It is used as organic intermediate for rubber and dye chemicals, solvent, laboratory reagent. 2-Methylpyridine is a chemical intermediate for the synthesis of: 2-amino-6-methylpyridine; betahistine; bis-acodyl; clopyralid; 2-methylpiperidine; perhexiline; picloram; picolinic acid; thioridazine; 2-vinylpyridine. HUMAN EXPOSURE AND TOXICITY: 2-Methylpyridine causes local irritation on contact with the skin, mucous membranes and cornea. Clinical signs of intoxication caused by the methylpyridines include weight loss, diarrhea, weakness, ataxia and unconsciousness as well as CNS depression, headache, giddiness and vomiting. Chronic exposure to methylpyridine results in anemia and ocular and facial paralysis in addition to the previously mentioned symptoms. It has been alleged that the workmen exposed to picoline vapors may develop diplopia as a result of disturbance of the eye muscles. ANIMAL STUDIES: Eye and skin irritant in rabbits. Chronic administration to rats decreased glycogen level and increased glucose and lactic acid levels in liver of rats throughout most of the study. In developmental study in rats structure and composition of the liver and the structure andgrowth pattern of the skin were disrupted in the offspring. 2-Methylpyridine affected electrophysiological parameters in rats. Ames test with and without metabolic activation in Salmonella typhimurium TA98, TA100, TA97, TA102, 10-5000 ug/plate was negative.
IDENTIFICATION AND USE: Methylpyridine is a colorless liquid. Methylpyridine is an intermediate in the dye and resins industry, solvent (2-, 3- and 4-Methylpyridine). HUMAN EXPOSURE AND TOXICITY: Clinical symptoms and signs of intoxication include gastrointestinal disturbance with diarrhea, abdominal pain, nausea, weakness, headache, insomnia, and nervousness. ANIMAL STUDIES: Methylpyridine is a skin irritant in rabbits. The changes observed in neurophysiological test in rats following methylpyridine administration were in many ways similar to those seen following administration of depressant compounds: increased latency of evoked potentials and increased latency to pentylenetetrazol seizures. In viro substituted pyridines influence the binding of nicotine to rat brain preparations.

12.1.2 Exposure Routes

The substance can be absorbed into the body by inhalation of its vapour, through the skin and by ingestion.

12.1.3 Symptoms

Inhalation Exposure
Cough. Dizziness. Drowsiness. Headache. Nausea. Sore throat. Unconsciousness. Weakness.
Skin Exposure
MAY BE ABSORBED! Dry skin. Redness. Burning sensation. Pain. Blisters. Further see Inhalation.
Eye Exposure
Redness. Pain. Blurred vision. Severe deep burns.
Ingestion Exposure
Abdominal pain. Burning sensation. Diarrhoea. Vomiting. Further see Inhalation.

12.1.4 Adverse Effects

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

Dermatotoxin - Skin burns.

Neurotoxin - Other CNS neurotoxin

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

Dermatotoxin - Skin burns.

12.1.5 Acute Effects

12.1.6 Toxicity Data

LCLo (rat) = 4,000 ppm/4h

12.1.7 Antidote and Emergency Treatment

/SRP:/ 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 as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on 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. /Aromatic hydrocarbons 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. 209
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. 209
/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal 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 ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat as 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. Administer activated charcoal ... . /Aromatic hydrocarbons 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. 209-10
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. 209-10
/SRP:/ Advanced treatment: Consider orortracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonistic such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W TKO /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) or lorazepam (Ativan) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Aromatic hydrocarbons 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. 210
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. 210

12.1.8 Human Toxicity Excerpts

/SIGNS AND SYMPTOMS/ 2-Methylpyridine causes local irritation on contact with the skin, mucous membranes & cornea. Clinical signs of intoxication caused by the methylpyridines include weight loss, diarrhea, weakness, ataxia and unconsciousness as well as /CNS depression/, headache, nausea, giddines and vomiting. Chronic exposure to methylpyridine results in anemia and ocular and facial paralysis in addition to the previously mentioned symptoms.
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 222
/CASE REPORTS/ ... It has been alleged that the workmen exposed to picoline vapors may develop diplopia as a result of disturbance of the eye muscles. /Picolines/
Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 737
/OTHER TOXICITY INFORMATION/ Reilly Industries Belgium In-House data: Workplace typical concentrations: 0.01 - 1.85 ppm (personal sampling workers 8hrs values). Fenceline typical concentrations: 0.4 - 4 ppb (fenceline monitoring data).
European Commission/European Chemical Substances Information System (ESIS); IUCLID Dataset, 2-Methylpyridine (CAS 109-06-8) p. 4 (2000). Available from, as of October 20, 2014: https://esis.jrc.ec.europa.eu//
/SIGNS AND SYMPTOMS/ The chemical and biological properties and health hazards of pyridine, 2-aminopyridine, 2-chloropyridine and a number of homologs of pyridine, picoline, vinyl-pyridine, piperidine, and quinoline are reviewed. Pyridine exists in liquid and vapor form. Concentrations of pyridine at 2,500 to 10,000 parts per million cause 100 percent mortality in rats. Most of the effects observed in humans are seen after repeated or intermittent exposure to the vapor. Clinical symptoms and signs of intoxication include gastrointestinal disturbance with diarrhea, abdominal pain, nausea, weakness, headache, insomnia, and nervousness; at low concentrations, pyridine causes varying degress of liver damage with central lobular fatty degeneration, congestion, and cellular infiltration. Pyridine causes irritation upon contact with skin, mucous membranes, and cornea. Safety measures include handling pyridine under well ventilated conditions. A charcoal gas mask cannister is effective in adsorbing pyridine. In the event of skin contact, the contaminated area should be washed with soap and water. Precautions recommended for pyridine are also applicable to its derivatives and homologs.
Gehring PJ; Encyclopaedia of Occupational Health and Safety 2: 1810-1812 (1983)
/SIGNS AND SYMPTOMS/ Clinical signs of intoxication caused by the methyl pyridines include weight loss, diarrhea, weakness, ataxia and unconsciousness as well as /CNS depression/ headache, nausea, giddiness and vomiting. Chronic exposure to methylpyridine results in anemia and ocular and facial paralysis in addition to the previously mentioned symptoms.
Snyder, R. (ed.). Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume II: Nitrogen and Phosphorus Solvents. Amsterdam-New York-Oxford: Elsevier, 1990., p. 222

12.1.9 Non-Human Toxicity Excerpts

/LABORATORY ANIMALS: Acute Exposure/ Tested by drop application on rabbit eyes, it has caused moderate injury, graded 8 on a scale of 1 to 10 after 24 hr ... /the most severe injuries have been rated 10/.
Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 737
/LABORATORY ANIMALS: Acute Exposure/ The eye and skin irritational properties of various picolines: 2-picoline, 3-picoline and 4-picoline, were evaluated and compared to those for pyridine ... /in/ male New Zealand albino rabbits ... . Following either 7 or 14 days the rabbits were killed and histological examinations were conducted on the eyes. Eye irritation, caused by these exposures, was characterized by ocular irritation indice (OII). Eye irritation assessments showed that irritation was maximal either 1 hr or 1 day after exposure. Based upon ocular irritation indice values, 2-picoline, 3-picoline and pyridine were classified as "irritating", while 4-picoline was classified a "severely irritating". ... Over longer periods of time, which included recovery, all four of these compounds were determined to be "severely irritating". Histological examination of the eyes showed similar effects for all four compounds considered. These effects included keratitis lesions in corneal epithelial tissue, fibrillary edematous lamallae dissociation, and cellular inflammatory infiltration. Skin irritation was characterized by the cutaneous primary irritation index (PII). 2-Picoline, 3-picoline, and pyridine had primary irritation index values of 5.8, 6.8, and 4.8 respectively, while 4-picoline showed such high percutaneous toxicity that a PII value could not be determined. Overall results on skin irritation suggested that 2-picoline and 3-picoline should be classified as "severely irritating" with pyridine being classified as "irritating". Histological exam of the skin provided evidence for necrosis, ulceration, and regeneration. ...
Dutertre-Catella H et al; Archives of Toxicology Suppl 13: 428-32 (1989)
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ Daily oral admin of 50 mg/kg for 4 MO decreased glycogen level & incr glucose & lactic acid levels in liver of rats throughout most of the study.
KUPOR VG, GRUZDEVA KN; NARUSHENIYA METAB, TR NAUCHN KONF MED INST ZEPADN SIB, 1ST: 261-5 (1974)
/LABORATORY ANIMALS: Developmental or Reproductive Toxicity/ /Rat oral administration daily throughout pregnancy 157 mg/kg/day/ Structure and composition of the liver and the structure andgrowth pattern of the skin were disrupted in the offspring.
European Commission/European Chemical Substances Information System (ESIS); IUCLID Dataset, 2-Methylpyridine (CAS 109-06-8) p. (2000). Available from, as of October 20, 2014: https://esis.jrc.ec.europa.eu//
For more Non-Human Toxicity Excerpts (Complete) data for 2-METHYLPYRIDINE (9 total), please visit the HSDB record page.
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ The eye and skin irritational properties of various picolines: 2-picoline, 3-picoline and 4-picoline, were evaluated and compared to those for pyridine ... /in/ male New Zealand albino rabbits ... . Following either 7 or 14 days the rabbits were killed and histological examinations were conducted on the eyes. Eye irritation, caused by these exposures, was characterized by ocular irritation indice (OII). Eye irritation assessments showed that irritation was maximal either 1 hour or 1 day after exposure. Based upon ocular irritation indice values, 2-picoline, 3-picoline and pyridine were classified as "irritating", while 4-picoline was classified a "severely irritating". ... Over longer periods of time, which included recovery, all four of these compounds were determined to be "severely irritating". Histological examination of the eyes showed similar effects for all four compounds considered. These effects included keratitis lesions in corneal epithelial tissue, fibrillary edematous lamallae dissociation, and cellular inflammatory infiltration. Skin irritation was characterized by the cutaneous primary irritation index (PII). 2-Picoline, 3-picoline, and pyridine had primary irritation index values of 5.8, 6.8, and 4.8 respectively, while 4-picoline showed such high percutaneous toxicity that a primary irritation index value could not be determined. Overall results on skin irritation suggested that 2-picoline and 3-picoline should be classified as "severely irritating" with pyridine being classified as "irritating". Histological exam of the skin provided evidence for necrosis, ulceration, and regeneration. ...
Dutertre-Catella H et al; Archives of Toxicology Suppl 13: 428-32 (1989)
/LABORATORY ANIMALS: Neurotoxicity/ A series of neurophysiological tests was performed on Long-Evans hooded rats treated with either 2-, 3-, or 4-methylpyridine at dosages of 100 mg/kg, approximately one-half the ip LD50. The tests contained measures of sensory function (paired pulse flash evoked potentials, pattern reversal evoked potentials, and brainstem auditory evoked responses) and cerebral excitability (pentylenetetrazol seizures and hippocampal afterdischarges). In general, rats treated with 2- and 3-methylpyridine were more affected than those treated with 4-methylpyridine. The changes observed were in many ways similar to those seen following administration of depressant compounds: increased latency of evoked potentials and increased latency to PTZ seizures. Not all findings, however, were consistent with previously observed patterns of central nervous system depression.
Dyer RS et al; Fundam Appl Toxicol 5 (5): 920-32 (1985)

12.1.10 Non-Human Toxicity Values

LD50 Rat oral 790 mg/kg
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520
LD50 Rat ip 200 mg/kg
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520
LD50 Mouse oral 674 mg/kg
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520
LD50 Rabbit skin 410 mg/kg
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520
LD50 Guinea pig oral 900 mg/kg
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 2520

12.1.11 TSCA Test Submissions

Acute toxicity was evaluated in groups of male Sprague-Dawley rats (4 groups of 10 animals each) ingesting a single dose of A-picoline via gavage at doses of 950, 790, 550 and 0 mg/kg. In the group given 950 mg/kg there was significantly increased mortality, (4 of 10 rats died), the remaining 6 rats showed decreased body weight gain, and 2 of the 6 also showed signs of encephalomalacia. Doses of 0 to 750 mg/kg had no significant toxic effects on test animals.
Dow Chemical Company; Acute Oral Toxicity of A-Picoline in Rats, Final Report. (1976), EPA Document No. 40-8341086, Fiche No. OTS0507474
Subchronic toxicity was evaluated in groups of male and female Sprague- Dawley rats (10/sex/concn level) exposed to A-picoline via inhalation in glass exposure chambers at nominal concentrations of 0, 5, 35 or 100 ppm, 5 days/week for 6 months, beginning at age 8 weeks. In male rats given 5 and 100 ppm there was significantly increased relative heart and liver weights. A statistically significant decrease in the red blood cell count was observed in both male and female rats exposed to the higher concentration of A-picoline (but this effect was not reproducible). Other parameters of clinical chemistry, urinalysis, and organ weights and histopathology were not consistently affected by the treatment.
Dow Chemical Company; Six Month Inhalation Study of A-Picoline in Rats, (1979), EPA Document No. 40-8341086, Fiche No. OTS0507474

12.2 Ecological Information

12.2.1 Ecotoxicity Values

LC50; Species: Pimephales promelas (fathead minnow); Conditions: flow-through bioassay with measured concentrations, 25.6 °C, dissolved oxygen 7.0 mg/L, hardness 46.0 mg/L CaCO3, alkalinity 309 mg/L CaCO3, and pH 7.88; Concentration: 897 mg/L for 96 hr (confidence limit not reliable)
Geiger D.L., Poirier S.H., Brooke L.T., Call D.J., eds. Acute Toxicities of Organic Chemicals to Fathead Minnows (Pimephales Promelas). Vol. III. Superior, Wisconsin: University of Wisconsin-Superior, 1986., p. 125
EC50; Species: Pimephales promelas (fathead minnow); Conditions: flow-through bioassay with measured concentrations, 25.6 °C, dissolved oxygen 7.0 mg/L, hardness 46.0 mg/L CaCO3, alkalinity 309 mg/L CaCO3, and pH 7.88; Concentration: 772 mg/L for 96 hr (confidence limit: 704-846 mg/L); Effect: loss of equilibrium
Geiger D.L., Poirier S.H., Brooke L.T., Call D.J., eds. Acute Toxicities of Organic Chemicals to Fathead Minnows (Pimephales Promelas). Vol. III. Superior, Wisconsin: University of Wisconsin-Superior, 1986., p. 125

12.2.2 Environmental Fate / Exposure Summary

2-Methylpyridine's production and use as a chemical intermediate in the synthesis of pharmaceuticals, dyes, rubber chemicals and vinyl pyridine, and as a solvent may result in its release to the environment through various waste streams. 2-Methylpyridine occurs in cigarette smoke. If released to air, a vapor pressure of 11.2 mm Hg at 25 °C indicates 2-methylpyridine will exist solely as a vapor in the ambient atmosphere. Vapor-phase 2-methylpyridine will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 6 days. 2-Methylpyridine does not absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight. If released to soil, 2-methylpyridine is expected to have very high to moderate mobility based upon Koc values ranging from 4 to 215. The pKa of 2-methylpyridine is 5.96, indicating that this compound will exist partially in the cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. In the soil tests, lowest adsorption occurred when 2-methylpyridine was in non-ionized form. Volatilization of the neutral species from moist soil surfaces is expected to be an important fate process based upon a Henry's Law constant of 9.96X10-6 atm-cu m/mole. 2-Methylpyridine is expected to volatilize from dry soil surfaces based upon its vapor pressure. Results of various biodegradation studies indicate that 2-methylpyridine generally biodegrades readily under aerobic conditions, but biodegradation occurs much slower under anaerobic conditions. 2-Methylpyridine was completely biodegraded in 2 weeks in one aerobic surface soil while in anaerobic surface soil only 10% biodegradation was reported in 3 months. If released into water, 2-methylpyridine is not expected to adsorb to suspended solids and sediment based upon the Koc values. Volatilization from water surfaces is expected to be an important fate process based upon this compound's Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 4 and 30 days, respectively. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. 2-Methylpyridine has been shown to biodegrade rapidly in aerobic groundwater with complete biodegradation observed after 4 days. In anaerobic estuarine sediment, 2-methylpyridine was not biodegraded over a 100-day period. Occupational exposure to 2-methylpyridine may occur through inhalation and dermal contact with this compound at workplaces where 2-methylpyridine is produced or used. Monitoring data indicate that the general population may be exposed to 2-methylpyridine via inhalation of ambient air, ingestion of food and drinking water. Since 2-methylpyridine has been identified as a component of cigarette smoke, people who smoke or inhale second-hand smoke may be exposed to higher levels of 2-methylpyridine than the general population. (SRC)
Methylpyridines' production and use as a chemical intermediate in the pharmaceutical, dye and resins industries and as a solvent in a variety of applications may result in their release to the environment through various waste streams. Methylpyridines are also released to the environment with the manufacture and use of coal-derived liquid fuels and during the disposal of coal liquefication and gasification waste byproducts. Methylpyridines occur in cigarette smoke. If released to air, vapor pressures ranging from 5.77 to 11.2 mm Hg at 25 °C for the three isomers indicate that methylpyridines will exist solely as a vapor in the ambient atmosphere. Vapor-phase methylpyridines will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 6-7 days. Methylpyridines do not absorb at wavelengths >290 nm and, therefore, are not expected to be susceptible to direct photolysis by sunlight. If released to soil, methylpyridines are expected to have high mobility based upon an estimated Koc of 115. The pKa of the methylpyridine isomers ranges 5.63 to 5.98, indicating that methylpyridines will exist partially in the cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. Koc can vary with pH with lowest adsorption occurring in the non-ionized form. Volatilization of the neutral species from moist soil surfaces is expected to be an important fate process based upon a Henry's Law constant range of 6.0X10-6 to 9.96X10-6 atm-cu m/mole. Methylpyridines are expected to volatilize from dry soil surfaces based upon the vapor pressure. Methylpyridines may biodegrade fairly rapidly under aerobic conditions in both soil and water. Methylpyridines are expected to be resistant to biodegradation under some anaerobic conditions. Acclimation of microbes may be important as demonstrated by complete degradation in 2 weeks in polluted soil versus 3 months in unpolluted soil. If released into water, methylpyridines are not expected to adsorb to suspended solids and sediment based upon the estimated Koc values. Volatilization from water surfaces is expected to be an important fate process based upon the Henry's Law constants of the three isomers. Estimated volatilization half-lives for a model river and model lake are 4 to 6 and 37 to 47 days, respectively. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since methylpyridines lack functional groups that hydrolyze under environmental conditions. In water, methylpyridines were rapidly biodegraded in acclimated aerobic natural waters with complete removal within 2 to 4 days. In sulfidogenic estuarine sediments, however, methylpyridine was not biodegraded over 200 days. Occupational exposure to methylpyridines may occur through inhalation and dermal contact with these compounds at workplaces where methylpyridines are produced or used or where coal-derived or petroleum fuels are produced or used. Monitoring data indicate that the general population may be exposed to methylpyridines via inhalation of ambient air, either passive or active inhalation of cigarette smoke, ingestion of food and drinking water, and dermal contact with products containing methylpyridines. (SRC)

12.2.3 Artificial Pollution Sources

2-Methylpyridine's production and use as a chemical intermediate in the synthesis of pharmaceuticals, dyes, rubber chemicals and vinyl pyridine, and as a solvent(1) may result in its release to the environment through various waste streams(SRC). In addition, 2-methylpyridine is found in cigarette smoke(2,3).
Underground coal gasification sites are a source of 2-methylpyridine.
Stuermer DH et al; Environ Sci Technol 16 (9): 582-7 (1982)
Methylpyridines production and use as a chemical intermediate in the pharmaceutical, dye and resins industries and as a solvent in a variety of applications(1) may result in its release to the environment through various waste streams(SRC). Methylpyridines are also released to the environment via effluents from the manufacture and use of coal-derived liquid fuels and the disposal of coal liquefication and gasification waste byproducts(2-5). Oil refineries(6), landfills(7,8) and municipal waste incinerators(9) release methylpyridine to the environment. In addition, methylpyridines are found in cigarette smoke(10,11).
(1) O'Neil MJ, ed; The Merck Index. 15 th ed., Cambridge, UK: Royal Society of Chemistry, p. 1374 (2013)
(2) Pelizzari E et al; ASTM Spec Tech Publ STP 686: 256-74 (1979)
(3) Giabbai, MF et al; Intern J Environ Anal Chem 20: 113-29 (1985)
(4) Dobson KR et al; Water Res 19: 849-56 (1985)
(5) Stetter JR et al; Environ Sci Technol 19: 924-8 (1985)
(6) Snider EH, Manning FS; Environ Int 7: 237-58 (1982)
(7) Dunlap WJ et al; Identif Anal Org Pollut 1: 453-77 (1975)
(8) Dunlap WJ et al; Organic Pollutants Contributed to Groundwater by a Landfill USEPA-600/9-76-004 p. 96-110 (1976)
(9) Junk GA, Ford CS; Chemosphere 9: 187-230 (1980)
(10) Guerin MR, Buchanan MV; Environ Exposure to N-Aryl Compounds, Carcinogenic and Mutagenic Responses to Aromatic Amines and Nitroarenes pp. 37-45 (1988)
(11) Rodgman A, Perfetti TA; The Chemical Components of Tobacco and Tobacco Smoke, Second Edition, CRC Press, Boca Raton, FL (2013)

12.2.4 Environmental Fate

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values ranging from 4 to 215, determined from sorption studies using 5 Eurosoil reference soils(2), indicate that 2-methylpyridine is expected to have very high to moderate mobility in soil(SRC). The pKa of 2-methylpyridine is 5.96(3), indicating that this compound will exist partially in cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). In the Eurosoil tests, lowest adsorption occurred when 2-methylpyridine was in non-ionized form(2). Volatilization of the neutral species of 2-methylpyridine from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 9.96X10-6 atm-cu m/mole(5). 2-Methylpyridine is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 11.2 mm Hg at 25 °C(6). Results of various biodegradation studies indicate that 2-methylpyridine generally biodegrades readily under aerobic conditions, but biodegradation occurs much slower under anaerobic ocnditions(7). In one aerobic soil study, 97.3% biodegradation of 2-methylpyridine occurred when incubated in a silt loam soil for 16 days(8). 2-Methylpyridine was completely biodegraded in 2 weeks in an aerobic surface soil while in anaerobic surface soil only 10% biodegradation was reported in 3 months(9).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) Bi E et al; Environ Sci Technol 40: 5962-5970 (2006)
(3) Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
(4) Doucette WJ; pp. 141-188 in Handbook of Property Estimation Methods for Chemicals. Boethling RS, Mackay D, eds. Boca Raton, FL: Lewis Publ (2000)
(5) Andon RJL et al; J Amer Chem Soc 76: 3188-96 (1954)
(6) Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
(7) European Commission; IUCLID Dataset, 2-Methylpyridine (CAS No. 109-06-8), Feb 8, 2000; Available from, as of Sept 19, 2014: https://esis.jrc.ec.europa.eu/doc/IUCLID/datasheet/109068.pdf
(8) Sims GK, Sommers LE; J Environ Qual 14: 580-4 (1985)
(9) Kaiser JP, Bollag JM; Soil Biol Biochem 24: 351-357 (1992)
AQUATIC FATE: Based on a classification scheme(1), Koc values ranging from 4 to 215, determined from sorption studies using 5 Eurosoil reference soils(2), indicate that 2-methylpyridine is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 9.96X10-6 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 4 and 30 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 3(SRC), from its log Kow of 1.11(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Low bioconcentration was reported for BCF tests using carp (Cyprinus carpio)(8). Results of various biodegradation studies indicate that 2-methylpyridine generally biodegrades readily under aerobic conditions, but biodegradation occurs much slower under anaerobic ocnditions(9). 2-Methylpyridine was completely biodegraded in 4 days in aerobic groundwater(10). In sulfidogenic estuarine sediments, 2-methylpyridine was not biodegraded over a 100-day period(11). 2-Methylpyridine is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). The UV absorption spectrum of 2-methylpyridine in aqueous solution shows no absorption >290 nm(12); therefore, 2-methylpyridine is not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) Bi E et al; Environ Sci Technol 40: 5962-5970 (2006)
(3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 15-1 to 15-29 (1990)
(4) Andon RJL et al; J Amer Chem Soc 76: 3188-96 (1954)
(5) Franke C et al; Chemosphere 29: 1501-14 (1994)
(6) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 20
(7) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.11. Nov, 2012. Available from, as of Sept 19, 2014: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(8) NITE; Chemical Risk Information Platform (CHRIP). Biodegradation and Bioconcentration. Tokyo, Japan: Natl Inst Tech Eval. Available from, as of Sept 19, 2014: https://www.safe.nite.go.jp/english/db.html
(9) European Commission; IUCLID Dataset, 2-Methylpyridine (CAS No. 109-06-8), Feb 8, 2000; Available from, as of Sept 19, 2014: https://esis.jrc.ec.europa.eu/doc/IUCLID/datasheet/109068.pdf
(10) Ronen et al; Ground Water 34: 194-99 (1996)
(11) Liu SM et al; Chemosphere 36: 2345-57 (1998)
(12) Andon RJL et al; Trans Faraday Soc 50: 918-927 (1954)
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2-methylpyridine, which has a vapor pressure of 11.2 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2-methylpyridine is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 6 days(SRC), calculated from its rate constant of 2.79X10-12 cu cm/molecule-sec at 25 °C(3). The UV absorption spectrum of 2-methylpyridine in aqueous solution shows no absorption >290 nm(4); therefore, 2-methylpyridine is not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988)
(2) Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
(3) NIST; NIST Chemistry WebBook. 2-Methylpyridine (109-06-8). NIST Standard Reference Database No. 69, June 2005 Release. Washington, DC: US Sec Commerce. Available from, as of Sept 19, 2014: https://webbook.nist.gov
(4) Andon RJL et al; Trans Faraday Soc 50: 918-927 (1954)
TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 115(SRC), determined from a structure estimation method(2), indicates that methylpyridines are expected to have high mobility in soil(SRC). The pKa of 2-, 3- and 4-methylpyridine are 5.96, 5.63 and 5.98, respectively(3), indicating that methylpyridines will exist partially in cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Soil studies with 2-methylpyridine(5) demonstrated that Koc can vary with pH with lowest adsorption occurring in the non-ionized form(5). Volatilization from moist soil surfaces is expected to be an important fate process(SRC) given Henry's Law constant values ranging from 6.0X10-6 to 9.96X10-6 atm-cu m/mole(6). Methylpyridines are expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure ranging from 5.77 to 11.2 mm Hg for the three isomers(7). Methylpyridines are expected to biodegrade fairly rapidly in aerobic soil; however, under anaerobic conditions, this compound may be persistent(8,9). 3-Methylpyridine and 4-methylpyridine were added to Fincastle silt loam; 69.3% (in 32 days) and 71.7% biodegradation to inorganic nitrogen (in 16 days), respectively, was observed(8). Methylpyridines are expected to be resistant to anaerobic biodegradation; no biodegradation was reported over 200 days in sulfidogenic sediments(10). Acclimation of microbes may be important as demonstrated by complete degradation of 4-methylpyridine in 2 weeks in polluted soil versus 3 months in unpolluted soil(9).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.11. Nov, 2012. Available from, as of Sept 23, 2014: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
(4) Doucette WJ; pp. 141-188 in Handbook of Property Estimation Methods for Chemicals. Boethling RS, Mackay D, eds. Boca Raton, FL: Lewis Publ (2000)
(5) Bi E et al; Environ Sci Technol 40: 5962-5970 (2006)
(6) Andon JRL et al; J Amer Chem Soc 76: 3188-96 (1954)
(7) Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
(8) Sims GK, Sommers LE; Environ Toxicol Chem 5: 503-9 (1985)
(9) Kaiser JP, Bollag JM; Soil Biol Biochem 24: 351-7 (1992)
(10) Liu SM et al; Chemosphere 36: 2345-57 (1998)
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 115(SRC), determined from a structure estimation method(2), indicates that methylpyridines are not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon Henry's Law constant values of 6.0X10-6 to 9.96X10-6 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 4 to 6 and 37 to 47, respectively(SRC). According to a classification scheme(5), an estimated BCF of 3(SRC), from log Kow values of 1.11, 1.20 and 1.22(6), for 2-, 3- and 4-methylpyridine, respectively, and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Methylpyridines may biodegrade fairly rapidly in aerobic waters; however, under anaerobic conditions, these compounds are expected to be persistent. In an aerobic river die-away test, 3- and 4-methylpyridine were rapidly biodegraded (complete biodegradation in 2 to 4 days) after acclimation in highly polluted natural waters(7). Methylpyridines areexpected to be resistant to anaerobic biodegradation; no biodegradation was reported over 200 days in sulfidogenic sediments(8). Methylpyridines are not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). The UV absorption spectrum of the methylpyridine isomers in aqueous solution shows no absorption >290 nm(9); therefore, methylpyridines are not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.11. Nov, 2012. Available from, as of Sept 23, 2014: 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. 7-4, 7-5, 15-1 to 15-29 (1990)
(4) Andon RJL et al; J Amer Chem Soc 76: 3188-96 (1954)
(5) Franke C et al; Chemosphere 29: 1501-14 (1994)
(6) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 20 (1995)
(7) Ettinger LA et al; Indus Eng Chem 46: 791-3 (1954)
(8) Liu SM et al; Chemosphere 36: 2345-57 (1998)
(9) Andon RJL et al; Trans Faraday Soc 50: 918-927 (1954)
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methylpyridines which have vapor pressure values of 11.2, 6.05, and 5.77 mm Hg at 25 °C(2) for the 2-, 3-, and 4-methylpyridine isomers, respectively, are expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methylpyridines aredegraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 6-7 days(SRC), calculated from the respective isomer rate constants of 2.79X10-12, 2.30X10-12 and 2.69X10-12 cu cm/molecule-sec at 25 °C(SRC)(3). The UV absorption spectrum of 2-, 3- and 4-methylpyridine in aqueous solution shows no absorption >290 nm(4); therefore, methylpyridines are not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988)
(2) Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
(3) NIST; NIST Chemistry WebBook. 2-, 3- and 4-Methylpyridine (109-06-8, 108-99-6, 108-89-4). NIST Standard Reference Database No. 69, June 2005 Release. Washington, DC: US Sec Commerce. Available from, as of Sept 24, 2014: https://webbook.nist.gov
(4) Andon RJL et al; Trans Faraday Soc 50: 918-927 (1954)

12.2.5 Environmental Biodegradation

AEROBIC: 2-Methylpyridine was reported as readily biodegradable in the MITI test(1). In an aerobic screening test using an enrichment culture obtained from soil as an inoculum, 100% degradation was obtained in 14 to 32 days(2). When this test was repeated under anaerobic conditions, degradation was much slower, requiring >97 days for complete biodegradation(2). Only 2.7% of the added 2-methylpyridine (initial concentration of 2 umoles/g) remained after 16 days following incubation in a silt loam soil(3). Complete biodegradation of 2-methylpyridine, initially added at 4 mg/L, was reported in aerobic groundwater incubated at 15 °C for 4 days(4). In an aerobic column study where subsurface sediment was leached with contaminated groundwater, 65% of the initially applied 2-methylpyridine was removed after 5 weeks of operation(5). Complete biodegradation of 2-methylpyridine was observed in 24 days following incubation in a defined medium inoculated with soil(6). Contaminated groundwater, from the American Creosote Works Superfund site in Pensacola, FL, was incubated with 2-methylpyridine; 33, 33, 33, 66, and 100% degradation was reported after incubation for 1, 3, 5, 8, and 14 days, respectively(7). 2-Methylpyridine, present at 100 mg/L, reached 0.1% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(8).
(1) Sasaki S; pp. 283-98 in Aquatic Pollutants, Transformation and Bio Effects. Hutzinger O et al, eds. Oxford, UK: Pergamon Press (1978)
(2) Naik MN et al; Soil Biol Biochem 4: 313-23 (1972)
(3) Sims GK, Sommers LE; J Environ Qual 14: 580-4 (1985)
(4) Ronen et al; Ground Water 34: 194-99 (1996)
(5) Ronen Z, Bollag JM; Intern J Environ Anal Chem 59: 133-43 (1995)
(6) Sims GK, Sommers LE Environ Toxicol Chem 5: 503-9 (1986)
(7) Mueller JG et al; Appl Environ Microbiol 57: 1277-85 (1991)
(8) NITE; Chemical Risk Information Platform (CHRIP). Biodegradation and Bioconcentration. Tokyo, Japan: Natl Inst Tech Eval. Available from, as of Sept 19, 2014: https://www.safe.nite.go.jp/english/db.html
ANAEROBIC: Complete biodegradation of 2-methylpyridine occurred within the first two weeks of exposure to unpolluted surface soil (with no pyridine derivatives) under aerobic conditions, but was unsuccessful under anaerobic conditions (both denitrifying and sulfidogenic conditions) with only 10% biodegradation reported in 3 months(1). 2-Methylpyridine was completely biodegraded within 2 weeks of exposure to contaminated (with pyridine derivatives) surface and subsurface soils under aerobic conditions(1). Under anaerobic conditions(both denitrifying and sulfidogenic conditions) in polluted soils, only 30% of the initially present 2-methylpyridine was degraded in 3 months. In sulfidogenic aquifer slurries, 97, 46, and <8% of the initially added 2-methylpyridine remained after 1, 3, and 8 months, respectively(2). In methanogenic aquifer slurries, 105, 107, and 97% 2-methylpyridine remained after 1, 3, and 8 months, respectively(2). 2-Methylpyridine was incubated in sulfidogenic estuarine sediments at concentrations from 70 to 80 uM; no biodegradation was reported over 200 days(3). In an anaerobic biodegradation study using sludge from a wastewater treatment plant digester as inoculum, 2-methylpyridine was found to have poor biodegradability(4).
(1) Kaiser JP, Bollag JM; Soil Biol Biochem 24: 351-357 (1992)
(2) Kuhn EP, Suflita JM; Environ Toxicol Chem 8: 1149-58 (1989)
(3) Liu SM et al; Chemosphere 36: 2345-57 (1998)
(4) Hongwei Y et al; Ecotoxicol Environ Saf 63: 299-305 (2006)
The fate of pyridine and 25 substituted pyridines in soil (Aeric Ochraqualfs) was examined by measuring the quantity remaining and the inorganic Nitrogen released as a result of degradation of the pyridine ring for a period of 64 days. Each compound was added to soil at 2 mmol kg/L. Compounds studied included pyridine substituted with one or two hydroxyl, carboxyl, chlorine, amine, or methyl groups. During the 64 day incubation, extractability of pyridine derivatives with 2 M potassium chloride 0.01 M hydrogen chloride decreased from an average of 88 + or - 8.8% to essentially 0 for all compounds except aminopyridines. ... Degradation of the majority of pyridine derivatives was confirmed by accumulation of nitrogen amounts equivalent to 61 to 80% of the decrease in extractable pyridines at 64 days of incubation. ... Aminopyridines resisted degradation in soil while methylpyridines were degraded in 8 to 32 days. Degradability of the compounds generally followed the order pyridine-carboxylic acids > pyridine = mono- hydroxypridines > methylpyridines > aminopyridines and chloropyridines.
Sims GK, Sommers LE; J Environ Qual 14 (4): 580-4 (1985)
AEROBIC: Less than 1% of an initial concentration of 12.7 ppm of 3-methylpyridine was mineralized within 30 days (measured as the release of inorganic nitrogen)(1). 68% of 4-methylpyridine, initially added at 15 ppm was mineralized within 24 days(1).
(1) Sims GK, Sommers LE; Appl Environ Microbiol 51: 963-8 (1986)
An aerobic soil grab sample study demonstrated rapid biodegradation of both 3- and 4-methylpyridine(1). However, the 3-methylpyridine was not biodegraded as rapidly as 4-methylpyridine, suggesting that a methyl group in the meta-position inhibits aerobic biodegradation. Methylpyridines were added to Fincastle silt loam (Aeric Ochraqualf) with a pH of 6.7 and incubated at 25 °C(1). Within 32 days, 69.3% of the available nitrogen from 3-methylpyridine was released to inorganic forms(1). Within 16 and 32 days, 71.7% and 100%, respectively, of the available nitrogen from 4-methylpyridine was released to inorganic forms(1). Respective sterilized controls lost 11.7% and 21.8% of the starting materials to volatilization; but, did not release inorganic nitrogen(1). An aerobic river die-away test also showed that 3- and 4-methylpyridine biodegraded rapidly after acclimation in highly polluted natural waters maintained at 20 °C(2). After 14- and 18-day acclimation periods, 100% of the original concentration of 1 ppm of 3-methylpyridine was removed within 2 and 4 days from the Ohio and Little Miami River waters, respectively(2). In groundwater samples collected near an oil shale facility(elevated alkylpyridine levels) no degradation occurred for 10 days after a soil inoculum was added; 3% remained at 17 days and <1% at 24 days. Without the soil inoculum, degradation was much slower and 19% remained at 31 days(3). Methylpyridines are only very slowly degraded in sulfur-reducing and methanogenic groundwater aquifer slurries; no degradation occurred after one month. 46% and <8% remained under sulfate-reducing conditions after 3 and 8 months, respectively, for the fastest reacting isomer (2-methylpyridine)(4). Methylpyridine isomers were incubated in sulfidogenic estuarine sediments at concentrations from 70 to 80 uM; no biodegradation was reported over 200 days for any isomer(5). In an anaerobic biodegradation study using sludge from a wastewater treatment plant digester as inoculum, 2-, 3- and 4-methylpyridine were found to have poor biodegradability(6).
(1) Sims GK, Sommers LE; Environ Toxicol Chem 5: 503-9 (1985)
(2) Ettinger LA et al; Indus Eng Chem 46: 791-3 (1954)
(3) Rodgers JE et al; Water Air Soil Pollut 24: 443-54 (1985)
(4) Kuhn EP, Suflita JM; Environ Toxicol Chem 8: 1149-58 (1989)
(5) Liu SM et al; Chemosphere 36: 2345-57 (1998)
(6) Hongwei Y et al; Ecotoxicol Environ Saf 63: 299-305 (2006)
Various biodegradation experiments were conducted in unpolluted (from the Savannah River plant site in SC) and polluted soil (contaminated with pyridine derivatives from a chemical plant in Indianapolis, IN) over a period of three months(1). Aerobic degradation of 2-, 3- and 4-methylpyridine was slow but complete within 2 months in unpolluted surface soil(1). Under denitrifying and sulfate-reducing conditions, approximately 40 to 50% and 10% degradation of 4-methylpyridine was reported in 3 months in an unpolluted surface and subsurface soil, respectively(1). In polluted aerobic surface and subsurface soils, degradation was complete within 2 weeks(1). Under denitrifying conditions, 65 and 20% degradation were reported after 3 months for polluted surface and subsurface soils, respectively; under sulfate-reducing conditions, 90 and 100% degradation was reported after 3 months for polluted surface and subsurface soils, respectively(1). Columns filled with aquifer material and leached with contaminated ground water from the Reilly site in Indianapolis, Indiana were run under aerobic conditions(2). 68.5% removal was observed after 35 days of operation(2).
(1) Kaiser JP, Bollag JM; Soil Biol Biochem 24: 351-57 (1992)
(2) Ronen Z et al; Ground Water 34: 194-99 (1996)

12.2.6 Environmental Abiotic Degradation

The rate constant for the vapor-phase reaction of 2-methylpyridine with photochemically-produced hydroxyl radicals has been measured as 2.79X10-12 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 6 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 2-Methylpyridine is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). The UV absorption spectrum of 2-methylpyridine in aqueous solution shows a UV maximum at 263 nm, but no absorption >290 nm(3); therefore, 2-methylpyridine is not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) NIST; NIST Chemistry WebBook. 2-Methylpyridine (109-06-8). NIST Standard Reference Database No. 69, June 2005 Release. Washington, DC: US Sec Commerce. Available from, as of Sept 18, 2014: https://webbook.nist.gov
(2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 7-5 (1990)
(3) Andon RJL et al; Trans Faraday Soc 50: 918-927 (1954)
The rate constant for the vapor-phase reaction of 2-, 3- and 4-methylpyridine with photochemically-produced hydroxyl radicals has been measured as 2.79X10-12, 2.30X10-12 and 2.69X10-12 cu cm/molecule-sec at 25 °C respectively(1). This corresponds to an atmospheric half-life of about 6-7 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Methylpyridines arenot expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). The UV absorption spectrum of 2-, 3- and 4-methylpyridine in aqueous solution shows a UV maximum at 253-263 nm, but no absorption >290 nm(3); therefore, methylpyridines are not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) NIST; NIST Chemistry WebBook. 2-, 3- and 4-Methylpyridine (109-06-8, 108-99-6, 108-89-4). NIST Standard Reference Database No. 69, June 2005 Release. Washington, DC: US Sec Commerce. Available from, as of Sept 24, 2014: https://webbook.nist.gov
(2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 7-5 (1990)
(3) Andon RJL et al; Trans Faraday Soc 50: 918-927 (1954)

12.2.7 Environmental Bioconcentration

An estimated BCF of 3 was calculated for 2-methylpyridine(SRC), using a log Kow of 1.11(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC). Low bioconcentration was reported for tests using carp (Cyprinus carpio)(4); however, actual BCF values were not available(SRC).
(1) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 20 (1995)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.11. Nov, 2012. Available from, as of Sept 19, 2014: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Franke C et al; Chemosphere 29: 1501-14 (1994)
(4) NITE; Chemical Risk Information Platform (CHRIP). Biodegradation and Bioconcentration. Tokyo, Japan: Natl Inst Tech Eval. Available from, as of Sept 19, 2014: https://www.safe.nite.go.jp/english/db.html
Estimated BCF values of 3 were calculated for methylpyridine(SRC), using log Kow values of 1.11, 1.20, and 1.22(1), for the 2-, 3-, and 4- methylpyridine isomers, and a regression-derived equation(2). According to a classification scheme(3), these BCF values suggest the potential for bioconcentration in aquatic organisms is low(SRC).[
(1) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 20 (1995)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.11. Nov, 2012. Available from, as of Sept 23, 2014: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Franke C et al; Chemosphere 29: 1501-14 (1994)

12.2.8 Soil Adsorption / Mobility

The sorption behavior of 2-methylpyridine was studied in soil column tests using 5 Eurosoil reference soils having organic carbon content ranging from 0.33-1.85% and pH ranging from 5.2-8.6(1); measured Kd values ranging from 0.08 to 6.52(1) correspond to calculated Koc values of 4, 38, 70, 100 and 215(SRC); the lowest Koc value of 4 corresponds to Eurosoil 2 which had the highest pH value(8.6). The pKa of 2-methylpyridine is 5.96(2), indicating that this compound will exist partially in cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(3). In the Eurosoil column tests(1), lowest adsorption occurred when 2-methylpyridine was in non-ionized form(1). Sorption of 2-methylpyridine to soil is primarily controlled by cation exchange and surface complex formation(1,4). According to a classification scheme(5), the Koc values suggest that 2-methylpyridine is expected to have very high to moderate mobility in soil.
(1) Bi E et al; Environ Sci Technol 40: 5962-5970 (2006)
(2) Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
(3) Doucette WJ; pp. 141-188 in Handbook of Property Estimation Methods for Chemicals. Boethling RS, Mackay D, eds. Boca Raton, FL: Lewis Publ (2000)
(4) Bi E et al; Environ Sci Technol 41: 3172-3178 (2006)
(5) Swann RL et al; Res Rev 85: 17-28 (1983)
Spectral studies of 2-methylpyridine adsorbed to hydrated and dehydrated silica indicate that hydrogen bonding occurs with silica surface silanols via the nitrogen atom on the pyridine ring and that this interaction is stronger than that between this compound and water(1). 2-Methylpyridine emerged under 2 soil column void volumes; soil columns were packed with soil cores from Rock Springs, WY to the original 1016 mm depth and shale-oil process water was used as the mobile phase(2); the pH and clay content of the soil were not specified(2); this indicates that soil is an effective adsorbent when less than this void volume of retort water is applied (as in small spills)(2); rainfall leaching after a spill will also probably enhance solute migration(2). When 2-methylpyridine was incubated at 28 °C in a soil inoculum, 4.8% was sorbed by soil(3).
(1) Ringwald SC, Pemberton JE; Environ Sci Technol 34: 259-65 (2000)
(2) Leenheer JA, Stuber HA; Environ Sci Technol 15: 1467-75 (1981)
(3) Sims GK, Sommers LE Environ Toxicol Chem 5: 503-9 (1986)
Using a structure estimation method based on molecular connectivity indices(1), the Koc of methylpyridine (all three isomers) can be estimated to be 115(SRC). According to a classification scheme(2), this estimated Koc value suggests that methylpyridines are expected to have high mobility in soil. The pKa values of 2-, 3-, and 4-methylpyridine are 5.96, 5.63 and 5.98, respectively(3), indicating that this compound will exist partially in cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Soil studies with 2-methylpyridine demonstrated that Koc can vary with pH with lowest adsorption occurring in the non-ionized form(5).
(1) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.11. Nov, 2012. Available from, as of Sept 23, 2014: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(2) Swann RL et al; Res Rev 85: 17-28 (1983)
(3) Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
(4) Doucette WJ; pp. 141-188 in Handbook of Property Estimation Methods for Chemicals. Boethling RS, Mackay D, eds. Boca Raton, FL: Lewis Publ (2000)
(5) Bi E et al; Environ Sci Technol 40: 5962-5970 (2006)

12.2.9 Volatilization from Water / Soil

The Henry's Law constant for 2-methylpyridine is 9.96X10-6 atm-cu m/mole(1). This Henry's Law constant indicates that 2-methylpyridine is expected to volatilize from water surfaces(2). 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)(2) is estimated as 4 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 30 days(SRC). 2-Methylpyridine's Henry's Law constant(1) indicates that volatilization from moist soil surfaces may occur(SRC). 2-Methylpyridine is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 11.2 mm Hg at 25 °C(3). 2-Methylpyridine is a weak base with a pKa of 5.96(4), which indicates this compound will partially exist in the protonated form in acidic conditions, and no volatilization from water or moist soil will occur for the cation(SRC). In mineral salts-soil suspensions incubated at 28 °C, 15% was volatilized in 24 days(5). Volatilization from soil alone was only 2-3% after 60 days(6).
(1) Andon RJL et al; J Amer Chem Soc 76: 3188-96 (1954)
(2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15-29 (1990)
(3) Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
(4) Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005.
(5) Sims GK, Sommers LE; Environ Toxicol Chem 5: 503-9 (1986)
(6) Sims GK, Sommers LE; J Environ Qual 14: 480-4 (1985)
Henry's Law constant values for the 2-, 3-, and 4-methylpyridine isomers are 9.96X10-6, 7.73X10-6 and 6.00X10-6 atm-cu m/mole, respectively(1). These Henry's Law constants indicate that methylpyridine is expected to volatilize from water surfaces(2). Based on these Henry's Law constant values, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 4 to 6 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 37 to 47 days(SRC). Methylpyridines' Henry's Law constants(1) indicate that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of methylpyridines from dry soil surfaces may exist(SRC) based upon vapor pressure values ranging from 5.77 to 11.2 mm Hg(3). Methylpyridines are weak bases with pKa values of 6.00(4), 5.63(5) and 5.98(5) for the 2-, 3-, and 4-methylpyridine isomers, respectively, indicating that these compound will partially exist in the protonated form in acidic conditions, and no volatilization from water or moist soil will occur for the cation(SRC).
(1) Andon RJL et al; J Chem Soc 76: 3188-96 (1954)
(2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15-29 (1990)
(3) Chao J et al; J Phys Chem Ref Data 12: 1033-63 (1983)
(4) Scriven EFV et al; Pyridine and Pyridine Derivatives. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2014). New York, NY: John Wiley & Sons. Online Posting Date: Dec 2, 2005

12.2.10 Environmental Water Concentrations

GROUNDWATER: Contaminated groundwater from St. Louis Park, MN - site of a coal tar distillation and wood-preserving facility that operated from 1918-1972 - contained 41 ppb of 2-methylpyridine(1). Two aquifers under the Hoe Creek (WY) coal gasification site contained 0.88-61 ppb of 2-methylpyridine 15 months after gasification was complete(2). 2-Methylpyridine was not detected in wells at Hanna and Gilette, WY prior to coal gasification(3). Concentrations of 0.91, and 0.34, 0.26, and 0.00 mg/L 2-methylpyridine at depths of 6.1, and 3.3, 5.8, and 11.0 meters, respectively, were reported in contaminated groundwater from two wood-preserving sites in Pensacola, FL(4). At Gas Works Park in Seattle, WA, 2-methylpyridine was found in only one of 10 wells at a concentration of 2.1 mg/L(5). 2-Methylpyridine was reported in groundwater sampled from 3 creosote-contaminated sites in Denmark at concentrations from not detected (detection limit of 0.05 ug/L) to 57 ug/L(6).
(1) Pereira WE et al; Environ Toxicol Chem 2: 283-94 (1983)
(2) Stuermer DH et al; Environ Sci Technol 16: 582-7 (1982)
(3) Pellizzari ED et al; Astm Spec Tech Publ, STP 686: 256-74 (1979)
(4) Goerlitz DF; Environ Sci Pollut Control Ser 4: 295-355 (1992)
(5) Turney GL, Goerlitz DF Ground Wat Monit Rev 10:187-98 (1990)
(6) Johansen SS et al; Groundwater Monit Rev 17: 106-15 (1997)
DRINKING WATER: 2-Methylpyridine was reported in drinking water in Cincinnati, OH(1).
(1) Lucas SV; GC/MS Analysis of Organics in Drinking Water Concentrations and Advanced Waste Treatment Concentrates Vol 1 USEPA-600/1-84-020A Columbus OH Eff Res Lab pp. 321 (1984)
SURFACE WATER: 2-Methylpyridine has been detected in Rhine River water at concentrations of 0, 0.012, 0.034, 0, 0, 0.012, 0.011, and 0 ug/L at 8 different locations(1). In 1979, 2-methylpyridine was detected in the River Rhine water at a concentration of 0.3 ug/L(2)
(1) Hendriks AJ et al; Wat Res 28: 581-98 (1994)
(2) Linders JBHJ et al; Inventory of Organic Substances in the River Rhine in 1979 NTIS PB83-200543 (1981)
DRINKING WATER: Methylpyridine was listed as a contaminant found in drinking water for a survey of US cities including Pomona, Escondido, Lake Tahoe and Orange Co, CA and Dallas, Washington, DC, Cincinnati, Philadelphia, Miami, New Orleans, Ottumwa, IA, and Seattle(1).
(1) Lucas SV; GC/MS Anal of Org in Drinking Water Concentrates and Advanced Treatment Concentrates Vol 1 USEPA-600/1-84-020A (NTIS PB85-128239) p. 397 (1984)
GROUNDWATER: 3- and 4-Methylpyridine were detected in 3 of 3 groundwater samples near a coal gasification site near Hoe Creek in northeastern WY at combined concentration of 0.69, 51 and 34 ppb(1). Leachate from a landfill in Norman, OK was reported to contaminant nearby groundwater supplies with unspecified isomers of methylpyridine(2,3).
(1) Stuermer DH et al; Environ Toxicol Chem 16: 582-7 (1982)
(2) Dunlap WJ et al; Identif Anal Org Pollut 1: 453-77 (1975)
(3) Dunlap WJ et al; Organic Pollutants contributed to groundwater by a Landfill USEPA-600/9-76-004 p. 96-110 (1976)

12.2.11 Effluent Concentrations

2-Methylpyridine has been identified in effluents from the following industries: timber products, organic chemicals, pharmaceuticals, and public owned treatment works(3). 2-Methylpyridine is contained in shale oil wastewater (5 ppm) and would be released to the atmosphere if the wastewater were heated as it would be when used to cool hot, retorted oil shale(1,5). It was also found in the effluents from an advanced publically-owned water treatment facility in Pomona, CA(2). Wastewater from coal gasification contained an estimated 3.71 ppm of 2-methylpyridine(4). 2-Methylpyridine has been detected at a mean concentration of 5.0 mg/L from 10 samples of low temperature carbonization wastewater from waste ammonia liquor(6).
(1) Hawthorne SB et al; Environ Sci Tech 19: 922-7 (1985)
(2) Lucas SV; GC/MS Analysis of Organics in Drinking Water Concentrations and Advanced Waste Treatment Concentrates Vol 1, USEPA-600/1-84-020A pp. 321 (1984)
(3) Shackelford WM et al; Analyt Chem Acta 146: 15-27 (1983)
(4) Giabbai MF et al; Int J Environ Anal Chem 20: 113-29 (1985)
(5) Dobson KR et al; Water Res J 19: 849-56 (1985)
(6) Pandey RA et al; J Environ Sci Health A24: 603-32 (1989)
The 2-, 3- and 4-isomers of methylpyridine were detected in 6 of 18 wastewater effluents from energy related processes(1). Retort water from a shale oil processing facility in DeBeque, CO contained the 2- and 3-methylpyridine isomers at average concentration of 36 ppb(1). The process water at a coal gasification facility in Gillette, WY contained the 2- and 3-methylpyridine at an average concentration of 49 ppb(1). An underground coal gasification site contained 2-methylpyridine at an average concentration 120 ppb(1). Wastewater from coal gasification at the Grand Fork's Energy Technology Center, ND was reported to contain 3- and 4-methylpyridine at an estimated combined concentration of 2.53 mg/L(2). Wastewater effluent from a shale oil facility in Queensland, Australia was shown to contain 3- and 4-methylpyridine in a combined concentration of 4 mg/L(3). Reactor tar from a coal gasification plant contained unidentified isomers of methylpyridine at a concentration ranging from 5.5 to 12.4 mg/g(4).
(1) Pelizzari E et al; ASTM Spec Tech Publ STP 686: 256-74 (1979)
(2) Giabbai, MF et al; Intern J Environ Anal Chem 20: 113-29 (1985)
(3) Dobson KR et al; Water Res 19: 849-56 (1985)
(4) Stetter JR et al; Environ Sci Technol 19: 924-8 (1985)
The dissolved air floatation effluent of a Class B oil refinery contained unidentified isomers of methylpyridine at a concentration less than 1 ng/g(1). Unspecified isomers of methylpyridine were detected in 5 and 3 of 63 industrial wastewater effluents at concentration ranging from 10 to 100 ug/L and greater than 100 ug/L, respectively(2). Unspecified isomers of methylpyridine were detected in the ground water leachate of a landfill in Norman, OK(3,4). Methylpyridine was listed as a component of grate ash from municipal waste incinerators(5).
(1) Snider EH, Manning FS; Environ Int 7: 237-58 (1982)
(2) Perry DL et al; Iden of Org Compounds in Ind Effluent discharges USEPA-600/4-79-016 (NTIS PB-294794) p. 230 (1979)
(3) Dunlap WJ et al; Ident Anal Org Pollut 1: 453-77 (1975)
(4) Dunlap WJ et al; Organic Pollutants contributed to groundwater by a Landfill USEPA-600/9-76-004 p. 96-110 (1976)
(5) Junk GA, Ford CS; Chemosphere 9: 187-230 (1980)

12.2.12 Sediment / Soil Concentrations

2-Methylpyridine was detected but not quantified in non-agricultural loamy soil from the Moscow region(1). Less than 0.22 ppm of the chemical was found in Eagle Harbor sediment, an area of Puget Sound that is contaminated with creosote(2).
(1) Golovnya RV et al; USSR Acad Med Sci pp. 325-35 (1982)
(2) Krone CA et al; Environ Sci Technol 20: 1144 (1986)

12.2.13 Atmospheric Concentrations

INDOOR: A mean concentration of 0.07 ug/cu m 2-methylpyridine was reported in samples of air taken from non-smoking homes in Columbus, OH over one week in February 1991 (n=24; range=0.00 to 0.67 ug/cu m); in smoking homes, a mean concentration of 0.45 ug/cu 2-methylpyridine was reported (n=25; range=0.00 to 1.55 ug/cu m)(1).
(1) Heavner DL et al; Environ Internat 21: 3-21 (1995)
SOURCE DOMINATED: Indoor and outdoor air in and near the shale oil wastewater treatment facility of Occidental Oil Shale Inc at the Logan Wash site, CO contained 7 and 28 ug/cu m of 2-methylpyridine, respectively(1). Rural air in an undeveloped area of the oil shale region as well as urban air (Boulder, CO) contained no 2-methylpyridine(1). The average daily ambient concentration for 2-methylpyridine based on 3 data points is 0.613 ppbv(2).
(1) Hawthorne SB, Sievers RE; Environ Sci Technol 18: 483-90 (1984)
(2) Shah JJ, Heyerdahl EK; National Ambient Volatile Organic Compounds (VOCs) Database Update USEPA/6600/3-88/010 (1988)
URBAN: Methylpyridine was not detected in the air of downtown Boulder, CO in Nov. 1982(1).
(1) Hawthorne SB, Sievers RE; Environ Sci Technol 18: 483-90 (1984)
RURAL: Methylpyridine was not detected in air from an undeveloped location of CO in Nov. 1982(1).
(1) Hawthorne SB, Sievers RE; Environ Sci Technol 18: 483-90 (1984)
SOURCE DOMINATED: In Nov. 1982, 3-and 4-methylpyridine were detected in the air outside an oil shale wastewater facility of Occidental Oil Shale Inc. at Logan Wash, CO at a combined average concentration of 8 ug/cu m(1).
(1) Hawthorne SB, Sievers RE; Environ Sci Technol 18: 483-90 (1984)

12.2.14 Food Survey Values

2-Methylpyridine has been identified as a volatile flavor compound in fried bacon(1), boiled beef(2), fried chicken(3) and frankfurters(4). 2-Methylpyridine has also been detected in coffee aroma(5) and identified as an aroma compound in the earth almond(6). Concentrations of 2-methylpyridine in 3 commercial fermented soybean curds from Hong Kong were 25.8, 17.2, and 99.7 ug/kg(7).
(1) Ho CT et al; J Agric Food Chem 31: 336-42 (1983)
(2) Golovnya RV et al; Chem Senses Flavour 4: 97-105 (1979)
(3) Aeshbacher HU et al; Fd Chem Toxic 27: 227-32 (1989)
(4) Tang J et al; J Agric Food Chem 31: 1287-92 (1983)
(5) Cantalejo MJ; J Agric Food Chem 45: 1853-60 (1997)
(6) Cha YJ, Cadwallader KR; J Food Sci 60: 19-24 (1995)
(7) Chung HY; J Agric Food Chem 47: 2690-2696 (1999)
2-, 3- and 4-Methylpyridine were identified as volatile components of boiled beef(1), fried bacon(2) and pork(3).
(1) Golovnya RV, et al; Chem Senses Flavour 4: 97-105 (1979)
(2) Ho CT et al; J Agric Food Chem 31: 336-42 (1983)
(3) Shahidi F et al; CRC Crit Rev Food Sci Nature 24: 141-243 (1986)

12.2.15 Fish / Seafood Concentrations

Mean concentrations of 2-methylpyridine in Korean salt-fermented fish pastes were 146, 203, and 292 ng/g for anchovy, big-eyed herring and shrimp pastes, respectively(1). 2-Methylpyridine was reported as a volatile in the leg meat, body meat, and carapace meat of Charybdis feriatus, a popularly consumed edible crab in Asia at concentrations of 5.5, 2.6, and 4.5 ug/kg, respectively(2). 2-Methylpyridine was reported as a volatile compound in fish sauce from Southeast Asia(3).
(1) Chevance FFV, Farmer LJ; J Agric Food Chem 47: 5151-5160 (1999)
(2) Chung HY; J Agric Food Chem 47: 2280-87 (1999)
(3) Fukami K et al; J Agric Food Chem 50: 5412-5416 (2002)

12.2.16 Other Environmental Concentrations

2-Methylpyridine has been identified in cigarette smoke(1,2). It was detected, not quantified in marijuana smoke(3).
(1) Graedel TE; Chemical Compounds in the Atmosphere. NY, NY: Academic Press p. 22 (1978)
(2) Singer BC et al; Environ Sci Technol 36: 846-853 (2002)
(3) CA EPA; Evidence of the Carcinogenicity of Marjuana Smoke. August 2009. California Off Environ Health Assess. Available from, as of Sept 25, 2014: https://oehha.ca.gov/prop65/hazard_ident/pdf_zip/FinalMJsmokeHID.pdf
Methylpyridine was detected in cigarette smoke(1,2).
(1) Guerin MR, Buchanan MV; Environ Exposure to N-Aryl Compounds, Carcinogenic and Mutagenic Responses to Aromatic Amines and Nitroarenes p. 37-45 (1988)
(2) Rodgman A, Perfetti TA; The Chemical Components of Tobacco and Tobacco Smoke, Second Edition, CRC Press, Boca Raton, FL (2013)

12.2.17 Probable Routes of Human Exposure

According to the 2006 TSCA Inventory Update Reporting data, the number of persons reasonably likely to be exposed in the industrial manufacturing, processing, and use of 2-methylpyridine is 1 to 99; the data may be greatly underestimated(1).
(1) US EPA; Inventory Update Reporting (IUR). Non-confidential 2006 IUR Records by Chemical, including Manufacturing, Processing and Use Information. Washington, DC: U.S. Environmental Protection Agency. Available from, as of Sept 20, 2014: https://cfpub.epa.gov/iursearch/index.cfm
NIOSH (NOES Survey 1981-1983) has statistically estimated that 11,240 workers (1,234 of these were female) were potentially exposed to 2-methylpyridine in the US(1). Occupational exposure to 2-methylpyridine may occur through inhalation and dermal contact with this compound at workplaces where 2-methylpyridine is produced or used(SRC). 2-Methylpyridine is formed in the thermal decomposition of amine-cured epoxy powder paint and this could lead to occupational exposures if the epoxy resin is deposited on a surface hot enough to degrade the polymer (350 °C)(2). Monitoring data indicate that the general population may be exposed to 2-methylpyridine via inhalation of ambient air, ingestion of food and contaminated drinking water, and inhalation of cigarette smoke(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 Sept 20, 2014: https://www.cdc.gov/noes/
(2) Peltonen K; J Anal Appl Pyrolysis 10: 51-7 (1986)
PICOLINES CAN BE ABSORBED BY INHALATION, INGESTION, AND SKIN CONTACT. /PICOLINES/
International Labour Office. Encyclopedia of Occupational Health and Safety. Vols. I&II. Geneva, Switzerland: International Labour Office, 1983., p. 1811
Workers in plants where 2-methylpyridine is produced from acetaldehyde and ammonia, and those at plants extracting the compound from coke oven by-products have a high exposure potential. ... Worker exposure may also occur in related industries such as tar and pitch plants where the compound has also been found in air samples, ... and also in energy industries such as coal gasification and liquefaction and oil shale extraction where pyridines have been found in waste waters. Workers in industries using 2-methylpyridine as a chemical intermediate in the manufacture of polymer adhesives, acrylic fibers, vinyl resins, pesticides and pharmaceuticals might also be exposed, but no monitoring data were found to determine the extent of such exposures.
ITC/USEPA; Information Review #425 (Draft) Methylpyridines p.31-32 (1984)
THE CONCN OF PICOLINE IN THE WORKPLACE AIR OF IRONWORKS AND COKING PLANTS WAS LESS THAN 5 MG/CU M.
MASEK V; STAUB--REINHALT LUFT 41 (1): 26 (1981)
NIOSH (NOES Survey 1981-1983) has statistically estimated that 11,240 workers (1,234 of these were female), 5,202 workers (390 of these were female) and 9,577 workers (1,118 of these were female) were potentially exposed to 2-, 3- and 4-methylpyridine, respectively, in the US(1). Occupational exposure to methylpyridines may occur through inhalation and dermal contact with these compounds at workplaces where methylpyridinesis produced or used(SRC). Monitoring data indicate that the general population may be exposed to methylpyridines via inhalation of ambient air, inhalation of cigarette smoke, ingestion of food and contaminated drinking water, and dermal contact with products containing methylpyridines(SRC). A 1982 study showed 3- and 4-methylpyridine were emitted to the air from waste waters at a shale oil facility exposing inside workers to combined average concentration of 35 ug/cu m(2).
(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 Sept 25, 2014: https://www.cdc.gov/noes/
(2) Hawthorne SB, Sievers RE; Environ Sci Technol 18: 483-90 (1984)

13 Literature

13.1 Consolidated References

13.2 NLM Curated PubMed Citations

13.3 Springer Nature References

13.4 Thieme References

13.5 Wiley References

13.6 Nature Journal References

13.7 Chemical Co-Occurrences in Literature

13.8 Chemical-Gene Co-Occurrences in Literature

13.9 Chemical-Disease Co-Occurrences in Literature

14 Patents

14.1 Depositor-Supplied Patent Identifiers

14.2 WIPO PATENTSCOPE

14.3 Chemical Co-Occurrences in Patents

14.4 Chemical-Disease Co-Occurrences in Patents

14.5 Chemical-Gene Co-Occurrences in Patents

15 Interactions and Pathways

15.1 Chemical-Target Interactions

16 Biological Test Results

16.1 BioAssay Results

17 Taxonomy

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

18 Classification

18.1 MeSH Tree

18.2 ChEBI Ontology

18.3 ChemIDplus

18.4 CAMEO Chemicals

18.5 ChEMBL Target Tree

18.6 UN GHS Classification

18.7 EPA CPDat Classification

18.8 NORMAN Suspect List Exchange Classification

18.9 EPA DSSTox Classification

18.10 EPA TSCA and CDR Classification

18.11 LOTUS Tree

18.12 EPA Substance Registry Services Tree

18.13 MolGenie Organic Chemistry Ontology

19 Information Sources

  1. Australian Industrial Chemicals Introduction Scheme (AICIS)
  2. CAMEO Chemicals
    LICENSE
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    https://cameochemicals.noaa.gov/help/reference/terms_and_conditions.htm?d_f=false
    CAMEO Chemical Reactivity Classification
    https://cameochemicals.noaa.gov/browse/react
  3. ILO-WHO International Chemical Safety Cards (ICSCs)
  4. CAS Common Chemistry
    LICENSE
    The data from CAS Common Chemistry is provided under a CC-BY-NC 4.0 license, unless otherwise stated.
    https://creativecommons.org/licenses/by-nc/4.0/
  5. ChemIDplus
    ChemIDplus Chemical Information Classification
    https://pubchem.ncbi.nlm.nih.gov/source/ChemIDplus
  6. DTP/NCI
    LICENSE
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    https://www.cancer.gov/policies/copyright-reuse
  7. EPA Chemical Data Reporting (CDR)
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    https://www.epa.gov/web-policies-and-procedures/epa-disclaimers#copyright
  8. EPA Chemicals under the TSCA
    EPA TSCA Classification
    https://www.epa.gov/tsca-inventory
  9. EPA DSSTox
    CompTox Chemicals Dashboard Chemical Lists
    https://comptox.epa.gov/dashboard/chemical-lists/
  10. European Chemicals Agency (ECHA)
    LICENSE
    Use of the information, documents and data from the ECHA website is subject to the terms and conditions of this Legal Notice, and subject to other binding limitations provided for under applicable law, the information, documents and data made available on the ECHA website may be reproduced, distributed and/or used, totally or in part, for non-commercial purposes provided that ECHA is acknowledged as the source: "Source: European Chemicals Agency, http://echa.europa.eu/". Such acknowledgement must be included in each copy of the material. ECHA permits and encourages organisations and individuals to create links to the ECHA website under the following cumulative conditions: Links can only be made to webpages that provide a link to the Legal Notice page.
    https://echa.europa.eu/web/guest/legal-notice
  11. FDA Global Substance Registration System (GSRS)
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    https://www.fda.gov/about-fda/about-website/website-policies#linking
  12. Hazardous Substances Data Bank (HSDB)
  13. Human Metabolome Database (HMDB)
    LICENSE
    HMDB 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 (HMDB) and the original publication (see the HMDB citing page). We ask that users who download significant portions of the database cite the HMDB paper in any resulting publications.
    http://www.hmdb.ca/citing
  14. New Zealand Environmental Protection Authority (EPA)
    LICENSE
    This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International licence.
    https://www.epa.govt.nz/about-this-site/general-copyright-statement/
  15. NJDOH RTK Hazardous Substance List
  16. Risk Assessment Information System (RAIS)
    LICENSE
    This work has been sponsored by the U.S. Department of Energy (DOE), Office of Environmental Management, Oak Ridge Operations (ORO) Office through a joint collaboration between United Cleanup Oak Ridge LLC (UCOR), Oak Ridge National Laboratory (ORNL), and The University of Tennessee, Ecology and Evolutionary Biology, The Institute for Environmental Modeling (TIEM). All rights reserved.
    https://rais.ornl.gov/
  17. 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
  18. ChEBI
  19. 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/
  20. Yeast Metabolome Database (YMDB)
    LICENSE
    YMDB is offered to the public as a freely available resource.
    http://www.ymdb.ca/downloads
  21. 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
  22. Comparative Toxicogenomics Database (CTD)
    LICENSE
    It is to be used only for research and educational purposes. Any reproduction or use for commercial purpose is prohibited without the prior express written permission of NC State University.
    http://ctdbase.org/about/legal.jsp
  23. Crystallography Open Database (COD)
    LICENSE
    All data in the COD and the database itself are dedicated to the public domain and licensed under the CC0 License. Users of the data should acknowledge the original authors of the structural data.
    https://creativecommons.org/publicdomain/zero/1.0/
  24. The Cambridge Structural Database
  25. EPA Chemical and Products Database (CPDat)
  26. EU Food Improvement Agents
  27. Hazardous Chemical Information System (HCIS), Safe Work Australia
  28. NITE-CMC
    2-methylpyridine; 2-picoline - FY2008 (New/original classication)
    https://www.chem-info.nite.go.jp/chem/english/ghs/08-mhlw-0162e.html
    2-Methylpyridine (2-Picoline) - FY2018 (Revised classification)
    https://www.chem-info.nite.go.jp/chem/english/ghs/18-mhlw-2021e.html
  29. 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
  30. 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
  31. IUPAC Digitized pKa Dataset
  32. NMRShiftDB
  33. MassBank Europe
  34. 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
  35. 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
  36. SpectraBase
  37. Japan Chemical Substance Dictionary (Nikkaji)
  38. 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
  39. KNApSAcK Species-Metabolite Database
  40. Natural Product Activity and Species Source (NPASS)
  41. Kruve Lab, Ionization & Mass Spectrometry, Stockholm University
    2-methylpyridine
  42. Metabolomics Workbench
  43. Nature Chemistry
  44. 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/
    Picoplatin
    NORMAN Suspect List Exchange Classification
    https://www.norman-network.com/nds/SLE/
  45. Springer Nature
  46. SpringerMaterials
  47. 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/
  48. Wikidata
  49. Wikipedia
  50. Wiley
  51. PubChem
  52. 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
  53. GHS Classification (UNECE)
  54. EPA Substance Registry Services
  55. MolGenie
    MolGenie Organic Chemistry Ontology
    https://github.com/MolGenie/ontology/
  56. PATENTSCOPE (WIPO)
CONTENTS