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4-Pyridinol, 3,5-dichloro-2,6-dimethyl-

RTECS #
UU7711500
CAS #
2971-90-6; 68821-99-8
See: NMAM or OSHA Methods
Updated
September 2013
Molecular Weight
192.05
Molecular Formula
C7H7Cl2NO
Synonyms
3,5-Dichloro-2,6-dimethyl-4-pyridinol
Clopidol
Clopidol (ACGIH:OSHA)
Coccidiostat C
Coyden
Coyden 25
Lerbek
Methylchloropindol
Methylchlorpindol
Meticlorpindol

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
oral/guinea pig lethal dose (50 percent kill): >8 gm/kg85INA8 6,324,1991
oral/rabbit lethal dose (50 percent kill): >8 gm/kg85INA8 6,324,1991
oral/rat lethal dose (50 percent kill): 18 gm/kg85KYAH 11,375,1989

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 3 ppm (inhal, vapor)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWTOLED5 142,207,2003

Standards and Regulations

OrganizationStandardReference
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIAtime-weighted average 10 mg/m3, JUL2008
Occupational Exposure Limit-BELGIUMtime-weighted average 10 mg/m3, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 10 mg/m3, MAY2011
Occupational Exposure Limit-FRANCEVME 10 mg/m3, FEB2006
Occupational Exposure Limit-ICELANDtime-weighted average 10 mg/m3, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 10 mg/m3, short term exposure limit 20 mg/m3, 2006
Occupational Exposure Limit-MEXICOtime-weighted average 10 mg/m3;short term exposure limit 20 mg/m3, 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 10 mg/m3, JAN2002
Occupational Exposure Limit-PERUtime-weighted average 10 mg/m3, JUL2005
Occupational Exposure Limit-SWITZERLANDMAK-week 10 mg/m3, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 10 mg/m3, 2003
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 15 mg/m3, total dustCFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 5 mg/m3, respirable fractionCFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 15 mg/m3, total dustCFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 5 mg/m3, respirable fractionCFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 15 mg/m3, total dustCFRGBR 29,1915.1000,1993
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 5 mg/m3, respirable fractionCFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO CLOPIDOL, respirable fraction-air10H time-weighted average 5 mg/m3NIOSH* DHHS #95-121,1995
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO CLOPIDOL, total dust-air10H time-weighted average 10 mg/m3;short term exposure limit 20 mg/m3NIOSH* DHHS #95-121,1995
Page last reviewed: November 16, 2018