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Registry of Toxic Effects of Chemical Substances (RTECS)

Hydrocyanic acid

RTECS #

MW6825000

CAS #

74-90-8

Updated

September 201

Molecular Weight

27.03

Molecular Formula

CHN

Synonyms

Acide cyanhydrique (French)
Acido cianidrico (Italian)
Aero Liquid HCN
Blausaeure (German)
Blauwzuur (Dutch)
Carbon hydride nitride (chn)
Cyaanwaterstof (Dutch)
Cyanwasserstoff (German)
Cyclon
Cyclone B
Cyjanowodor (Polish)
Evercyn
Formic anammonide
Formonitrile
Hydrogen cyanide
Hydrogen cyanide (ACGIH:OSHA)
Prussic acid
Prussic acid, unstabilized
RCRA waste number P063
Zaclondiscoids

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/cat Lowest published lethal concentration: 550 mg/m3VCVN1* -,334,1988
inhalation/human lowest published toxic concentration: 20 mg/m3Gastrointestinal: Nausea or vomiting

Cardiac: Pulse rate decreased with fall in BP
VCVN1* -,334,1988
inhalation/human Lowest published lethal concentration: 100 mg/m3/1HBrain and Coverings: Changes in circulation

Liver: Other changes

Kidney, Ureter, and Bladder: Other changes
VCVN1* -,334,1988
inhalation/human Lowest published lethal concentration: 120 mg/m3/30MBrain and Coverings: Changes in circulation

Liver: Other changes

Kidney, Ureter, and Bladder: Other changes
VCVN1* -,334,1988
inhalation/human Lowest published lethal concentration: 200 mg/m3/10MBrain and Coverings: Changes in circulation

Liver: Other changes

Kidney, Ureter, and Bladder: Other changes
VCVN1* -,334,1988
inhalation/human Lowest published lethal concentration: 200 mg/m3/10MBehavioral: General anesthetic

Lung, Thorax, or Respiration: Dyspnea

Gastrointestinal: Nausea or vomiting
WHOTAC -,30,1970
inhalation/human lowest published toxic concentration: 5 mg/m3Behavioral: HeadacheTOVEFN (2),39,2001
inhalation/human lowest published toxic concentration: 20 mg/m3Cardiac: Pulse rate increased without fall in BP

Gastrointestinal: Nausea or vomiting
TOVEFN (2),39,2001
inhalation/human Lowest published lethal concentration: 100 mg/m3/1HTOVEFN (2),39,2001
inhalation/human Lowest published lethal concentration: 120 mg/m3/30MTOVEFN (2),39,2001
inhalation/human Lowest published lethal concentration: 200 mg/m3/10MTOVEFN (2),39,2001
inhalation/mammal (species unspecified) Lowest published lethal concentration: 200 ppm/5MAEPPAE 138,65,1928
inhalation/mammal (species unspecified) Lowest published lethal concentration: 36 ppm/2HTABIA2 3,231,1933
inhalation/man Lowest published lethal concentration: 400 mg/m3/2M85GMAT -,75,1982
inhalation/man lowest published toxic concentration: 500 mg/m3/3M-continuousEye: Mydriasis (pupilliary dilation)

Behavioral: Coma

Lung, Thorax, or Respiration: Respiratory depression
HUTODJ 3,57,1984
inhalation/monkey lowest published toxic concentration: 17 ppm/10MBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Respiratory stimulation
TOXID9 72,159,2003
inhalation/monkey lowest published toxic concentration: 10 ppm/30MBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Respiratory stimulation
TOXID9 72,159,2003
inhalation/monkey lowest published toxic concentration: 7.1 ppm/1HBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Respiratory stimulation
TOXID9 72,159,2003
inhalation/monkey lowest published toxic concentration: 3.5 ppm/4HBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Respiratory stimulation
TOXID9 72,159,2003
inhalation/monkey lowest published toxic concentration: 2.5 ppm/8HBrain and Coverings: Other degenerative changes

Lung, Thorax, or Respiration: Respiratory stimulation
TOXID9 72,159,2003
inhalation/mouse lethal concentration (50 percent kill): 323 ppm/5MTXAPA9 42,417,1977
inhalation/mouse lethal concentration (50 percent kill): 177 ppm/29MENTOX* -,698,2005
inhalation/mouse lethal concentration (50 percent kill): 48.65 mg/m3/2HTPKVAL 9,7,1967
inhalation/mouse lethal concentration (50 percent kill): 45.3 ppm/2HTPKVAL 9,7,1967
inhalation/rabbit lethal concentration (50 percent kill): 208 mg/m3/35MBrain and Coverings: Other degenerative changes

Cardiac: Other changes

Blood: Other changes
TSUJDP 13,263,1994
inhalation/rat lethal concentration (50 percent kill): 150 ppm/30MENTOX* -,639,2005
inhalation/rat Lowest published lethal concentration: 138 ppm/15MTOXID9 72,159,2003
inhalation/rat Lowest published lethal concentration: 127 ppm/30MTOXID9 72,159,2003
inhalation/rat Lowest published lethal concentration: 88 ppm/1HTOXID9 72,159,2003
inhalation/rat lowest published toxic concentration: 10 ppmEar: Change in acuity

Ear: Change in cochlear structure or function
TOSCF2 66,131,2002
intramuscular/mouse lethal dose (50 percent kill): 2700 µg/kgBJPCAL 23,455,1964
intramuscular/pigeon lowest published lethal dose: 1500 µg/kgFDWU** -,-,1931
intramuscular/rabbit lethal dose (50 percent kill): 486 µg/kgJACTDZ 1(3),120,1982
intraperitoneal/mouse lethal dose (50 percent kill): 2990 µg/kgBJPCAL 23,455,1964
intraperitoneal/rabbit lethal dose (50 percent kill): 1570 µg/kgBJPCAL 23,455,1964
intravenous/cat lethal dose (50 percent kill): 810 µg/kgNTIS** AD-A028-501
intravenous/Dog lethal dose (50 percent kill): 1340 µg/kgNTIS** AD-A028-501
intravenous/domestic animal lethal dose (50 percent kill): 660 µg/kgNTIS** PB158-508
intravenous/guinea pig lethal dose (50 percent kill): 1430 µg/kgNTIS** AD-A028-501
intravenous/man lowest published toxic dose: 55 µg/kgLung, Thorax, or Respiration: Respiratory stimulationNTIS** PB158-508
intravenous/monkey lethal dose (50 percent kill): 1300 µg/kgNTIS** AD-A028-501
intravenous/mouse lethal dose (50 percent kill): 990 µg/kgNTIS** AD-A028-501
intravenous/rabbit lethal dose (50 percent kill): 660 µg/kgNTIS** AD-A028-501
intravenous/rat lethal dose (50 percent kill): 810 µg/kgNTIS** AD-A028-501
ocular/rabbit lethal dose (50 percent kill): 1040 µg/kgEye: Other eye effects

Behavioral: Ataxia

Lung, Thorax, or Respiration: Respiratory stimulation
JTOTDO 2,119,1983
oral/Dog lowest published lethal dose: 4 mg/kgHBAMAK 4,1340,1935
oral/domestic bird lowest published lethal dose: 600 µg/kgFDWU** -,-,1931
oral/duck lowest published lethal dose: 3280 µg/kgFDWU** -,-,1931
oral/human lowest published lethal dose: 570 µg/kgPCOC** -,596,1966
oral/mouse lethal dose (50 percent kill): 3700 µg/kgAPFRAD 19,740,1961
oral/pig lowest published lethal dose: 2 mg/kgAEHLAU 22,496,1971
oral/pigeon lowest published lethal dose: 14 mg/kgFDWU** -,-,1931
oral/rabbit lowest published lethal dose: 4 mg/kgHBAMAK 4,1340,1935
oral/wild bird lowest published lethal dose: 7500 µg/kgFDWU** -,-,1931
subcutaneous/cat lowest published lethal dose: 1100 µg/kgHBAMAK 4,1340,1935
subcutaneous/Dog lowest published lethal dose: 1700 µg/kgHBAMAK 4,1340,1935
subcutaneous/domestic bird lowest published lethal dose: 100 µg/kgHBAMAK 4,1340,1935
subcutaneous/frog lowest published lethal dose: 60 mg/kgHBAMAK 4,1340,1935
subcutaneous/guinea pig lowest published lethal dose: 100 µg/kgHBAMAK 4,1340,1935
subcutaneous/human lowest published lethal dose: 1 mg/kgSCJUAD 3(4),33,1967
subcutaneous/mouse lowest published lethal dose: 3 mg/kgHBAMAK 4,1340,1935
subcutaneous/pigeon lowest published lethal dose: 2150 µg/kgFDWU** -,-,1931
subcutaneous/rabbit lethal dose (50 percent kill): 2500 µg/kgBJPCAL 23,455,1964
subcutaneous/wild bird lowest published lethal dose: 100 µg/kgFDWU** -,-,1931
unreported route/man lowest published lethal dose: 1471 µg/kg85DCAI 2,73,1970

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
oral/domestic animal lowest published toxic dose: 75 mg/kg/30D- continuousBrain and Coverings: Other degenerative changes

Endocrine: Other changes

Nutritional and Gross Metabolic: Changes in: Cl
JAPTO* 28,356,2008
oral/domestic animal lowest published toxic dose: 10 mg/kg/4D- continuousBehavioral: Alteration of classical conditioningJAPTO* 28,356,2008
oral/domestic animal lowest published toxic dose: 15 mg/kg/6D- continuousBehavioral: Convulsions or effect on seizure thresholdJAPTO* 28,356,2008

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-ceiling concentration 4.7 ppm (skin)DTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWEVHPAZ 11,163,1975
TOXICOLOGY REVIEWFNSCA6 2,67,1973
TOXICOLOGY REVIEWJOCMA7 1,281,1959
TOXICOLOGY REVIEWTOLED5 134,3,2002
TOXICOLOGY REVIEWCPEMM* 3,239,2002
TOXICOLOGY REVIEWTXCYAC 214,221,2005
TOXICOLOGY REVIEWENTOX* -,639,2005
TOXICOLOGY REVIEWENTOX* -,698,2005
TOXICOLOGY REVIEWREPTED 23,428,2007
TOXICOLOGY REVIEWHUTOX* -,661,1996
TOXICOLOGY REVIEWMUREAV 636,144,2007
TOXICOLOGY REVIEWCCACL* 21,691,2005
TOXICOLOGY REVIEWNEUCL* 15,711,1997
TOXICOLOGY REVIEWPRESR* 7,123,2006
TOXICOLOGY REVIEWNTAPM* -,629,1995
TOXICOLOGY REVIEWMUREAV 717,46,2011

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-ARAB Republic of Egypttime-weighted average 10 ppm (10 mg/m3), JAN1993
Occupational Exposure Limit-AUSTRALIAceiling concentration 10 ppm (11 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRALIAtime-weighted average 5 mg(CN)/m3, JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 10 ppm (11 mg/m3);KZW 40 ppm (44 mg/m3), skin, 2007
Occupational Exposure Limit-BELGIUMshort term exposure limit 4.7 ppm (5 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 5 ppm (5 mg/m3), skin, MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 1 mg/m3, short term exposure limit 5 mg/m3, skin, NOV2011
Occupational Exposure Limit-FRANCEVME 2 ppm (2 mg/m3), VLE 10 ppm (10 mg/m3), FEB2006
Occupational Exposure Limit-GERMANYMAK 1.9 ppm (2.1 mg/m3), 2011
Occupational Exposure Limit-GERMANYMAK 2 mg(CN)/m3, inhal, 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 11 mg/m3, short term exposure limit 44 mg/m3, Skin, SEP2000
Occupational Exposure Limit-HUNGARYtime-weighted average 5 mg(CN)/m3, short term exposure limit 20 mg(CN)/m3, Skin, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 5 ppm (5 mg/m3), skin, NOV2011
Occupational Exposure Limit-JAPANOccupational Exposure Limit 5 ppm (5.5 mg/m3), skin, MAY2012
Occupational Exposure Limit-KOREAceiling concentration 10 ppm (11 mg/m3), skin, 2006
Occupational Exposure Limit-MEXICOpeak 9.4 ppm (10 mg/m3), 2004
Occupational Exposure Limit-MEXICOtime-weighted average 5 mg(CN)/m3, 2004
Occupational Exposure Limit-NEW ZEALANDceiling concentration 10 ppm (11 mg/m3), skin, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 5 ppm (5 mg/m3), JAN1999
Occupational Exposure Limit-PERUshort term exposure limit 4.7 ppm (5 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 0.3 mg/m3, CEILING 10 mg/m3, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 0.3 mg/m3, Skin, JUN2003
Occupational Exposure Limit-SWITZERLANDMAK-week 1.9 ppm (2.1 mg/m3), KZG-week 3.8 ppm (4.2 mg/m3), skin, JAN2011
Occupational Exposure Limit-THAILANDtime-weighted average 10 ppm (11 mg/m3), JAN1993
Occupational Exposure Limit-THE NETHERLANDSMAC-C 11 mg/m3, Skin, 2003
Occupational Exposure Limit-THE PHILIPPINEStime-weighted average 10 ppm (11 mg/m3), Skin, JAN1993
Occupational Exposure Limit-TURKEYtime-weighted average 10 ppm (11 mg/m3), Skin, JAN1993
Occupational Exposure Limit-UNITED KINGDOMshort term exposure limit 10 ppm (11 mg/m3), skin, OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 10 ppm (11 mg/m3) (skin)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 10 ppm (11 mg/m3) (skin)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 10 ppm (11 mg/m3) (skin)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 10 ppm (11 mg/m3) (skin)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO HYDROGEN CYANIDE-airshort term exposure limit 4.7 ppm (Sk)NIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 38530; Number of Industries 13; Total Number of Facilities 91; Number of Occupations 57; Total Number of Employees Exposed 3994; Total Number of Female Employees Exposed 254
National Occupational Hazard Survey 1974Hazard Code 38530; Number of Industries 14; Total Number of Facilities 461; Number of Occupations 17; Total Number of Employees Exposed 2137

Status in Federal Agencies

OrganizationReference
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA Section 8(e) Risk Notification, 8EHQ-0892-9215
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
NIOSH Analytical Method, 1994: Cyanides (aerosol and gas), 7904
NIOSH Analytical Method, 1994: Hydrogen cyanide, 6010
On EPA IRIS database
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