2H-Azepin-2-one, hexahydro-

RTECS #
CM3675000
CAS #
105-60-2
See: NMAM or OSHA Methods
Updated
December 2015
Molecular Weight
113.18
Molecular Formula
C6H11NO
Synonyms
1,6-Hexolactam
1-Aza-2-cycloheptanone
2-Azacycloheptanone
2H-Azepin-7-one, hexahydro-
2-Ketohexamethyleneimine
2-Ketohexamethylenimine
2-Oxohexamethyleneimine
2-Oxohexamethylenimine
2-Perhydroazepinone
6-Aminocaproic acid lactam
6-Aminohexanoic acid cyclic lactam
6-Caprolactam
6-Hexanelactam
A1030
Aminocaproic lactam
Caprolactam
Caprolactam monomer
Caprolactam, fume
Caprolattame (French)
Capron PK4
Cyclohexanone iso-oxime
e-Kaprolaktam (Czech)
epsilon-Caprolactam
epsilon-Caprolactam (ACGIH)
Epsylon kaprolaktam (Polish)
Extrom 6N
Hexahydro-2-azepinone
Hexahydro-2H-azepin-2-one (9CI)
Hexamethylenimine, 2-oxo-
Hexanoic acid, 6-amino-, cyclic lactam
Hexanoic acid, 6-amino-, lactam
Hexanolactam
Hexanone isoxime
Hexanonisoxim (German)
Kapromine
NCI-C50646
omega-Caprolactam
Stilon

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
eye /rabbit 20 mg/24H moderate85JCAE -,883,1986
skin /rabbit 500 mg/24H mild85JCAE -,883,1986

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
body fluid assayovary/rat76 mg/kgMUREAV 143,263,1985
Cytogenetic Analysislymphocyte/human270 mg/LPMRSDJ 5,457,1985
Cytogenetic Analysislung/hamster8 gm/LPMRSDJ 5,427,1985
DNA Damageintraperitoneal/rat580 mg/kgMUREAV 224,379,1989
DNA Damageintraperitoneal/mouse580 mg/kgMUREAV 224,379,1989
DNA inhibitionfibroblast/human1 mmol/LNEOLA4 33,699,1986
gene conversion and mitotic recombination/Saccharomyes cerevisiae400 mg/LPMRSDJ 5,271,1985
micronucleus testmultiple/non-mammalian species100 ppmMUTAEX 4,17,1989
morphological transformembryo/hamster100 mg/LTIVIEQ 2,103,1988
morphological transformembryo/mouse2500 mg/LPMRSDJ 5,639,1985
mutation in microorganisms/Saccharomyes cerevisiae100 mg/L (+/-enzymatic activation step)PMRSDJ 5,271,1985
phage inhibition capacity/Escherichia coli1950 µg/wellMUREAV 260,349,1991
sex chromosome loss and nondisjunctionoral/Drosophila melanogaster5 mmol/LMUREAV 224,339,1989
sex chromosome loss and nondisjunctionlymphocyte/human25 mmol/LMUREAV 224,333,1989
sister chromatid exchangeovary/hamster125 mmol/LMUREAV 224,333,1989
specific locus testoral/Drosophila melanogaster5 mmol/LPMRSDJ 5,313,1985
specific locus testintraperitoneal/mouse500 mg/kgMUREAV 224,369,1989
sperm morphologyinhalation/rat125 mg/m3/10WGTPZAB 19(10),40,1975

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
inhalation/rat 125 mg/m3/24H (76D male)Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)GTPZAB 19(10),40,1975
inhalation/rat 473 mg/m3/4H (1-5D pregnant)Reproductive: Effects on fertility: Pre- implantation mortality (e.g., reduction in number of implants per female; total number of implants per corpora lutea)

Reproductive: Effects on embryo or fetus: Fetal death
GISAAA 34(7),25,1969
inhalation/rat 139 mg/m3/4H (6-12D pregnant)Reproductive: Effects on fertility: Pre- implantation mortality (e.g., reduction in number of implants per female; total number of implants per corpora lutea)GISAAA 34(7),25,1969
inhalation/rat 473 mg/m3/4H (60D prior to copulation)Reproductive: Maternal effects: Menstrual cycle changes or disordersGTPZAB 13(10),22,1969
oral/rabbit 3450 mg/kg (6-28D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)JJATDK 7,317,1987
oral/rabbit 2500 mg/kg (6-15D pregnant)Reproductive: Effects on newborn: Growth statistics (e.g., reduced weight gain)NTIS** OTS0537802
oral/rat 10 gm/kg (6-15D pregnant)Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)JJATDK 7,317,1987
oral/rat 10 gm/kg (6-15D pregnant)Reproductive: Effects on newborn: Growth statistics (e.g., reduced weight gain)NTIS** OTS0537802
oral/rat 10 gm/kg (6-15D pregnant)Reproductive: Other effects on female

Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)
NTIS** OTS0557708

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/human lowest published toxic concentration: 100 ppmLung, Thorax, or Respiration: CoughAIHAAP 34,384,1973
inhalation/mouse lethal concentration (50 percent kill): 450 mg/m3Behavioral: Muscle contraction or spasticityGTPZAB 10(10),54,1966
inhalation/mouse lethal concentration (50 percent kill): 450 mg/m3TOVEFN (1),20,2001
inhalation/rat lethal concentration (50 percent kill): 300 mg/m3TOVEFN (1),20,2001
inhalation/rat lethal concentration (50 percent kill): 300 mg/m3/2H85GMAT -,32,1982
intraperitoneal/mouse lethal dose (50 percent kill): 650 mg/kgBehavioral: Convulsions or effect on seizure threshold

Behavioral: Antipsychotic

Behavioral: Analgesia
JPMSAE 60,1058,1971
intraperitoneal/rat lowest published lethal dose: 800 mg/kgBehavioral: Convulsions or effect on seizure threshold

Gastrointestinal: Changes in structure or function of salivary glands

Nutritional and Gross Metabolic: Body temperature decrease
BJIMAG 11,1,1954
intravenous/mouse lethal dose (50 percent kill): 480 mg/kgIMEMDT 39,247,1986
intravenous/rabbit Lethal dose: >300 mg/kgBehavioral: Convulsions or effect on seizure threshold

Gastrointestinal: Changes in structure or function of salivary glands

Nutritional and Gross Metabolic: Body temperature decrease
BJIMAG 11,1,1954
oral/mouse lethal dose (50 percent kill): 930 mg/kgBehavioral: Muscle contraction or spasticity

Lung, Thorax, or Respiration: Dyspnea
GTPZAB 10(10),54,1966
oral/rat lethal dose (50 percent kill): 1210 mg/kgEye: Chromodacryorrhea

Behavioral: Convulsions or effect on seizure threshold

Nutritional and Gross Metabolic: Body temperature decrease
NTPTR* NTP-TR-214,1982
skin/rabbit lethal dose (50 percent kill): 1410 µL/kgAIHAAP 30,470,1969
skin/rat lethal dose (50 percent kill): >2 gm/kgNTIS** OTS0557720
subcutaneous/frog lowest published lethal dose: 2800 mg/kgAutonomic Nervous System: Other (direct) parasympathomimetic

Behavioral: Somnolence (general depressed activity)

Behavioral: Convulsions or effect on seizure threshold
AEXPBL 50,199,1903
subcutaneous/guinea pig lowest published lethal dose: 950 mg/kgMELAAD 43,124,1952
subcutaneous/mouse lethal dose (50 percent kill): 750 mg/kgIMEMDT 39,247,1986
unreported route/mouse lethal dose (50 percent kill): 930 mg/kgBehavioral: Convulsions or effect on seizure threshold

Kidney, Ureter, and Bladder: Urine volume increased
GISAAA 55(10),33,1990
unreported route/rabbit lethal dose (50 percent kill): 1 gm/kgBehavioral: Convulsions or effect on seizure threshold

Kidney, Ureter, and Bladder: Urine volume increased
GISAAA 55(10),33,1990
unreported route/rat lethal dose (50 percent kill): 580 mg/kgBehavioral: Convulsions or effect on seizure threshold

Kidney, Ureter, and Bladder: Urine volume increased
GISAAA 55(10),33,1990

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/rat lowest published toxic concentration: 243 mg/m3/6H/13W- intermittentOlfaction: Other olfaction effects

Lung, Thorax, or Respiration: Dyspnea

Lung, Thorax, or Respiration: Other changes
TOSCF2 44,197,1998
inhalation/rat lowest published toxic concentration: 5960 mg/kg/82D- continuousKidney, Ureter, and Bladder: Other changes in urine composition

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
GISAAA 33(1),22,1968
intraperitoneal/rat lowest published toxic dose: 9100 mg/kg/26W- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Blood: Changes in other cell count (unspecified)

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
MEPAAX 18,357,1967
oral/rat lowest published toxic dose: 42 gm/kg/8W- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gainARZNAD 9,9,1959
oral/rat lowest published toxic dose: 6750 mg/kg/2W- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainNTIS** OTS0555505

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 5 mg/m3 (inhal, vapor)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not suspected as a human carcinogenDTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Animal NO EVIDENCEIMEMDT 39,247,1986
International Agency for Research on Cancer (IARC)Cancer Review:Animal No EvidenceIMEMDT 71,383,1999
International Agency for Research on Cancer (IARC)Cancer Review:Human No Adequate DataIMEMDT 39,247,1986
International Agency for Research on Cancer (IARC)Cancer Review:Human No Adequate DataIMEMDT 71,383,1999
International Agency for Research on Cancer (IARC)Cancer Review:Group 4IMEMDT 71,383,1999
TOXICOLOGY REVIEWFCTOD7 47,1287,2009
TOXICOLOGY REVIEWTOLED5 199,203,2010
TOXICOLOGY REVIEWFCTOD7 55,596,2013

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 1 mg/m3, short term exposure limit 3 mg/m3 (dust and vapor), JUL2008
Occupational Exposure Limit-AUSTRALIAtime-weighted average 1 mg/m3, short term exposure limit 3 mg/m3 (dust), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 5 mg/m3;KZW 40 mg/m3, inhal, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 1 mg/m3, short term exposure limit 3 mg/m3 (dust), MAR2002
Occupational Exposure Limit-BELGIUMtime-weighted average 2.2 ppm (10 mg/m3), (vapor), MAR2002
Occupational Exposure Limit-BELGIUMshort term exposure limit 8.7 ppm (40 mg/m3) (vapor), MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 1 mg/m3 (dust), MAY2011
Occupational Exposure Limit-DENMARKtime-weighted average 2 ppm (10 mg/m3) (vapor), MAY2011
Occupational Exposure Limit-ECtime-weighted average 10 mg/m3;short term exposure limit 40 mg/m3 (dust, vapor), JUN2000
Occupational Exposure Limit-FINLANDtime-weighted average 10 mg/m3, short term exposure limit 40 mg/m3, NOV2011
Occupational Exposure Limit-FRANCEVME 10 mg/m3 (dust, vapor), VLE 40 mg/m3 (dust, vapor), FEB2006
Occupational Exposure Limit-GERMANYMAK 5 mg/m3 (dust, vapor, inhal.), 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 10 mg/m3, short term exposure limit 40 mg/m3, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 1 mg/m3, dust, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 1 mg/m3, short term exposure limit 3 mg/m3, 2006
Occupational Exposure Limit-KOREAtime-weighted average 5 ppm (20 mg/m3), short term exposure limit 10 ppm (40 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 1 mg/m3 (dust), 2004
Occupational Exposure Limit-MEXICOtime-weighted average 5 ppm (20 mg/m3);short term exposure limit 3 mg/m3 (vapor), 2004
Occupational Exposure Limit-MEXICOshort term exposure limit 10 ppm (40 mg/m3) (vapor), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 5 ppm (23 mg/m3); short term exposure limit 10 ppm (46 mg/m3) (vapor), JAN2002
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 1 mg/m3; short term exposure limit 3 mg/m3 (dust), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 5 ppm (25 mg/m3), moist, JAN1999
Occupational Exposure Limit-PERUtime-weighted average 5 mg/m3, JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 10 mg/m3 (dust), JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 10 mg/m3, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 5 mg/m3;short term exposure limit 10 mg/m3, (dust, vapour), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 5 mg/m3, inhal, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 1 mg/m3 (dust), 2003
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 20 mg/m3 (fume), 2003
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 1 mg/m3; short term exposure limit 3 mg/m3 (dust), OCT2007
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 10 mg/m3; short term exposure limit 20 mg/m3 (dust, vapor), OCT2007

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO CAPROLACTAM, dust-air10H time-weighted average 1 mg/m3;short term exposure limit 3 mg/m3NIOSH* DHHS #95-121,1995
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO CAPROLACTAM, vapor-air10H time-weighted average 0.22 ppm;short term exposure limit 0.66 ppmNIOSH* DHHS #95-121,1995
National Occupational Exposure Survey 1983Hazard Code 83732; Number of Industries 12; Total Number of Facilities 812; Number of Occupations 19; Total Number of Employees Exposed 25091; Total Number of Female Employees Exposed 8291
National Occupational Hazard Survey 1974Hazard Code 83732; Number of Industries 14; Total Number of Facilities 955; Number of Occupations 14; Total Number of Employees Exposed 6208

Status in Federal Agencies

OrganizationReference
EPA GENETOX PROGRAM 1988, Negative: Carcinogenicity-mouse/rat
EPA GENETOX PROGRAM 1988, Negative: CHO gene mutation
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
NCI Carcinogenesis Studies (feed);no evidence:mouse,rat
On EPA IRIS database
Page last reviewed: November 16, 2018