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Isocyanic acid, methylene(3,5,5-trimethyl-3,1-cyclohexylene) ester

RTECS #
NQ9370000
CAS #
4098-71-9
See: NMAM or OSHA Methods
Updated
June 2018
Molecular Weight
222.32
Molecular Formula
C12H18N2O2
Synonyms
3-Isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate
Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl- (9CI)
IPDI
Isophorone diamine diisocyanate
Isophorone diisocyanate
Isophorone diisocyanate (ACGIH)

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
skin /mouse 1%/5D-continuousNTPTR* IMM-90001.

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
oral/mouse 415 mg/kg (8-12D pregnant)Reproductive: Effects on newborn: Viability index (e.g., # alive at day 4 per # born alive)WDZAEK 5,178,1991

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, lung Inhibitor Concentration (50 percent kill): 103 gm/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 27,174,2013
In Vitro/Human, lung Inhibitor Concentration (50 percent kill): 95 gm/L/24HIn Vitro Toxicity Studies: Cell membrane integrity: Cytoplasmic enzymes leakage (lactate dehydrogenase, ATP enzymes etc.)TIVIEQ 27,174,2013
In Vitro/Human, lung Inhibitor Concentration (50 percent kill): 42 gm/L/24HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 27,174,2013
In Vitro/Human, lung Inhibitor Concentration (50 percent kill): 26 gm/L/24HIn Vitro Toxicity Studies: Other assaysTIVIEQ 27,174,2013
In Vitro/Human, lung tumor Inhibitor Concentration (50 percent kill): 7.6 gm/L/24HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 27,174,2013
In Vitro/Mouse, fibroblast Inhibitor Concentration (50 percent kill): 1.2 gm/L/24HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 27,174,2013
In Vitro/Rat, lung Inhibitor Concentration (50 percent kill): 1778.3 µmol/L/1HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 32,347,2016
In Vitro/Rat, lung Inhibitor Concentration (50 percent kill): 5128.6 µmol/L/1HIn Vitro Toxicity Studies: Cell membrane integrity: Cytoplasmic enzymes leakage (lactate dehydrogenase, ATP enzymes etc.)TIVIEQ 32,347,2016
In Vitro/Rat, lung Inhibitor Concentration (50 percent kill): 851.1 µmol/L/1HIn Vitro Toxicity Studies: Cell protein synthesisTIVIEQ 32,347,2016
In Vitro/Rat, lung Inhibitor Concentration (50 percent kill): 2511.9 µmol/L/1HBiochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammationTIVIEQ 32,347,2016
inhalation/guinea pig lethal concentration (50 percent kill): 118 mg/m3/1HBehavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Dyspnea

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
NTIS** OTS0543418
inhalation/rat lowest published toxic concentration: 7.5 mg/m3/6HLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Changes in lung weight
JAPTO* 24,231,2004
inhalation/rat lowest published toxic concentration: 2.1 mg/m3/6HLung, Thorax, or Respiration: Other changesJAPTO* 24,231,2004
inhalation/rat lowest published toxic concentration: 7.5 mg/m3/6HNutritional and Gross Metabolic: Body temperature decreaseJAPTO* 24,231,2004
inhalation/rat lethal concentration (50 percent kill): 123 mg/m3/4H85INA8 5,334(86),1986
oral/cat lethal dose (50 percent kill): 1 mL/kgNTIS** OTS0528418
oral/mouse lowest published lethal dose: 2500 µL/kgNTIS** OTS0528418
oral/rat lethal dose (50 percent kill): 4825 mg/kgNTIS** OTS0530238
skin/rat lowest published lethal dose: 1 mL/kgNTIS** OTS0528418

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/mouse lowest published toxic concentration: 7.5 mg/m3/3D- intermittentImmunological Including Allergic: Increased immune response

Biochemical: Metabolism (intermediary): Other proteins

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TXCYAC 261,103,2009
inhalation/rat lowest published toxic concentration: 1370 µg/m3/4H/4W- intermittentLung, Thorax, or Respiration: Changes in lung weight

Liver: Changes in liver weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
NTIS** OTS0528418
skin/mouse lowest published toxic dose: 220 mg/kg/12D- intermittentSkin: After topical application: Cutaneous sensitization (experimental)

Biochemical: Metabolism (intermediary): Other proteins

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TXCYAC 207,487,2005
skin/mouse lowest published toxic dose: 480 mg/kg/28D- intermittentImmunological Including Allergic: Increase in humoral responseTOSCF2 94,108,2006
skin/mouse lowest published toxic dose: 1 pph/3D- intermittentImmunological Including Allergic: Increased immune response

Biochemical: Metabolism (intermediary): Other proteins

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TXCYAC 261,103,2009

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 0.005 ppmDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWTOLED5 140-141,213,2003

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 0.02 mg(NCO)/m3, short term exposure limit 0.07 mg(NCO)/m3, JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 0.01 ppm (0.09 mg/m3);KZW 0.02 ppm (0.18 mg/m3), sen, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 0.005 ppm (0.046 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 0.005 ppm (0.045 mg/m3), MAY2011
Occupational Exposure Limit-FRANCEVME 0.01 ppm (0.09 mg/m3), VLE 0.02 ppm (0.18 mg/m3), FEB2006
Occupational Exposure Limit-GERMANYMAK 0.005 ppm (0.046 mg/m3), 2011
Occupational Exposure Limit-ICELANDtime-weighted average 0.005 ppm (0.05 mg/m3), short term exposure limit 0.01 ppm (0.09 mg/m3), skin, sen, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 0.005 ppm (0.045 mg/m3), skin, 2006
Occupational Exposure Limit-MEXICOtime-weighted average 0.01 ppm (0.09 mg/m3), 2004
Occupational Exposure Limit-NORWAYtime-weighted average 0.005 ppm (0.045 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 0,005 ppm (0,045 mg/m3), JUL2005
Occupational Exposure Limit-SWEDENtime-weighted average 0.002 ppm (0.018 mg/m3), ceiling concentration 0.005 ppm (0.046 mg/m3), Sen, JUN2005
Occupational Exposure Limit-SWITZERLANDceiling concentration 0.02 mg(NCO)/m3, skin, sen, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 0.05 mg/m3, 2003

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO IPDI-air10H time-weighted average 0.005 ppm (Sk);short term exposure limit 0.02 ppm (Sk)NIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 83571; Number of Industries 15; Total Number of Facilities 1186; Number of Occupations 16; Total Number of Employees Exposed 7245; Total Number of Female Employees Exposed 682
National Occupational Hazard Survey 1974Hazard Code 83571; Number of Industries 4; Total Number of Facilities 111; Number of Occupations 19; Total Number of Employees Exposed 3441

Status in Federal Agencies

OrganizationReference
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
Page last reviewed: November 16, 2018