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Naphthalene

RTECS #
QJ0525000
CAS #
91-20-3
See: NMAM or OSHA Methods
Updated
December 2018
Molecular Weight
128.18
Molecular Formula
C10H8
Synonyms
Albocarbon
Camphor tar
Mighty 150
Mighty RD1
Moth balls
Moth flakes
Naftalen (Polish)
Naphthalene (ACGIH:OSHA)
Naphthalin
Naphthaline
Naphthene
NCI-C52904
RCRA waste number U165
Tar camphor
White tar

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
skin /rabbit 495 mg open irritation test mildUCDS** 1/11/1968
skin /rabbit 0.05 mL/24H severeETOPFR 16,153,2004

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysisovary/hamster30 mg/LNTPTR* NTP-TR-410,1992
Cytogenetic Analysislung/hamster234 µmol/LMUREAV 608,28,2006
Cytogenetic Analysisother cell types/hamster234 µmol/LMUREAV 608,28,2006
micronucleus testliver/human125 µmol/L/24HMUTAEX 30,593,2015
micronucleus testlymphocyte/human30 mg/LMUREAV 393,23,1997
morphological transformfibroblast/mouse0.1 mg/L/21D (-enzymatic activation step)EMMUEG 37,231,2001
sister chromatid exchangeovary/hamster15 mg/LNTPTR* NTP-TR-410,1992
specific locus testoral/Drosophila melanogaster5 mmol/LMUREAV 341,235,1995
specific locus testinhalation/rat30 ppm/13W- intermittentMUREAV 721,199,2011

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
intraperitoneal/rat 5925 mg/kg (1-15D pregnant)Reproductive: Specific developmental abnormalities: Musculoskeletal system

Reproductive: Specific developmental abnormalities: Cardiovascular (circulatory) system
TXAPA9 48,A35,1979
oral/mouse 2400 mg/kg (7-14D pregnant)Reproductive: Effects on newborn: Live birth index (Litter size (e.g., # fetuses per litter; measured after birth)

Reproductive: Effects on newborn: Viability index (e.g., # alive at day 4 per # born alive)
JTEHD6 15,25,1985
oral/rat 4500 mg/kg (6-15D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)

Reproductive: Other developmental abnormalities
NTIS** PB92-135623

Tumorigenic Data and References

Route/OrganismDoseEffectReference
inhalation/mouse lowest published toxic concentration: 1854 mg/kg/103W- intermittentTumorigenic: Neoplastic by RTECS criteria

Olfaction: Other olfaction effects

Lung, Thorax, or Respiration: Tumors
NTIS** PB92-224260/AS
inhalation/mouse lowest published toxic concentration: 30 ppm/6H/2Y- intermittentTumorigenic: Neoplastic by RTECS criteria

Lung, Thorax, or Respiration: Tumors
NTPTR* NTP-TR-410,1992
inhalation/mouse lowest published toxic concentration: 4386.2 mg/kg/13W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Lung, Thorax, or Respiration: Tumors
MUREAV 746,135,2012
inhalation/rat lowest published toxic concentration: 1890 mg/kg/105W- intermittentTumorigenic: Carcinogenic by RTECS criteria

Olfaction: Tumors
NTIS** PB2001-103699
inhalation/rat lowest published toxic concentration: 1575 mg/kg/105W- intermittentTumorigenic: Carcinogenic by RTECS criteria

Olfaction: Tumors
NTIS** PB2001-103699
inhalation/rat lowest published toxic concentration: 30 ppm/6H/105W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Olfaction: Tumors
TOPADD 31,655,2003
inhalation/rat lowest published toxic concentration: 10 ppm/6H/105W- intermittentTumorigenic: Neoplastic by RTECS criteria

Olfaction: Tumors
TOPADD 31,655,2003
inhalation/rat lowest published toxic concentration: 60 ppm/6H/105W- intermittentTumorigenic: Carcinogenic by RTECS criteria

Olfaction: Tumors
TOPADD 31,655,2003
inhalation/rat lowest published toxic concentration: 10 ppm/6H/105W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Olfaction: Tumors
TOPADD 31,655,2003
intraperitoneal/mouse lowest published toxic dose: 300 mg/kgTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Lung, Thorax, or Respiration: Tumors

Tumorigenic: Increased incidence of tumors in susceptible strains
TOLED5 181,67,2008
subcutaneous/rat lowest published toxic dose: 3500 mg/kg/12W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Blood: Lymphoma including Hodgkin's disease

Reproductive: Tumorigenic effects: Uterine tumors
APAVAY 329,141,1956

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, embryonic cells Inhibitor Concentration Low: 40 µg/L/72HIn Vitro Toxicity Studies: Other assaysTOLED5 280,10,2017
In Vitro/Human, embryonic cells Inhibitor Concentration Low: 40 µg/L/24HIn Vitro Toxicity Studies: Other assaysTOLED5 280,10,2017
In Vitro/Human, embryonic cells Inhibitor Concentration Low: 40 µg/L/72HIn Vitro Toxicity Studies: Apoptosis in vitro

In Vitro Toxicity Studies: Other assays
TOLED5 280,10,2017
In Vitro/Human, liver tumor Inhibitor Concentration (20 percent kill): 1772.23 µmol/L/48HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TOLED5 212,18,2012
In Vitro/Human, lung tumor Inhibitor Concentration Low: 0.2 µmol/L/14HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 35,1,2016
inhalation/human lowest published toxic concentration: 250 mg/m3Eye: Lacrimation

Behavioral: Headache
VCVGH* -,221,1990
inhalation/mammal (species unspecified) lowest published toxic concentration: 2 ppmLung, Thorax, or Respiration: Other changesTOXID9 -,55,2009
inhalation/mouse lowest published toxic concentration: 5 ppm/4HLung, Thorax, or Respiration: Other changesTOLED5 246,35,2016
inhalation/rat lowest published toxic concentration: 0.1 ppm/6HOlfaction: Other olfaction effectsTOXID9 -,105,2008
inhalation/rat lowest published toxic concentration: 10 ppm/6HOlfaction: Other olfaction effects

Lung, Thorax, or Respiration: Other changes
TOXID9 -,105,2008
inhalation/rat lowest published toxic concentration: 3.4 ppm/4HOlfaction: Other olfaction effectsJPETAB 314,103,2005
intraperitoneal/mammal (species unspecified) lowest published toxic dose: 150 mg/kgLung, Thorax, or Respiration: Other changesTOXID9 -,55,2009
intraperitoneal/mouse lowest published toxic dose: 50 mg/kgLung, Thorax, or Respiration: Structural or functional change in trachea or bronchiTOXID9 -,189,2009
intraperitoneal/mouse lowest published toxic dose: 400 mg/kgLung, Thorax, or Respiration: Other changes

Liver: Other changes

Kidney, Ureter, and Bladder: Other changes
VCVGH* -,220,1990
intraperitoneal/mouse lowest published toxic dose: 200 mg/kgLung, Thorax, or Respiration: Structural or functional change in trachea or bronchi

Biochemical: Metabolism (intermediary): Other proteins
TXAPA9 192,107,2003
intraperitoneal/mouse lethal dose (50 percent kill): 150 mg/kgNTIS** AD691-490
intraperitoneal/rat lowest published toxic dose: 100 mg/kgOlfaction: Other olfaction effectsJPETAB 314,103,2005
intravenous/mouse lethal dose (50 percent kill): 100 mg/kgCSLNX* NX#00203
oral/cat lowest published lethal dose: 1 gm/kgHBAMAK 4,1289,1935
oral/child lowest published lethal dose: 100 mg/kg28ZRAQ -,228,1960
oral/Dog lowest published lethal dose: 400 mg/kgHBAMAK 4,1289,1935
oral/guinea pig lethal dose (50 percent kill): 1200 mg/kgBehavioral: Somnolence (general depressed activity)

Behavioral: Change in motor activity (specific assay)
GISAAA 47(11),78,1982
oral/mouse lowest published toxic dose: 158 mg/kgBrain and Coverings: Other degenerative changes

Liver: Other changes

Biochemical: Metabolism (intermediary): Lipids including transport
TXCYAC 175,73,2002
oral/mouse lethal dose (50 percent kill): 316 mg/kgWDZAEK 4,243,1990
oral/rabbit lowest published lethal dose: 3 gm/kgHBAMAK 4,1289,1935
oral/rat lethal dose (50 percent kill): 490 mg/kg85GMAT -,89,1982
skin/rabbit lethal dose (50 percent kill): >20 gm/kgNTIS** AD-A062-138
skin/rabbit lowest published toxic dose: 0.03 mL/kg/24HVascular: Measurement of regional blood flowETOPFR 16,153,2004
skin/rat lethal dose (50 percent kill): >2500 mg/kgTXAPA9 14,515,1969
subcutaneous/mouse lethal dose (50 percent kill): 969 mg/kgBehavioral: TremorTOIZAG 20,772,1973
unreported route/guinea pig lethal dose (50 percent kill): 1200 mg/kgBehavioral: Somnolence (general depressed activity)VCVGH* -,220,1990
unreported route/human lowest published lethal dose: 29 mg/kgYKYUA6 31,1499,1980
unreported route/man lowest published lethal dose: 74 mg/kg85DCAI 2,73,1970
unreported route/mouse lethal dose (50 percent kill): 580 mg/kgBehavioral: Somnolence (general depressed activity)VCVGH* -,220,1990
unreported route/rat lethal dose (50 percent kill): 1250 mg/kgBehavioral: Somnolence (general depressed activity)VCVGH* -,220,1990

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/mouse lowest published toxic concentration: 536.9 mg/kg/13W- intermittentLung, Thorax, or Respiration: Other changesMUREAV 746,135,2012
inhalation/rat lowest published toxic concentration: 10 ppm/6H/105W- intermittentOlfaction: Other olfaction effects

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TOPADD 31,655,2003
inhalation/rat lowest published toxic concentration: 10 ppm/6H/105W- intermittentOlfaction: Other olfaction effects

Olfaction: Tumors

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TOPADD 31,655,2003
inhalation/rat lowest published toxic concentration: 10 ppm/5D- intermittentOlfaction: Other olfaction effectsTOXID9 -,306,2009
intraperitoneal/rabbit lowest published toxic dose: 2 gm/kg/2D- intermittentEye: Other eye effectsLETRET 6,203,1989
intraperitoneal/rat lowest published toxic dose: 256 mg/kg/7D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainARTODN 77,183,2003
multiple/rat lowest published toxic dose: 256.36 mg/kg/3D- intermittentLung, Thorax, or Respiration: Other changes

Liver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects
ARTODN 81,169,2007
oral/mouse lowest published toxic dose: 3738 mg/kg/14D- continuousBlood: Changes in spleen

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
FAATDF 4,406,1984
oral/mouse lowest published toxic dose: 11970 mg/kg/90D- continuousBlood: Changes in spleenFAATDF 4,406,1984
oral/rabbit lowest published toxic dose: 10 gm/kg/10D- intermittentEye: Other eye effects

Gastrointestinal: Other changes

Blood: Hemorrhage
BIJOAK 102,842,1967
oral/rabbit lowest published toxic dose: 2100 mg/kg/14D- intermittentRelated to Chronic Data: Death in the "MULTIPLE DOSE" data type fieldNTIS** #PB92-219831
oral/rat lowest published toxic dose: 500 mg/kg/10D- intermittentBehavioral: Sleep

Lung, Thorax, or Respiration: Dyspnea
NTIS** #PB92-135623
oral/rat lowest published toxic dose: 1500 mg/kg/10D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainNTIS** #PB92-135623
oral/rat lowest published toxic dose: 600 mg/kg/4D- intermittentBehavioral: Food intake (animal)

Behavioral: Fluid intake
NTIS** #PB92-135623
oral/rat lowest published toxic dose: 4500 mg/kg/10D- intermittentBrain and Coverings: Other degenerative changesNTIS** #PB92-135623
oral/rat lowest published toxic dose: 20 gm/kg/11W- intermittentEye: Other eye effectsTOLED5 115,195,2000
oral/rat lowest published toxic dose: 10 gm/kg/10D- intermittentLiver: Other changes

Liver: Changes in liver weight

Biochemical: Metabolism (intermediary): Lipids including transport
TOLED5 8,311,1981
oral/rat lowest published toxic dose: 12450 mg/kg/9W- intermittentLiver: Other changes

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other oxidoreductases
ARTODN 61,480,1988

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 10 ppm;short term exposure limit 15 ppm (skin)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Animal Sufficient EvidenceIMEMDT 82,367,2002
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 82,367,2002
International Agency for Research on Cancer (IARC)Cancer Review:Group 2BIMEMDT 82,367,2002
TOXICOLOGY REVIEWCRTXB2 1(1),93,1971
TOXICOLOGY REVIEWJOPDAB 59,1,1961
TOXICOLOGY REVIEWTXCYAC 180,1,2002
TOXICOLOGY REVIEWMUREAV 540,89,2003
TOXICOLOGY REVIEWMUREAV 558,155,2004
TOXICOLOGY REVIEWTXCYAC 180,97,2002
TOXICOLOGY REVIEWMUREAV 558,7,2004
TOXICOLOGY REVIEWTOLED5 140-141,353,2003
TOXICOLOGY REVIEWMUREAV 543,201,2003
TOXICOLOGY REVIEWMUREAV 567,401,2004
TOXICOLOGY REVIEWMUREAV 566,209,2004
TOXICOLOGY REVIEWENTOX* -,185,2005
TOXICOLOGY REVIEWMUREAV 584,1,2005
TOXICOLOGY REVIEWBCLPT* 96,131,2005
TOXICOLOGY REVIEWHETOEA 25,413,2006
TOXICOLOGY REVIEWMUREAV 636,95,2007
TOXICOLOGY REVIEWJTEHD6 6,161,2003
TOXICOLOGY REVIEWREPTED 25,192,2008
TOXICOLOGY REVIEWMUREAV 659,248,2008
TOXICOLOGY REVIEWHUTOX* -,247,1996
TOXICOLOGY REVIEWMUREAV 681,93,2009
TOXICOLOGY REVIEWMUREAV 636,4,2007
TOXICOLOGY REVIEWRTOPDW 51,S6,2008
TOXICOLOGY REVIEWAIRMJ* 20,8,2001
TOXICOLOGY REVIEWIMEMDT 82,367,
TOXICOLOGY REVIEWMUREAV 705,184,2010
TOXICOLOGY REVIEWMUTAEX 26,231,2011
TOXICOLOGY REVIEWMUREAV 722,147,2011
TOXICOLOGY REVIEWMUREAV 763,36,2014
TOXICOLOGY REVIEWTOLED5 205,279,2011
TOXICOLOGY REVIEWMUREAV 762,76,2014
TOXICOLOGY REVIEWMUREAV 769,34,2014
TOXICOLOGY REVIEWTXAPA9 266,67,2013
TOXICOLOGY REVIEWFCTOD7 86,144,2015
TOXICOLOGY REVIEWFCTOD7 86,309,2015
TOXICOLOGY REVIEWMUREAV 802,1,2016
TOXICOLOGY REVIEWREPTED 73,61,2017
TOXICOLOGY REVIEWRTOPDW 55,205,2009

Standards and Regulations

OrganizationStandardReference
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1988 PESTICIDE SUBJECT TO REGISTRATION OR RE-REGISTRATIONFEREAC 54,7740,1989
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1998 STATUS OF PESTICIDESSupportedRBREV* -,135,1998
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 10 ppm (50 mg/m3)DTLVS* 3,177,1971
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 (50 mg/m3), JAN1993
Occupational Exposure Limit-AUSTRALIAtime-weighted average 10 ppm (52 mg/m3), short term exposure limit 15 ppm (79 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 10 ppm (50 mg/m3), skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 10 ppm (53 mg/m3), MAR2002
Occupational Exposure Limit-BELGIUMshort term exposure limit 15 ppm (80 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 10 ppm (50 mg/m3), carc, MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 1 ppm (5 mg/m3), short term exposure limit 2 ppm (10 mg/m3), NOV2011
Occupational Exposure Limit-FRANCEVME 10 ppm (50 mg/m3), C3 Carcinogen, FEB2006
Occupational Exposure Limit-HUNGARYtime-weighted average 50 mg/m3, Skin, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 10 ppm (50 mg/m3), NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 10 ppm (50 mg/m3), short term exposure limit 15 ppm (75 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 10 ppm (50 mg/m3);short term exposure limit 15 ppm (75 mg/m3), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 10 ppm (52 mg/m3); short term exposure limit 15 ppm (79 mg/m3), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 10 ppm (50 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 10 ppm (52 mg/m3); short term exposure limit 15 ppm (79 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 20 mg/m3, MAC(short term exposure limit) 75 mg/m3, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 20 mg/m3, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 10 ppm (50 mg/m3);short term exposure limit 15 ppm (80 mg/m3), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 10 ppm (50 mg/m3), carc 3, skin, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 50 mg/m3, 2003
Occupational Exposure Limit-THE PHILIPPINEStime-weighted average 10 ppm (50 mg/m3), JAN1993
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 10 ppm (50 mg/m3)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 10 ppm (50 mg/m3)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 10 ppm (50 mg/m3)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 10 ppm (50 mg/m3)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO NAPHTHALENE-air10H time-weighted average 10 ppm;short term exposure limit 15 ppmNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 49600; Number of Industries 83; Total Number of Facilities 7209; Number of Occupations 87; Total Number of Employees Exposed 112696; Total Number of Female Employees Exposed 5220
National Occupational Hazard Survey 1974Hazard Code 49600; Number of Industries 71; Total Number of Facilities 4341; Number of Occupations 68; Total Number of Employees Exposed 44297

Status in Federal Agencies

OrganizationReference
ATSDR TOXICOLOGY PROFILE (NTIS** PB/95/264362)
EPA GENETOX PROGRAM 1988, Negative: Cell transform.-mouse embryo
EPA GENETOX PROGRAM 1988, Negative: Cell transform.-RLV F344 rat embryo
EPA GENETOX PROGRAM 1988, Negative: Histidine reversion-Ames test
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 (inhal);clear evidence:rat
NCI Carcinogenesis Studies (inhal);equivocal evidence:mouse
NIOSH Analytical Method, 1994: Hydrocarbons, aromatic, 1501
NIOSH Analytical Method, 1994: Polynuclear aromatic hydrocarbons by HPLC, 5506; by GC, 5515
NTP 14th Report on Carcinogens,2016:Reasonably anticipated to be human carcinogen
NTP Carcinogenesis Studies (inhalation);some evidence:mouse NTPTR* NTP-TR-410,1992
NTP Carcinogenesis studies; test completed (camera copy in progress), October 2000
On EPA IRIS database
OSHA ANALYTICAL METHOD #35
Page last reviewed: November 16, 2018