Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Acetaldehyde 75-07-0 1 2B 0.009 IRIS B2 0.0000022 IRISAcetamide 60-35-5 2 2B 0.00002 CALAcetonitrile 75-05-8 3 0.06 IRIS InI

Acetophenone 98-86-2 4 DAcrolein 107-02-8 6 3 0.00002 IRIS InIAcrylamide 79-06-1 7 2A 0.006 IRIS LH 0.0001 IRIS

Acrylic acid 79-10-7 8 0.001 IRISAcrylonitrile 107-13-1 9 2A 0.002 IRIS B1 0.000068 IRISAllyl chloride 107-05-1 10 3 0.001 IRIS C 0.000006 CALAniline 62-53-3 12 3 0.001 IRIS B2 0.0000016 CALAntimony compounds 7440-36-0 173Antimony pentoxide 1314-60-9 173Antimony potassium tartrate 304-61-0 173Antimony tetroxide 1332-81-6 173Antimony trioxide 1309-64-4 173 2B 0.0002 IRISArsenic compounds 7440-38-2 174 1 0.000015 CAL A 0.0043 IRISArsenic pentoxide 1303-28-2 174Arsine 7784-42-1 174 0.00005 IRISBenzene 71-43-2 15 1 0.03 IRIS CH 0.0000078 IRISBenzidine 92-87-5 16 0.01 P-CAL A 0.067 IRISBenzotrichloride 98-07-7 17 2B B2 0.0037 Conv. OralBenzyl chloride 100-44-7 18 2B B2 0.000049 CALBeryllium compounds 7440-41-7 175 1 0.00002 IRIS LH 0.0024 IRISBeryllium oxide 1304-56-9 175 0.000007 CALBiphenyl 92-52-4 19 DBis(2-ethylhexyl)phthalate 117-81-7 20 2B 0.01 P-CAL B2 0.0000024 CALBis(chloromethyl)ether 542-88-1 21 1 A 0.062 IRISBromoform 75-25-2 22 3 B2 0.0000011 IRIS1,3-Butadiene 106-99-0 23 2A 0.002 IRIS CH 0.00003 IRISCadmium compounds 7440-43-9 176 1 0.00001 D-ATSDR B1 0.0018 IRIS 0.0005 IRI

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Captan 133-06-2 26 3 B2 0.000001 Conv. OralCarbaryl 63-25-2 27Carbon disulfide 75-15-0 28 0.7 IRISCarbon tetrachloride 56-23-5 29 2B 0.1 IRIS LH 0.000006 IRISChloramben 133-90-4 32Chlordane 57-74-9 33 2B 0.0007 IRIS LH 0.0001 IRIS 0.0005 IRIChlorine 7782-50-5 34 0.00015 D-ATSDRChloroacetic acid 79-11-8 352-Chloroacetophenone 532-27-4 36 0.00003 IRISChlorobenzene 108-90-7 37 1 CAL D

Chlorobenzilate 510-15-6 38 B2 0.000078 HEAST

Chloroform 67-66-3 39 2B 0.098 ATSDR LH

Chloroprene 126-99-8 41 0.007 HEAST

Chromium (III) compounds 16065-83-1 177 InIChromium (VI) compounds 18540-29-9 177 1 0.0001 IRIS CH 0.012 IRISChromium (VI) trioxide, chromic acid mist 11115-74-5 177 1 0.000008 IRISCobalt compounds 7440-48-4 178 0.0001 ATSDRCoke Oven Emissions 8007-45-2 179 A 0.00062 IRISm-Cresol 108-39-4 44 Co-Cresol 95-48-7 43 Cp-Cresol 106-44-5 45 CCresols (mixed) 1319-77-3 42 0.6 CAL C

Cumene 98-82-8 46 0.4 IRIS InI

Cyanazine 21725-46-2 180 C 0.00024 Conv. Oral

Cyanide compounds 57-12-5 180 DAcetone cyanohydrin 75-86-5 180 0.01 HEASTCalcium cyanide 592-01-8 180Copper cyanide 544-92-3 180Cyanogen 460-19-5 180Cyanogen bromide 506-68-3 180
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Cyanogen chloride 506-77-4 180Ethylene cyanohydrin 109-78-4 180Hydrogen cyanide 74-90-8 180 0.003 IRISPotassium cyanide 151-50-8 180Potassium silver cyanide 506-61-6 180Silver cyanide 506-64-9 180Sodium cyanide 143-33-9 180Thiocyanic acid, 2-(benzothiazolylthio) methyl est 21564-17-0 180Zinc cyanide 557-21-1 1802,4-D, salts and esters 94-75-7 47DDE 72-55-9 48 B2 0.000097 Conv. Oral 1,2-Dibromo-3-chloropropane 96-12-8 51 0.0002 IRIS B2 0.002 CALDibutylphthalate 84-74-2 52 Dp-Dichlorobenzene 106-46-7 53 2B 0.8 IRIS C 0.000011 CAL3,3'-Dichlorobenzidine 91-94-1 54 2B B2 0.00034 CALDichloroethyl ether 111-44-4 55 B2 0.00033 IRIS1,3-Dichloropropene 542-75-6 56 2B 0.02 IRIS LH 0.000004 IRISDichlorvos 62-73-7 57 2B 0.0005 IRIS B2 0.000083 Conv. OralDiesel engine emissions DIESEL EMIS. 999 0.005 IRIS LH

Diethanolamine 111-42-2 58 0.003 CAL

3,3'-Dimethoxybenzidine 119-90-4 61 2B B2 0.000004 Conv. Oralp-Dimethylaminoazobenzene 60-11-7 62 2B 0.0013 CAL3,3'-Dimethylbenzidine 119-93-7 63 B2 0.0026 Conv. OralDimethyl formamide 68-12-2 65 2B 0.03 IRISN,N-dimethylaniline 121-69-7 59 31,1-Dimethylhydrazine 57-14-7 66 2B B22,4-dinitrophenol 51-28-5 702,4-Dinitrotoluene 121-14-2 71 2B 0.007 P-CAL B2 0.000089 CAL2,4/2,6-Dinitrotoluene (mixture) 25321-14-6 71 2B B2 0.00019 Conv. Oral1,4-Dioxane 123-91-1 72 2B 3.6 D-ATSDR B2 0.0000077 CAL
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

1,2-Diphenylhydrazine 122-66-7 73 B2 0.00022 IRISEpichlorohydrin 106-89-8 74 2A 0.001 IRIS B2 0.0000012 IRIS1,2-Epoxybutane 106-88-7 75 0.02 IRISEthyl acrylate 140-88-5 76 2B B2Ethyl benzene 100-41-4 77 1 IRIS D 0.0000025 CALEthyl carbamate 51-79-6 78 2B 0.00029 CALEthyl chloride 75-00-3 79 10 IRISEthylene dibromide 106-93-4 80 2A 0.009 IRIS LH 0.0006 IRISEthylene dichloride 107-06-2 81 2B 2.4 ATSDR B2 0.000026 IRISEthylene glycol 107-21-1 82 0.4 CALEthylene oxide 75-21-8 84 1 0.03 CAL B1 0.000088 CALEthylene thiourea 96-45-7 85 2B 0.003 P-CAL B2 0.000013 CALEthylidene dichloride (1,1-Dichloroethane) 75-34-3 86 0.5 HEAST C 0.0000016 CALFormaldehyde 50-00-0 87 2A 0.0098 ATSDR B1 0.000013 IRISDiethylene glycol monobutyl ether 112-34-5 181 0.02 HEASTDiethylene glycol monoethyl ether 111-90-0 181Ethylene glycol ethyl ether 110-80-5 181 0.2 IRISEthylene glycol ethyl ether acetate 111-15-9 181 0.3 CALEthylene glycol methyl ether 109-86-4 181 0.02 IRISEthylene glycol methyl ether acetate 110-49-6 181 0.09 CALHeptachlor 76-44-8 88 2B B2 0.0013 IRIS 0.0005 IRIHexachlorobenzene 118-74-1 89 2B 0.003 P-CAL B2 0.00046 IRIS 0.0008 IRIHexachlorobutadiene 87-68-3 90 3 0.09 P-CAL C 0.000022 IRISHexachlorocyclopentadiene 77-47-4 91 0.0002 IRIS NH

Hexachlorodibenzo-p-dioxin, mixture 19408-74-3 187 B2 1.3 IRIS 

Hexachloroethane 67-72-1 92 3 0.08 P-CAL C 0.000004 IRISHexamethylene-1,6-diisocyanate 822-06-0 93 0.00001 IRISn-Hexane 110-54-3 95 0.7 IRIS InI

Hydrazine 302-01-2 96 2B 0.0002 CAL B2 0.0049 IRIS

Hydrochloric acid 7647-01-0 97 3 0.02 IRIS
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Hydrofluoric acid 7664-39-3 98 0.014 CALHydrogen sulfide 7783-06-4 999 0.002 IRIS InI

Hydroquinone 123-31-9 99Isophorone 78-59-1 100 2 CAL C 2.7E-07 Conv. Oral

Lead compounds 7439-92-1 182 2B 0.00015 EPA OAQPS B2 

Tetraethyl lead 78-00-2 182 0.0000001 IRI

Lindane (gamma-HCH) 58-89-9 101 2B 0.0003 P-CAL B2-C 0.00031 CAL 0.0003 IRIalpha-Hexachlorocyclohexane (a-HCH) 319-84-6 101 2B 0.02 P-CAL B2 0.0018 IRIS 0.008 D-ATSDbeta-Hexachlorocyclohexane (b-HCH) 319-85-7 101 2B 0.002 P-CAL C 0.00053 IRIS technical Hexachlorocyclohexane (HCH) 608-73-1 101 2B B2 0.00051 IRIS Maleic anhydride 108-31-6 102 0.0007 CALManganese compounds 7439-96-5 183 0.00005 IRIS D

Mercuric chloride 7487-94-7 184 C 0.0003 IRI

Mercury (elemental) 7439-97-6 184 0.0003 IRIS D 

Methyl mercury 22967-92-6 184 C 0.0001 IRI

Phenylmercuric acetate 62-38-4 184 0.00008 IRI

Methanol 67-56-1 103 4 CALMethoxychlor 72-43-5 104 3 D 0.005 IRI

Methyl bromide 74-83-9 105 0.005 IRIS D

Methyl chloride 74-87-3 106 0.09 IRIS InI

Methyl chloroform (1,1,1-Trichloroethane) 71-55-6 107 5 IRIS InI

Methyl isobutyl ketone 108-10-1 111 3 IRIS InI

Methyl isocyanate 624-83-9 112 0.001 CAL

Methyl methacrylate 80-62-6 113 0.7 IRIS E

Methyl tert-butyl ether 1634-04-4 114 3 IRIS 2.6E-07 CAL

4,4'-Methylene bis(2-chloroaniline) 101-14-4 115 2A B2 0.00043 CALMethylene chloride 75-09-2 116 2B 1 ATSDR B2 4.7E-07 IRISMethylene diphenyl diisocyanate 101-68-8 117 0.0006 IRIS InI

4,4'-Methylenedianiline 101-77-9 118 2B 0.02 CAL 0.00046 CAL

Naphthalene 91-20-3 119 0.003 IRIS C 0.000034 CAL
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Nickel compounds 7440-02-0 186 2B 0.00009 ATSDR A

Nickel oxide 1313-99-1 186 0.0001 CAL

Nickel refinery dust NI_DUST 186 A 0.00024 IRISNickel subsulfide 12035-72-2 186 0.00005 CAL A 0.00048 IRISNitrobenzene 98-95-3 120 2B 0.009 IRIS LH 0.00004 IRIS2-Nitropropane 79-46-9 123 2B 0.02 IRIS B2 0.0000056 OAQPSNitrosodimethylamine 62-75-9 125 2A B2 0.014 IRISN-Nitrosomorpholine 59-89-2 126 2B 0.0019 CALParathion 56-38-2 127 3 CPolychlorinated biphenyls 1336-36-3 136 2A B2 0.0001 IRIS Aroclor 1016 12674-11-2 136 0.00007 IRIAroclor 1254 11097-69-1 136 0.00002 IRIPentachloronitrobenzene 82-68-8 128 3 C 0.000074 Conv. OralPentachlorophenol 87-86-5 129 2B 0.1 P-CAL B2 0.0000051 CALPhenol 108-95-2 130 3 0.2 CAL InI

p-Phenylenediamine 106-50-3 131Phosgene 75-44-5 132 0.0003 IRIS InIPhosphine 7803-51-2 133 0.0003 IRIS InI

Phosphorus, white 7723-14-0 134 0.00007 P-CAL D

Phthalic anhydride 85-44-9 135 0.02 CAL

Polybrominated biphenyls 59536-65-1 187 B2 0.0025 Conv. Oral 0.000007 HEASAcenaphthene 83-32-9 187 D 0.06 IRI

Acenaphthylene 206-96-8 187 D 2-Aminoanthraquinone 117-79-3 187 0.0000094 CAL 

Anthracene 120-12-7 187 3 D 0.3 IRI

Benzo(a)anthracene 56-55-3 187 2A B2 0.00011 CAL 

Benzo(b)fluoranthene 205-99-2 187 2B B2 0.00011 CAL Benzo[j]fluoranthene 205-82-3 187 2B 0.00011 CAL Benzo(k)fluoranthene 207-08-9 187 2B B2 0.00011 CAL Benzo(g,h,i)perylene 191-24-2 187 3 D 
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Benzo(a)pyrene 50-32-8 187 2A B2 0.0011 CAL Benzo(e)pyrene 192-97-2 187 3Carbazole 86-74-8 187 3 B2 0.0000057 Conv. Oral beta-Chloronaphthalene 91-58-7 187 0.08 IRIChrysene 218-01-9 187 3 B2 0.000011 CAL Dibenz[a,h]acridine 226-36-8 187 2B 0.00011 CAL Dibenz[a,j]acridine 224-42-0 187 2B 0.00011 CAL Dibenz(a,h)anthracene 53-70-3 187 2A B2 0.0012 CAL 7H-Dibenzo[c,g]carbazole 194-59-2 187 2B 0.0011 CAL Dibenzo[a,e]pyrene 192-65-4 187 2B 0.0011 CAL Dibenzo[a,h]pyrene 189-64-0 187 2B 0.011 CAL Dibenzo[a,i]pyrene 189-55-9 187 2B 0.011 CAL Dibenzo[a,l]pyrene 191-30-0 187 2B 0.011 CAL 7,12-Dimethylbenz(a)anthracene 57-97-6 187 0.071 CAL 1,6-Dinitropyrene 42397-64-8 187 2B 0.011 CAL 1,8-Dinitropyrene 42397-65-9 187 2B 0.0011 CAL Fluoranthene 206-44-0 187 3 D 0.04 IRI

Fluorene 86-73-7 187 3 D 0.04 IRIIndeno(1,2,3-cd)pyrene 193-39-5 187 2B B2 0.00011 CAL 

3-Methylcholanthrene 56-49-5 187 0.0063 CAL 5-Methylchrysene 3697-24-3 187 2B 0.0011 CAL 1-Methylnaphthalene 90-12-0 187 0.07 ATSDR2-Methylnaphthalene 91-57-6 187 InI 0.04 ATSDR 

5-Nitroacenaphthene 602-87-9 187 2B 0.000037 CAL 

6-Nitrochrysene 7496-02-8 187 2B 0.011 CAL 2-Nitrofluorene 607-57-8 187 2B 0.000011 CAL 1-Nitropyrene 5522-43-0 187 2B 0.00011 CAL 4-Nitropyrene 57835-92-4 187 2B 0.00011 CAL Octabromodiphenyl ether 32536-52-0 187 D 0.003 IRI

Phenanthrene 85-01-8 187 D 
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Pyrene 129-00-0 187 D 0.03 IRI

1,3-Propane sultone 1120-71-4 137 2B 0.00069 CAL

Propionaldehyde 123-38-6 139 0.008 IRIS InI

Propoxur 114-26-1 140 B2Propylene dichloride 78-87-5 141 0.004 IRIS B2 0.000019 Conv. Oral

Propylene oxide 75-56-9 142 2B 0.03 IRIS B2 0.0000037 IRISQuinoline 91-22-5 144 LHSelenium compounds 7782-49-2 189 0.02 CAL D

Hydrogen selenide 7783-07-5 189 0.00008 P-CAL

Selenious acid 7783-00-8 189 DSelenium dioxide 7446-08-4 189 0.02 CALSelenium disulfide 7488-56-4 189 0.02 CALSelenium sulfide 7446-34-6 189 0.02 CAL B2

Selenourea 630-10-4 189Styrene 100-42-5 146 2B 1 IRIS

Styrene oxide 96-09-3 147 2A 0.006 P-CAL2,3,7,8-Tetrachlorodibenzo-p-dioxin 1746-01-6 148 4E-08 CAL B2 33 EPA ORD 1E-09 ATSD1,1,2,2-Tetrachloroethane 79-34-5 149 3 C 0.000058 IRISTetrachloroethene 127-18-4 150 2A 0.27 ATSDR B2-C 0.0000059 CALTitanium tetrachloride 7550-45-0 151 0.0001 ATSDRToluene 108-88-3 152 3 5 IRIS InI

2,4-Toluene diamine 95-80-7 153 B2 0.0011 CAL

2,4/2,6-Toluene diisocyanate mixture (TDI) 26471-62-5 154 2B 0.00007 IRIS 0.000011 CALo-Toluidine 95-53-4 155 2B B2 0.000051 CALToxaphene 8001-35-2 156 2B B2 0.00032 IRIS 1,2,4-Trichlorobenzene 120-82-1 157 0.2 HEAST D

1,1,2-Trichloroethane 79-00-5 158 3 0.4 P-CAL C 0.000016 IRIS

Trichloroethylene 79-01-6 159 2A 0.6 CAL B2-C 0.000002 CAL2,4,5-Trichlorophenol 95-95-4 1602,4,6-Trichlorophenol 88-06-2 161 B2 0.0000031 IRIS
Table 1. Prioritized Chronic Dose-Response 

Values (4/27/2010). Revisions since 06/12/07 are shown in red. CAS NO. = Chemical Abstracts Services number for the compound. HAP NO. = 

Position of the compound on the HAP list in the Clean Air Act (112[b][2]). "999" denotes substances under consideration for listing. 

CHEMICAL NAME CAS NO.

HAP 

NO.

IARC WOE mg/m3 SOURCE

EPA 

WOE 1/(ug/m3) SOURCE mg/kg/d SOURCE

Sources: IRIS = Integrated Risk 

Information System; ATSDR = US Agency for Toxic Substances and Disease Registry; D-ATSDR = draft ATSDR; CA = California EPA; PCAL = Proposed CAL; HEAST = EPA Health Effects Assessment Tables; Conv. Oral = Oral unit risk converted to inhalation.

IARC WOE = weight-ofevidence for carcinogenicity in humans (1 - carcinogenic; 2A - probably carcinogenic; 2B - possibly carcinogenic; 3 - not classifiable; 4 - probably not carcinogenic).

EPA WOE (1986 guidelines) = weight-ofevidence for carcinogenicity under the 1986 EPA cancer guidelines: A - human carcinogen; B1 - probable carcinogen, limited human evidence; B2 - probable carcinogen, sufficient evidence in animals; C - possible human carcinogen; D - noclassifiable E - evidence of noncarcinogenicity. 

Table 1. Prioritized Chronic Dose-Response Values for Screening Risk Assessments (4/27/2010)

CHRONIC INHALATION CH

NONCANCER CANCER NONCANCER 

Triethylamine 121-44-8 162 0.007 IRISTrifluralin 1582-09-8 163 3 C 0.0000022 Conv. Oral 0.0075 IRIUranium compounds 7440-61-1 188 0.0003 ATSDRUranium, soluble salts URANSOLS 188Vinyl acetate 108-05-4 165 2B 0.2 IRISVinyl bromide 593-60-2 166 2A 0.003 IRIS B2 0.000032 HEASTVinyl chloride 75-01-4 167 1 0.1 IRIS CH 0.0000088 IRISVinylidene chloride 75-35-4 168 0.2 IRIS SE

m-Xylene 108-38-3 171o-Xylene 95-47-6 170Xylenes (mixed) 1330-20-7 169 0.1 IRIS InI