Benzo(a)pyrene (Benzo(d,e,f) chrysene, 3,4-Benzopyrene, 6,7- Benzopyrene) Cas No. 50-32-8

Benzo(a)pyrene

(Benzo(d,e,f) chrysene, 3,4-Benzopyrene, 6,7-

Benzopyrene)

Cas No. 50-32-8

Potential sources and exposure

Benzo(a)pyrene (B(a)P) is a PAH. The reader should refer to the general

profile on PAHs for exposure information.

Physical and chemical properties

Value

Property

Molecular weight

252.3 g/mol

1.2 10-3 mg/L at 20 oC

Water solubility

5.60 10-9 mm Hg at 25 oC

Vapor pressure

Koc

5,500,000 mL/g

log Kow

6.06

1.55 10-6 atm-m3/mol

Henry's Law Constant

Toxicity

Lung and skin tumors have been induced in humans by mixtures of PAHs

known to contain benzo(a)pyrene (cigarette smoke, roofing tar, and coke oven

emissions). It is not possible, however, to conclude from this information that

benzo(a)pyrene is the responsible agent (IRIS 1992).

Benzo(a)pyrene is a complete carcinogen when applied to the skin of mice,

rats, and rabbits (IARC 1983). Subcutaneous or intramuscular benzo(a)pyrene

injection has resulted in local tumors in mice, rats, guinea pigs, monkeys, and

hamsters (IARC 1973). Intratracheal instillation of benzo(a)pyrene products

produced increased incidences of respiratory tract neoplasms in both male and

female Syrian hamsters (IRIS 1992).

Benzo(a)pyrene administered orally to rats and hamsters produces stomach

tumors. Dietary benzo(a)pyrene was administered in a subchronic study to male

and female CFW-Swiss mice. Stomach tumors were observed in mice consuming

20 or more mg/kg benzo(a)pyrene. Incidence was apparently related both to the

dose and the number of administered doses.

D16

Appendix D Toxicological Profiles