Benzo(a)anthracene (Benz(a)anthracene; 1,2-Benz(a)anthracene; Benzo(a)phenanthrene) Cas No. 56-55-3

Benzo(a)anthracene

(Benz(a)anthracene; 1,2-Benz(a)anthracene;

Benzo(a)phenanthrene)

Cas No. 56-55-3

Potential sources and exposure

Benzo(a)anthracene is a PAH. The reader should refer to the general profile

on PAHs for exposure information.

Physical and chemical properties

Property

Value

Molecular weight

228.3 g/mol

-3

Water solubility

5.7 10 mg/L at 20 C

-8

Vapor pressure

2.20 10 mm Hg at 20 C

Koc

1,380,000 mg/L

log Kow

5.6

-6

Henry's Law Constant

1.16 10 atm-m /mol

Toxicity

Although there are no human data that specifically link exposure to

benzo(a)anthracene to human cancers, benzo(a)anthracene is a component of

mixtures associated with human cancer. These include coal tar residues, coke

oven emissions, and cigarette smoke (IRIS 1992).

Several studies indicate that benzo(a)anthracene is carcinogenic in animals,

and IARC has evaluated that evidence as sufficient to establish the

carcinogenicity of benzo(a)anthracene in animals (IARC 1983).

Benzo(a)anthracene administration caused an increase in the incidence of tumors

by gavage, dermal application (IARC 1973); and both subcutaneous injection,

and intraperitoneal injection assays. A carcinogenic potency factor (CPF) has not

been developed by the USEPA. Based on the work of Bingham and Falk (1969),

it was estimated that benzo(a)anthracene has a relative potency - to

benzo(a)pyrene - of 0.145. (Potency is approximately 14.5 percent of that of

benzo(a)pyrene). This value can be used in the relative potency approach for

estimating carcinogenic risk.

Extensive testing for mutagenicity has been documented (IARC 1983) with

mostly positive results (IRIS 1992).

D11

Appendix D Toxicological Profiles