home edit2 whole TSD November 2002 PDF format - OEHHA

fibrosarcomas, stromal sarcomas, capsular sarcomas or hemangiosarcomas were noted in female rats.
Tumor incidence data is listed in Table 2.
Table 2:
Incidence of splenic tumors in male CD-F rats fed diets containing aniline hydrochloride
(CIIT, 1982)
Dietary aniline hydrochloride
concentration (approximate)
(ppm)
Aniline hydrochloride
exposure level
(mg/kg body weight/day)
Human equivalent dose 1
(mg/kg/day) -1
Tumor
incidence 2
0 0 0 0/64
200 10 1.23 0/90
600 30 3.69 1/90
2000 100 12.29 31/90
1. Calculation of the doses included a correction for the difference in molecular weight of aniline
and aniline hydrochloride (compound administered) (US EPA, 1992).
2. Tumor incidence includes fibrosarcomas, stromal sarcomas, capsular sarcomas, and
hemangiosarcomas as reported by US EPA (1992).
Syrian golden hamsters (15 male and 15 female) received subcutaneous injections of aniline (521 mg/kg
body weight; total dose 9219 mg/kg) for 52 weeks (Hecht et al., 1983). Although mean survival was
reduced in the aniline-treated groups, no increase in tumor incidence was observed. However, the
experimental exposure was less than lifetime, and the number of exposed animals was small.
IV.
DERIVATION OF CANCER POTENCY
Basis for Cancer Potency
Cancer potency values are based on the most sensitive site, species and study demonstrating
carcinogenicity of a particular chemical, unless other evidence indicates that the value derived from that
data set is not appropriate (CDHS, 1985). Male rat spleen tumor data (CIIT, 1982) was used to
generate a cancer potency factor for aniline. Male rats in the high-dose group showed a marked
increase in the incidence of splenic tumors (see Table 2). US EPA (1994) also noted the presence of
stromal hyperplasia and fibrosis of the splenic red pulp in high-dose males and, to a lesser degree, in
females; this may represent a precursor lesion of sarcoma.
Methodology
A linearized multistage procedure (US EPA,1980) was used to calculate a slope factor of 5.7 E-3
(mg/kg-day) -1 from the CIIT (1982) male splenic tumor incidence data. Calculation of the transformed
doses for aniline included a correction for the difference in molecular weights of aniline and aniline
hydrochloride, the form in which the compound was administered in the NCI and CIIT bioassays.
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