home edit2 whole TSD November 2002 PDF format - OEHHA

4-CHLORO-o-PHENYLENEDIAMINE
CAS No: 95-83-0
I. PHYSICAL AND CHEMICAL PROPERTIES (From HSDB, 1994)
Molecular weight 142.60
Boiling point
not available
Melting point 76 °C (NCI, 1978)
Vapor pressure
not available
Air concentration conversion 1 ppm = 5.83 mg/m 3
II.
HEALTH ASSESSMENT VALUES
Unit Risk Factor: 4.6 E-6 (µg/m 3 ) -1
Slope Factor: 1.6 E-2 (mg/kg-day) -1
[Male rat urinary bladder tumor data (NCI, 1978), contained in Gold et al. (1990), expedited
Proposition 65 methodology (Cal/EPA, 1992), cross-route extrapolation.]
III.
CARCINOGENIC EFFECTS
Human Studies
No studies on the potential carcinogenic effects of 4-chloro-o-phenylenediamine in humans are known
to exist.
Animal Studies
Male and female Fischer 344 (F344) rats and B6C3F 1 mice were fed diets containing 4-chloro-ophenylenediamine
(NCI, 1978). Dietary 4-chloro-o-phenylenediamine concentrations and treatment
durations for rats and mice are listed in Table 1. Treatment group sizes were 50
animals/sex/species/group, except for low-dose male rats, where a group size of 49 was used.
At study termination, 84, 84 and 70% of male mice, and 72, 88 and 78% of female mice in the control,
low-dose and high-dose groups, respectively, were still alive. Survival in treated rats was somewhat
lower; 64, 80 and 56% of male rats and 72, 84 and 54% of female rats in the control, low-dose and
high-dose groups, respectively, were still alive at study termination. Significantly increased treatmentrelated
liver tumor (hepatocellular adenomas, carcinomas) incidences were noted in both male and
female mice. These data are listed in Table 2. A significant dose-related trend was also noted in the
increased incidence of urinary bladder carcinomas in male (transitional cell papillomas, carcinomas) and
female (papillary or transitional cell carcinomas) rats (Table 2). Increases in the incidence of
forestomach tumors also occurred in both male and female rats. The forestomach tumor increases were
not statistically significant; however, these tumors are rare in F344 rats.
201