Sex difference in inhalation toxicity of p-dichlorobenzene (p-DCB) in rats.

The organ distribution and toxicity of p-dichlorobenzene (p-DCB) were compared in male and female rats after inhalation of 500 ppm of p-DCB for 24 h in a whole-body chamber. Concentrations of p-DCB in the serum, liver, kidney and fatty tissues were measured by gas chromatography at intervals during and up to 24 h after the treatment. Though no significant differences in the serum levels were observed between male and female rats, the p-DCB values in the livers of female rats were significantly higher than those of male rats. Conversely, significantly higher levels were found in the kidneys of male than of female rats. The distribution results thus appeared to correlate with the fact that nephrotoxic changes were observed only in male rats and that the appearance of minor hepatotoxic changes was limited to females.