Acute and subchronic toxicity of 2,4-dichlorophenol in CD-1 mice

Abstract

The acute oral LD50 of 2,4-dichlorophenol (2,4-DCP) employing corn oil as vehicle was determined to be 1352 mg/kg for female and 1276 mg/kg for male CD-1 mice. CD-1 mice of both sexes were exposed to 2,4-DCP in drinking water containing 10% Emulphor for 90 days at concentrations of 0.2, 0.6, and 2.0 mg/ml providing theoretical daily doses of 50, 150, and 500 mg/kg. These concentrations resulted in mean daily doses of 50, 143, and 491 mg/kg for females and 40, 114, and 383 mg/kg for males. In both sexes, fluid consumption was lower in the vehicle control group (10% Emulphor) and in the 2,4-DCP treated groups than in the naive controls (deionized water). There were no biologically significant differences in body weight gain between females or males in the vehicle control and experimental groups. No differences were found in terminal organ weights or organ weight ratios in either sex. Hematological differences were observed in males only and included an increase in leukocytes (high dose) and an increase in polymorphonuclears (low dose). Clinical chemistry parameters were altered in females only and included a decrease in creatinine (low dose), an increase in BUN/creatinine ratio (mid dose), and an increase in ALP (high dose). In an assessment of the hepatic microsomal mixed function oxidase system, no significant differences were found in the components of the system, component activity, the kinetics of ethylmorphine N-demethylase, or the metabolism of testosterone. Administration of 2,4-DCP to CD-1 mice of both sexes for 90 days at mean doses of 40 to 491 mg/kg/day in drinking water did not elicit either consistent compound-related or dose-dependent significant toxicological effects.