Subchronic Inhalation Toxicity Study of 1,3-Dichloro-2-propanol in Rats

Abstract

The subchronic toxicity of 1,3-dichloro-2-propanol (1,3-DCP) was investigated in Fischer 344 rats after 13 weeks of repeated, whole-body inhalation exposure. Groups of 10 rats of each sex were exposed to 1,3-DCP vapor by whole-body inhalation exposure at concentrations of 0, 5, 20 or 80 ppm for 6 h/day, 5 days/week for 13 weeks. All of the rats were sacrificed at the end of the treatment period. During the test period, clinical signs, mortality, body weights, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights and histopathology were assessed. At 80 ppm, a decrease in the body weight gain, an increase in the urine protein and leukocyte counts and an increase in the liver and kidney weights were observed in both genders. Hematological and serum biochemical investigations revealed decreases in hemoglobin (HB), hematocrit (HCT), mean corpuscular volume (MCV) and mean corpuscular HB, as well as increases in the platelet (PLT) count, serum aspartate aminotransferase and alanine aminotransferase. The number of white blood cells was significantly lower in males than in controls, but this was not the case in females. Histopathological alterations included an increase in the incidence of multifocal necrosis, inflammation, pigmentation, biliary hyperplasia and the foci of cellular alteration of the liver and chronic nephropathy and protein cast of the kidney. At 20 ppm, decreases in HCT and MCV and increases in the liver and kidney weights were observed in both genders. A decrease in the HB of females and an increase in the PLT count of females were also observed. Histopathological alterations included slight increases in the incidences of hepatic necrosis, hepatic inflammation and chronic nephropathy. At 5 ppm, we found decreases in the MCV of males and the HB of females, as well as an increase in the liver weight of both genders. In the present experimental conditions, the target organs were determined to be the liver, kidney and blood cells in rats. The no-observed-adverse-effect level was considered to be <5 ppm/6 h/day and the low-observed-adverse-effect level was believed to be 5 ppm/6 h/day in rats.