Hemotoxicity of chlorpropham (CIPC) in F344 rats

Chlorpropham[Isopropyl-N-(3-chlorophenyl)carbamate; CIPC] is a widely used sprout suppressant. Groups of ten male and ten female F344 rats were given 0, 7500, 15,000 or 30,000 ppm of CIPC in the diet for 13 weeks. Body weight gain of male and female rats in the 30,000 ppm-group was depressed. Spleen and liver weights of male and female rats in the treated groups were dose-dependently increased. Red blood cell count, hemoglobin concentration, hematocrit, mean corpuscular hemoglobin concentration and platelet count were decreased in male and female rats of the treated groups. Methemoglobin level, mean corpuscular volume and mean corpuscular hemoglobin were increased in male and female rats of the treated groups. Those hematological changes were dose-dependent and were marked in the 15,000 and 30,000 ppm-groups. White blood cell count of male and female rats in the 30,000 ppm-group were significantly higher than those of the control group. Congestion, increased hemosiderin deposition, increased extramedullary hemopoiesis, lymphoid atrophy and fibrosis were seen in spleen of male and female rats of all treated groups in a dose-dependent manner. Hemopoietic cell hyperplasia was marked in bone marrow of male and female rats in all treated groups. The results suggested that the erythrocyte is one of the primary targets of CIPC toxicity in rats.