Subchronic toxicity and genotoxicity of diiodomethyl-p-tolylsulfone (DIMPTS) in laboratory animals

These studies were conducted to determine subchronic toxicity and genotoxicity of the biocide diiodomethyl-p-tolysulfone (DIMPTS) in rats and dogs. Male and female Sprague–Dawley rats and Beagle dogs were administered DIMPTS for 90-days via the diet at 0, 5, 20, and 80 mg/kg/day to rats and via capsules at 0, 2, 10, and 60 mg/kg/day to dogs. In rats, the only treatment-related finding was squamous metaplasia of the salivary gland duct in the 80 mg/kg/day group. In dogs, female body weights in the high-dose group were significantly lower than controls. Altered clinical pathology parameters were considered secondary to inflammatory changes observed in some of the dogs. Treatment-related alterations were found in the thyroid glands, salivary glands, GI-tract in the mid- and/or high-dose groups. DIMPTS was negative in the four in vitro and one in vivo genotoxicity assays. The toxicological effects noted in the two mammalian species are consistent with the principal toxic effects of iodine, and are proposed to arise from release of iodide from the DIMPTS molecule with toxic sequelae.

► Studies conducted to determine subchronic toxicity and genotoxicity of DIMPTS. ► DIMPTS was given orally for 90-days at 0–80 mg/kg/day to rats and at 0–60 mg/kg/day to dogs. ► Toxicity consistent with excess iodine. Rats-salivary duct metaplasia at high dose. ► Dogs – ♀: BW at high, thyroid, salivary glands, GI-tract at mid and/or high doses. ► DIMPTS not genotoxic in the four in vitro and one in vivo genotoxicity assays.