Carcinogenicity of methylmercury chloride in ICR mice: preliminary note on renal carcinogenesis

ICR mice (60/group) were fed diets containing methylmercury chloride (MMC) in 0, 15 or 30 ppm for 78 weeks. The majority of mice in the 30-ppm group died due to the neurotoxicity by week 26. The first renal mass was grossly seen in a male of the 15-ppm group at week 58. Histopathology on kidney tissue from all animals surviving after 53 weeks revealed renal tumors in 13 of 16 males of the 15-ppm group in contrast with 1 of 37 males of the control. No renal tumors were seen in the female treated groups and/or control groups.