Mepanipyrim

The Food Safety Commission of Japan (FSCJ) conducted a risk assessment of mepanipyrim (CAS No.110235-47-7), an anilinopyrimidine fungicide, based on results from various studies. Major adverse effects of mepanipyrim observed were hepatocellular hypertrophy, hepatocellular degeneration, and increased kidney weight in rats. Neither reproductive toxicity, teratogenicity nor genotoxicity was observed. Mepanipyrim (parent compound only) was identified as a chemical for the residue definition for dietary risk assessment in agricultural products. FSCJ adopted the no-observed-adverse-effect level (NOAEL) of 7.34 mg/kg bw/day, obtained in a two-year combined chronic/carcinogenicity study in rats, appropriate for specification of an acceptable daily intake (ADI). An ADI was thus specified as 0.073 mg/kg bw/day, applying a safety factor of 100 to the NOAEL. The lowest NOAEL for adverse effects that would be likely to be elicited by a single oral administration of mepanipyrim was 400 mg/kg bw obtained in an acute neurotoxicity study in rats. Consequently, FSCJ specified an acute reference dose (ARfD) of 4 mg/kg bw, applying a safety factor of 100 to the NOAEL.