Production of Trichloromethylphenol from Organo-phosphorus Pesticide Fenitrothion by Chlorination

In this study, it was attempted to identify the mutagen produced by chlorination of insecticide fenitrothion using a quadrupole GC-MS and a high-resolution GC-MS. From the mass spectra obtained by the GC-MS, the chemical structures of two unidentified compounds were extrapolated: one was identified as 2-chloro-5-methyl-4-nitrophenol by comparison to the synthesized standard compound, while another one was identified as trichloro-3-methylphenol by high-resolution GC-MS. The mutagenicity of these identified chlorination by-products (CBPs) of fenitrothion were evaluated by the Ames assay (preincubation method) using Salmonella typhimurium TA100 without exogenous activation by S9 mix (TA100-S9). However, none were found to be mutagenic. Further studies are needed to identify the mutagenic CBP(s) of fenitrothion.