Identification of chloro-nitro-trifluoromethyl-substituted dibenzo-p-dioxins in lampricide formulations of 3-trifluoromethyl-4-nitrophenol: assessment to induce mixed function oxidase activity

摘要

The contamination of field formulations of the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) by a dibenzo-p-dioxin containing -chloro, -nitro, and -trifluoromethyl substitutents was suspected form chemical fractionations of a TFM formulation that were directed by mixed function oxidase (MFO)induction in rainbow trout. Three dioxin isomers containing these substituents in field formulations were identified by gas chromatography-mass spectormetry (GC-MS). Short-term waterborne exposure to a mixture of two isomers, 2-trifluoromethyl-3-nitro-7-(an 8)-chloro-dibenzo-p-dioxin, elevated MFO activity in trout, with a threshold between 0.148 and 0.745 nM (4.1-20.5 ng/L).