Tetrachlorohydroquinone (TCHQ), a metabolite of the organochlorine biocide pentachlorophenol, is cytotoxic to RTL-W1 rainbow trout liver cells (EC50 = 1.55 µM in a neutral red assay). TCHQ increases production of reactive oxygen species (ROS), inhibits apoptosis, and induces loss of mitochondrial membrane potential and necrosis in splenocytes.
