CYTOTOXICITY OF ORGANIC ENVIRONMENTAL CHEMICALS TO FISH LIVER-CELLS (PLHC-1)

There is a need in aquatic toxicology to develop alternative assays fo r the assessment of toxicity in fish. In recent years, in vitro assays have been developed for scientific, ethical and economical reasons. I n this study, the fish hepatoma cell line PLHC-1 (Hightower & Renfro, 1988) was employed for assessing the cytotoxicity of environmental che micals, to derive structure activity relationship, and to compare in v itro with in vivo toxicity. The cytotoxicity of several important orga nic compounds, including chloro- and nitrophenols, estrogenic alkylphe nols and sulphonic acids, as well as organotin compounds (Bruschweiler et al., 1995), was assessed. Two cytotoxicity assays were performed: inhibition of neutral red uptake (NR) into lysosomes based on cell mem brane damage, and the tetrazolium salt reduction (MTT) assay to determ ine inhibition of mitochondrial succinate dehydrogenase. A high correl ation between the two assays was found. Of the various compounds, orga notins were most toxic, followed by higher substituted phenols, lower substituted phenols and sulphonic acids. The in vitro cytotoxicity, sh owed a similar trend as the in vivo acute toxicity of fish for organot ins and substituted phenols. Furthermore, a positive trend between cyt otoxicity and n-octanol-water partition coefficients of the chemicals was found. The results indicate that cytotoxicity assays using this me tabolically active hepatoma cell line are a promising tool in the firs t evaluation and toxicity screening of che micals prone to contaminate aquatic systems. Copyright (C) 1996 Elsevier Science Ltd