POTENTIAL OF HUMAN LUNG-CELLS FOR PREDICTING ACUTE CYTOTOXICITY

Human fetal lung fibroblasts (HFL1) were studied in culture to evaluat e their potential as a screen for cytotoxicity. The cytotoxic concentr ations determined in vitro were compared with established human and an imal toxicity data. Confluent monolayers were incubated in the absence or presence of increasing concentrations of test chemicals for 24 hou rs, and the MTT assay was used to assess toxicity. Inhibitory concentr ations were extrapolated from concentration-effect curves after linear regression analysis. Comparison of the cytotoxicity data with rodent lethal concentrations and human lethal concentrations obtained from th e testing of 50 chemicals in human lung cells, suggests that the exper imental IC50 values are as accurate as predictors of human toxicity as the equivalent toxic blood concentrations derived from rodent LD50 te sts. In addition, evaluation of the first 15 chemicals reveals no sign ificant differences between results from continuous cell lines of huma n and rodent origin. Together with a related battery of tests, cell cu lture procedures have the potential to supplement or replace current a nimal protocols in screening chemicals for human toxicity.