TOXICITY OF ETHANOL IN LOW CONCENTRATIONS - EXPERIMENTAL EVALUATION IN CELL-CULTURE

Purpose: To define the threshold ethanol concentration that is toxic t o cultured cells. Methods: Three malignant cell lines and freshly isol ated normal rat hepatocytes were exposed to 0-50% (vol.) ethanol (conc entrations used were 0, 5, 10, 15, 20, 25, 30, 40 and 50%) on tissue c ulture plates for 0.25-60 min (exposure times used were 0.25, 5, 10, 2 0, 30, 40. 50 and 60 min). Cytotoxicity was estimated by trypan blue e xclusion test and from H-3-thymidine incorporation. Results: All cells were killed by a 15-s exposure to 30-40% ethanol while a concentratio n as low as 15-20% gave a total response after 5-10-min exposures. Aft er a one-hour exposure of F9 carcinoma cells and hepatocytes, a total or nearly total response was achieved with 10% ethanol. The cytotoxic effect was thus dependent both on the exposure time and on the concent ration of ethanol. There were no significant differences in ethanol to lerance among the cell types. Conclusion: Ethanol seemed to kill cells in the cell culture effectively in much lower concentrations than tho se currently used in tumour ablation.