Alternative methods in toxicology tests: In vitro toxicity

Toxicity testing is required for new chemicals being introduced onto the market. The use of animals in evaluating chemical safety is costly and time consuming. Furthermore, there is the ethical need to develope alternative methods to reduce the required number of animals. The newin vitro assays offer numerous advantages such as speed, reproducibility and control of test conditions, and increased sensitivity. Although the dermal irritation assays might be substituted by thein vitro tests in the near future (Duffy, 1989), much work is required to evaluate organ toxicity within vitro methods. We present data regarding the use of Balb/3T3 mice fibroblasts and primary rat hepatocytes as test systems forin vitro toxicity. The end-points we have analysed are total protein content, dye accumulation in lysosomes, reductase mytochondrial activity, intracellular content and leakage of enzymes into the medium.