Toxic effects of chromium acetate hydroxide on cells cultivated in vitro

Many human activities, particularly industrial ones, result in an ever-grow ing production of toxic waste materials. The dynamics of the toxic effects of chromium acetate hydroxide, which is found in high concentrations in a w aste sediment produced in the Czech Republic, were assessed by using a batt ery of in vitro tests carried out on two cell lines: L-929 (mouse fibroblas ts) and Hep 2 (human laryngeal cells). Various markers of cell damage were assessed by phase-contrast, video and fluorescence microscopy, fluorometry, and DNA analysis. Chromium acetate hydroxide, over a concentration range o f 1-0.02mol/l induced immediate cell death by fixation, whereas, at 0.002mo l/l, the treated cells died in a much slower, more discrete manner. All the detected markers of cell damage, whether immediate or slow, clearly demon strated that the cells died by necrosis. On the other hand. test concentrat ion of 0.001mol/l appeared to constitute a threshold at which no pathologic al changes of Hep 2 cells were observed over 96 hours. We conclude that chr omium acetate hydroxide has a high toxic potential in vitro, which should b e considered when studying the toxicity of waste materials containing it.