Predicting the toxicity of complex mixtures using artificial neural networks

Industrial and municipal wastewaters constitute major sources of contamination of the aquatic compartment and represent a threat to aquatic life. Artificial neural networks based on three different learning paradigms were studied as a means of predicting acute toxicity to trout (5 days exposure to wastewaters) using input data from two simple microbiotests requiring only 5 or 15 min of incubation. These microbiotests were 1) the chemoluminescent peroxidase (Cl-Per) assay, which can detect radical scavengers and enzymeinhibiting substances, and 2) the luminescent bacteria toxicity test (MicrotoxTM), in which reduction of light emission by bacteria during exposure is taken as a measure of toxicity. The responses obtained with the trout bioassay, the Cl-Per and the MicrotoxTM test were analyzed through statistical correlation (Pearson product-moment correlation), unsupervised