The environmental risks of industrial waste disposal: an experimental approach including acute and chronic toxicity studies.

The toxicity of 15 leachates of various solid industrial wastes accepted in an engineered landfill has been studied. A cost-effective battery of tests allowing evaluation of acute and chronic toxicity, as well as genotoxicity, and investigations on different trophic levels in the aquatic environment has been used. Acute toxicity was tested on bacteria (Microtox assay with Photobacterium phosphoreum) and microcrustaceans (Daphnia magna immobilization assay). A growth inhibition test of microalgae was carried out on Raphidocelis subcapitata. A 28-day chronic test with Daphnia magna was used to detect effects on reproduction. Genotoxicity was evaluated by means of the Ames test conducted on the crude aqueous phase and also on the concentrated fractions of water-extractable micropollutants (liquid-liquid and freeze-dried extracts). Chemical analyses of leachates were carried out simultaneously. The toxicity varied greatly between the different wastes. Toxic effects were observed in the short and/or in the long term. Four samples were potentially genotoxic. In most cases, toxicity registered could not be correlated with results of the chemical analyses. This study demonstrates the usefulness of associating a toxicological monitoring with chemical analyses in waste management.