Proposal and application of an ecotoxicity biotest based on Escherichia coli.

The authors propose the use of an ecotoxicity biotest based on Escherichia coli for the sanitary control of water. The sensitivity of the proposed model was evaluated using a group of representative toxicants, and its response (synergism, additive or antagonism) to toxicants was observed. Finally, the biotest was applied to 124 water samples from rivers, underground sources, drinking water and wastewater. The results of the biotest were compared with the sanitary classification of the waters.