Toxicity of mixtures of aquatic contaminants using the luminescent bacteria bioassay

The toxic effect of single organic contaminants to aquatic biota is relatively easy to assess using classic aquatic toxicity bioassays. Unfortunately, contaminants are present in the aquatic environment in mixtures of unknown composition. Moreover, antagonistic and synergistic interactions make the prediction of the real environmental hazard posed by organic contaminants more complicated. A mathematical algorithm has been developed to predict the toxicity of mixtures of organic contaminants to aquatic biota using toxicity data for the individual components of the mixture. The Microtox® toxicity bioassay was used to obtain the toxicity data for a set of chlorinated phenols that were used as test compounds to validate the model. The unique characteristics of the Microtox bioassay make it a perfect tool to confirm experimentally the ability of the model to estimate the combined toxic effect of mixtures of organic contaminants.