The assessment of industrial effluent toxicity using aquatic microorganisms, invertebrates and fish

Traditionally in the United Kingdom, the control of industrial effluent discharges into the aquatic environment has been based primarily upon physical and chemical parameters applied with reference to the aquatic toxicity of key effluent components (for example, ammonia and pH). Influenced by international developments, however, there is a trend in Europe to apply whole-effluent toxicity tests to monitor and control industrial effluent discharges. The relative sensitivity and utility of toxicity tests for providing acute and sublethal toxicity data on industrial effluents were therefore investigated. Toxicity tests were carried out on effluent samples taken from a variety of industrial sites that included liquid effluent discharges to freshwater and to marine/estuarine waters. Comparisons were made between the Microtox® test and toxicity tests with fish (Oncorhynchus mykiss, Pleuronectes platessa, Scophthalmus maximus, Pimephales promelas and Cyprinodon variegatus) and a marine crustacean (Tisbe battagliai). A summary of the toxicity data generated is presented and recommendations are made regarding future developments in effluent discharge control.