The use of chemical and biological parameters to characterize complex industrial effluents

Hitherto, the concern for possible environmental effects due to aqueous industrial discharges has been directed toward clearly observable effects such as eutrophication and fish kills. However, the development of environmental toxicology and chemistry has made it clear that more subtle and potential long-term effects also have to be taken into account in the regulatory work. The Swedish Environment Protection Board has recently completed a research project: "Characterization of Industrial Effluents." Initially, analytical methods and laboratory tests, originally developed for single substances, were identified. Laboratories were then invited to participate, with their own methods, in ring tests with a variety of industrial effluent waters. The studies indicated that a number of chemical and biological methods can be used to characterize complex industrial wastewaters with regard to their content of toxic, persistent, and bioaccumulative substances. A frame program was established for the construction of test batteries adapted to various administrative regulatory purposes. To date, this strategy has been applied to several industries by the authorities, resulting in valuable experience of cost-effectiveness and the usefulness in the administrative decision-making process. Besides the studies on single industries, two other approaches have been applied, namely for the assessment of the impact of several industries on a common receiving water body, and for the evaluation of a whole industrial branch, that is, kraft pulp mill bleachery effluents. In the latter case, the studies have resulted in a ranking of processes and treatment methods to protect the environment.