Keynote Address—Reflections on Pickle-Jar Ecology

Biological tests of effluent toxicity and appropriate formulas for application of toxicity bioassay results should be relied upon in regulating discharges of toxic effluents whenever reliance on chemical tests and chemical criteria or standards of water quality cannot be shown to be more reasonable. Some recent, pertinent recommendations made by biologists (committees) are ambiguous if not entirely inconsistent with this rule. They provide no clear guidelines for equitable regulatory action to be taken, or choice of requirements to be enforced, when recommended chemical criteria of water quality can be shown by biological tests or observations to be inappropriate to particular mixtures of chemicals being discharged, characteristics of the receiving waters, or other local circumstances. A need for reconsideration and clarification of these recommendations is indicated, and if reliance on biological, rather than chemical, tests and criteria is to be emphasized and promoted, a major redirection of research in aquatic toxicology should be considered. Formulas for application of the results of short-term toxicity bioassays of whole effluents then should be more fully developed and tested, largely through admittedly difficult and costly experiments whereby these results can be related to the harmful effects of the tested toxicants on aquatic life and fish production under conditions closely resembling natural conditions.