ECOTOXICOLOGY - AN ANALYSIS OF THE RHINE POLLUTION CAUSED BY THE SANDOZ CHEMICAL ACCIDENT, 1986

A fire at a chemical manufacturing plant at Schweizerhalle (near Basel ) in November 1986 and the subsequent release of toxic agrochemicals i nto the River Rhine is taken as a basis for discussion of some problem s and needs in ecotoxicological research. The 5-8 tons of pesticides t hat entered the river killed a great portion of the eel population and injured other fish species as well as macroinvertebrates as far downs tream as The Netherlands. Fundamental scientific research must provide better means to deal with such problems as contamination of drinking water and toxicity to whole biocenoses, both of which were handled wit h great uncertainty during and after the accident. Especially serious is the lack of knowledge about the chronic effects of mixtures of chem icals to individuals and entire ecosystems. Considering the number of anthropogenic chemicals (approximately 70 000) and the great variety o f species (some 2-3 million) there seems to be no hope of ever being a ble to monitor or test all of them. Thus, there is an urgent need for generally applicable principles and concepts. A discussion of the rela tionship between toxic effects to fish, exposure time and concentratio n provides some indication of the direction in which research might pr oceed. Finally, eight postulates pertaining to ecotoxicology summarise what has been learnt from the analysis of this chemical spill.