Alternative Approaches and Tests in Ecotoxicology: A Review of the Present Position and the Prospects for Change, Taking into Account ECVAM’s Duties, Topic Selection and Test Criteria
Colin H. Walker
The objectives of this review are to summarise the present position concerning the use of vertebrates in ecotoxicity testing, giving particular attention to tests that cause suffering, and to discuss in some detail, alternatives to them, and the prospects for change. The report has been written with the objectives of the European Centre for the Validation of Alternative Methods (ECVAM) in mind, and some recommendations for action have been made at the end of the discussion section. The first section of the review describes the present requirements within the European Union for the ecotoxicity testing of industrial chemicals in general, and for pesticides in particular, and the very limited documentation of the tests that are actually carried out. The next four sections describe the many different assays and systems used to evaluate the harmful effects of chemicals on free-living organisms and natural populations, and the extent to which they might be suitable alternatives to vertebrate toxicity tests that cause suffering. Attention is drawn to certain assays and strategies that can already be used as satisfactory alternatives, and thus provide the basis for short-term change. Included here are nondestructive assays on vertebrates which are available for certain types of chemicals, and which provide a direct and relatively uncomplicated approach to the problem. Other approaches are described which still require development, but hold considerable promise in the longer term. The growth of knowledge in the broad field of biochemical toxicology and the development of related technologies should lead to the development of better and more-sophisticated alternatives in the future. In vitro assays employing vertebrate cell systems are of particular interest here. The last section of the review deals with conclusions and recommendations. The recommendations are made with a view to the activities and responsibilities of ECVAM.