Analysis of the Ecetoc Aquatic Toxicity (EAT) database I — General introduction

In assessing the environmental risk of a chemical it is necessary to predict safe levels in the environment, but this requires extrapolation from relatively small databases. To improve understanding of the use of existing data for such extrapolations, the European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) established a Task Force to assemble a high-quality database on aquatic toxicity from published papers. The database contains over 2200 records of effects of about 360 substances on 121 aquatic species. Computer programs were developed to enter, search for, retrieve and analyse the data. Output consisted of simple counts, frequency distributions and regression analyses by which (for example) comparisons of different life-stages, species-sensitivity and acute:chronic ratios, and application of QSARs could be examined for use in risk assessment. This paper describes the content of the database, the methods of analysis and gives a brief comparison of acute: chronic ratios: four subsequent papers describe the results.