Water quality — Guidance on statistical interpretation of ecotoxicity data

ISO/TS 20281:2006 offers guidance on statistical methods used for the analysis of data of standardized ecotoxicity tests. It focuses on statistical methods for obtaining statistical estimates of parameters. The methods described are intended to cover laboratory ecotoxicity tests (aquatic, sediment and/or terrestrial tests), and may also be relevant for other toxicity tests.

Hypothesis testing, concentration-response modelling and biology-based modelling are discussed for the different data types (quantal, continuous and discrete data, corresponding to mortality, growth or reproduction). In addition, some guidance on experimental design is given. Although the main focus is on giving assistance to the experimentalist, a secondary aim is to help those who are responsible for evaluating toxicity tests. Finally, ISO/TS 20281:2006 may be helpful in developing new toxicity test guidelines by giving information on experimental design and statistical analysis issues.