Ågerstrand et al. Environmental Sciences Europe 2011, 23:17 RESEARCH Open Access Comparison of four different methods for reliability evaluation of ecotoxicity data: a case study of non-standard test data used in environmental risk assessments of pharmaceutical substances Marlene Ågerstrand1*, Magnus Breitholtz2 and Christina Rudén1 Abstract Background: Standard test data are still preferred and recommended for regulatory environmental risk assessments of pharmaceuticals even though data generated by non-standard tests could improve the scientific basis of risk assessments by providing relevant and more sensitive endpoints. The aim of this study was to investigate if non-standard ecotoxicity data can be evaluated systematically in risk assessments of pharmaceuticals. This. | Ãgerstrand et al. Environmental Sciences Europe 2011 23 17 http content 23 1 17 o Environmental Sciences Europe a SpringerOpen Journal RESEARCH Open Access Comparison of four different methods for reliability evaluation of ecotoxicity data a case study of non-standard test data used in environmental risk assessments of pharmaceutical substances Marlene Agerstrand1 Magnus Breitholtz2 and Christina Rudén1 Abstract Background Standard test data are still preferred and recommended for regulatory environmental risk assessments of pharmaceuticals even though data generated by non-standard tests could improve the scientific basis of risk assessments by providing relevant and more sensitive endpoints. The aim of this study was to investigate if non-standard ecotoxicity data can be evaluated systematically in risk assessments of pharmaceuticals. This has been done by evaluating the usefulness of four reliability evaluation methods and by investigating whether recently published non-standard ecotoxicity studies from the open scientific literature fulfill the criteria that these methods propose. Results The same test data were evaluated differently by the four methods in seven out of nine cases. The selected non-standard test data were considered reliable acceptable in only 14 out of 36 cases. Conclusions The four evaluation methods differ in scope user friendliness and how criteria are weighted and summarized. This affected the outcome of the data evaluation. The results suggest that there is room for improvements in how data are reported in the open scientific literature. Reliability evaluation criteria could be used as a checklist to ensure that all important aspects are reported and thereby increasing the possibility that the data could be used for regulatory risk assessment. Background Environmental risk assessment of pharmaceuticals In 2006 the European Medicines Agency EMA decided that all new marketing authorisation applications for human .