In this post, Sebastian Stehle informs about their recent paper on shortcomings and failures of the regulatory EU pesticide risk assessment procedures.

Satellite image of surface waters located in a typical EU agricultural landscape (Copyright Google, Digital Globe, 2014)

Pesticides with an annual value of 11 billion Euros are applied each year to approximately 115 million hectares of agricultural land in the European Union. This widespread and intentional release of highly biologically active chemicals poses threats to non-target aquatic and terrestrial ecosystems; highly elaborated environmental regulatory risk assessment schemes conducted prior to pesticide authorization should thus ensure that agricultural pesticide use does not lead to unacceptable adverse effects in the European environment. However, no field data-based evaluation of the risk assessment outcome, i.e., the regulatory acceptable concentrations (RACs), and therefore of the overall protectiveness of EU pesticide regulations exists. We therefore conducted a comprehensive meta-analysis using peer-reviewed literature on agricultural insecticide concentrations in EU surface waters and evaluated associated risks using the RACs derived from official European pesticide registration documents.

The results of our study show that 44.7% of the 1,566 insecticide concentrations detected in EU surface waters exceeded respective RACs. It follows that current EU pesticide regulations fail to protect EU surface waters and that insecticides denote a substantial threat to the freshwater biodiversity (see also our previous post on the EcotoxBlog for more information on insecticide effects on the aquatic biodiversity). Based on meta-analysis techniques and linear modeling, we prove, for example, (i) that RAC exceedances are significantly higher for newer insecticide classes and increase over time despite the enforcement of more stringent EU pesticide legislations; (ii) that the RAC exceedances of currently authorized compounds are comparable to those of non-authorized compounds (which have been withdrawn from the market due to environmental concerns); (iii) the contradictory fact that the most toxic compounds are authorized using least conservative (higher-tier) RACs; and (iv) that insecticide compounds currently not considered as priority substances by the European Water Framework Directive pose higher risks compared to those classified as priority substances. Moreover, we identified highest RAC exceedances for surface waters and application scenarios that are specifically considered in the regulatory risk assessment schemes; this finding seriously questions the field relevance of the entire EU authorization procedure.

Overall, this study shows that current EU pesticide legislations, including the entire regulatory risk assessment schemes, do not protect the aquatic environment. This finding may trigger far-reaching concerns because the EU regulatory evaluation process for pesticides and associated EU surface water legislations are widely perceived to be highly elaborated and protective. However, based on our results we conclude that critical revisions of the EU pesticide regulations and effective mitigation measures are urgently needed to substantially reduce the environmental risks arising from agricultural insecticide use.

The article “Pesticide Authorization in the EU – Environment Unprotected?” was authored by Sebastian Stehle and Ralf Schulz and published in Environmental Science and Pollution Research.