Recital (24)

Whereas the risk from mixtures of pesticides is to some degree covered in Directive 2006/118/EC by the quality standard for total pesticides, the risk from such mixtures is not addressed in Directive 2008/105/EC. To at least partly address that cumulative risk, an EQS should therefore be set for the sum of the pesticides that are already included in the list of priority substances that are to be monitored in water, and that EQS should be taken into account when assessing chemical status. To take better account of mixture risk in the future, the Commission should consider setting standards for the sum(s) of selected pesticides, potentially based on mode of action and possibly covering more pesticides than those listed individually in Annex I to Directive 2008/105/EC, at the next review. For that reason, the sum(s) of selected pesticides by mode of action should be included in a new annex to that Directive. The Commission should also consider whether a risk-based approach could be taken to establishing an EQS for total pesticides, supported by an appropriate monitoring method. Because the generic quality standards of 0,1 μg/L and 0,5 μg/L for individual and total pesticides in groundwater specified in Annex I to Directive 2006/118/EC were established in the 1980s, and limited by the sensitivity of the analytical methods available at that time, they may not be sufficiently protective of human health or the environment. The Commission should therefore review those values at the next review of the list of pollutants in groundwater.