A new study evaluated for the first time comprehensive global insecticide contamination data for agricultural surface waters using the legally-accepted regulatory threshold levels (RTLs) as defined during the official pesticide authorization procedures. The results are alarming: more than 40% of the water-phase samples with a detection of an insecticide concentration, exceeded respective RTLs. Concerning the exposure of sediments (i.e., deposits at the bottom of the surface water bodies), more than 80% of the insecticide concentrations exceeded RTLs, which, however, often are less binding from a regulatory perspective. Overall, the results of this study indicate that insecticides pose substantial threats to the biodiversity of global agricultural surface waters and that the current regulatory risk assessment schemes and pesticide authorzsation procedures fail to protect the aquatic environment.

Source: Insecticide contamination of global surface waters substantially higher than expected