Widespread contamination of soils and vegetation with current use pesticide residues along altitudinal gradients in a European Alpine valley

Pesticides are transferred outside of cropland and can affect animals and plants. Here we investigated the distribution of 97 current use pesticides in soil and vegetation as central exposure matrices of insects. Sampling was conducted on 53 sites along eleven altitudinal transects in the Vinschgau valley (South Tyrol, Italy), in Europe’s largest apple growing area. A total of 27 pesticides (10 insecticides, 11 fungicides and 6 herbicides) were detected, originating mostly from apple orchards. Residue numbers and concentrations decreased with altitude and distance to orchards, but were even detected at the highest sites. Predictive, detection-based mapping indicates that pesticide mixtures can occur anywhere from the valley floor to mountain peaks. This study demonstrates widespread pesticide contamination of Alpine environments, creating contaminated landscapes. As residue mixtures have been detected in remote alpine ecosystems and conservation areas, we call for a reduction of pesticide use to prevent further contamination and loss of biodiversity.