Double the trouble: High levels of both synthetic pesticides and copper in vineyard soils

The widespread use of pesticides raises concerns about their impact on soil health. Although vineyard soils are strongly exposed to both, synthetic pesticides and copper, a systematic, detailed, and joint assessment has been lacking. In our study we measured copper and 146 synthetic pesticides in 62 organic and conventionally managed vineyards at high sensitivity. Up to 60 different pesticides were detected per vineyard. Total pesticide concentrations were almost 13 times higher under conventional compared to organic management. Total copper contamination was high overall with a mean of 371 mg/kg, and no difference between organic and conventional vineyards was found. Pesticide levels declined with increasing years since conversion to organic farming. However, even after 20 years of organic farming, up to 32 pesticides could still be found. Several pesticides showed far higher persistence in soil than expected based on their half-lives. Compared to other land uses, pesticide and copper contamination was clearly higher. Our risk assessment revealed that 50 % of the studied vineyard soils reached pesticide and copper concentrations potentially harmful to soil organisms and only 10 % of vineyard soils were not at risk from either of them. This underscores the urgent need for further research and policy intervention to address these environmental risks.