Temporal trends in pesticide pressure differ among non-target species groups but show spatially consistent patterns...

The negative impacts of pesticides on biodiversity, ecosystem functioning, and human health are broadly documented and numerous policies have been proposed to reduce their use and associated risks. A key challenge is to provide relevant metrics of pesticide use that account for toxicity variation between pesticides to inform public policy. Here, we estimated temporal and spatial trends in pesticide pressure in France between 2008 and 2022 using the total applied toxicity (TAT) measure. The TAT integrates pesticide masses and toxicity data from official environmental risk assessments toward different species groups. TATs were derived for 303 pesticides and eight species groups that represent important roles in ecosystem functioning. Temporal trends were identified, spatially mapped, and related to the crops grown locally. We found that the temporal trends in pesticide pressure differed among species groups but exhibited similar spatial patterns. Pesticide pressures increased for aquatic invertebrates, but decreased for aquatic plants, pollinators, terrestrial vertebrates, and soil organisms, whereas no change was observed for fish, terrestrial arthropods, or terrestrial plants. Pesticide pressure was strongly spatially correlated across species groups, with greater pressure in the north and west of France. These spatial patterns were primarily driven by the cultivation of beet, oilseed rape, corn, and vegetables, as well as vineyards. Overall, TAT provides an index to evaluate pesticide pressure while accounting for highly variable pesticide toxicities and is used here to identify areas in which mitigation strategies should be prioritized. Our work also highlights that recent regulatory action, such as the ban of diquat and neonicotinoids, have substantially reduced pesticide pressures for multiple organism groups.