Pervasive sublethal effects of agrochemicals on insects at environmentally relevant concentrations

Insect biomass is declining globally, likely driven by climate change and pesticide use, yet systematic studies on the effects of various chemicals remain limited. In this work, we used a chemical library of 1024 molecules—covering insecticides, herbicides, fungicides, and plant growth inhibitors—to assess the impact of sublethal pesticide doses on insects. In Drosophila melanogaster, 57% of chemicals affected larval behavior, and a higher proportion compromised long-term survivability. Exposure to sublethal doses also induced widespread changes in the phosphoproteome and changes in development and reproduction. The negative effects of agrochemicals were amplified when the temperature was increased. We observed similar behavioral changes across multiple insect species, including mosquitoes and butterflies. These findings suggest that widespread sublethal pesticide exposure can alter insect behavior and physiology, threatening long-term population survival.