Advancing Surface Water Pesticide Exposure Assessments for Ecosystem Protection

Highlights Crop protection and pest management programs continue to be integral for modern food production. Potential ecological impacts of pesticides must be assessed, and key mitigation practices adopted. Efforts are needed to advance surface water pesticide exposure assessments from field to landscape scales. Ensuring effective pesticide mitigation practices requires quantifying dynamic site-specific characteristics. Ecological assessments must improve prediction of adverse population and community-level outcomes. Abstract. As the global food demand increases, the use of pesticides will continue to increase with significant growth in low- and middle-income countries. Agricultural systems in which pesticides are used are complex with significant and often unknown biological, human, and physical-chemical interactions. These interactions include climate and hydrology, soil type, selection and use of best management practices, chemical fate and transport, application technology, and land use socioeconomics. The objective of this review article is to highlight key research opportunities identified from recent special meetings and workshops on advancing pesticide exposure assessments and mitigation. Research is needed in using advanced analytics and forensics to better understand the distribution of pesticides in the environment through novel monitoring and detection. Higher-tier modeling approaches can help inform monitoring a priori to better characterize pesticide distributions in the environment. Current pesticide exposure assessments are largely focused on the field or watershed scale, but advancements are needed to move toward landscape-scale analyses capable of analyzing for interacting ecosystems. Assessing the effects of complex, low-dose chemical mixtures on non-target aquatic organisms must advance with new quantitative high-throughput experimental methods focused on identifying interactions and not just additive effects. Field mitigation measures are currently considered as part of the pesticide exposure and risk assessment process using qualitative, fixed-efficiency type approaches, but we specifically call for the use of existing quantitative tools moving forward. These mechanistic modeling and simulation tools can capture the inherent complexity within an agroecological system. There is a need for risk assessment to be more predictive of population and community-level impacts as part of environmentally relevant scenarios. Finally, it is imperative that professional societies take a more proactive role in promoting the transdisciplinary collaboration of biological and agricultural engineers with other disciplines contributing to advances in ecological risk assessment.