Reducing Neonicotinoids in Aquatic Resources: Vegetative Buffer Strips impede imidaclorprid movement in Missouri agroecosystems

Neonicotinoids are a class of broad-spectrum systemic insecticides frequently used in agroecosystems to control root and leaf eating pests. The widespread use and environmental persistence of neonicotinoids in the U.S. and globally has resulted in surface water contamination and build-up of neonicotinoids within other environmental sectors, such as soils and wetlands. Deleterious effects of neonicotinoids on non-target insects and wildlife heightens the need to determine practices that reduce potential for these chemicals to reach aquatic ecosystems through subsurface connections and overland surface runoff. An understanding of neonicotinoid sorption (any removal of a compound from solution to a solid phase) and transport in soil is critical for determining and mitigating environmental risks associated with this class of insecticides. We evaluated whether conservation practices, such as vegetated buffer strips (VBS), could reduce neonicotinoid entry into surface waters and aquatic ecosystems. One of the most commonly used neonicotinoids is imidacloprid (ICD) which first entered the United States markets in 1994. This Science Note focuses on differences in the sorption and transport of imidacloprid within soils collected from grass VBS, riparian VBS, and agricultural fields planted to corn/soybean.