First national-scale reconnaissance of neonicotinoid insecticides in streams across the USA

Nationwide sampling for neonicotinoid detections in the US found at least one neonicotinoid in 53% of all sites sampled, with imidacloprid detected most frequently (37%, maximum concentration 140 ng/L). Imidacloprid detections were positively related to the percentage of urban area within the basin. The level of detection for their analysis methods was 2 ng/L. Detections of neonicotinoid mixtures were common, with 26% of samples including two or more. In the urban sampling area in Georgia, imidacloprid was found in 87% of the samples.