Spatial and Temporal Variability in Pesticide Exposure Downstream of a Heavily Irrigated Cropping Area: Application of Different Monitoring Techniques

• DOI: 10.1021/acs.jafc.5b04710
• Publication Date: 2016-01-12T04:48:53Z
• Authors: Dominique O’Brien; Stephen Lewis; Aaron Davis; Christie Gallen; Rachael Smith; Ryan Turner; Michael Warne; Scott Turner; Stewart Caswell; Jochen F. Mueller; Jon Brodie
• Keywords: Metolachlor; Pesticide application; Environmental Monitoring

Pesticide exposure threatens many freshwater and estuarine ecosystems around the world. This study examined temporal spatial trends of pesticide concentrations in a waterway within an agriculturally developed dry-tropics catchment using combination grab passive sampling methods over continuous two-year monitoring program. A total 43 residues were detected with 7 pesticides exceeding ecologically relevant water quality guidelines/trigger values during period 4 (ametryn, atrazine, diuron, metolachlor) these guidelines for several months. The presence concentration stream coincided seasonal variability rainfall, harvest timing/cropping cycle, management changes. approach used demonstrates that application complementary techniques (both methods) was effective establishing usage patterns upstream locations where data are unavailable.