Chemical contamination from point source discharges in developed (resource-rich) countries has been widely regulated and studied for decades; however, diffuse sources are largely unregulated and widespread. In the European Union, large dischargers report releases of some chemicals; yet, little is known of total emissions (point and diffuse) and their relative significance. We estimated copper loadings from all significant sources including industry, sewage treatment plants, surface runoff (from traffic, architecture and atmospheric deposition), septic tanks, agriculture, mariculture, marine transport (antifoulant leaching), and natural processes. A combination of European datasets, literature and industry data were utilised to generate export coefficients. These were then multiplied by activity rates to derive loads. A total of around 8 kilotons of copper per annum (ktpa) is estimated to enter freshwaters in the European Union and another 3.5 ktpa enters transitional and coastal waters. The main inputs to freshwater are natural processes (3.7 ktpa), agriculture (1.8 ktpa) and runoff (1.8 ktpa). Agricultural emissions are dominated by copper-based plant protection products and farmyard manure. Urban runoff is influenced by copper use in architecture and by vehicle brake linings. Antifoulant leaching from boats (3.2 ktpa) dominates saline water loads of copper. It is noteworthy that most of the emissions originate from a limited number of copper uses where environmental exposure and pathways exist, compared with the bulk of copper use within electrical and electronic equipment and infrastructure that has no environmental pathway during its use. A sensitivity analysis indicated significant uncertainty in data from abandoned mines and urban runoff load estimates. This study provided for the first time a methodology and comprehensive metal load apportionment to European aquatic systems, identifying data gaps and uncertainties which may be refined over time. Source apportionments using this methodology can inform more cost-effective environmental risk assessment and management. This article is protected by copyright. All rights reserved. © 2022 SETAC.
Authors: S Comber, G Deviller, I Wilson, A Peters, G Merrington, P Borrelli, S Baken
; Full Source: Integrated environmental assessment and management 2022 Oct 14. doi: 10.1002/ieam.4700.