PERSONAL DE APOYO
FANELLI Silvia Laura
congresos y reuniones científicas
Insecticide Concentrations In Streams Of Soy Production Regions In South America
HUNT L; BONETTO C; RESS V ; FORSIN BUSS D; FANELLI S.L.; MARROCHI N; LYDY, M.
Congreso; SFS Annual Meeting 2015. "Our freshwater futures". Society for Freshwater Science; 2015
Society for Freshwater Science
Concentrations of 17 insecticides were measured in sediments collected from 48 streams in intensive soy production regions of South America (Argentina in 2011-2014, Paraguay and Brazil in 2013) during peak application periods. Although environmental regulations are quite different in each country, commonly used insecticides were detected at high frequencies in all regions. Maximum concentrations (and detection frequencies) for each sampling event ranged from: 1.2?7.4 ng/g dw chlorpyrifos (56-100%); 1.2?7.4 ng/g dw cypermethrin (20-100%); 0.42?16.6 ng/g dw lambda-cyhalothrin (60-100%); and 0.49?2.1 ng/g dw endosulfan (13-100%). Other pyrethroids were detected less frequently. Banned organochlorines were most frequently detected in Brazil. In all countries, cypermethrin and/or lambda-cyhalothrin toxic units (TUs) based on Hyalella azteca LC50s were occasionally >0.5 (indicating likely acute toxicity), while TUs for other insecticides were <0.5. There was a negative relationship between buffer width and TUs, and 83% of sites with average total TU>0.5 had buffers of <20m. While Brazil and Paraguay require forested stream buffers, there are no such regulations in the Argentine pampas where buffer widths were smaller