Detection of current- use pesticides in Argentinian surface waters using polar organic chemical integrative samplers (POCIS)

CORCORAN, SHAWNA; LUKASZEWICZ, GERMÁN; METCALFE, CHRIS; AMÉ, M. VALERIA; ITURBURU, GASTÓN; MENONE, MIRTA L; GARANZINI, DANIELA

Santos

Congreso; SETAC Latin America 12th Biennial Meeting; 2017

SETAC LA

There have been few studies on the occurrence of current-use pesticides (CUP) in Argentina. Therefore, the objective of this work was to evaluate whether pesticide contamination of the freshwater resources in Argentina is currently occurring by monitoring two selected water bodies impacted by agriculture using passive sampling techniques. Polar Organic Chemical Integrative Samplers (POCIS) were deployed in the Ctalamochita River (Córdoba province) and in Brava Lake (Buenos Aires province) during December, 2014 and February, 2015. POCIS provide an estimate of the time weighted average (TWA) concentration of target chemicals in water. The results revealed that the fungicides, tebuconazole, carbendazim and azoxystrobin, and the herbicides, atrazine, dicamba and 2,4-D were detected at one or more sampling locations in each watershed. In Brava Lake, the highest estimated TWA concentration was for atrazine in the effluent stream (Tajamar creek) monitored during December 2014. It was not unexpected to find atrazine, since this herbicide is a widely detected CUP in surface waters. The estimated TWA concentration of atrazine was significantly lower in the influent stream at El Peligro and this compound was not detected at the same location during February, 2015. The herbicides, dicamba and 2, 4-D showed a similar trend with atrazine. The occurrence of the fungicides generally followed the same trend as the herbicides, with higher concentrations in the effluent stream compared to the influent stream. In POCIS deployed in Ctalamochita river, the herbicides dicamba and 2,4-D were present at the highest estimated TWA concentrations, mainly at Puente los Potreros station, while the levels of atrazine remained fairly constant across all locations. The estimated TWA concentrations for the fungicides azoxystrobin, carbendazim and tebuconazole were relatively low in comparison to the herbicides. Other fungicides used in pharmaceuticals and personal care products (i.e. ketoconazole, climbazole) were not detected in POCIS from La Brava, indicating that there were no nearby sources of municipal wastewater. However, traces of the pharmaceutical, fluconazole were detected in POCIS in amounts