Levels of organochlorine pesticides in soils, mesofauna and streamwater from an agricultural watershed in Argentina

LUPI LEONARDO; BEDMAR FRANCISCO; WUNDERLIN DANIEL A.; MIGLIORANZA KARINA SILVIA BEATRIZ

Environmental Earth Sciences

Springer

Lugar: Berlin Heidelberg; Año: 2019

1866-6280

Pesticides are usually used in modern agriculture; however, their of-site migration and detrimental efects on terrestrialbiota and nearby surface water environment are of great concern. Organochlorine pesticides (OCPs) can be found in diferent environmental matrices due to their persistence, representing a persistent pollution source. Soil (0?35 cm), terrestrialorganisms (micro- and macro-invertebrates) and stream water samples were analysed to assess OCPs? uptake by terrestrialinvertebrates and OCPs? levels in their surrounding environment. The study area involved agricultural plots from the Pampasarea (Argentina) and the sampling was carried out during summer coincident with the pesticides application period. AlthoughOCPs have been banned in Argentina, the concentration of OCPs in soils increased during the pesticide application period(2.8 ng g−1) in comparison with the pre-application period (0.3 ng g−1). It would be probably as a result of a looding event,and a consequent transport of legacy pesticides adsorbed to soils particles from neighbor agricultural areas. The OCPs werehighly bioaccumulated in soil mesofauna (acari and collembolans: 260 μg g−1); therefore the high sensitivity to externalimpact combined with their importance for ecosystem functions make soil mesofauna extremely valuable for monitoringprogrammes. In the aquatic environment, high endosulfan concentrations (227 ng L−1) were detected in stream water, beingabove the maximum limit for aquatic life protection. The diferent compositions of DDT, HCH, chlordane and endosulfan inall matrixes indicated that the residues of most compounds would be originated from historical application, and the implementation of long OCPs monitoring studies is highly recommended. As a whole, this study provides irst results of OCPslevels in mesofauna of a typical intensive agricultural area from Argentina, and highlights the importance of soil mesofaunaas a target group to understand the OCP migration process through the animal food chain.