Vol.:(0123456789) 1 3 Environmental Earth Sciences (2019) 78:569 https://doi.org/10.1007/s12665-019-8579-3 ORIGINAL ARTICLE Levels of organochlorine pesticides in soils, mesofauna and streamwater from an agricultural watershed in Argentina Leonardo Lupi 1  · Francisco Bedmar 2  · Daniel Alberto Wunderlin 3  · Karina Silvia Beatriz Miglioranza 1 Received: 27 October 2018 / Accepted: 7 September 2019 © Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract Pesticides are usually used in modern agriculture; however, their of-site migration and detrimental efects on terrestrial biota and nearby surface water environment are of great concern. Organochlorine pesticides (OCPs) can be found in difer- ent environmental matrices due to their persistence, representing a persistent pollution source. Soil (0–35 cm), terrestrial organisms (micro- and macro-invertebrates) and stream water samples were analysed to assess OCPs’ uptake by terrestrial invertebrates and OCPs’ levels in their surrounding environment. The study area involved agricultural plots from the Pampas area (Argentina) and the sampling was carried out during summer coincident with the pesticides application period. Although OCPs 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 fooding event, and a consequent transport of legacy pesticides adsorbed to soils particles from neighbor agricultural areas. The OCPs were highly bioaccumulated in soil mesofauna (acari and collembolans: 260 μg g −1 ); therefore the high sensitivity to external impact combined with their importance for ecosystem functions make soil mesofauna extremely valuable for monitoring programmes. In the aquatic environment, high endosulfan concentrations (227 ng L −1 ) were detected in stream water, being above the maximum limit for aquatic life protection. The diferent compositions of DDT, HCH, chlordane and endosulfan in all matrixes indicated that the residues of most compounds would be originated from historical application, and the imple- mentation of long OCPs monitoring studies is highly recommended. As a whole, this study provides frst results of OCPs levels in mesofauna of a typical intensive agricultural area from Argentina, and highlights the importance of soil mesofauna as a target group to understand the OCP migration process through the animal food chain. Keywords Invertebrates · Soil pollution · Endosulfan · Forbidden pesticides Introduction Extensive agricultural practices have been associated with the use of large quantities of pesticides in Argentina. Although organochlorine pesticides (OCPs) are banned on a worldwide scale, they have been applied to crops for many years, and their residues constitute a current source of pesticides (Breivik et al. 2004). OCPs belong to persis- tent organic pollutants (POPs), which are, most of them, regulated by the Stockholm Convention (UNEP 2001). These compounds, such as DDTs, endosulfans, HCHs, hep- tachlors, drins and chlordanes, are highly toxic, persistent, volatile, lipophilic and show adverse efects on humans and ecosystems. OCPs have been widely used for extensive and intensive agriculture in the region. In addition, endosulfan has been used as an insecticide for crop protection in South America and it was banned in July 2013 in Argentina (UNEP Electronic supplementary material The online version of this article (https://doi.org/10.1007/s12665-019-8579-3) contains supplementary material, which is available to authorized users. * Karina Silvia Beatriz Miglioranza kmiglior@mdp.edu.ar 1 Laboratorio de Ecotoxicología y Contaminación Ambiental, Facultad de Ciencias Exactas y Naturales, Instituto de Investigaciones Marinas y Costeras (IIMyC), Universidad Nacional de Mar del Plata (UNMdP), Consejo Nacional de Investigaciones Científcas y Técnicas (CONICET), D. Funes 3350, 7600 Mar del Plata, Argentina 2 Departamento de Producción Vegetal, Suelos e Ingeniería Rural, Facultad de Ciencias Agrarias, UNMdP, Ruta Nacional 226, Km 73, 5, 7620 Balcarce, Buenos Aires, Argentina 3 CONICET and Dpto. Química Orgánica, Facultad Ciencias Químicas, ICYTAC: Instituto de Ciencia y Tecnología de Alimentos Córdoba, Universidad Nacional de Córdoba. Ciudad Universitaria, 5000 Córdoba, Argentina