Estimating the risk of groundwater contamination and environmental impact of pesticides in an agricultural basin in Argentina

Due to the increase in pesticide detection in groundwater and other environmental components, some indicators, such as the attenuation factor (AF) and the environmental impact quotient (EIQ), have been proposed to determine potential pesticide contamination. Thus, it is possible to select pest management strategies in order to minimize the risk of environmental impact. The objective of this work was to evaluate the potential groundwater contamination as well as the environmental impact due to pesticide use on the main crops within the Dulce creek basin (southeast Buenos Aires Province, Argentina). In the present study, 17 herbicides, 20 fungicides and 14 insecticides were selected. According to AF values, Imazetapir and Picloram herbicides, and Clothianidin insecticide were responsible for the greatest risk of groundwater contamination. Fungicides were classified as very immobile to moderately mobile, which determined an unlikely to highly unlikely risk of contamination potential tied to them. Results showed that herbicides would pose the greatest risk of potential groundwater contamination within the studied basin, followed by insecticides and finally by fungicides. Most pesticides showed a low EIQ, but the high number of applications of some of them, particularly in potatoes, significantly increased their dangerousness. Potato was the riskiest crop due to the high use of fungicides associated with its production. These results should be useful for the decision-making of the people or institutions related to the planning of the use of environmental resources in order to promote more sustainable forms of agricultural production.