Occurrence of pesticides in drinking water and groundwater in the Azuero Peninsula

Abstract

Modern agriculture relies on the use of pesticides to increase food production and meet the needs of a growing population. However, inappropriate use of pesticides can have a significant impact on aquatic ecosystems, as they can enter surface waters or leach into groundwater. This poses a risk to public health since these compounds are persistent and mobile in water sources used for drinking water production. In this context, an investigation was carried out in the Azuero peninsula, to analyze samples of drinking water and groundwater used for consumption. Samples were collected during the rainy season in September 2022 and the dry season in April 2023. EPA Method 525.2 was carried out to detect 17 pesticides using solid phase extraction (SPE) and gas chromatography coupled with mass spectrometry (GC-MS). The results indicated the presence of pendimethalin, atrazine, and its metabolite atrazine-desethyl at low concentrations in drinking water samples in the districts of La Villa de Los Santos and Parita, as well as in groundwater in Santa María. However, the concentrations detected were below the permissible limits according to Panamanian regulations (Technical Regulation DGNTI - COPANIT 21-2019) for drinking water.