Assessment of phthalic acid esters (PAEs) and pharmaceutical compounds (carbamazepine, diclofenac, ibuprofen, and naproxen) in waters of the Atoyac River basin, Puebla-Tlaxcala, Mexico.

Abstract

The Atoyac River basin has a critical state of contamination, generated, to a large extent, by the discharge of wastewater without prior treatment from municipal and industrial sources. In the states of Puebla and Tlaxcala there is a high percentage of land use for agricultural development, in which water from the Atoyac River is commonly used for crop irrigation. The characterization of occurrence of contaminating compounds allows to understand the possible risk of exposure that farmers, as well as other organisms, may have. Therefore, the determination of occurrence of 9 phthalates and 4 pharmaceutical compounds (DIC, IBF, NP, and CBZ) was carried out in the system comprised by the Zahuapan River, the Atoyac River and the Valsequillo reservoir. The measured concentration levels exceed the permissible limits in environmental regulations such as the US-EPA and they are comparable to concentrations measured in other highly polluted rivers around the world. Distribution and correlation analysis show that the areas of greatest contamination are associated with the presence of industrial parks, which use these compounds in their manufacturing processes. In addition, the toxicological study reports a medium and high risk to aquatic species due to exposure to these compounds.