Phthalate diesters are high-production-volume chemicals that have been widely used in the manufacturing and processing of plastics for more than 80 years. Recently, they have been included in the priority lists of dangerous substances in most of the industrialized countries. Ingestion is considered the major route of exposure to phthalates, either by consuming contaminated food, accidental ingestion of contaminated dust and soil, or licking of products in which they are contained. Once in the human body, phthalates are hydrolyzed to their corresponding monoesters and further oxidized or conjugated into glucuronide complexes and, finally, excreted. Wastewater-based epidemiology (WBE) is a complementary approach to human biomonitoring to estimate the level of exposure to a substance through the analysis of its metabolic residues in urban wastewater, considering that raw wastewater is a highly diluted urine sample representing an entire community. The objectives of this study were to analyze the metabolites of 6 phthalate diesters in wastewaters from different locations in Spain and to assess the exposure to phthalate diesters in the investigated cities. Raw wastewater samples from 17 wastewater treatment plants, serving a total population of ca. 6 million inhabitants (13% of the Spanish population), were analyzed. The results show that the highest population-weighted exposure loads were obtained for diethyl phthalate, followed by dimethyl phthalate and the isomers di-i-butyl phthalate and di-n-butyl phthalate.

The authors acknowledge support by Xunta de Galicia (refs. ED431C2017/36 and IGM postdoctoral contract, Plan Galego I2C-Modalidade B, ED481D 2017/003), the Spanish Research Agency-AEI (ref. CTM2016-81935-REDT/AEI and CTM2017-84763-C3-R-2) and FEDER/ERDF

Resumen del trabajo presentado en el SETAC Europe 30th Annual Meeting, celebrado en modalidad virtual del 3 al 7 de mayo de 2020.