Ecological Risk Assessment of Five Endocrine-Disrupting Compounds in Wastewater Treatment Plants from Monterrey, Mexico
Abstract The potential ecological risk of five residual endocrine-disrupting compounds (EDCs) in four wastewater treatment plants (WWTPs) was studied. The wastewater samples were collected in WWTPs of the Metropolitan Area of Monterrey, Mexico (designed as Monterrey City hereinafter) and 17β-estradiol (E2), 17α-ethinylestradiol (EE2), bisphenol A (BPA), 4-nonylphenol (4NP), and 4-tert-octylphenol (4TOP) were studied by SPE/GC-MS method. Results showed that all EDCs are widely distributed in WWTPs, finding high concentrations of BPA (450 ng/L) and EE2 (407.5 ng/L) in influents, while EE2 and 4TOP were the most abundant in effluents at levels from 1.6–26.8 ng/L (EE2) and < LOQ – 5.0 ng/L (4TOP), which corroborate that the wastewater discharges represent critical sources of EDCs to the aquatic environments. The potential ecological risk of residual EDCs was evaluated through risk quotients (RQs), and results indicated that the effluents of the WWTPs represent a high risk to exposed aquatic species, mainly due to the effect of residual estrogens E2 and EE2 which were considered as the most hazardous compounds among the studied EDCs, with RQ values up to 49.1 and 1165.2, respectively.