Effect-Based Assessment of the Quality and Potential Presence of Hazardous Chemical Pollutants in Drinking and Potable Water in Mexico City.

Effect-based methods (EBMs) are bioanalytical tools detecting bioactivity of chemical mixtures on different toxicological end points. EBMs have become increasingly important for water quality assessment and monitoring, particularly in Europe and Australia. To date, their application has not been reported for the assessment of water in Mexico, where tap water is often not consumed as drinking water due to perceived concerns of pollution from the distribution system. In this study, a battery of EBMs was applied to assess the quality of drinking and potable water from Mexico City and surrounding states. The results were compared with international reports and proposed effect-based trigger (EBTs) values. Aryl hydrocarbon receptor bioactivity and androgen receptor (AR) inhibition were detected in tap water and household-filtered water. Estrogen receptor activity was observed in most of the samples, with the highest levels detected in water from the jug container. No bioactivities were detected for AR activity, genotoxicity, or oxidative stress. Although some of the samples were bioactive, the calculated bioanalytical equivalent concentrations (BEQs) were generally below the reported BEQs from other countries and below the proposed EBTs for drinking water. These findings indicate that the tested drinking and potable water sources in the surrounding states of Mexico City are of good quality.