Spatial and temporal evaluations of estrogenic activity in tap water served by a water plant in Wuhan, China

This study aimed to evaluate the spatial and temporal characteristics of estrogenic activities in tap water served by a water plant in Wuhan, China. Tap water samples were monthly collected from the three sampling sites with different distances of distribution network from the plant during April 2010–March 2011: Min (less than 0.1 km), Mid (approximately 4 km) and Max (approximately 8 km). Estrogenic activities of solid phase-extracted tap waters were measured by using recombinant yeast assay incorporated with and without exogenous metabolic activation system (rat liver S9 fractions) and expressed as 17β-estradiol equivalents (EEQ). Pro-estrogenic and estrogenic activity in tap water ranged from 151.4 to 1395.6 pg EEQ/L and 35.2 to 1511 pg EEQ/L, respectively. Average pro-estrogenic activity (680.3 pg EEQ/L) was significantly higher than estrogenic activity (412.8 pg EEQ/L) throughout the whole year. The pro-estrogenic activity significantly increased with the extending of distribution network, and was also statistically correlated with water temperature and pH. However, pro-estrogenic and estrogenic activity was not altered across four seasons. Our results suggest that the pro-estrogenic and estrogenic chemicals are present in tap water served by the water plant.

► The spatial and temporal characteristics of estrogenic activities in tap water were evaluated.
► Pro-estrogenic activity was significantly higher than estrogenic activity.
► Significant spatial variability occurred in the pro-estrogenic activity.
► The pro-estrogenic and estrogenic chemicals are present in tap water served by the water plant.