Assessment of emerging endocrine-disrupting compounds, namely estrone, 17-beta-estradiol, estriol, and 17-alpha-ethinyl estradiol, in the drinking water piping network of Tehran

In recent decades, micro-pollutants like estrogen hormones have been considered due to adverse health effects on humans and the environment despite a very low concentration of 0.1-20 ng/L. In the present study, drinking water was sampled from the six areas of Tehran in summer (August 2020), autumn (November 2020), winter (February 2021), and spring (May 2021) to evaluate natural and synthetic estrogen hormones (estrone (E1), 17-beta-estradiol (E2), estriol (E3), and 17-alpha-ethinyl estradiol (EE2)). The samples were transferred to the laboratory and used the solid-phase extraction (SPE) method to extract the hormones, and were examined the type and amount of hormones by gas chromatography-mass spectrometry. According to the results, the highest concentrations were related to E1 and E2 compounds by 1.96 and 2.13 ng/L, respectively, in summer and autumn (device detection limit = 0.5 ng/L). In addition, concentrations of compounds E1 and E2 were lower than the detection limit in spring and winter in all samples, and compounds E3 and EE2 were not identified in any samples and season. Commonly, the concentration of steroid hormones increased in the dry seasons (summer and autumn), while in the spring and winter concentration it reached less than the device detection limit because of rainfall.