Occurrence and risk evaluation of endocrine disrupting chemicals in wastewater and surface water of Lahore, Pakistan

The current study highlights the occurrence, spatial distribution and risk assessment of sixteen endocrine disrupting chemicals (EDCs) including their transformation products (TPs) in the wastewater and surface water of Lahore, Pakistan. The parent EDCs include bisphenol A (BPA), triclosan (TCS), triclocarban (TCC), estrone (E1), estradiol (E2), estriol (E3), ethinylestradiol (EE2), 4- n -octylphenol (4 n -OP ), and 4- n -nonylphenol (4 n -NP). The TPs include two TPs each of BPA, TCC and estrogens along with a TP of TCS. Most EDCs showed 100% detection frequency in the wastewater with highest median concentration of 1310 ng/L for E3. In the surface water, the highest median concentration was however observed for BPA (54.6 ng/L). Spatial variations in terms of sum of concentration due to all EDCs and their TPs were observed at different sampling points which suggests contamination due to industrial sources. Risk evaluation in terms of risk quotient (RQ) and estradiol equivalent factor (EEQ) showed that most of EDCs and their TPs could pose high risk and estrogenicity to the surrounding environment. From the results of the current study, it is observed that the environment of Pakistan is deteriorating and is potential risk for endocrine disruption. It is therefore recommended to take stringent measures to make it sustainable for current as well as for future generations.