Assessing the Estrogenic Activity of EDCs and Human Risks of Groundwater after Ozonation and Chlorination

Endocrine Disrupting Chemicals (EDCs) in groundwater could result in severe risks to human health. Therefore, in the present study, ozone (O-3) and chlorine were applied to remove the estrogenicity of Bisphenol-A (BPA), 4-Nonylphenol (4-NP) and Triclosan (TCS) in groundwater. Bioluminescent Yeast Estrogen Screen and Gas Chromatography Mass Spectrometry (BLYES-GC/MS) demonstrated that there is no directly proportional relationship between concentration and estrogenicity. Human Risk Assessment (HRA) was conducted, considering the concentration of EDCs, their estrogenicity and the by-products formed. Estrogenicity decreased by 98.7, 79.3 and 97.0% (ozone) and 86.2, 94.3 and 97.8% (chlorine) for BPA, 4-NP AND TCS, respectively. The individual Hazard Quotient (HQ<1), cumulative risk Hazard Index (HI) and intake 17-estradiol equivalents (EEQ) (mu g day(-1)) indicate that ozone and chlorine treatment, including any by-products formed, do not result in estrogenicity with associated HR.