title: Anti-estrogenic activity formation potential assessment and precursor analysis in reclaimed water during chlorination.
abstract: Chlorination was reported to increase the anti-estrogenic activity in reclaimed water from domestic wastewater treatment plants, which may add to the risk of reclaimed water reuse. In order to assess the anti-estrogenic disinfection by-product (DBP) precursors, the anti-estrogenic activity formation potential (AEAFP) during chlorination was studied. Firstly, the conditions for the experimental measurement of AEAFP were determined. A 24-h chlorination experiment was applied for AEAFP measurement. After chlorination, dechlorination using reductive reagents led to significant loss of anti-estrogenic activity formation. In addition, as the presence of ammonia nitrogen and other major chlorine consumers would result in lower anti-estrogenic activity formation, a basic chlorine dose of 3× DOC (mg-Cl2 L(-1)) was adequate for completely transforming the anti-estrogenic DBP precursors while an extra chlorine dose of 8× ammonia-nitrogen + 5× nitrite-nitrogen (mg-Cl2 L(-1)) should be added when there was a high level of ammonia nitrogen and nitrite nitrogen in the reclaimed water. Therefore, 24-h chlorination without dechlorination or using only non-reductive quenching reagents (e.g. ammonium) for dechlorination and a total chlorine dose of 3× DOC + 8× ammonia nitrogen + 5× nitrite nitrogen (mg-Cl2 L(-1)) should be fulfilled for the AEAFP measurement. Moreover, the AEAFP (0.2-2.1 mg-TAM L(-1)) of the reclaimed water samples (n = 20) were further analyzed. The AEAFP was highly correlated to UV254 and the fluorescence volume in excitation emission matrix fluorescence spectrum which can be used as surrogates to indicate the level of the AEAFP and assess the precursors in reclaimed water.
authors.affiliation: Environmental Simulation and Pollution Control State Key Joint Laboratory, and State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), School of Environment, Tsinghua University, Beijing 100084, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Tang
authors.forename: Qian Yuan
authors.initials: QY
authors.lastname: Wu
authors.forename: Ye
authors.initials: Y
authors.lastname: Du
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Hong Ying
authors.initials: HY
authors.lastname: Hu
mesh_terms: D020847:Estrogen Receptor Modulators / Q000737:chemistry*; D054879:Halogenation; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry*
chemical_list: D020847:Estrogen Receptor Modulators; D014867:Water
keywords: Anti-estrogenic activity formation potential; Chlorination; Precursor; Reclaimed water