生活污水中环境雌激素的厌氧消化行为特征及环境风险评价

Behaviors and Environmental Risk Assessment of Estrogenic Endocrine Disruptors in Anaerobic Domestic Wastewater Treatment

为了研究生活污水中典型环境雌激素（estrogenic endocrine disruptors,EEDs）在上流式厌氧污泥床（upflow anaerobic sludgeblanket,UASB）和厌氧滤池（anaerobic filter,AF）中的行为特征和去除机制,采用固相萃取（SPE）-LC/MS/MS分析方法,测定了9种EEDs的浓度和污泥吸附量,利用壬基酚当量（nonylphenol equivalent quantity,NEQ）进行了环境风险评价.结果表明,厌氧污泥对各EEDs的吸附能力与该物质的lgKow和分子长度相关;UASB对雌二醇（E2）和大豆苷元的去除率分别达83.2%和90.4%,AF对染料木素的去除率达81.6%;9种EEDs在UASB和AF中的污泥-水分配系数（Kp）分别为0.15-23.3和0.05-159.67;综合分析去除率和Kp值数据,揭示了生物降解是大豆苷元、染料木素、双酚A（BPA）和雌三醇（E3）的主要去除途径;出水的NEQ均小于美国EPA的壬基酚水质标准（28μg.L-1,小时平均浓度标准）,表明EEDs经厌氧处理后其环境风险有所降低.

Solid phase extraction-LC/MS/MS detection method was applied to study the concentrations and sludge adsorptions of nine estrogenic endocrine disruptors （EEDs） in an upflow anaerobic sludge blanket （UASB） and an anaerobic filter （AF）. Nonylphenol equivalent quantity （NEQ） was calculated to evaluate the environmental risk of the EEDs. The results show anaerobic sludge adsorption has positive correlation with lgKow and molecular length of EEDs. 17β-estradiol （E2） and daidzein reached 83.2% and 90.4% removal rates in UASB, respectively. Genistein in AF is removed more than 80%. The sludge-water partition coefficient（ Kp ） of nine EEDs ranged from 0.15-23.3 in UASB and 0.05-159.67 in AF. Biodegradation could be the main elimination pathway for daidzein, genistein, bisphenol A and estriol, by combining analysis of removal data and Kp values. Environmental risk of EEDs was reduced after anaerobic treatment, as effluent NEQ was below the US EPA nonylphenol criteria （28 μg·L^-1 , hour average concentration standard）.