Behavior of Endocrine Disrupting Nonylphenol in Sewage Treatment Plant

本研究的目的是研究在干燥和潮湿的天气下，在一个联合污水处理厂（STP）和多摩河接收几个STP的污水时，怀疑具有内分泌干扰作用的烷基酚（AF）的行为。干燥条件下，4-t-丁基酚（BP）含量为0.1 ~ 0.2 μg/L， 4-t-辛基酚（OP）含量为0.2 ~ 0.4 μg/L，壬基酚（NP）含量为2.8 ~ 7.5 μg/L。大部分OP和NP被吸附在悬浮物（SS）上。污泥处理侧流中OP含量为0.8 ~ 1.7 μg/L， NP含量为18.6 ~ 44.2 μg/L。出水不含BP， OP浓度为0.0 ~ 0.1 μg/L， NP浓度为0.7 ~ 1.4 μg/L，进水与侧流之和，BP去除率为100%，OP去除率为75%，NP去除率为85%。另一方面，湿润天气下进水NP浓度是干燥天气下的3.1倍，出水NP浓度是干燥天气下的1.6倍。废活性污泥（WAS）中OP的DS含量为0.07 ~ 0.26 μg/g， NP的DS含量为0.86 ~ 3.57 μg/g； WAS与初级污泥（PS）混合污泥中OP的DS含量为0.02 ~ 0.06 μg/g， NP的DS含量为0.39 ~ 1.86 μg/g。在OP和NP浓度上，WAS比MS高2-3倍。在多摩河，富中-八谷大桥枯水期检测到NP在0.0 ~ 0.2 μg/L范围内。而在前一天的雨天，NP的浓度最大时是干燥天气时的3倍。结果表明，在联合STP下，降水对进水和出水的NP水平都有较高的影响，塔玛河的NP水平也受降水的影响。

The purpose of this study is to investigate the behavior of alkylphenol (AF) suspected of endocrine disrupting effects at a combined sewage treatment plant (STP) and at Tama river receiving effluents from several STPs in both dry and wet weather.In the influent of the STP, 4-t-butylphenol (BP) was detected in the range of 0.1-0.2 μg/L, 4-t-octylphenol (OP) of 0.2-0.4 μg/L and nonylphenol (NP) of 2.8-7.5 μg/L in dry weather. Most of OP and NP were adsorbed on the suspended solids (SS). Side stream from the sludge treatment process contained 0.8-1.7 μg/L of OP and 18.6-44.2 μg/L of NP. The effluent contained no BP, 0.0-0.1 μg/L of OP and 0.7-1.4 μg/L of NP resulting in removal rates of 100% in BP, 75% in OP and 85 % in NP toward the sum of the influent and the side stream. On the other hand, the concentration of NP in wet weather was 3.1 times higher in the influent and 1.6 times higher in the effluent than those in dry weather.Waste activated sludge (WAS) contained 0.07-0.26 μg/g DS of OP and 0.86-3.57 μg/g DS of NP and the mixed sludge (MS) of WAS and primary sludge (PS) did 0.02-0.06 μg/g DS of OP and 0.39-1.86 μg/g DS of NP. The WAS was 2-3 times higher than the MS in concentration of OP and NP.In Tama river, NP was detected in the range of 0.0-0.2 μg/L at Fuchu-Yotsuya bridge in dry weather. When it was rainy on the previous day, however, the concentration of NP was three times higher at maximum than that in dry weather.It was revealed that the level of NP at the combined STP seemed to be higher in both influent and effluent by precipitation, and that the level of NP at Tama river was also affected by precipitation.