Water and Air Quality Laboratory, Department of Environment, University of the Aegean, University Hill, Mytilene, Greece.
Bioresour Technol. 2010 Apr;101(7):2090-5. doi: 10.1016/j.biortech.2009.10.086. Epub 2009 Nov 24.
The fate of three endocrine-disrupting compounds (EDCs), namely 4-n-nonylphenol (4-n-NP), triclosan (TCS) and bisphenol A (BPA), was studied in activated sludge process. The effect of sludge retention time (SRT) on their sorption and biodegradation was also investigated. Three continuous-flow activated sludge systems were used, operating at SRT of 3, 10 and 20 days, respectively. Batch experiments with biomass originated from the aforementioned systems showed that 4-n-NP and TCS are significantly sorbed on the suspended solids, while BPA to a lesser extent. The sorption affinity of target compounds did not seem to be affected by SRT, with the exception of 4-n-NP for which higher values of sorption coefficients were calculated at SRT of 3 days. The operation of continuous-flow systems in the presence of 10-40 microgL(-1) of EDCs indicated that more than 90%, 94% and 97% of BPA, TCS and 4-n-NP, respectively, can be removed during the activated sludge process in systems operating at SRT of 3-20 days. Determination of EDCs in the dissolved and particulate phase and calculation of their mass flux revealed that biodegradation was the principal removal mechanism of EDCs. For SRT values used in this study, this parameter does not seem to affect significantly percentage biodegradation of BPA. On the other hand, biodegradation of 4-n-NP and TCS was enhanced at SRT of 20 days. Calculation of biotransformation rates showed that the highest values for all EDCs were calculated at SRT of 3 days.
三种内分泌干扰化合物（EDCs），即 4-壬基酚（4-n-NP）、三氯生（TCS）和双酚 A（BPA），在活性污泥工艺中的命运进行了研究。还研究了污泥停留时间（SRT）对它们的吸附和生物降解的影响。使用了三个连续流活性污泥系统，分别在 SRT 为 3、10 和 20 天的条件下运行。来自上述系统的生物量的批量实验表明，4-n-NP 和 TCS 显著吸附在悬浮固体上，而 BPA 的吸附程度较小。目标化合物的吸附亲和力似乎不受 SRT 的影响，除了 4-n-NP，在 SRT 为 3 天时，计算出的吸附系数值较高。在存在 10-40 μg/L 的 EDCs 的连续流系统中运行表明，在 SRT 为 3-20 天的系统中，BPA、TCS 和 4-n-NP 的去除率分别超过 90%、94%和 97%。在溶解相和颗粒相测定 EDCs 并计算其质量通量表明，生物降解是 EDCs 的主要去除机制。对于本研究中使用的 SRT 值，该参数似乎不会显著影响 BPA 的生物降解百分比。另一方面，在 SRT 为 20 天时，4-n-NP 和 TCS 的生物降解得到了增强。生物转化速率的计算表明，所有 EDCs 的最高值均在 SRT 为 3 天时计算得出。
