Centre for Aquatic Pollution, Identification, and Management, Bio21 Institute, University of Melbourne, Parkville, VIC, Australia.
Arch Environ Contam Toxicol. 2011 Nov;61(4):539-46. doi: 10.1007/s00244-011-9665-z. Epub 2011 Apr 3.
This project involved the collection of final effluent samples from 39 wastewater-treatment plants (WWTPs) in Victoria, Australia, in late summer (late February to early March 2007). The 39 WWTPs included 15 lagoon-based plants and 24 with activated sludge-based processes. Samples were collected and subjected to measurement of retinoic acid receptor (RAR) and aryl hydrocarbon receptor (AhR) activity of the dissolved phase using yeast-based recombinant receptor-reporter gene bioassays. More than 90% of the effluents examined in this study elicited RAR activity (<0.5-198 ng/l a-t-RA equivalents [EQ]). All of the effluents had AhR activity (16-279 ng/l βNF EQ). Notwithstanding the paucity of comparative data, on the whole, the levels of RAR and AhR activity observed in this pilot survey of Victorian WWTP effluents were greater than those recently reported internationally. One assumption commonly made is that WWTP discharges will be diluted significantly in the receiving environment, further decreasing the potential risk of the discharges. Making this assumption may not be appropriate for some of Victoria's more ephemeral waterways or where effluent is discharged to an enclosed water body, such as a lake or terminal wetland. However, even where WWTP discharges represent all of the environmental flow in the warmer months, the observed RAR and AhR activity (as all-trans-retinoic acid (RA) and 2,3,7,8-tetrachloro-dibenzo-p-dioxin [TCDD] EQ, respectively) was still significantly lower than the concentrations of RA, and 2,3,7,8-TCCD known to cause developmental malformations in fish larvae after short-term exposure to these chemicals. Of perhaps greater concern, WWTP effluent can contain significant suspended solids (essentially biosolids), which may be a considerable sink for some hormonally active, hydrophobic compounds, and which may in turn increase the long-term exposure risk for aquatic fauna. Further studies of the nuclear and AhR activity of WWTP effluent suspended soilds are required to address this hypothesis.
本项目涉及从澳大利亚维多利亚州的 39 家废水处理厂（WWTP）收集最终废水样品，时间为夏末（2007 年 2 月下旬至 3 月初）。这 39 家 WWTP 包括 15 家基于塘的工厂和 24 家基于活性污泥的工厂。收集样品并使用基于酵母的重组受体报告基因生物测定法测量溶解相中视黄酸受体（RAR）和芳烃受体（AhR）的活性。本研究中检查的超过 90％的废水均表现出 RAR 活性（<0.5-198ng/l a-t-RA 当量[EQ]）。所有废水均具有 AhR 活性（16-279ng/l βNF EQ）。尽管缺乏比较数据，但总体而言，在维多利亚 WWTP 废水的初步调查中观察到的 RAR 和 AhR 活性水平高于国际上最近报道的水平。通常的假设是 WWTP 排放物在接受环境中会被大大稀释，从而进一步降低排放物的潜在风险。对于维多利亚州一些更短暂的水道或废水排放到封闭水体（如湖泊或终端湿地）的情况，这种假设可能并不合适。但是，即使 WWTP 排放物代表了温暖月份的所有环境流量，观察到的 RAR 和 AhR 活性（分别为全反式视黄酸（RA）和 2,3,7,8-四氯二苯并对二恶英[TCDD] EQ）仍明显低于已知会导致鱼类幼虫短期暴露于这些化学物质后发生发育畸形的 RA 和 2,3,7,8-TCCD 的浓度。也许更令人担忧的是，WWTP 废水可能含有大量的悬浮固体（本质上是生物固体），这可能是一些具有激素活性的疏水性化合物的重要汇，这反过来又可能增加水生动物的长期暴露风险。需要进一步研究 WWTP 废水悬浮固体的核受体和 AhR 活性，以验证这一假设。
