Centre for Aquatic Pollution Identification and Management (CAPIM), Bio 21 Institute, The University of Melbourne, Parkville, Victoria 3052, Australia.
Water Res. 2013 Mar 15;47(4):1604-15. doi: 10.1016/j.watres.2012.12.020. Epub 2012 Dec 23.
Estuaries are often the final repositories for aquatic pollutants but how estuarine hydrology influences the availability of marine- and freshwater-derived pollutants is not well understood, particularly for micro-pollutants such as endocrine disrupting chemicals. To address this knowledge gap, this study measured natural and synthetic estrogen concentrations within the Little River, a tidal estuary in close vicinity to the major discharge point of Melbourne's largest waste water treatment plant (WWTP), the Western Treatment Plant. Quantitative enzyme-linked immunosorbent assays (ELISA) were used to determine concentrations of natural estrogens (ES: ∑E1 (estrone), E2 (17β-estradiol), E3 (estriol)) and the synthetic estrogen, 17α-ethinylestradiol (EE2). The highest concentrations were measured in samples taken from the WWTP effluent discharge channel (29.0 ng/L and 0.35 ng/L, respectively). Within the estuary, concentrations of ES (2.25-23.16 ng/L) varied somewhat between locations and sampling periods (p < 0.05), however patterns were not consistent. Significant spatial variation was observed on only one sampling occasion, and likewise temporal variation was only observed once. In the upstream freshwaters, ES (2.95-7.26 ng/L) concentrations were lower than in the estuary, although their presence suggests an additional source of ES to the environment, most likely of agricultural origin. The EE2 concentrations measured in both the estuarine and freshwater areas were all low (mostly below 0.20 ng/L), which created difficulties in interpretation due to problems associated with trying to measure such low concentrations with confidence. However, some patterns did emerge, with EE2 concentrations exhibiting significant temporal and tidal variation (p < 0.05), with concentrations greatest during low and flooding (incoming) tides. Physico-chemical properties explained 30% of the variation in ES concentrations, whereby concentrations increased with decreasing pH and DO and increasing salinity. Given the higher concentrations observed during flooding tides and the association of higher estrogen concentrations with increased salinity and low DO, we suggest that estrogens might accumulate in estuarine bottom waters and upon disturbance from the incoming tidal flows, may be a contributing source of estrogens into the estuary. This study contributes the first comprehensive investigation of estrogen dynamics in an Australian estuary, and provides the foundation for further research aimed at identifying which compounds are present in estuarine waterways, where they are coming from and how their concentrations vary through space and time.
河口通常是水生污染物的最终储存库，但河口水文学如何影响海洋和淡水来源污染物的可利用性尚不清楚，特别是对于内分泌干扰化学物质等微量污染物。为了填补这一知识空白，本研究测量了潮汐河口小河中的天然和合成雌激素浓度，该河口紧邻墨尔本最大的污水处理厂（西部处理厂）的主要排放点。定量酶联免疫吸附测定（ELISA）用于测定天然雌激素（ES：∑E1（雌酮）、E2（17β-雌二醇）、E3（雌三醇））和合成雌激素 17α-乙炔基雌二醇（EE2）的浓度。在污水处理厂排放通道中采集的样本中，浓度最高（分别为 29.0ng/L 和 0.35ng/L）。在河口内，ES（2.25-23.16ng/L）的浓度在不同地点和采样时间之间有所不同（p<0.05），但模式并不一致。仅在一次采样时观察到显著的空间变化，同样仅在一次采样时观察到时间变化。在上游淡水中，ES（2.95-7.26ng/L）的浓度低于河口，尽管其存在表明环境中还有其他 ES 来源，很可能来自农业。在河口和淡水区域测量的 EE2 浓度均较低（大多低于 0.20ng/L），由于试图以信心测量如此低的浓度所带来的问题，这使得解释变得困难。然而，确实出现了一些模式，EE2 浓度表现出显著的时间和潮汐变化（p<0.05），在低潮和涨潮（入流）时浓度最高。理化性质解释了 ES 浓度变化的 30%，其中浓度随 pH 值和 DO 降低以及盐度增加而增加。鉴于在涨潮时观察到的浓度较高，以及较高的雌激素浓度与盐度增加和 DO 降低有关，我们认为雌激素可能在河口底部水中积累，并且在来自传入的潮汐流的干扰下，可能成为雌激素进入河口的一个来源。本研究首次全面调查了澳大利亚河口的雌激素动态，并为进一步研究奠定了基础，旨在确定哪些化合物存在于河口水道中，它们来自何处以及它们的浓度如何通过空间和时间变化。
