Fries Elke, Gocht Tilman, Klasmeier Jörg
Institute of Environmental Systems Research, University of Osnabrueck, Barbarastrasse 12, D-49090, Osnabrueck, Germany.
J Environ Monit. 2011 Oct;13(10):2838-43. doi: 10.1039/c1em10474h. Epub 2011 Aug 23.
This study quantifies the regional distribution of the micropollutant benzothiazole (BT) in river water by sampling 15 river sites in the Schwarzbach watershed (about 400 km(2)) from November 2008 to February 2010. Additionally, wastewater samples from three municipal wastewater treatment plants (WWTPs) in Germany were analyzed. BT was detected in all wastewater influent and effluent samples as well as in all river water samples collected downstream of wastewater discharge. This corroborates the ubiquitous occurrence of BT in the aqueous environment. Concentrations were between 58 and 856 ng L(-1) in the river water. The observed mean concentration at the outlet of the investigated catchment was 109 ng L(-1). With only a few exceptions, temporal and spatial variations of BT concentrations in river water were low. Rather similar BT concentrations over a wide range of river discharge indicate that dilution along the mainstream is negligible and, thus, supports the hypothesis that paved surface runoff during rain events is an important BT source not only for wastewater influent but also for river water. This was supported by detecting the highest BT concentrations at sampling locations close to the dense highway network around the city of Frankfurt. Since BT was also detected in river water collected from locations that were clearly unaffected by wastewater effluent discharge, surface runoff must be considered as a diffuse source of BT in river water.
本研究通过在2008年11月至2010年2月期间对施瓦茨巴赫流域（约400平方公里）的15个河流采样点进行采样，对河水中微量污染物苯并噻唑（BT）的区域分布进行了量化。此外，还分析了德国三个城市污水处理厂的废水样本。在所有废水进水和出水样本以及废水排放下游采集的所有河水样本中均检测到了BT。这证实了BT在水环境中普遍存在。河水中的浓度在58至856纳克/升之间。在所研究流域出口处观测到的平均浓度为109纳克/升。除少数例外情况外，河水中BT浓度的时空变化较小。在较宽的河流流量范围内，BT浓度相当相似，这表明沿主流的稀释作用可忽略不计，因此支持了这样一种假设，即降雨期间的路面径流不仅是废水进水而且也是河水的重要BT来源。这一点在法兰克福市周围密集公路网附近的采样点检测到最高BT浓度得到了支持。由于在明显未受废水排放影响的地点采集的河水中也检测到了BT，因此必须将地表径流视为河水中BT的一个分散来源。
