Institute of Mining and Special Civil Engineering, Technical University Mining Academy, Gustav-Zeuner Street 1A, 09599, Freiberg, Germany.
U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Measurement and Modeling, Atlantic Coastal Environmental Sciences Division, 27 Tarzwell Drive, Narragansett, RI, 02882, USA.
Environ Sci Pollut Res Int. 2024 Sep;31(42):54546-54558. doi: 10.1007/s11356-024-34731-7. Epub 2024 Aug 29.
Equilibrium passive sampling continues to find increasing use for performing in situ assessments and monitoring of hydrophobic organic compounds (HOCs). Although this method has been successfully used in several field studies including open surface waters and sediments, comparatively, their use in groundwater has been very limited. In this study, low-density polyethylene (LDPE) passive samplers were deployed for 80 days in three groundwater wells contaminated with polycyclic aromatic hydrocarbons (PAHs). Prior to deployment, LDPE was loaded with performance reference compounds (PRCs) consisting of deuterated PAHs and their release used to ascertain system equilibrium. Within the 80-day deployment period, LDPE-groundwater equilibrium was confirmed for PAHs with molecular weights (MWs) in the range of 178 to 228 (i.e. anthracene, chrysene). Measured freely dissolved concentrations (C) were between one to three orders of magnitude lower than the total filtered concentrations (C) in the studied wells. The sum of PAHs (ΣPAHs) measured based on C and C were 2.05, 0.07 and 29.2 μg L and 197, 59.7 and 1010 μg L, at wells 1, 2 and 3, respectively. A separate dataset, comprising long-term (2010 to 2022) concentrations of PAHs in total (i.e., unfiltered) groundwater, is also presented to provide insight into PAH contamination levels at the assessed groundwater wells based on conventional measurement. Estimated in situ LDPE daily clearance volumes (2.34 to 27.56 Ld) for the target analytes were far less than the daily turnover of ground water (144 to 348 Ld) encountered in the wells eliminating the possibility of depletive sampling of the groundwater by the passive samplers. These results represent the first published study on the practical application of equilibrium passive sampling using LDPE for monitoring and quantitatively assessing PAHs in groundwater. Also, this work demonstrates that LDPEs are a useful tool for measuring the C of PAHs in groundwater, a critical contaminant in many ecological and human health risk assessments.
平衡式被动采样继续被广泛应用于进行原位评估和监测疏水性有机化合物（HOCs）。尽管该方法已在包括开阔地表水和沉积物在内的多项野外研究中得到成功应用，但在地下水方面的应用却非常有限。在本研究中，低密度聚乙烯（LDPE）被动采样器在受多环芳烃（PAHs）污染的三口地下水中部署了 80 天。在部署之前，LDPE 中装入了由氘代 PAHs 组成的性能参考化合物（PRCs），并释放它们以确定系统平衡。在 80 天的部署期间，LDPE-地下水对分子量（MW）在 178 至 228 范围内的 PAHs 达到了平衡（即蒽、屈）。测量得到的自由溶解浓度（C）比研究井中总过滤浓度（C）低 1 至 3 个数量级。基于 C 和 C 测量的 PAHs 总和（ΣPAHs）分别为 2.05、0.07 和 29.2μg/L 和 197、59.7 和 1010μg/L，在井 1、2 和 3 中分别为 2.05、0.07 和 29.2μg/L 和 197、59.7 和 1010μg/L。还提供了另一个数据集，包括 2010 年至 2022 年期间总（即未过滤）地下水中 PAHs 的长期浓度，根据常规测量，为评估地下水井中的 PAH 污染水平提供了参考。对于目标分析物，估计的原位 LDPE 每日清除量（2.34 至 27.56 Ld）远小于井中遇到的地下水日周转率（144 至 348 Ld），从而排除了被动采样器耗尽地下水中目标分析物的可能性。这些结果代表了首次使用 LDPE 进行平衡式被动采样以监测和定量评估地下水中 PAHs 的实际应用的研究。此外，这项工作表明 LDPE 是测量地下水 PAHs C 的有用工具，PAHs 是许多生态和人类健康风险评估中的关键污染物。
