Soil and Water Quality Laboratory, Gulf Coast Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 14625 CR 672, Wimauma, FL 33598, USA.
Soil and Water Quality Laboratory, Gulf Coast Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 14625 CR 672, Wimauma, FL 33598, USA.
Water Res. 2017 Oct 15;123:258-267. doi: 10.1016/j.watres.2017.06.054. Epub 2017 Jun 21.
Septic systems may contribute micropollutants to shallow groundwater and surface water. We constructed two in situ conventional drainfields (drip dispersal and gravel trench) and an advanced drainfield of septic systems to investigate the fate and transport of micropollutants to shallow groundwater. Unsaturated soil-water and groundwater samples were collected, over 32 sampling events (January 2013 to June 2014), from the drainfields (0.31-1.07 m deep) and piezometers (3.1-3.4 m deep). In addition to soil-water and groundwater, effluent samples collected from the septic tank were also analyzed for 20 selected micropollutants, including wastewater markers, hormones, pharmaceuticals and personal care products (PPCPs), a plasticizer, and their transformation products. The removal efficiencies of micropollutants from septic tank effluent to groundwater were similar among three septic systems and were 51-89% for sucralose and 53->99% for other micropollutants. Even with high removal rates within the drainfields, six PPCPs and sucralose with concentrations ranging from <0.3 to 154 ng/L and 121 to 32,000 ng/L reached shallow groundwater, respectively. The human health risk assessment showed that the risk to human health due to consumption of groundwater is negligible for the micropollutants monitored in the study. A better understanding of ecotoxicological effects of micropollutant mixtures from septic systems to ecosystem and human health is warranted for the long-term sustainability of septic systems.
污水系统可能会向浅层地下水和地表水排放微量污染物。我们构建了两个原位常规排水系统（滴灌分散和砾石沟渠）和一个先进的污水系统排水系统，以研究微量污染物向浅层地下水的迁移和归宿。在 32 次采样事件（2013 年 1 月至 2014 年 6 月）中，从排水系统（0.31-1.07 米深）和测压管（3.1-3.4 米深）中采集了非饱和土壤-水和地下水样品。除了土壤-水和地下水，还从化粪池中采集了污水样本，用于分析 20 种选定的微量污染物，包括废水标志物、激素、药物和个人护理产品 (PPCPs)、增塑剂及其转化产物。化粪池污水中微量污染物向地下水的去除效率在三种污水系统中相似，对于三氯蔗糖为 51-89%，对于其他微量污染物为 53->99%。即使在排水系统内有很高的去除率，六种 PPCPs 和三氯蔗糖的浓度范围分别为<0.3 至 154 ng/L 和 121 至 32,000 ng/L，也达到了浅层地下水。人类健康风险评估表明，对于本研究中监测到的微量污染物，饮用地下水对人类健康造成的风险可以忽略不计。为了确保污水系统的长期可持续性，有必要更好地了解污水系统中微量污染物混合物对生态系统和人类健康的生态毒理学影响。
