Institute of Environmental Science and Research, PO Box 29181, Christchurch, 8540, New Zealand; Waterways Centre for Freshwater Management, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand.
Institute of Environmental Science and Research, PO Box 29181, Christchurch, 8540, New Zealand.
Water Res. 2020 Feb 1;169:115272. doi: 10.1016/j.watres.2019.115272. Epub 2019 Nov 6.
Contamination of potable groundwater by pathogenic viruses from on-site wastewater treatment systems (OWTS) poses a serious health risk. This study investigated the attenuation and transport of rotavirus, bacteriophage MS2 and DNA-labelled-glycoprotein-coated silica nanoparticles (DGSnp) in 2 intact cores of silt loam over gravels dosed with wastewater from an OWTS at 3.53 L/day. To simulate a worst-case scenario, experiments were conducted under saturated conditions. The results from 6 experiments demonstrated that the rotavirus and DGSnp reductions were very similar and markedly greater than the MS2 reduction. This was reflected in the peak concentrations, relative mass recoveries, and temporal and spatial reduction rates. For a given log reduction, the estimated soil depth required for MS2 was over twice that required for rotavirus and DGSnp. This is the first study in which DGSnp was used as a rotavirus surrogate in soil under wastewater applications. Consistent with previous studies, DGSnp showed promise at mimicking rotavirus attenuation and transport in porous media. The results suggest DGSnp could be used to assess the attenuation capacity of subsurface media to rotavirus. However, DGSnp is not conservative and will underestimate the setback distances required for rotavirus reductions by 3%. On the other hand, separation distances determined using the rotavirus parameters and criteria but based on MS2 attenuation, can be too conservative in some subsurface media. To determine safe and realistic separation distances, it would be beneficial and complementary to apply both conservative virus surrogate using MS2 bacteriophage and representative but non-conservative new virus surrogates using biomolecule-modified silica nanoparticles.
受现场污水处理系统 (OWTS) 的致病病毒污染的饮用水地下水会对健康造成严重威胁。本研究调查了在受 OWTS 污水以 3.53 L/天剂量处理的砂壤土完整芯中的轮状病毒、噬菌体 MS2 和 DNA 标记糖蛋白包覆的硅胶纳米颗粒 (DGSnp) 的衰减和迁移。为了模拟最坏情况，在饱和条件下进行了实验。6 项实验的结果表明，轮状病毒和 DGSnp 的减少非常相似，明显大于 MS2 的减少。这反映在峰值浓度、相对质量回收率以及时间和空间减少率上。对于给定的对数减少，MS2 所需的估计土壤深度是轮状病毒和 DGSnp 的两倍多。这是首次在废水应用中使用 DGSnp 作为土壤中轮状病毒替代物的研究。与先前的研究一致，DGSnp 在模拟多孔介质中轮状病毒衰减和迁移方面表现出很大的潜力。研究结果表明，DGSnp 可用于评估地下介质对轮状病毒的衰减能力。然而，DGSnp 不保守，会低估轮状病毒减少所需的 3%的后退距离。另一方面，基于 MS2 衰减确定的分离距离可能在某些地下介质中过于保守。为了确定安全和现实的分离距离，应用 MS2 噬菌体等保守病毒替代物和使用生物分子修饰的硅胶纳米颗粒等代表性但不保守的新病毒替代物将是有益和互补的。
