Evaluation of the microbiological quality of reclaimed water produced from a lagooning system
Evaluation of the microbiological quality of reclaimed water produced from a lagooning system
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DOI：
10.1007/s11356-016-6812-0
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发表时间：
2016-08-01
影响因子：
5.8
通讯作者：
Bofill-Mas, S.
中科院分区：
文献类型：
--
作者：
Fernandez-Cassi, X.;Silvera, C.;Bofill-Mas, S.
使用泻湖作为处理污水处理厂二级出水的补充自然方法，已被用作生产再生水的负担得起且简单的方法。然而，将再生水用于某些目的，例如用于食品灌溉，如果废水含有微生物病原体，则会带来一些风险。用于评估水中粪便污染的经典细菌指示剂并不总是正确地指示细菌或病毒病原体的存在。在目前的研究中，粪便指示细菌（FIB）、异养细菌计数（HBC）、病原体和条件致病菌（如军团菌属）的存在，气单胞菌属，弓形杆菌属，分析了1年来进出水中自由生活阿米巴（弗拉）、几种病毒指示物（人腺病毒和多瘤病毒JC）和病毒病原体（诺如病毒和戊型肝炎病毒），以评估泻湖系统的去除效率。我们观察到，在入口和出口样品之间，大肠杆菌（EC）和肠球菌（IE）分别减少了2.58（1.17-4.59）和1.65（0.15-3.14）log。对于人腺病毒（HAdV）、JC多瘤病毒（JCPyV）和人诺如病毒（NoV GI和GII），病毒的基因组拷贝分别对数减少1.18（0.24 - 2.93）、0.64（0.12-1.97）、0.45（0.04-2.54）和0.72（0.22-2.50）。系统内未观察到机会致病菌的再生长。在所有样品中检测到的弗拉没有显示出明显的趋势。粪便病原体的减少是不规则的，12个样品中有6个和12个样品中有4个超过了西班牙再生水法规（RD 1620/2007）中规定的EC和IE值。这一数据表明，有必要进行更多的研究，以评估泻湖系统的去除机制，以优化病原体减少。此外，应监测用于灌溉生食蔬菜的水，以确保满足生产安全再生水的微生物要求。
The use of lagooning as a complementary natural method of treating secondary effluents of wastewater treatment plants has been employed as an affordable and easy means of producing reclaimed water. However, using reclaimed water for some purposes, for example, for food irrigation, presents some risks if the effluents contain microbial pathogens. Classical bacterial indicators that are used to assess faecal contamination in water do not always properly indicate the presence of bacterial or viral pathogens. In the current study, the presence of faecal indicator bacteria (FIB), heterotrophic bacterial counts (HBC), pathogens and opportunistic pathogens, such as Legionella spp., Aeromonas spp., Arcobacter spp., free-living amoeba (FLA), several viral indicators (human adenovirus and polyomavirus JC) and viral pathogens (noroviruses and hepatitis E virus) were analysed for 1 year in inlet and outlet water to assess the removal efficiency of a lagooning system. We observed 2.58 (1.17-4.59) and 1.65 (0.15-3.14) log reductions in Escherichia coli (EC) and intestinal enterococci (IE), respectively, between the inlet and outlet samples. Genomic copies of the viruses were log reduced by 1.18 (0.24-2.93), 0.64 (0.12-1.97), 0.45 (0.04-2.54) and 0.72 (0.22-2.50) for human adenovirus (HAdV), JC polyomavirus (JCPyV) and human noroviruses (NoV GI and GII), respectively. No regrowth of opportunistic pathogens was observed within the system. FLA, detected in all samples, did not show a clear trend. The reduction of faecal pathogens was irregular with 6 out of 12 samples and 4 out of 12 samples exceeding the EC and IE values, specified in the Spanish legislation for reclaimed water (RD 1620/2007). This data evidences that there is a need for more studies to evaluate the removal mechanisms of lagooning systems in order to optimize pathogen reduction. Moreover, surveillance of water used to irrigate raw edible vegetables should be conducted to ensure the fulfilment of the microbial requirements for the production of safe reclaimed water.