Department of Microbiology, Faculty of Biology, University of Barcelona, Spain.
Water Sci Technol. 2012;66(12):2517-23. doi: 10.2166/wst.2012.233.
This study involved collaboration between three centres with expertise in viruses, bacteria and protozoa. The focus of the research was the study of the dissemination and removal of pathogens and faecal indicators in two sewage treatment plants (STP1 and STP2) using tertiary treatments. Samples were collected over a period of five months through the sewage treatment processes. Analysis of the samples revealed that the plants were not efficient at removing the faecal indicators and pathogens tested during the study. From entry point (raw sewage) to effluent level (tertiary treatment effluent water), the experimental results showed that the reduction ratios of human adenoviruses were 1.2 log₁₀ in STP1 and 1.9 log₁₀ in STP2. Whereas for Giardia spp. and Cryptosporidium spp. the reduction ratios were 2.3 log₁₀ for both pathogens in STP1, and 3.0 and 1.7 log₁₀ in STP2, respectively. Furthermore, the presence of faecal indicators and pathogens at different sampling points was evaluated revealing that the tested pathogens were present in reclaimed water. Human adenovirus and Arcobacter spp. showed positive results in infectivity assays for most of the tertiary effluent water samples that comply with current legislation in Spain. The pathogens detected must be evaluated using a risk assessment model, which will be essential for the development of improved guidelines for the re-use of reclaimed water.
本研究涉及三个在病毒、细菌和原生动物方面具有专业知识的中心之间的合作。研究的重点是使用三级处理研究两种污水处理厂（STP1 和 STP2）中病原体和粪便指标的传播和去除。在五个月的时间里，通过污水处理过程收集了样本。对样本的分析表明，这些工厂在去除研究中测试的粪便指标和病原体方面效率不高。从入口点（原污水）到出水水平（三级处理出水），实验结果表明，人类腺病毒在 STP1 中的减少率为 1.2log₁₀，在 STP2 中的减少率为 1.9log₁₀。而对于贾第虫属和隐孢子虫属，两种病原体在 STP1 中的减少率均为 2.3log₁₀，而在 STP2 中的减少率分别为 3.0 和 1.7log₁₀。此外，还评估了不同采样点处粪便指标和病原体的存在情况，结果表明测试病原体存在于再生水中。在符合西班牙现行法规的大多数三级处理出水样本中，人腺病毒和弯曲菌属的感染性检测呈阳性结果。必须使用风险评估模型对检测到的病原体进行评估，这对于制定改进的再生水再利用指南至关重要。
