活性氧溶液灭活饮用水中隐孢子虫的机理与机制研究

Waterborne cryptosporidiosis outbreaks frequently all over the world in recent years, threatening the safety of drinking water and the health of people. In China, many sources of drinking water have been contaminated by the cryptosporidium, owning to the accelerated development of Urbanization and serious environmental pollution. And the conventional water treatment processes, including coagulation, sedimentation, filtration and chlorine disinfection, could not completely remove the cryptosporidium in water. Thus, there is a great potential for the outbreak of waterborne cryptosporidiosis in our country. At present, few researches are focused on the inactivation technologies of cryptosporidium. And the inactivation mechanism of cryptosporidium in water is not clearly yet. Therefore, to ensure the safety supply of drinking water, it is very important and urgent to investigate the mechanism of cryptosporidium inactivation and develop efficient inactivation technologies. In this project, the main concentration is focused on solving the key scientific questions about the safety protection of drinking water. The inactivation mechanism of cryptosporidium treated by reactive oxygen solution will be intensively studied. And the major active factor in the reactive oxygen solution, as well as the optimum forming conditions will be investigated. Based on these studies, theoretical basis and technical parameters could be obtained and provided for the development of efficient technologies for cryptosporidium inactivation, which has great significance on protecting the safety of drinking water, reducing the outbreak of public health events, and safeguarding people's lives and health.

近年来，以饮用水为媒介的隐孢子虫疾病频繁暴发，对饮用水安全构成严重威胁。我国城镇化加速发展，环境污染加剧，饮用水源受隐孢子虫污染较为严重，而常规饮用水处理工艺（混凝-沉淀-过滤-氯化消毒）无法彻底清除水中的隐孢子虫，存在暴发水介隐孢子虫疾病的严重隐患。因此，研究饮用水中隐孢子虫的灭活机制，开发有效灭活隐孢子虫的水处理工艺和技术，是目前保障我国饮用水水质安全的重要、迫切任务。本项目针对保障饮用水安全急需解决的关键科学问题，重点研究活性氧溶液中活性物质对隐孢子虫的灭活效率及影响因素，探讨活性氧溶液致死隐孢子虫的生物机理和作用机制，揭示活性氧溶液中关键活性物质的形成条件和反应途径，阐明活性氧致死隐孢子虫的关键损伤模式，为建立高效、安全灭活隐孢子虫的技术工艺提供理论依据和技术参数支持，对保证饮用水水质安全、减少或应对突发性公共卫生事件、保障人民生命健康等具有重要意义。

我国城镇化加速发展，环境污染加剧，饮用水源受隐孢子虫污染日益严重，而常规饮用水处理工艺（混凝—沉淀—过滤—氯化消毒）无法彻底清除水中的隐孢子虫，存在暴发水介隐孢子虫疾病的重大隐患,对饮用水安全构成严重威胁。本项目针对保障饮用水安全急需解决的关键科学问题，围绕开发隐孢子虫有效灭活水处理工艺和技术的目标，依据“活性氧自由基快速致死水中隐孢子虫”技术路线，重点开展了大气压强电场放电高效生成活性氧自由基、活性氧溶液快速灭活水中微生物技术模式及致死机理机制、饮用水活性氧自由基快速高效消毒技术安全评估等研究工作。. 项目研究确立了大气压强电场放电技术产生的活性氧溶液含有的主要活性物质，建立了羟基自由基、过氧化氢以及超氧阴离子等不同活性物质浓度的检测方法，并优化了活性氧溶液中关键活性物质的形成条件和反应途径，实验获得的最高活性氧自由基和羟基自由基浓度分别为12mg/L和70μmol/L；明确了活性氧自由基灭活水中微生物的剂效、时效关系，以及水体浊度、有机物含量等水质参数因素对活性氧自由基灭活微生物效果的影响，实验获得活性氧自由基致死水中大肠杆菌的阈值浓度为0.5-0.7mg/L，致死隐孢子虫的阈值浓度为2mg/L左右，灭活时间为3-30s，同时阐明了活性氧自由基致死病原微生物的重要机制是羟基自由基等的强氧化作用造成细胞膜破损、细胞内容物（蛋白质等）降解；验证了大气压强电场放电技术产生的活性氧溶液致死生活饮用水病原微生物工艺的有效性和适用性，经2mg/L活性氧自由基处理后，大连某水库水源水中的隐孢子虫含量< 1个/10L，达到国家《生活饮用水卫生标准》（GB5749-2006），处理后水体水质得到了明显改善。研究结果可为建立高效、安全灭活隐孢子虫的技术工艺提供理论依据和技术参数支持，对保证饮用水水质安全、减少或应对突发性公共卫生事件、保障人民生命健康等具有重要意义。