水产养殖水体富营养化过程中抗生素、抗性基因和抗性细菌的暴露、转移机制研究

Large quantities of antibiotics are administered to humans and animals to treat diseases and infection every year.Antibiotics are also commonly used at sub-therapeutic levels to livestock to prevent diseases and promote growth. As results of incomplete metabolism and absorption,up to 85% of administered antibiotics with the parent compound and their metabolites may be excreted into the environment via animal manure and human waste, and then be discharged to the soil and water system through different exposure routes.Despite the detection of antibiotics,little is known about their distribution,transport and persistence in natural and engineered systems. Presence of antibiotics in environment could perturb ecosystem including bacteria,water and soil microorganism and plants, increase the proliferation of antibiotics-resistant pathogens, and could pose threats to human health.Recent studies had indicated large scale use of antibiotics induces the increasing emergence of antibiotic resistance bacteria and antibiotic resistance genes (ARGs)，and，as a kind of new environmental contaminants，the ARGs are attracted much attention by the public.Bacteria have been shown to readily share genetic information by horizontal gene transfer mechanism driven by mobile genetic elements, permitting the transfer of resistance genes from fecal microorganisms to indigenous environmental bacteria.This study aims to investigate exposure concentration and kind of tetracyclines(TCs) in aquaculture water and determine the tranport mechanism of TCs ARGs and resistance bacteria in aquaculture ecosystem by laboratory and field test. Risk assessment of ARGs will be done according to the study results.

抗生素在保障人类健康和促进水产业发展方面发挥了重要作用。但抗生素的过度使用引起了人们的广泛关注，主要集中于日益出现的抗生素抗（耐）药菌和抗性基因。世界卫生组织已将抗生素抗性基因作为21世纪威胁人类健康的最重大挑战之一。水产养殖是抗生素、抗性基因进入水环境最直接的途径。本项研究旨在国内外已有研究成果基础上，通过对水产品养殖现场水环境实地调查，结合实验室模拟试验，分析不同富营养化水环境中，氮、磷营养盐水平，温度、光照等环境因素对四环素类抗生素暴露的影响效应，探讨水环境、水生生物以及沉积物生态系统中四环素类抗生素、抗性基因和抗性细菌的种类分布、相互关系、转移特征与机制。对新型环境污染物抗性基因的研究将引起公众和政府权利机构对基因污染的重视，进而制定相应政策并加强监管力度，最终有助于评估、减轻或控制基因污染对生态环境和人体健康造成的危害，并推动公共卫生事业健康发展。

抗生素在保障人类健康和促进水产业发展方面发挥了重要作用。但抗生素的过度使用引起了人们的广泛关注。水产养殖是抗生素、抗性基因进入水环境最直接的途径。本研究通过对江苏省典型水产品养殖区域的现场调查，分析测试了不同富营养化水平下养殖水体和沉积物中主要抗生素种类、水平，探讨了抗生素、抗性细菌与抗性基因的相互关系、转移机制。结果表明，水产养殖水体和沉积物中主要抗生素浓度较低，但也存在一定生态风险，建议有关部门严格规范水产养殖的抗生素使用，保护水产生态系统的健康。