【作者】 刘学慧；

【导师】 孙增荣； 吕严； 吴丽娜； 任大林；

【作者基本信息】 天津医科大学 ， 劳动卫生与环境卫生学， 2005， 硕士

【摘要】 目的:由于水资源缺乏,我国很多地区利用城市污水进行农田灌溉和水产养殖。国内外研究证实污水中含有大量的有毒有害物质,其中有一部分是持久性有机污染物(Persistent Organic Pollutants,POPs)。由于持久性有机污染物具有难以降解、易于生物富集等特性,可以通过食物链进入到人体内,从而对人类健康产生潜在的危害。为评价养殖污水中有机污染物对人类健康造成潜在危害的可能性,本研究对采自天津市西青区某污水养鱼池的养殖用水有机提取物的遗传毒性进行了检测。本研究尚通过观察养殖污水有机提取物对雄性小鼠生殖器官脏器系数及组织形态学的影响,初步探讨其生殖内分泌干扰作用。 方法:分别于春季放鱼苗前(样品A)和秋季捕获期(样品B)采集天津市西青区某污水养鱼池污水,用XAD-2树脂提取有机物。每个样品提取水样150L,提取物经K-D浓缩、真空干燥后用二甲基亚砜(DMSO)定容至30毫升。①健康昆明种小鼠按体重随机分组,每组8只,雌雄各半。以养殖污水有机提取物原液(25L/kg)、1/2剂量(12.5L/kg)、1/4剂量(6.25L/kg)、1/8剂量(3.125L/kg)对小鼠染毒,以DMSO为阴性对照,环磷酰胺(CP 40mg/kg)为阳性对照,小鼠均按0.1ml/20g·bw腹腔注射染毒,连续3天。通过小鼠骨髓嗜多染红细胞(PCE)微核试验和小鼠外周血淋巴细胞非荧光染色彗星试验检测养殖污水中有机污染物所致的染色体损伤及DNA损伤作用。②分别取小鼠脾细胞悬液2ml,加不同浓度的受试物2μl,设三个染毒剂量组,终浓度分别相当于2.5ml、1.25ml、0.625ml水样,以DMSO为阴性对照,重铬酸钾(0.2mmol/L)为阳性对照,37℃染毒2h。通过小鼠脾细胞体外更多还原

【Abstract】 Objective: Because of the shortage of the water resource, many areas in china utilize municipal sewage for agriculture irrigation and aquaculture. Domestic and overseas studies showed that there were a large number of hazardous chemicals in the sewage, including some kinds of Persistent Organic Pollutants (POPs). Because it is hard for POPs to degrade and easy to bioaccumulate, once POPs enter human body through the food chains, potential harms can be imposed to human health. To evaluate the possibility of the potential hazardous health effects on the human beings induced by the organic pollutants in the fishpond water, the genotoxicity of the organic extracts (OEs) in the fishpond water containing the sewage were detected. To primarily study the reproduction-endocrine disrupting effects of POPs in the fishpond water, the genital organs’ coefficients of male mice exposed to the OEs were determined and the histopathological changes were observed using the optics microscope. Methods: Fishpond water containing sewage from Xiqing District in Tianjin was collected in spring (sample A) and autumn (sample B) respectively, organic pollutants in the water samples were extracted using XAD-2 resins, 150L water for each water sample was extracted. After being K-D condensed and vacuum dried, the OEs were dissolved into 30ml dimethylsulfoxide (DMSO). ①Healthy Kunming mice were randomly divided into 6 groups according to the body weight, 8 mice each group. Themice were administrated through peritoneal injection with OEs at the doses of equivalent to 2517kg, 12.5L/kg, 6.25L/kg, 3.125L/kg water sample respectively, continuously for 3 days. The negative and positive control groups were administrated with DMSO and cyclophosphamide (CP) respectively. The effects of chromosome damage and DNA damage induced by the OEs were detected using mice bone marrow micronudeus test and un-fluorescent staining comet assay of mice peripheral blood lymphocytes. ?Separated mouse spleen cells were respectively treated by OEs at doses of equivalent to 2.5ml, 1.25ml, 0.625ml water sample per 2ml soliquid of the spleen cells for 2h at 37 °C. The negative and positive control groups were treated with DMSO and potassium dichromate (0.2mmol/L) respectively. The DNA damage effects of the mice spleen cells induced by the OEs were detected using un-fluorescent staining comet assay. (3) The testis of male mice in the mice bone marrow micronudeus test were taken and the testicular cells were separated . The DNA damage effects on the germ cells induced by the OEs were determined using un-fluorescent staining comet assay. ?Healthy sexual mature Kunming male mice were randomly divided into 6 groups according to the body weight, 6 mice each group. The mice were respectively administrated by peritoneal injection with OEs at the doses of equivalent to 25L/kg, 12.5L/kg, 6.25L/kg, 3.125L/kg water sample, continuously for 5 days. The negative and positive control groups were administrated with DMSO and CP respectively. On the thirtieth day after the last administration, the mice were sacrificed and the frequencies of malformed sperm in the mice were determined. The genital organs’ coefficients of the testis, foreskin gland and spermatophore were calculated and the histopathological changes of testis and prostate were observed using optics microscope. Results: (1) The frequencies of the micronuclei in PCE cells of mice in the 25L/kgand 12.5L/kg groups of the sample A and sample B were significantly higher than those of the negative control group (P<0.01 and P <0.05) and significant dose-response relationships were obtained between the frequencies of the micronuclei and the doses of the OEs (P<0.01), which indicated that some organic mutagens existed in the fishpond water containing sewage. (2) The results of comet assay of mice peripheral blood lymphocytes showed that the tailed-cells rates of each exposure group and the tail’s length of 25L/kg and 12.5L/kg groups of sample A were significantly higher than those of the negative control group (P<0.01). Significant dose-response relationships were obtained between the tailed-cells rates, tail’s length and the doses of sample A (P<0.01). The results of comet assay of mice peripheral blood lymphocytes showed that the tailed-cells rates and tail’s length of 25L/kg and 12.5I7kg groups of sample B were significantly higher than those of the negative control group (iM).Ol). Significant dose-response relationships were obtained between the tailed-cells rates, tail’s length and the doses of sample B (P <0.01). The results indicated that the OEs of sample A and sample B could induce DNA damage on mice peripheral blood lymphocytes. (3) In comparison with the negative control group, there were significant differences in the tailed-cells rates and tail’s length at each OEs treated group of sample A and sample B (P <0.01) . Significant dose-response relationships were obtained between the tailed-cells rates, tail’s length and the doses of sample A and sample B (P <0.01). The results of the comet assay showed that OEs of sample A and sample B could induce DNA damage on mice spleen cells in vitro. (4) The results of comet assay of mice testicular cells showed that the tailed-cells rates and tail’s length of each OEs treated group of sample A and sample B were significantly higher than those of the negative control group (P<0.01). There were significant dose-response relationships between the tailed-cells rates, tail’s更多还原