珠江三角洲地区性癌症生态地球化学研究

发布时间：2018-01-05 22:00

本文关键词：珠江三角洲地区性癌症生态地球化学研究　出处：《中国地质大学(北京)》2017年博士论文　论文类型：学位论文

【摘要】：医学界认为,目前全球性癌症高发,80-90%与环境及职业接触有关。国际癌症研究机构IARC指出“癌症发病和死亡率的地域性特征明显”。因此研究环境因素与癌症之间的关系对防治癌症有重大的意义。本文选取珠江三角洲地区肝癌和鼻咽癌发病率较高的区域作为研究区,本区域多年来环境因素的对癌症的影响作用颇受关注。本文在1:5万土壤生态地球化学详查的基础上,分别从土壤中重金属异常、环境水与饮用水中氨氮特征、亚硝胺的含量等方面分析了研究区内地球化学致癌因子的人为源和自然源,以及地球化学致癌因子行为的影响因素,最后通过与研究区内癌症发病率分布情况相结合,追踪研究区癌症高发的主要地球化学致癌因子。论文取得以下主要成果:1)首次在顺德、四会、中山、佛山等珠江三角洲地区癌症高发区的环境水和饮水中发现普遍存在的直接致癌物质N-亚硝胺化合物。顺德测区水体中亚硝胺的含量最高。15件水样中总N-亚硝胺化合物平均含量为62.9ng/L;其中亚硝基二甲胺(NDMA)平均含量为35.1ng/L,超过国际参考饮水卫生标准(10ng/L)3.5倍。2)NDMA为珠三角地区水体中普遍存在的且含量较高的亚硝胺化合物。其在自来水中含量水平较稳定为22~30ng/L,认为与生产过程加入的含氯消毒剂有关。在自然水体中含量水平差异较大,范围为2.1~114.0ng/L。3)顺德测区地下高铵-胺涌水与人为污染叠加,致N-亚硝胺化合物含量最高,中山、佛山情况类似,显示高铵-污染型亚硝胺组合特征;四会测区工业发展程度相对较低,亚硝胺组合显示为地下水原生型亚硝胺组合特征。4)广西扶绥与珠江三角洲比较,有相似的亚硝胺形成自然条件,但是水体总体污染程度较轻,N-亚硝胺化合物含量较低,其组合接近于地下水原生型亚硝胺组合。5)顺德地区土壤中重金属元素呈强异常富集,形成三个强异常富集区,其富集受到人为污染源和自然源共同影响;其他测区土壤中重金属也有不同程度的富集异常。6)研究区内重金属元素在水土系统中的异常与癌症空间分布没有明显关联;高铵地下水中NH4+、NO2-、NO3-浓度高,为N-亚硝胺的前体物,造成环境及饮用水中直接致癌物质N-亚硝胺化合物的高含量,被认为是研究区内癌症高发的主要地球化学致癌因子。
[Abstract]:The medical profession believes that the current global high incidence of cancer, 80-90% exposure and the environment and occupation. The international agency for research on cancer IARC pointed out that "regional characteristics of cancer incidence and mortality significantly. Therefore research on the relationship between environmental factors and cancer is of great significance to the prevention and treatment of cancer. This paper selects the Pearl River Delta region and the incidence of hepatocellular carcinoma in nasopharyngeal carcinoma high as the study area, the effect on cancer effect the region for many years the environmental factors of popular attention. Based on the 1:5 000 Soil Eco geochemical survey, respectively, from the soil heavy metal anomaly, environmental water and drinking water ammonia characteristics, analyzed the anthropogenic and natural sources in the area of earth chemical carcinogenesis the factor of nitrosamine content, and the influence of the earth chemical carcinogen behavior factors, the incidence of cancer in the study area and distribution With the main geochemical tracing on the area of high incidence of cancer carcinogen. The main conclusions are as follows: 1) for the first time in Shunde, Sihui, Zhongshan, Foshan and other areas in the Pearl River Delta region cancer environment and drinking water found in the direct carcinogenic N- nitrosamine compounds widely exist. The average content of the highest content of.15 water measurement in Shunde water nitrosamines in total N- nitrosamine is 62.9ng/L; the nitroso two methylamine (NDMA) the average content of 35.1ng/L, exceeding the international hygienic standard reference water (10ng/L).2 NDMA) 3.5 times for widespread water in the Pearl River Delta region and the high content of nitrosamine compounds. In the tap water level is stable for 22~30ng/L, associated with chlorine disinfectant production process. The content of adding level differences in natural water, the range of 2.1~114.0ng/L.3) measurement in Shunde underground High ammonium amine inflow and anthropogenic pollution caused by N- overlay, nitrosamine content was the highest in Zhongshan, like the Foshan show amine combination features high ammonium nitrite pollution - type test; Sihui District industrial development level is relatively low, nitrosamine combination showed groundwater native nitrosamines were characteristic of.4) compared with the Pearl River Delta of Guangxi Fusui, a natural condition for the formation of nitrosamines is similar, but the general water pollution to a lesser extent, N- nitrosamine content is low, the combination is close to the original groundwater nitrosamines combination.5) heavy metal elements in soil in Shunde region showed strong enrichment, the formation of three strong the enrichment zone, the enrichment is influenced by anthropogenic sources and natural sources; other area of heavy metals in soil have different degrees of abnormal enrichment of.6) in the research area of heavy metals in soil system abnormalities and cancer have no obvious spatial distribution Correlation; NH4+, NO2- and NO3- concentrations in high ammonium groundwater are high, and N- nitrosamines are precursors, resulting in high content of N- nitrosamines in environment and drinking water. They are considered as the main geochemical carcinogens in the study area.

【学位授予单位】：中国地质大学(北京)
【学位级别】：博士
【学位授予年份】：2017
【分类号】：R730.2;X142

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