南宁市场及邕江鱼类Hg含量研究
发布时间：2018-07-25 12:29
【摘要】：汞作为重金属元素对生物具有危害性,甲基汞对生物危害性更大,水环境中的汞通过生物富集和逐级放大,在鱼体内大量富集。鱼类则是人的食物来源之一,过高的鱼汞含量可使人体造成汞暴露,危害人体健康。民以食为天,随着社会的进步和经济的发展,食品安全问题越来越引起人们的高度关注。南宁作为南方城市,鱼类消费量较大,因此对于市售及邕江鱼类进行汞含量水平进行调查并对通过食用途径汞暴露的安全进行评价有重要的价值。本文以南宁市邕江及各大农贸市场作为研究区域,采用实地调查与实验室分析相结合的方法,运用U.S.EPA 7473 Method并结合DMA-80直接测汞仪,对南宁市10个大型农贸市场的6种淡水鱼类、邕江7个采样点的12种鱼类及11个沿江地点的沉积物中的总汞进行含量测定,完善了实验过程及质量控制,并对鱼类食用风险安全及沉积物潜在生态风险进行了评价。结果表明:1.市场鱼类肌肉总汞含量范围在3.15ng/g~79.71ng/g之间,平均值为19.35ng/g,中值为11.64ng/g。邕江鱼类肌肉总汞含量范围在2.10ng/g~330.56ng/g之间,平均值为44.18ng/g,中值为29.53ng/g。邕江鱼类总汞含量略高于市场鱼类,两者汞含量中值都低于平均值,表明大部分鱼类汞含量水平较低,且两者含量都低于国家规定的食品安全限量中淡水鱼类总汞含量500ng/g,鱼肉总汞含量处于安全范围内。2.邕江水环境中不同营养层级鱼类汞含量排序为:草食性杂食性滤食性鱼类。3.根据体长、重量和含量的相关性分析表明大部分鱼类无显著性相关,市场鱼类只有罗非鱼体长与鱼汞含量呈负相关;邕江鱼类禾花鲤体长与体重与鱼汞含量呈正相关,罗非鱼体重与鱼汞含量呈负相关。4.根据单因子指数法、WHO和FAO每日可接受摄入量PTDIs对鱼肉食用安全进行评价,表明市场及邕江大部分鱼类对人体潜在危害很小,而敏感人群应尽量避免过多摄入鳙鱼、鲢鱼及蓝刀鱼。5.邕江河流沉积物汞含量空间分布特征为东西低,中间高,中游河段流经城区,各类污染物由支流汇入邕江,汞含量以水塘江及八尺江汇入邕江处较高。运用潜在生态指数法,以珠江流域沉积物汞含量平均值作为依据,表明汞在邕江沉积物中的潜在生态风险较小,但水塘江入邕江口沉积物中的汞负荷需要引起足够的重视。总体来说,市售鱼类及邕江水环境中的汞负荷较小,鱼体内汞含量低于国家限定标准,在可食用安全范围内。通过对鱼类产地来源探讨,可否在食品安全方面建立一种产地回溯的机制,当食品质量安全出现问题时,可以通过实验分析手段并结合其它方法来确定受污染食品的来源。
[Abstract]:Mercury, as a heavy metal element, is harmful to organisms, and methylmercury is more harmful to organisms. Mercury in water environment is enriched in large quantities in fish by bioenrichment and step by step amplification. Fish is one of the sources of human food, too high content of fish mercury can cause mercury exposure to human health. With the development of society and economy, people pay more and more attention to food safety. As a southern city, Nanning has a large consumption of fish, so it is of great value to investigate the mercury content of fish sold on the market and Yongjiang River and to evaluate the safety of mercury exposure through food route. In this paper, using Yongjiang River and major farmers' markets in Nanning as the research area, using the method of field investigation and laboratory analysis, using U.S.EPA 7473 Method and DMA-80 direct mercury analyzer, 6 kinds of freshwater fish in 10 large-scale farmers' markets in Nanning were studied. The contents of total mercury in the sediments of 12 species of fish and 11 sites along the Yongjiang River were determined, the experimental process and quality control were improved, and the safety of fish edible risks and potential ecological risks of sediments were evaluated. The result shows that 1: 1. The total mercury content in fish muscle is in the range of 3.15ng/g~79.71ng/g, with an average of 19.35 ng / g and a median value of 11.64 ng / g. The total mercury content in the muscle of Yongjiang fish was in the range of 2.10ng/g~330.56ng/g, with an average of 44.18 ng / g and a median value of 29.53 ng / g. The total mercury content of the fish in Yongjiang River was slightly higher than that of the market fish, and the median mercury content of both fish was lower than the average value, which indicated that the mercury content of most fish was low. Both contents are lower than the total mercury content of freshwater fish (500ng / g), and the total mercury content of fish meat is within the safe range of .2.The total mercury content of freshwater fish is lower than the national food safety limit of 500ng / g. The order of mercury content in different trophic levels of fish in Yongjiang River was: herbivorous, omnivorous, filter feeding fish. According to the correlation analysis of body length, weight and content, there was no significant correlation between body length and mercury content in most fishes, only tilapia had a negative correlation with mercury content in fish in the market, and there was a positive correlation between body length and body weight and mercury content in fish in Yongjiang River. There was a negative correlation between body weight and mercury content in tilapia. According to the single factor index method and the daily acceptable intake of FAO and PTDIs, the food safety of fish was evaluated. The results showed that most of the fish in the market and the Yongjiang River had little potential harm to human body, and the sensitive population should avoid excessive intake of bighead carp as far as possible. Silver carp and blue saber. The spatial distribution of mercury content in the sediments of the Yongjiang River is low in the east and west, high in the middle. The middle reaches of the river flow through the urban area, and all kinds of pollutants flow from the tributaries to the Yongjiang River. The mercury content in the Yongjiang River is higher in the reservoirs and the Bazhijiang rivers. Based on the average mercury content in sediments of the Pearl River basin, the potential ecological risk of mercury in the sediments of Yongjiang River is relatively small, but the mercury load in the sediments from the Yongjiang River estuary should be paid more attention to. In general, the mercury load in the market fish and Yongjiang river water environment is relatively small, and the mercury content in fish is lower than the national standard, which is within the safe range of edible. By discussing the origin of fish, we can establish a kind of backtracking mechanism in food safety. When food quality and safety problems occur, we can determine the source of contaminated food by means of experimental analysis and other methods.
【学位授予单位】：广西师范学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TS254.7;X56
本文编号：2143827
[Abstract]:Mercury, as a heavy metal element, is harmful to organisms, and methylmercury is more harmful to organisms. Mercury in water environment is enriched in large quantities in fish by bioenrichment and step by step amplification. Fish is one of the sources of human food, too high content of fish mercury can cause mercury exposure to human health. With the development of society and economy, people pay more and more attention to food safety. As a southern city, Nanning has a large consumption of fish, so it is of great value to investigate the mercury content of fish sold on the market and Yongjiang River and to evaluate the safety of mercury exposure through food route. In this paper, using Yongjiang River and major farmers' markets in Nanning as the research area, using the method of field investigation and laboratory analysis, using U.S.EPA 7473 Method and DMA-80 direct mercury analyzer, 6 kinds of freshwater fish in 10 large-scale farmers' markets in Nanning were studied. The contents of total mercury in the sediments of 12 species of fish and 11 sites along the Yongjiang River were determined, the experimental process and quality control were improved, and the safety of fish edible risks and potential ecological risks of sediments were evaluated. The result shows that 1: 1. The total mercury content in fish muscle is in the range of 3.15ng/g~79.71ng/g, with an average of 19.35 ng / g and a median value of 11.64 ng / g. The total mercury content in the muscle of Yongjiang fish was in the range of 2.10ng/g~330.56ng/g, with an average of 44.18 ng / g and a median value of 29.53 ng / g. The total mercury content of the fish in Yongjiang River was slightly higher than that of the market fish, and the median mercury content of both fish was lower than the average value, which indicated that the mercury content of most fish was low. Both contents are lower than the total mercury content of freshwater fish (500ng / g), and the total mercury content of fish meat is within the safe range of .2.The total mercury content of freshwater fish is lower than the national food safety limit of 500ng / g. The order of mercury content in different trophic levels of fish in Yongjiang River was: herbivorous, omnivorous, filter feeding fish. According to the correlation analysis of body length, weight and content, there was no significant correlation between body length and mercury content in most fishes, only tilapia had a negative correlation with mercury content in fish in the market, and there was a positive correlation between body length and body weight and mercury content in fish in Yongjiang River. There was a negative correlation between body weight and mercury content in tilapia. According to the single factor index method and the daily acceptable intake of FAO and PTDIs, the food safety of fish was evaluated. The results showed that most of the fish in the market and the Yongjiang River had little potential harm to human body, and the sensitive population should avoid excessive intake of bighead carp as far as possible. Silver carp and blue saber. The spatial distribution of mercury content in the sediments of the Yongjiang River is low in the east and west, high in the middle. The middle reaches of the river flow through the urban area, and all kinds of pollutants flow from the tributaries to the Yongjiang River. The mercury content in the Yongjiang River is higher in the reservoirs and the Bazhijiang rivers. Based on the average mercury content in sediments of the Pearl River basin, the potential ecological risk of mercury in the sediments of Yongjiang River is relatively small, but the mercury load in the sediments from the Yongjiang River estuary should be paid more attention to. In general, the mercury load in the market fish and Yongjiang river water environment is relatively small, and the mercury content in fish is lower than the national standard, which is within the safe range of edible. By discussing the origin of fish, we can establish a kind of backtracking mechanism in food safety. When food quality and safety problems occur, we can determine the source of contaminated food by means of experimental analysis and other methods.
【学位授予单位】：广西师范学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TS254.7;X56
【相似文献】
相关期刊论文 前2条
1 吴宁远,孙卫国,高建萍;呼市部分地区牛奶中Cd、Pb、Hg含量的测定[J];内蒙古科技与经济;1999年S2期
2 ;[J];;年期
相关硕士学位论文 前1条
1 曹宁;南宁市场及邕江鱼类Hg含量研究[D];广西师范学院;2015年
，本文编号：2143827
本文链接：https://www.wllwen.com/kejilunwen/huanjinggongchenglunwen/2143827.html
最近更新
教材专著
