广西北部湾典型经济贝类重金属污染及影响因素分析

发布时间：2018-05-22 13:20

本文选题：北部湾 + 贝类　；参考：《广西师范学院》2017年硕士论文

【摘要】：随着广西北部湾经济圈工农业的快速发展,重金属对环境特别是对水体的污染问题越来越严重。贝类对水体重金属有较强的吸附积累能力,因而极易超标引发食品安全问题。本研究于2014年9月至2015年11月采集广西北部湾东兴、防城港、钦州、北海、涠洲岛近岸贝类,分析重金属Zn、Cu、Pb、Cd、Cr、Hg、As含量,参考《食品安全国家标准食品中污染物限量》(GB 2762-2012)、《无公害食品水产品有毒有害物质限量》(NY 5073-2006)和澳大利亚食品标准法规,采用单因子指数法和膳食暴露评估法对贝类中的重金属污染情况进行了评价,旨在弄清北部湾近岸海域贝类的重金属污染状况,分析贝类重金属污染含量,及在不同品种、季节、产地的分布规律,探讨影响其含量的环境因素。结果如下:广西北部湾近岸海域养殖区主要经济贝类重金属污染状况不容乐观,样品中合格率仅为40.15%,重金属超标元素为Zn、Cu、Cd、As,超标率分别为0.75%、7.58%、7.30%、49.24%,其中As污染情况严重,亟需加强As污染监控。单因子贝类生物质量评价表明近江牡蛎消化腺Cu、Cr,毛蚶消化腺Zn、Cd、As,旗江珧消化腺Zn的污染因子质量指数1,为保证食用安全,建议去除上述贝类消化腺后食用。膳食暴露评估方法显示各重金属膳食摄入量对人类食用安全尚未构成威胁,但是Cd和As含量富集较为明显,需加强对以上两种元素的监测。贝类对重金属的积累存在种间差异,近江牡蛎对Zn、Cu有较高的富集能力,旗江珧、华贵栉孔扇贝、紫贻贝较易富集Cd,大竹蛏、短竹蛏、翡翠贻贝、斧形胡桃蛤、旗江珧、施氏獭蛤、衣蚶蜊、紫贻贝积累As较严重。广西北部湾典型经济贝类重金属含量呈现一定季节与地理分布特征。近江牡蛎Zn、Cu与旗江珧Zn含量春夏季较高,秋冬季较低;华贵栉孔扇贝、旗江珧Cd含量秋季较高;波纹巴非蛤、近江牡蛎、旗江珧、华贵栉孔扇贝、琴文蛤Cr、Hg含量冬季较高;波纹巴非蛤、近江牡蛎、旗江珧、华贵栉孔扇贝、琴文蛤As含量夏季高,秋季低;Pb含量未显现明显季节分布特征。总体而言,钦州与北海贝类重金属污染严重,涠洲岛、防城港、东兴的贝类污染较轻。贝类养殖的海水环境会影响贝类积累重金属的富集程度。相关性结果显示贝类生活的环境因子影响贝类对重金属的吸收,表现为贝类体内的Zn、Cu含量与海水中的Zn、Cu浓度呈正相关,与盐度呈负相关,而与水温、pH、溶解氧没有相关性。
[Abstract]:With the rapid development of industry and agriculture in the Beibu Gulf Economic Circle of Guangxi, the pollution of heavy metals to the environment, especially to the water body, is becoming more and more serious. Shellfish have a strong ability to adsorb and accumulate heavy metals in water, which can easily lead to food safety problems. This study collected shellfish from Dongxing, Fangchenggang, Qinzhou, Beihai and Weizhou Island of Guangxi from September 2014 to November 2015. Reference is made to the National Food Safety Standard for Food contamination limits (GB 2762-2012C), the limits of noxious and harmful substances in Aquatic products of Non-Pollutant Food products (NNY 5073-2006) and the Australian Food Standards and regulations, The pollution of heavy metals in shellfish was evaluated by single factor index method and dietary exposure assessment method in order to find out the pollution status of heavy metals in shellfish in the coastal waters of Beibu Gulf, to analyze the pollution content of heavy metals in shellfish, and to analyze the pollution of heavy metals in different species. The distribution law of season and origin and the environmental factors affecting its content were discussed. The results are as follows: the pollution of heavy metals in the main economic shellfish is not optimistic. The qualified rate of heavy metals in the samples is only 40.15, and the excess heavy metals are Zn ~ (2 +) Cu ~ (2 +) CD ~ (2 +) as, and the excess rates are 0.75 ~ 7.58 ~ 7.30 ~ (7.30) and 49.24% respectively, among which, the pollution of as is serious. It is urgent to strengthen as pollution monitoring. The biological quality evaluation of single factor shellfish showed that the pollution factor quality index of the digestive gland of oyster, Cryptomonas subcrenata and Pinna pinna was 1. In order to ensure the safety of edible, it was suggested to remove the digestive glands of the shellfish and eat them. Dietary exposure assessment showed that the dietary intake of heavy metals did not pose a threat to human food safety, but the concentration of CD and as was obvious, so it was necessary to strengthen the monitoring of the above two elements. The accumulation of heavy metals in shellfish varied from species to species. Oyster near the river had higher enrichment ability to Zn and Cu. Pinna flagellata, scallop farreri, mussel, mussel clam, mussel emeralds, clam axillaris and Pinna pinna were easy to enrich. Shih otter clam, Mytilus mussels accumulated as more serious. The heavy metal contents of typical economic shellfish in Beibu Gulf of Guangxi show seasonal and geographical distribution characteristics. The Zn contents of Zn-Cu and Pinna pinna were higher in spring and summer, lower in autumn and winter, higher in autumn and autumn in chlamys farreri, higher in CD in autumn, higher in bafeiclam, oyster, Pinna pinata, chlamys farreri and Cr-Hg in winter. The contents of as were higher in summer, lower in autumn and lower in autumn, but the seasonal distribution characteristics were not obvious. The contents of Bafeiclam, oyster, pinna, scallop, scallop and clam were high in summer and low in autumn. In general, the pollution of heavy metals in Qinzhou and Beihai shellfish is serious, and the pollution of shellfish in Weizhou Island, Fangcheng Port and Dongxing is lighter. The marine environment of shellfish culture will affect the accumulation of heavy metals in shellfish. The results showed that the environmental factors of shellfish life affected the absorption of heavy metals by shellfish. The results showed that the content of Zn ~ (2 +) Cu in shellfish was positively correlated with the concentration of Zn ~ (2 +) Cu in seawater, and negatively correlated with salinity, but had no correlation with water temperature, pH and dissolved oxygen.
【学位授予单位】：广西师范学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X55

【参考文献】