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41.
Heavy Metal Monitoring Using Bivalved Shellfish from Zhejiang Coastal Waters, East China Sea 总被引:2,自引:0,他引:2
The interest of culturing bivalved shellfish (including mussels, clams, oysters etc.), has increased in recent years, but
the consumption has been hampered both by high levels of heavy metals and toxic algae. The levels of heavy metals (Hg, Cd,
Pb, Zn, Cu and As) were determined in soft tissues of different shellfish from Zhejiang coastal waters, East China Sea. The
average concentrations of the heavy metals analyzed exhibited the following decreasing order: Zn > Cu > As > Cd > Pb > Hg.
Comparison of heavy metals concentrations among species indicated that Bivalves clearly have significant potential as useful
bioindicators; however, the results indicated that no one species is universally suitable, as is true of any organism used
in these studies. The distribution of the metals was also investigated along the Zhejiang coast, which the results showed
the mean concentration of Hg and Cd detected did not vary greatly and presented a similar spatial pattern at different sampling
stations, the concentrations of Zn and Pb were highly variable at different sampling sites. The amounts of heavy metals in
soft tissue of shellfish were also compared with those from the related species from other seas in China and world marine
waters. The results suggested that the coastal area might be considered relatively unpolluted with heavy metals and the concentrations
of metals in shellfish also below the seafood safety limits for human consumption. 相似文献
42.
Mengmeng Guo Guanchao Zheng Jixing Peng Di Meng Haiyan Wu 《Journal of environmental science and health. Part. B》2019,54(4):271-280
Perfluorinated alkyl substances (PFASs) are emerging persistent organic pollutants, which pose a threat to human health primarily by dietary exposure, especially through seafood. Bohai Sea (a semi-closed sea located north of China) is an important shellfish aquaculture area that is possibly highly-polluted with PFASs. In this study, we first evaluated contamination by PFASs in a total of 230 samples of marine shellfish from the Bohai Sea. Samples included five important shellfish species, collected from important aquaculture spots distributed around the Bohai Sea. Samples were analyzed by an ultra-fast liquid chromatography-tandem mass spectrometry method, which could simultaneously detect 23 PFASs in shellfish. Our research verified that PFASs have become a threat to the safety of shellfish products in this area. Furthermore, contamination by PFASs in shellfish changed depending on the components of PFASs, the species of shellfish, and the sampling sites. Many of the 23 target compounds contributed to the high detection ratio (>50%) as follows: perfluorooctanoic acid (PFOA)?>?perfluorononanoic acid?>?perfluorodecanesulfonic acid?>?perfluorooctanesulfonic acid (PFOS). Compared with other dominant components, PFOA not only had the highest detection percentage in shellfish samples (98.3%), but its detection level contributed to 87.2% of total PFASs concentrations, indicating that PFOA is the major threat to the safety of shellfish products. The highest level of PFAS was found in clams (62.5?ng?g?1 wet weight of PFOA). The concentration of total PFAS in different shellfish species showed the following trend: clams?>?mussels?>?scallops?>?whelks?>?oysters. The maximum concentration of total PFAS or PFOA was found in Shouguang. The total concentration of PFOS and its precursor were highest in Cangzhou, possibly due to local industrial activities. The results presented in this paper provide new data on the contamination of marine shellfish along the Bohai Sea coasts in China, and constitute a reference for future monitoring of contamination by emerging contaminants in Bohai coast. 相似文献
43.
江苏如东贝类养殖区重金属的含量分布特征及潜在生态风险评价 总被引:3,自引:0,他引:3
根据2010年3月(冬季)、5月(春季)、8月(夏季)、11月(秋季)对江苏省如东县贝类养殖区4次现场监测资料,着重对养殖区海水和表层沉积物中重金属的分布特征进行了分析,并对养殖区进行了生态环境质量评价及潜在生态风险评价。结果表明:海水中重金属污染程度顺序为Pb>Zn>Hg>Cu>As>Cd;表层沉积物中重金属的污染程度顺序依次为Zn>Pb>As>Cu>Hg>Cd;表层沉积物中重金属的潜在生态危害程度顺序依次为Hg>Cd>As>Pb>Cu>Zn。4次调查结果的多种重金属的潜在生态风险指数(RI)均低于140,表明这些重金属对海洋生态系统的潜在生态风险属于低潜在生态风险水平,养殖环境良好。 相似文献
44.
江苏如东滩涂贝类养殖区表层沉积物中重金属来源分析及其潜在生物毒性 总被引:8,自引:4,他引:4
通过2010年对江苏如东滩涂贝类养殖区表层沉积物中重金属Cu、Zn、Pb、Cd、Hg、As含量的调查分析,应用地质累积指数(index of geo-accumulation,Igeo)对各重金元素的污染状况进行了评价,结果表明重金属污染可分为3类:Cu、Cd、Hg为无污染;Pb、As为中~无污染;Zn为中度污染,重金属污染程度顺序为Zn>As>Pb>Cd>Cu>Hg.根据沉积物质量基准(sediment quality guideline,SQG),表层沉积物中Cd、As的含量在各采样站位分别表现为无潜在生物毒性效应,偶尔有潜在生物毒性效应,Cu、Pb、Zn、Hg的含量则在部分采样站位偶尔有潜在生物毒性效应,其中仅有Zn在部分采样站位有频繁发生的潜在生物毒性效应.毒性单位评价(toxic unit,TU)结果表明,仅有1个采样站位具有明显的急性毒性,其余站位无急性生物毒性效应.主成分分析(principal component analysis,PCA)的结果表明,前2个主成分的贡献率分别为37.56%、33.71%,揭示了重金属污染主要有2个来源:工业点源排污和交通航运污染源. 相似文献
45.
46.
Results of surveys on Polychlorinated biphenyls (PCB) and organochlorine insecticides (HCH and DDT) in fish and shellfish from Lake Biwa were summarized from 1987 to 1996. In 1975, fish and shellfish in Lake Biwa were highly contaminated with PCB, HCH and DDT but recently in 1992–1996 the concentrations of these chemicals were very low and nearly constant. In the composition of HCH isomers, β‐HCH was dominant in all kinds of fish and shellfish. In the composition of DDT and DDT metabolites, pp'‐DDE was similarly dominant in all kinds of fish and shellfish. Further, the data in Lake Biwa were compared with those in Lake Michigan and Lake Baikal. 相似文献
47.
渤、黄海沿岸几种经济贝类及其生存环境中的粪大肠菌群 总被引:1,自引:0,他引:1
报道了渤、黄海 6个重点沿岸海域 (吕泗、青岛、北戴河、盘锦、大连和庄河 )表层海水和几种经济贝类中的粪大肠菌群 (FC)检测结果。结果表明 ,16个表层海水样品中的FC含量波动范围为 <4 0~≥ 4 80 0 0 /L。 36个经济贝类样品中的FC数为 <2~≥ 2 4 0 0 /g鲜重。上述结果说明 ,渤、黄海某些重点沿岸海域 (如青岛、北戴河沿岸 )受人畜粪便等生活污水和人为活动影响较严重 ,海域环境卫生状况不容乐观 ,需加强规划和治理力度。 相似文献
48.
作者借助于卫星CCT数据进行了人-机对话式信息比值处理,获取了河口区高浓度的悬浮泥沙涡旋水体信息,并与现场考察资料相对证,发现其有规律的出现与输移。为此,结合毛蚶的生活习性,确认黄河入海泥沙扩散对黄河口及其邻近水域毛蚶的资源分布有直接的影响。预测了未来20年内研究区毛蚶场的扩大趋势及其范围。 相似文献
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50.
广东沿海麻痹性贝毒素的地理分布特征 总被引:2,自引:0,他引:2
对采自2001年和2002年10~11月间的广东省近岸海域15个地点的翡翠贻贝样品,用Oshima麻痹性贝类毒素高效液相色谱法进行主要毒素成份分析。结果显示:高毒性毒素成分STX、GTX1检出率较低,而低毒性毒素成分C1、C2、GTX5及中等毒性毒素成分GTX3、GTX4检出率较高;各主要毒素成分在地区间存在一些差异;与2001年相比,2002年各主要毒素成分的检出率和检出的毒素含量值有所降低,消化腺在这方面变化尤其明显;不论消化腺或壳内全部软组织,其PSP毒性的平均值,存在明显的地理分布差异,大亚湾、大鹏湾海域〉深圳湾、珠海海域和粤东海域〉粤西海域。 相似文献