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1.
Abstract

This study reports the concentrations of total mercury and methyl mercury in sixteen families of marine biota caught off the coast of Kasimedu in Chennai, India, an important but understudied fish landing region. These included the commonly caught croakers, carangids, rays, goat fish, anchovies, crabs, and prawns. There was no correlation between total mercury or methyl mercury with fish length or mass. All concentrations were lower than the Food Safety and Standards Authority of India limits (total mercury = 500?μg/kg; methyl mercury = 250?μg/kg). Some values were above screening levels (total mercury >40?μg/kg wet weight) when considering possible adverse effects in predatory fish that consume the analyzed biota.

Abbreviations: dw: dry weight; MeHg: methyl mercury; THg: total mercury; ww: wet weight  相似文献   
2.
在北黄海近岸海域21个典型区域采集了可构成3个营养级的6种生物样品,分别为海带、裙带菜、牡蛎、扇贝、海参和黑鱼.采用HPLC-MS/MS检测6种生物样品中双酚A(BPA)、辛基酚(0P)、壬基酚(NP)、2,4-二氯酚(2,4-DCP)、对叔丁基苯酚(PTBP)和对特辛基苯酚(POP)质量比,并进一步采用生物富集因子(BAF)和生物放大因子(TMF)评价了北黄海近岸海域生物体内酚类内分泌干扰物的富集作用与放大能力.结果表明,北黄海近岸海域生物体中6种酚类内分泌干扰物的质量比范围为检出限(nd)~1 796.26 ng/g,其中2,4-二氯酚具有较强的生物富集效应,辛基酚和壬基酚具有潜在的生物富集效应,同时营养级越高,生物放大作用越明显.研究表明,海洋生物体对酚类内分泌干扰物的富集能力随营养级升高而增大.  相似文献   
3.
Cu, Cr, Mn, Ni and Zn contents were quantified for three wild-growing edible species of macrofungi (Boletus edulis, Macrolepiota procera and Cantharellus cibarius) and underlying soil samples collected at forest sites in Lubuskie voivodeship, Poland. The total concentration of the analysed elements was determined using an ASA iCE 3000 series atomic absorption spectrometer. The analysis found significant differences in bioaccumulation between species and differing distributions of trace elements in the caps and stalks of fruiting bodies. Bioaccumulation factors revealed that Zn and Cu are the most bioaccumulated elements, whereas Cr and Mn are excluded from bioaccumulation. Macrolepiota procera showed the highest bioaccumulation of Cu, and Zn is accumulated to the greatest extent by Boletus edulis. A few significant differences (p≤0.05) between the examined species were observed.  相似文献   
4.
卤系阻燃剂在东江鱼体中的生物富集   总被引:1,自引:0,他引:1  
准确获取化合物的生物富集因子(BAF)对于判定化合物是否属于潜在毒害性污染物、评价其生态环境风险都具有重要的意义.本文以东江水体为研究区域,以PBDEs、DBDPE、DP、TBBPA和HBCDs为目标化合物,研究了其在3种鱼体中的富集特征.结果表明,5种化合物的lg BAF的变化范围分别为5.0~7.4、6.1~7.1、4.6~7.9、2.6~4.6和4.8~7.7.在本研究中,大多的化合物lg BAF值均大于3.7,说明这些污染物都具有生物富集能力.HFRs的BAF值总体随着lg Kow值的增加而增加,但当lg Kow7时,生物对PBDEs的生物富集能力有所下降.γ-HBCD向α-HBCD的生物转化以及生物体对BDE66和BDE99的代谢导致这几种单体偏离了这个模型预测趋势.DBDPE的BAF值大于BDE209的BAF值,作为大分子污染物,DBDPE的生物富集能力应该值得关注.通过对污染物的生物沉积物富集因子(BSAF)的计算,发现绝大多数的污染物的BSAF值均小于1,表明沉积物不太可能作为水生生物的污染源.  相似文献   
5.
Abstract

Earlier papers indicated that the first incident of green discoloration in oysters (Crassostrea gigas) and the mass mortality observed in 1986 along the Taiwan Erhjin Chi coastal area were caused by the higher contents of total copper and copper species (mainly bioavailable and free ion) in sea water. the copper in sea water would be sorbed by suspended matter and transferred to sediments, and the copper in the sediments would also be desorbed to sea water. Processes of copper adsorption and desorption are the major factors influencing the contents of total copper and copper species in sea water and sediments. in this study, the Erhjin Chi sediments were mixed with sea water by a shaker technique. When the mixture was shaken for one hour, analogous to tidal mixing in estuaries, only copper desorption from sediments was observed. If the shaking time is increased for more than 3 hours, the copper released from the sediments was resorbed to the remaining solid phases. the higher the contents of mud (91.71%) and total copper (701 mg kg?1) in sediments, the higher the copper desorption rate (1.86 ppm hr?1) and copper adsorption rate (0.50 ppm hr?1) were observed. in sediments containing lower mud (0.80%) and lower copper (43.5 mg kg?1), the copper desorption and adsorption rates were 0.83 ppm hr?1 and 0.22 ppm hr?1, respectively. the interactions among the total copper and copper species in sea water and sediments, chemical and ecological parameters, and copper bioaccumulation in oysters in the Erhjin Chi estuarine and coastal area are also discussed.  相似文献   
6.
Heavy metal distribution in medicinal plants is gaining importance not only as an alternative medicine, but also for possible concern due to effects of metal toxicity. The present study has been focused on emphasizing the heavy metal status and bioaccumulation factors of V, Mn, Fe, Co, Cu, Zn, Se (essential metals) and Cr, Ni, Cd, As and Pb (potentially toxic metals) in medicinal plants grown under two different environmental conditions e.g., near to Khetri copper mine and those in fertile soils of Haridwar, both in India, using Instrumental Neutron Activation Analysis (relative method) and Atomic Absorption Spectrometry. The copper levels in the medicinal plants from Khetri were found to be 3-4 folds higher (31.6–76.5 mg kg?1) than those from Haridwar samples (7.40–15.3 mg kg?1), which is correlated with very high copper levels (763 mg kg?1) in Khetri soil. Among various heavy metals, Cr (2.60–5.92 mg kg?1), Cd (1.47–2.97 mg kg?1) and Pb (3.97–6.63 mg kg?1) are also higher in concentration in the medicinal plants from Khetri. The essential metals like Mn (36.4–69.3 mg kg?1), Fe (192–601 mg kg?1), Zn (24.9–49.9 mg kg?1) and Se (0.13–0.91 mg kg?1) and potentially toxic metals like Ni (3.09–9.01 mg kg?1) and As (0.41–2.09 mg kg?1) did not show much variations in concentration in the medicinal plants from both Khetri and Haridwar. The medicinal plants from Khetri, e.g., Ocimum sanctum, Cassia fistula, Withania somnifera and Azadirachta Indica were found rich in Ca and Mg contents while Aloe barbadensis showed moderately high Ca and Mg. Higher levels of Ca-Mg were found to correlate with Zn (except Azadirachta Indica). The bioaccumulation factors (BAFS) of the heavy metals were estimated to understand the soil-to-plant transfer pattern of the heavy metals. Significantly lower BAF values of Cu and Cr were found in the medicinal plants from Khetri, indicating majority fraction of these metals are precipitated and were immobilized species unsuitable for plant uptake. Overall, Withania somnifera (Ashwagandha) showed very high metal bioaccumulation.  相似文献   
7.
The potential of kenaf (Hibiscus cannabinus L.) for phytoremediation of lead (Pb) on sand tailings was investigated.A pot experiment employing factorial design with two main effects of fertilizer and lead was conducted in a nursery using sand tailings from an ex-tin mine as the growing medium.Results showed that Pb was found in the root,stem,and seed capsule of kenaf but not in the leaf.Application of organic fertilizer promoted greater biomass yield as well as higher accumulation capacity of Pb.In Pb-spike...  相似文献   
8.
城市交通大气与土壤重金属对小蜡生物富集作用的影响   总被引:4,自引:2,他引:2  
选择合肥市区交通干道、城郊公路和森林公园作为具有不同交通流量的路段,通过火焰原子吸收法,测定土壤和小蜡叶片中的w(Cu),w(Zn),w(Pb),w(Cd)和w(Cr);运用统计方法研究土壤和小蜡叶片中重金属含量的差异和相关性,以及与城市交通大气污染的关系.结果表明:市区交通干线和城郊公路的土壤中w(Cu),w(Zn),w(Pb),w(Cd)和w(Cr)均高于对照点(森林公园),且市区交通干线与对照点的土壤中重金属含量差异显著;小蜡叶片对5种重金属富集量与土壤中的相应重金属含量没有明显相关性,这表明叶片富集的重金属主要来源于道路交通产生的大气重金属污染物,而非主要从土壤中吸收获得;小蜡叶片对大气中的Pb和Cr的富集能力较强,其生物浓缩系数分别为5.50和3.43,说明小蜡可能是Pb和Cr的良好指示植物,可用于环境监测.  相似文献   
9.
多氯代二苯并-对-二噁的微生物降解   总被引:6,自引:0,他引:6  
从多氯代二苯并-对-二噁(PCDDs)污染的土壤和含氧沉积物中分离筛选出8株降解PCDDs的菌株,均能以一氯代和二氯代二为单一碳源和能源生长并使其降解,多数几乎不能降解三氯代二噁.但是,用邻二氯苯作为初级营养共代谢物,可以增强菌株对较高氯代二噁(如三氯代和四氯代二噁)的降解能力.利用所筛选菌株中的1株,经鉴定为假单胞菌EE41(Pseudomonas sp.EE41).降解试验结果表明,1,2,3-TrCDD在浓度为1.2mg/L时3周内可降解33%,2,3,7,8-TCDD在0.1 mg/L时3周内最多可降解37.8%.试验的高氯代二噁(pCDD,H6-CDD,H7-CDD和OCDD)则只被菌体强烈吸收并积累,却不能被降解.  相似文献   
10.
超富集植物在营养元素生物强化及重金属污染植物修复技术领域有重大应用前景。通过野外调查和栽培实验,研究了碎米荠植物对硒镉的吸收富集特征。研究表明:野生碎米荠中Se含量达数百mg/kg,叶片中Se最高含量为1 365 mg/kg。地上部Se的生物富集系数在2.8~43.8的范围内,大部分超过10;生物转移系数在0.46~1.88之间,大部分大于1。地上部Cd含量都超过了100 mg/kg,叶中的Cd含量大部分在400~800 mg/kg之间。富集系数都大于1,且农田及小溪流域植株地上部Cd的生物富集系数高达几十甚至上百,Cd的生物转移系数大部分超过1。露天栽培条件下,碎米荠中的硒镉含量随盆栽土壤中硒镉浓度的上升呈现出先增加后降低的特征,当Se含量为50 mg/kg时植物中的Se含量最高,此时地上部Se含量为995 mg/kg,地下部Se含量1 100 mg/kg。当Cd浓度为80 mg/kg时,植株当中Cd含量最高,地上部和地下部中的Cd含量分别高达550 mg/kg、337 mg/kg。研究认为湖北渔塘坝发育的碎米荠植物是硒镉多元素超富集植物,在硒镉生态环境污染修复方面具有重大应用前景。  相似文献   
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