Spatial variations of heavy metals contamination in sediments from Odiel river (Southwest Spain)

The presence of heavy metal concentrations was examined in surface sediments from 27 sites within the Odiel river in the southwest Spain suffering inputs from industrial and mining activities. The interest is specially focused on the final delta located in the Odiel Natural Park, which constitutes a feeding ground of international importance for migrating birds. The behavior of 10 heavy metals (Zn, Cd, Pb, Cu, Cr, Mn, Ni, Fe, Hg) is conditioned by chemical properties of sediments such as acidity and carbonate or the presence of sulfate Very acidic sediments in the medium course of river contribute to the lower presence of metal as a consequence of leaching process. However, tidal action raises the pH in the marshes of the delta with correlative metal accumulation. In accordance with the Müller [Umschan 79 (1979) 133-149] scale for geoaccumulation index, the entire watercourse could be considered polluted by Zn and Pb, while Cu exhibits a high presence in the delta marshes of the river.     

鄱阳湖表层沉积物中砷及重金属赋存形态及其潜在生态风险

重金属污染是水体沉积物污染的主要问题之一,研究沉积物中重金属元素的赋存形态,探索水体中重金属的来源,可以为水体重金属污染治理修复提供理论基础。采用BCR三步连续提取法对鄱阳湖枯水期表层沉积物中As和7种重金属元素（Cd、Co、Cr、Cu、Ni、Pb和Zn）的赋存形态进行了研究,并基于重金属风险评价代码（Risk Assessment Code, RAC）方法评估了鄱阳湖表层沉积物中的As和7种重金属元素的潜在生态风险。结果表明,鄱阳湖表层沉积物中As、Co、Cr、Cu、Ni和Zn主要以残渣态的形式存在(6160%~8518%);Pb主要以残渣态（5097%）和铁锰氧化物结合态（4102%）为主要的赋存形态,其可提取态所占比例为4903%,具有较高的二次释放潜力;Cd的赋存形态主要以弱酸提取态（4160%）和铁锰氧化态（2719%）为主,其可提取态所占比例高达7749%,潜在生态风险较大。RAC分析结果表明,鄱阳湖表层沉积物Cd的生态风险整体上位于高风险,需要加强对鄱阳湖Cd污染的关注。所有站点Cr的弱酸提取态所占比例均低于1%,表明鄱阳湖Cr污染的生态风险为无风险,As、Ni和Pb属于低风险,而Cu、Co和Zn位于低风险至中等风险     

Heavy metals in water, sediments, plants and fish of Kali Nadi U.P. (India)

The distribution of heavy metals viz., Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water, sediments, plants and fish samples collected from the Kali Nadi (India) have been determined. The studies have shown that there was considerable variation in the concentration of heavy metals from one sampling station to the other which may be due to the variation in the quality of industrial and sewage wastes being added to the river at different places. The orders of the concentration of heavy metals in water, sediments, plants (Eicchornia crassipes) and fish (Heteropnuestes fossilis) were Fe > Zn > Cu > Mn > Cr > Ni > Pb > Co > Cd; Fe > Zn > Mn > Ni > Cr > Co > Cu > Pb > Cd; Fe > Mn > Zn > Cu > Ni > Co > Pb > Cr > Cd and Fe > Zn > Mn > Ni > Pb > Co > Cr > Cu > Cd, respectively.     

Speciation of heavy metals in marine sediments from the East China Sea by ICP-MS with sequential extraction

Twelve elements (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, Cd and Pb) in 24 sediment samples at eight sites (S1-S8) from the East China Sea were analyzed with the BCR sequential extraction (SE) protocol to obtain the metal distribution patterns in this region. The results showed that the heavy metal pollutions in S4 and S8 were more severe than in other sampling sites, especially Cd and Pb pollution. In the top sediments at S4 and S8, both the total contents and the most dangerous non-residual fractions of Cd and Pb were extremely high. More than 90% of the total concentrations of V, Cr, Mo and Sn existed in the residual fraction. Fe, Co, Ni, Cu and Zn mainly (more than 60%) occurred in the residual fraction. While Mn, Pb and Cd dominantly presented in the non-residual fractions in the top sediments. The metal distribution patterns with depth and the correlations between total organic carbon (TOC) and the total Fe-Mn content were also investigated. The results showed that, for most of the elements except Fe, the concentration of elements in fraction A in the top sediments was higher than that in other depth. The similar rule was also found in fraction B but not in fraction C. Besides, the distributions of V, Cd in fraction B and Pb, Cd, Cu in fraction C might be affected by TOC.     

Heavy metals in organisms and sediments from Turkish Coast of the Black Sea, 1997-1998

During the period 1997-1998, macroalgae, sea snail, mussel, fish and sediment samples were collected at different stations of the Turkish Black Sea coast in order to establish the concentration of selected heavy metals. Heavy metals analyzed were Cd, Co, Cr, Ni, Zn, Fe, Mn, Pb and Cu. The results showed that the Turkish Black Sea coast is facing heavy metal pollution. The metal concentrations in macroalgae, sea snail, mussel and sediment samples are very high. However, Cd, Pb and Cu concentrations in anchovy fish decreased, while Co, Fe, Zn, Cr, Mn and Ni contents had changed when compared previous data. The metal levels in macroalgae did not follow the same pattern as concentrations in sediments at the same station. On the other hand, concentrations of Cd, Co, Cr, Zn, Fe, Mn and Cu in sea snail, mussel and fish samples were related to sediment data in the examined stations.     

Heavy metals in fish (Solea vulgaris, Anguilla anguilla and Liza aurata) from salt marshes on the southern Atlantic coast of Spain

Comparisons were made of metal concentrations in water and sediment with those in the muscle and livers of three species of fish caught in four seawater reservoirs (two in the Odiel estuary and two in the Bay of Cádiz). The concentrations of a large number of metals in the water, sediment and fish were higher in the Odiel reservoirs than in those in Cádiz. We found high metal-enrichment factors in the livers as compared to muscle (over 100 for Fe and Cu and around 5 for Zn, Ni, Cd and Pb). The three fish species showed differences in metal content. For example, eels accumulated more metals in muscle and grey mullet in the liver. The metal levels found in muscle in the three species were below the legal limits for human consumption, although Cu in the liver was above the limit in the three species taken from the Odiel reservoirs, and Zn levels in liver were over the maximum in eels from one of the Odiel marshes. Significant correlations (p<0.05) were obtained for the levels of numerous metals in water, sediment and fish.     

Speciation of elements in sediment samples collected at lakes Volvi and Koronia, N. Greece

A five-step sequential extraction procedure was applied for the determination of the distribution of seven elements (Cd, Pb, Cr, Cu, Mn, Zn, Fe) in sediment samples collected at two lakes, Volvi and Koronia, located in N. Greece. Samples were taken in two seasons, and the average concentration of the elements was calculated. The accuracy evaluated by comparing total trace metal concentrations with the sum of the five individual fractions proved to be satisfactory. Based on the results determined at one sampling point in Koronia and two sampling points along the lake Volvi, it seems that the two lakes have not yet been polluted. There were no significant changes in the individual seasonal concentrations of elements in this monitoring period. Cd, Pb, Cu and Cr are associated with the oxidizable, carbonates and residual fractions. Zn and Fe are associated with residual and reducible fractions. The metals that we most easily extracted in the samples analysed in both lakes are Pb, Cr, Cd, Cu and also Mn in the case of Koronia lake.     

Heavy metal contamination of brown seaweed and sediments from the UK coastline between the Wear river and the Tees river

The concentration of Fe, Mn, Zn, Cu, Pb, Ni, Cr, Cd, and Ag were determined in the brown alga Fucus vesiculosus and intertidal surface sediments from coastal locations of northeast England. Levels of heavy metals similar to those of polluted areas of the British coastline were detected. There is evidence of contamination (especially with Zn and Pb) in sediments from sites affected by colliery spoil and from the Wear estuary. The pelitic fraction ( < 63 microm) is usually more enriched in heavy metals, but it represents a very small percentage of the bulk samples. The fine-grained sand is a very important repository of contaminants especially where particles of colliery spoil, secondary mineral, and amorphous phases are present. Aqua regia-extracted Zn, Cu, and Pb in sediments are significantly correlated with those in seaweed. Despite the closure of all base metal and coal mines, and the cessation of many industrial activities in the region, sediments and brown algae are contaminated with heavy metals. The control site (Holy Island) and the Tees estuary appear to be the least affected.     

丹江口水库典型库湾及支流沉积物重金属污染分析及生态风险评价

对丹江口水库上游汉江支流及库湾沉积物中6种重金属元素的污染特征进行分析,采用效应阈值标准(NYSDEC)和Lars Hkanson潜在生态风险指数评价重金属的污染程度和环境风险。研究表明,库湾沉积物与支流沉积物中Ni、Pb含量较为接近;库湾沉积物中Cd、Cr、Cu、Zn含量分别高达186、2712、9991、4783 mg/kg,均超过支流沉积物中相应重金属含量2倍以上。各采样点表层（0~10 cm）沉积物中Pb含量均低于LEL值（最低效应阈值）,Cd、Ni含量均介于LEL值和SEL值（最高效应阈值）之间,而Cr、Cu、Zn含量均有超过SEL值的现象发生。考察沉积物重金属的富集程度发现各采样点表层沉积物中Ni和Pb均未发生富集,而Cd、Cr、Cu和Zn均存在不同程度的富集,其平均富集系数分别为712、180、163和284。根据重金属含量的相关性可知Ni和Pb主要来自于天然地球化学来源,而Cd、Cr、Cu和Zn则主要受人为源影响。以丹江口库区土壤（黄棕壤）中重金属背景值为参比,发现表层沉积物总体处于高生态风险,且以Cd生态风险为主;参与评价的5种重金属潜在生态风险程度顺序为Cd＞Cu＞Cr＞Zn＞Pb     

Biologically available trace metals in Mytilus edulis from the coast of Northeast England

The concentrations of Fe, Mn, Zn, Cr, Cu, Pb, Ni, Cd, and Ag were determined in soft tissue and shell material of mussel Mytilus edulis collected in the winter season from five coastal sites in the northeast of England. The trace metal levels observed were significantly high, particularly at locations affected by past coal mining activities (Blackhall) and present industrial sources (Middleton). The mussels from the chosen control site (Holy Island), a shellfish-designated area, were particularly enriched in Cu and Ag. The metal pollution index for the Bran Sands site, a heavily industrialised area on the Tees Estuary, was relatively low. At four sites out of five, the levels of Fe and Cu were negatively correlated with mussel size. No significant correlation with size was found for the other metals. With few exceptions, the elements Fe, Zn, and Mn accumulated preferentially in the soft tissue, whereas Pb, Cd, Cr, Ag, and Ni were more abundant in the hard part of the mussels. The Ag values in shell material were remarkably similar (about 6 mg kg⁻¹ – 7 mg kg⁻¹, dry wt) at all sites studied. In general, the data show that the mussels from the coastline studied accumulate metal concentrations comparable to or higher than the most contaminated sites reported in the literature.     

玄武湖沉积物中重金属的垂直分布

选取中国典型城市内湖--南京玄武湖为研究对象,采用目前运用较为广泛的欧洲标准测试分析委员会(now the Standards,Measurements and Testing Programme)推荐的BCR连续提取法对沉积物中Pb、Cd、Ni、Zn、Cr和Mo 6种重金属形态在垂向上的分布进行测定,并对其潜在迁移风险进行讨论。结果表明：玄武湖沉积物中6种重金属总量由大到小的顺序为：Zn＞Cr＞Mo＞Ni＞Pb＞Cd,含量分别为14880~24412、11255~13578、5519~7730、4142~4981、857~2005和129~173 mg/kg,除Pb外均高于南京土壤环境背景值。在50 cm的柱状沉积物样品中,Pb与Cd主要以可氧化态和残渣态存在,Mo、Ni、Zn和Cr主要以残渣态为主要的存在形态。6种重金属的总量与不同形态在垂向上的分布因金属种类不同有所差异。玄武湖沉积物中含有丰富的有机质(80%~110%),且pH值为偏酸性至近中性(582~713),沉积物中的重金属具有较高的潜在迁移风险,在城市湖泊污染治理中应予以足够的重视     

Characterisation of heavy metal discharge into the Ria of Huelva

The Ria of Huelva estuary, in SW Spain, is known to be one of the most heavy metal contaminated estuaries in the world. River contribution to the estuary of dissolved Cu, Zn, Mn, Cr, Ni, Cd, and As were analysed for the period 1988-2001. The obtained mean values show that this contribution, both because of the magnitude of total metals (895.1 kg/h), composition, toxicity (8.7 kg/h of As+Cd+Pb) and persistence, is an incomparable case in heavy metal contamination of estuaries. The amount and typology of heavy metal discharge to the Ria of Huelva are related to freshwater flow (and, consequently, to rainfall); as a result, two different types of heavy metal discharge can be distinguished in the estuary: during low water (50% of the days), with only 19.3 kg/h of heavy metals, and during high water or flood (17% of the days), where daily maximum discharge of 72,475 kg of heavy metals were recorded, from which 1481 kg were of As, 470 kg of Pb, and 170 kg of Cd. In the most frequent situation (77% of the days), the Odiel River discharges from 90% to 100% of the freshwater received by the estuary. Despite this, the high concentration of heavy metals in the Tinto River water causes this river to discharge into the Ria of Huelva 12.5% of fluvial total dissolved metal load received by the estuary.     

Acid mine drainage pollution in the Tinto and Odiel rivers (Iberian Pyrite Belt, SW Spain) and bioavailability of the transported metals to the Huelva Estuary

The Tinto and Odiel rivers are seriously affected by acid mine drainage (AMD) from the long-term mining activities in Iberian Pyrite Belt (IPB). As a consequence, the Huelva estuary is heavily contaminated by metals and metalloids. This study presents an estimation of the seasonal variation, and the dissolved contaminant load transported by both rivers from February 2002 to September 2004. Besides, toxicity and bioaccumulation tests with the sediments of the estuary have been conducted in order to measure the mobility of the toxic metals. Results show that the Tinto and Odiel rivers transport enormous quantities of dissolved metals to the estuary: 7900 t yr(-1) of Iron (Fe), 5800 t yr(-1) Aluminium (Al), 3500 t yr(-1) Zinc (Zn), 1700 t yr(-1) Copper (Cu), 1600 t yr(-1) Manganese (Mn) and minor quantities of other metals and metalloids. These values represent 37% of the global gross flux of dissolved Zn transported by rivers in to the ocean, and 15% of the global gross flux of dissolved Cu. These metals and metalloids usually sink in the estuarine sediments due to pH and salinity changes. The increase of salinity in the estuary favours the adsorption and trapping of metals. For this reason, the mobility and bioavailability of metals such as Zn, Cd and Cu is higher in sediments located in the area of fresh water influence that in sediments located in the marine influenced area of the estuary, showing a higher percentage of fractionation and bioaccumulation of these metals in the station influenced by the fresh water environment.     

Trace elements in fish from the Savannah river near Savannah river nuclear plant

A survey of trace element residues in fish from the Savannah River near Savannah River Nuclear Plant was undertaken in 1982. Fish muscle tissue was incubated by the wet digestion method. Fifteen trace elements were determined by flame atomic absorption spectrophotometry analysi of the digests. It was found that As, Se, Mg, Hg, Ca, Zn, and Fe levels were relatively higher than Pb, Cd, Ni, Co, Cr, and Mn in all fish species. In addition, in all fish species it seems that Pb, Cd, Ni, Co, Cr, and Mn levels were relatively higher than Cs and Cu. Cs and Cu levels were negligible in all fish species analyzed. Trace element levels found in these fish species were not high enough to render them dangerous for human consumption.     

天沙河沉积物中重金属污染特征与生态风险评价

采集天沙河表层沉积物,检测其中Cr、Ni、Cu、Zn、Cd和Pb 6种重金属的含量,分别采用内梅罗指数法(NI)、地累积指数法、Hakanson生态风险指数法和淡水生态系统沉积物基准法(SQGs)对沉积物中重金属污染的特征和生态风险进行评价,并对几种评价方法进行比较。结果表明：鉴于各采样点重金属的污染特征,采用内梅罗指数法和Hakanson生态风险指数法所得结果一致,杜阮河段、白沙河段及天沙河上游污染较严重,天沙河中下游污染程度相对较低;就各重金属的污染特征而言,采用地累积指数法和Hakanson生态风险指数法所得结果基本一致,Cd和Cu污染较严重,其次是Zn、Ni、Pb、Cr;而采用SQGs法的风险评价与其它方法所得结果存在一定差异,其主要原因是SQGs法基于污染物的生物毒性效应,而其他方法多反映单一重金属污染效应或多种重金属综合污染效应     

应用平衡分配法建立长江水系沉积物金属相对质量基准

在不同的条件下,沉积物可成为环境中污染物的“源”或“汇”,而受污染的沉积物会对水生生物带来危害。因此,需要制定沉积物质量基准(SQC),以此作为评价沉积物污染及其生态效应的基础。在过去的几年中,对利用平衡分配法来建立SQC的方法进行了广泛的研究,并被认为是最有效的方法之一。采用平衡分配法,初步建立了长江水系8种重金属及类金属(Cu, Zn, Cd, Pb, Ni, Fe, Hg,As)的沉积物相对质量基准。结果表明,上述重金属及类金属的SQC在从长江上游到下游,总体趋势上呈降低的分布特征,并由于地域环境条件的不同,存在着高SQC值单元及低SQC值单元。得出的SQC与国内已有的SQC具有可比性,但高于美国国家环保局提出的SQC,主要是由于采用平衡分配法建立的SQC是一种数值型的基准值,缺乏生物效应的校正。因此,在将其应用到沉积物污染状况评价之前,还需要进行深入的研究工作,特别是毒理学试验。     

经济发达县域耕地土壤重金属污染评价及其影响因素分析——以江苏省昆山市为例

通过对昆山市14个区镇91个土壤样品中As、Cd、Cr、Cu、Pb、Ni、Hg、Zn 8种重金属测定分析,对该市耕地土壤重金属污染进行评价并进行重金属污染的影响因素分析.结果表明,昆山市耕地土壤存在不同程度的轻微污染,重金属Cd、Cr、Cu、Pb、Hg、Zn均超过国家土壤背景值,旱地、水田中均以Hg污染范围较广、变异系数较大.综合污染指数表现为水田(1.15)＞旱地(1.00).区镇耕地重金属污染评价表明千灯、陆扬、石浦、锦溪、石牌处于警戒值之内,蓬朗、周庄、张浦、正仪、周市、巴城、淀山湖、花桥、陆家轻度污染;昆山市耕地土壤中重金属元素均未超过土壤环境基本容量,能够保证作物品质和农业持续发展.同时,研究表明区域重金属轻微污染具有复合污染的特性,Cd、Pb相关性最高(P=0.621 0), Pb与Hg、Cu、Zn、Cu与Cr也有相关性(0.438 7、0.426 0、0.350 9、0.394 0),区域重金属的轻微污染受人为因素影响显著,研究指出应加强对区域优先控制污染物Hg、次优先控制污染物Pb、Cd、Zn、Cu、Cr的控制与治理.     

南昌市街道灰尘重金属时空分布特征及健康风险评估

分析了南昌市夏季和冬季街道104个灰尘样品中的V、Cr、Co、Ni、Cu、Zn、As、Cd和Pb含量,并利用地积累指数（Igeo）计算其污染程度,并参考美国国家环保局(US EPA)推荐的健康风险模型评价灰尘重金属暴露的人体致癌和非致癌风险,通过主成分和相关分析识别南昌市灰尘重金属的可能来源。结果表明：南昌市街道灰尘中重金属Cr、Ni、Cu、Zn、Cd和Pb含量均显著高于江西省土壤背景值,而V、Co和As含量与江西省土壤背景值含量相近。重金属V、Co和As含量无显著季节差异,但冬夏季节含量的空间异质性较高,而Cu在季节和空间分布上均表现出显著的季节差异,其它重金属的高值区均分布在南昌市中心及老工业园附近;Igeo结果表明Cd、Cu、Zn和Cr的污染程度相对较高,而V、As和Co污染程度较轻;重金属3种暴露途径的风险排序为手-口暴露>皮肤接触暴露>呼吸暴露,其中儿童会遭受更大的非致癌风险。除了灰尘As和Cr对儿童的暴露在局部区域HQ和HI值大于1,其它重金属对不同人群的HQ和HI值均小于1。总体而言,南昌市灰尘重金属的致癌风险CR均在安全阈值范围内,大小排序为Cr > As > Co > Ni > Cd。南昌市灰尘重金属的来源广泛,其中As、Co和V主要来源于岩石风化,其它重金属元素主要来源于交通和工业等人类活动。 关键词： 街道灰尘;重金属;时空分布;健康风险;南昌市     

鄱阳湖主要入湖口重金属的分布及潜在风险评价

于2011年5月在鄱阳湖的主要入湖口采集了水样和表层沉积物,测定并分析了其中Cu、Zn、Pb、Cd 4种重金属元素的含量和分布。同时采用地积累指数法、潜在生态危害指数法和生态毒性效应等评价方法对沉积物中重金属的污染状况进行了分析评价。结果显示：鄱阳湖主要入湖口水体重金属Cu、Zn、Pb、Cd含量均符合国家渔业水质标准要求,除修河的Pb和信江、饶河入湖口的Cd含量属于国家地表水Ⅱ类水质外,其它所有样地的4种重金属含量均低于国家地表水I类标准限值。沉积物中4种重金属含量均超过鄱阳湖相应背景值且呈积累富集的趋势,其中信江入湖口、饶河入湖口以及三江口已受到重金属的严重污染,潜在生态危害均为中等,而污染最轻的区域为南主湖区。揭示重金属污染程度顺序为Cu＞Zn＞Pb＞Cd;单个重金属潜在生态风险顺序为Cd＞Cu＞Pb＞Zn。进一步的生态毒性效应评价结果表明,虽然鄱阳湖主要入湖口沉积物已经受到重金属污染,但对多数底栖生物未产生明显毒害     

长三角典型城郊农田土壤-浙贝母重金属迁移特征研究

城郊生态系统中土壤重金属分布及其在土壤—植物系统的迁移和富集特征是城乡共生体土壤安全研究的热点问题。以典型经济作物浙贝母(Fritillaria thunbergii)为例,基于野外采样和实验分析,对长三角代表性城郊农田中土壤—植物系统重金属的分布、富集和迁移特征开展研究。结果表明:受人类活动的影响,城郊农田土壤中重金属除Cr外,Cu、Zn、As、Cd和Pb的平均含量超过土壤背景值,并且不同重金属在空间分布上表现较高的空间异质性。除Cd和Cr外,浙贝母植株不同部位重金属含量表现为叶、茎显著高于鳞茎,叶中重金属含量可达到鳞茎的5～10倍,表明叶比鳞茎更易富集重金属。重金属迁移系数分析表明,Cr、Cu、Zn、As、Cd和Pb主要富集在浙贝母植株的地上部分,且不同重金属在植株中的迁移和富集能力具有较大的差异。浙贝母地上部分对Cr、As和Pb的富集能力较低,对Cu、Zn和Cd的富集能力相对较强。相比而言,鳞茎对不同重金属的富集能力均较弱,综合污染评价也表明,浙贝母鳞茎中重金属含量并未超过污染标准。