Distribution and their pollution assessment of heavy metals in the sediments of the Yalu River Estuary and its adjacent coastal waters

The present paper deals with the distribution patterns of heavy metals and the associated influenc- ing factors in the Yalu River Estuary and its adjacent coastal waters. Based upon the analysis of the surficial and core sediments measurements, the pollution of heavy metal and potentiM ecological risk were evaluated. The burial flux and contents of heavy metals （except for copper） have been continuously increasing since the 1920s. Therefore, the gross potential ecological risk for the sedi- ments was high or very high, and the study area was endangered by heavy metals contamination. Heavy metals originated mainly from upstream pollutant input, correlation analysis showed that chromium, nickel, zinc~ cadmium, lead, arsenic, and mercury in the sediments of the middle and west channels as well as the sea area of the western Yalu River Estuary concentrations were most probably derived from similar sources. In contrast, the metal of copper most probably originated from sources different from the other metals. Preliminary studies indicate that copper contamina- tion was most likely the result of emission from mining activities situated at the upstream of the river. The contents of heavy metals in the sediments of estuarine turbidity maximum zone of Yalu River were larger than those of any other areas in the middle channel. With large portion of fine sediments, weaker hydrodynamics, and richer sources of heavy metals, the sediments of the west channel, were even more enriched with heavy metals than those of the middle channel.

Developing sediment quality criteria for heavy metal pollution in the Le An River with equilibrium partitioning approach

Equilibrium partitioning(EqP) approach was selected to establish the sediment quality criteria(SQC) in the Le An River near Dexing Copper Mine. Both freshwater quality criteria (WQC) for some heavy metals regulated by USEPA and national quality standards of surface water recommended by CNEPA were used as protective levels of aquatic organisms in this study. Meanwhile, the partitioning coefficients were derived directly from measured data. Comparison between SQC in this region and concentrations of contaminants in situ clearly indicated the distribution characteristics of metal contamination along the river. And the results also illustrated that measures of some metals exceeded their SQC levels in different degree, especially Cu.

Sediment quality criteria for heavy metal pollution in the Le An River with triad approach

In this study, integrative traid was used to sediment quality in the Le An River, which has been strongly contaminated by large amount of Cu, Pb, Zn,Cd, As and Cr discharging from mining activities. All available data collected from chemical analyses,toxic tests and field survey on benthic macroinvertebrates were transformed into ratio to reference(RTR) and relevant scales.The responses of receiving environment to mining impacts were illustrated by traid graphs. Traid results indicated that a sectional distribution pattern existed from upstream to downstream:(a) relative clean upstream;(b) serious contaminated middle stream;(c) gradual recovery downstream. This situation was closely related with local mining activities, which caused obvious degradation of sediment quality in some sections, therefore, remediation was required urgently.

Assessment of Heavy Metals Pollution in the Sediments of Euphrates River, Iraq

Fourteen bed sediments samples were collected from the Euphrates River in order to determine concentrations, seasonal, spatial and contamination assessment of heavy metals such as Pb, Cd, Zn, Cu, Ni, Co, Fe, Mn and Cr. The mean concentrations are as follows: 2249.47 mg/kg for Fe, 228.18 mg/kg for Mn, 67.08 mg/kg for Ni, 58.4 mg/kg for Cr, 48.00 mg/kg for Zn, 28.16 mg/kg for Co, 22.56 mg/kg for Pb, 18.91 mg/kg for Cu and 1.87 mg/kg for Cd. To assess metal contamination in sediments, sediment quality guidelines were applied. The mean concentration of Cd, Cu, Ni, Fe, Mn, and Cr exceeded the USEPA guideline. The metal contamination in the sediments was also evaluated by appling enrichment factor (EF), contamination factor (CF), geo-accumulation index (Igeo) and pollution load index (PLI). Based on enrichment factor (EF), the Euphrates River sediments have very high enrichment for Pb, extremely high for Cd, moderate for Zn, significant to very high for Ni, very high to extremely high for Co, moderate to significant for Mn and significant to very high for Cr. According to contamination factor (CF), Cd and Cr are responsible for very high contamination. According to Igeo, the Euphrates River sediments are moderately to strongly polluted by Cd. Based on PLI, all sampling sites suggest no overall pollution of site quality.

Application of Pollution Indices in the Assessment of Heavy Metal Contamination of Surface Sediments of River Bonsa, Ghana

Heavy metal contamination of sediments is a major risk to ecological systems and human health. Not only do sediments influence the quality of the water column, but can be transferred to micro biota and fishes, ultimately ending up at higher trophic levels in the food chain though biomagnification. This study was carried out to assess the contamination levels of heavy metals in the sediments of river Bonsa. Ten sediment samples were taken along the river and analyzed for Copper (Cu), Lead (Pb), Manganese (Mn), Iron (Fe), Zinc (Zn), Cadmium (Cd), Chromium (Cr), Cobalt (Co), and Nickel (Ni) using Atomic Absorption Spectroscopy (AAS). Data analysis was accomplished by comparing the measured heavy metal concentrations to Australian and New Zealand Environment and Conservation Council (ANZECC) and National Oceanic and Atmospheric Administration (NOAA) fresh water sediment quality guidelines and by the computation of geo-accumulation indices and enrichment factors. The results show that apart from Ni which had two of its sample concentrations (at BS1 21.167 mg/kg and at BS2 29.374 mg/kg) exceeding the ANZECC lower limit (21 mg/kg) guideline for fresh water sediment, all other heavy metals recorded concentrations below the lower limits of their respective ANZECC standards. Out of the 10 samples analyzed, 7 recorded Mn concentrations above the NOAA ARC TEL. A one-sample t-test also showed that the mean concentrations of Cu, Pb, Cd, Zn, Ni, and Cr were significantly lower than their respective ANZECC threshold values and Fe concentration was also significantly lower than the NOAA threshold;however, there was no significant difference between Mn mean value and the corresponding NOAA guideline value. The assessment of heavy metal pollution was derived using the Enrichment Factor (EF) and geo-accumulation indices (I-geo). The computed enrichment factors indicated that all the heavy metals except Ni are from natural sources (i.e., EF < 1.5) signifying a degree of heavy metal depletion rather than enrichment. The sources of Ni were attributed to domestic waste disposal into the river at sampling points BS1 and BS2 as well as run offs from a nearby auto mechanic workshop. All the metals had I-geo values between 0 and 1 (0 < I-geo < 1) denoting unpolluted to moderately polluted sediments. Thus, in terms of heavy metals, the river is unpolluted. These findings are very important as it shows that river Bonsa has not yet been impacted as far as heavy metals are concerned and the data gathered may serve as baseline for future studies.

THE RESEARCH ON THE DISTRIBUTION AND FORMS OF HEAVY METALS IN THE XIANGJIANG RIVER SEDIMENTS

In this paper, the contents and various forms of Cd, Cu, Zn and Pb in the sediments of the Xiangjiang River have been investigated. The presentation of this paper focuses on the various forms and characteristics of the heavy metals in the column sediments at Xiawan Port of Zhuzhou, which has been severely polluted by a metallurgical plant.The forms of the heavy metals discussed in this paper are: The concentration of the exchangeable forms of Cd, Cu, Zn and Pb, in the forms of carbonates and Fe/ Mn oxide in water, the combination of Cu with organic matter and form, and the proportion of the residue form at each section have been studied.

Water Quality and Heavy Metal Monitoring in Water, Sediments, and Tissues of the African Catfish Clarias gariepinus (Burchell, 1822) from the River Nile, Egypt

Water quality of the river Nile and trace elements of the water, sediments and fish tissues were investigated in the current work. Eighteen different sampling points were selected along the whole course of the River Nile from its spring at Aswan to its estuaries at Rosetta and Damietta. Higher mean value of conductivity, alkalinity, chemical oxygen demand (COD), total organic carbon (TOC), ammonia (NH3), nitrate (NO3), total solid (TS), sulphate (SO4), chloride (Cl), orthophosphate were recorded in the water of Damietta and Rosetta branches comparing to other sites. Also trace metals in the water, sediments and tissues of Clarias gariepinus increased significantly (P Fe > Cu > Pb > Mn > Cr> Cd > Hg. In the gill tissues theses metals were accumulated in the following order Fe > Zn > Mn > Pb > Cr > Cu > Cd> Hg. The low accumulation of metals in muscle may be due to lack of binding affinity of these metals with the proteins of muscle. This is particularly important because muscles contribute the greatest mass of the flesh that is consumed as food.

Assessment of heavy metals in sediment in a heavily polluted urban river in the Chaohu Basin, China

The Nanfei River （Anhui Province, China） is a severely polluted urban river that flows into Chaohu Lake. In the present study, sediments were collected from the river and analyzed for their heavy metal contents. Multivariate statistics and the fuzzy comprehensive assessment method were used to determine the sources of pollution, the current pollution status, and spatial and temporal variations in heavy metal pollution in sediments. The concentrations of arsenic （As）, cadmium （Cd）, chromium （Cr）, copper （Cu）, mercury （Hg）, nickel （Ni）, lead （Pb）, and zinc （Zn） in sediments ranged from 5.67-113, 0.08-40.2, 41.6-524, 15.5-460, 0.03-4.84, 13.5-180, 18.8-250, and 47.9-1 996 mg/kg, and the average concentrations of each metal were 1.7, 38.7, 1.8, 5.5, l 8.8, 1.3, 2.5, and 11.1 times greater than the background values, respectively. Multivariate statistical analysis demonstrated that Hg, Cu, Cr, Cd, and Ni may have originated from industrial activities, whereas As and Pb came from agricultural activities. The fuzzy comprehensive assessment method, based on the fuzzy mathematics theory, was used to obtain a detailed assessment of the sediment quality in the Nanfei River watershed. The results indicated that the pollution was moderate in the downstream tributaries of the Nianbu and Dianbu Rivers, but was severe in the main channel of the Nanfei River and in the upstream tributaries of the Sill and Banqiao Rivers. Therefore, sediments in the Nanfei River watershed are heavily polluted and urgent measures should be taken to remedy the status.

Geochemical Characteristics of Heavy Metals in Riparian Sediment Pore Water of Songhua River, Northeast China

This study reports the geochemical characteristics of zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), mercury (Hg), iron (Fe), and manganese (Mn) in the riparian sediment pore water of the Songhua River, Northeast China. In total, 36 pore water samples and 18 surface water samples from three typical sections were collected and analyzed in June 2009. Cluster analysis of heavy metals was performed to analyze the pollution sources of the metals. Results showed that Hg concentrations in the pore water were greater than those in the surface water, indicating a potential ability of Hg release from riparian sediment system to river water. However, concentrations of Fe and Mn in the surface water were greater than those in the pore water, demonstrating that the microenvironments of riparian and riverbed sediment systems were quite different. Variations of Zn, Cu, Pb and Ni between the surface and the pore water were different in each section. Most metals had similar horizontal and profile distribution characteristics in the three sections except for Zn and Ni. Hg, Fe and Mn concentrations in the pore water increased gradually with the increase in horizontal distance from water body, in contrast to this, Cu decreased, and Pb presented a fluctuating trend. With the increase in depth, Pb and Fe, Cu and Mn showed the same trends, and Hg showed a variable trend. The above distribution characteristics could mainly be attributed to the properties and the interactions of metals, pH and oxidation-reduction conditions, and the complex pollution sources and hydrologic regime in history. The probable sources of metals include the historical and ongoing discharge of industrial wastewater, mining activities, sewage irrigation for agricultural production, and atmospheric deposition from coal-fired plants.

Assessment of heavy metals in sediment cores from Xiangjiang River,Chang-Zhu-Tan region,Hunan Province,China

Samples were collected from two core sediments(C1 and C2) of Xiangjiang River,Chang-Zhu-Tan region,Hunan Province,China.The heavy metal contents are relatively higher,especially for the surface or near the surface layers.The calculated anthropogenic factor values indicate that all the heavy metals except for Cr in the core samples are enriched,especially for Cd,with the maximum enriching coefficients of 119.44,and 84.67 in C1 and C2,respectively.The correlation of heavy metals with sulphur indicates that they are precipitated as metal sulphides.Correlation matrix shows significant association between heavy metals and mud.Factor analysis identifies that signified anthropogenic activities affect the region of Xiangjiang River.

Water Quality and Some Heavy Metals in Water and Sediments of Euphrates River, Iraq

Water samples, sediments from three stations in Euphrates River, lraq were analyzed quantitatively for some physical and chemical characters and six heavy metals （Co, Cu, Fe, Mn, Ni and Pb） using flam atomic absorption spectrophotpmeter in period Sept. 2009-Oct. 2010. The physical and chemical characters included temperature, pH, water flow, salinity, dissolved oxygen, BOD5, alkalinity total hardness, calcium and nutrients （nitrite, nitrate reactive phosphate and silicate）. The results showed variation in water flow 0.05-0.40 m/sec., according to the values of salinity 0.40%-0.60% values of the BOD5 were ranged between 0.2-4.3 mg/L. The mean concentration of the heavy metals （Pb, Ni, Mn, Co, Cu and Fe） of the dissolved phase in water were 0.13 μg/L, 0.021 μg/L, 0.31 μg/L, 4.29 μg/L, 7.78 μg/L, 6.46 μg/L and 79.04 μg/L, respectively, while their concentration in the particulate phase were 0.59 μg/g, 0.06 μg/g, 0.42 μg/g, 50.06 μg/g, 6.61 μg/g, 7.17 vg/g and 149.42 μg/g dry weight, respectively. Also the mean concentrations of heavy metals in sediment （exchangeable phase） were 0.51 vg/g,0.18 vg/g, 0.08 μg/g, 61.39 μg/g, 5.40 μg/g, 14.06 vg/g and 130.05 μg/g dry weight respectively, and 0.40 μg/g, 0.17 μg/g, 0.10 μg/g, 63.01 μg/g, 4.64 μg/g, 18.44 μg/g and 126.26 μg/g D.W. respectively in residual phase of sediment.

Assessment of Heavy Metal Contaminants Using Pollution Indices in Ankobra River at Prestea Huni-Valley District, Ghana

The reliance of communities on River Ankobra as the source of drinking water makes the assessment of its quality very imperative to human health and environmental management. The objective of this work was to investigate the concentration of heavy metal in the Ankobra River sediments at the Prestea Huni-Valley District using pollution indices. Sediments were collected randomly from the bottom of the Ankobra River at four different communities namely: Awodua, Heman, Ankobra and Tarkwa Breman. The presence of a set of heavy metals Fe, Mn, Cd, Pb, Zn, Cu, and Hg in the sediments was determined using Atomic Absorption Spectroscopy (AAS). The results showed that the concentration of Fe, As, and Hg did not differ significantly (p > 0.05) amongst the four communities but significant variation in the levels of Cu, Mn, Cd, Pb, and Zn was found (p < 0.05) amongst the sampling areas. The geo-accumulation index revealed that the communities were not polluted with Cu, Mn, Fe, Pb and Zn. However, all communities except Tarkwa Breman were found to have exceptionally high levels of Cd. The contamination factor results were consistent with the I-geo results. The pollution load index (PLI) showed that the four communities were not polluted with heavy metals. Strong statistical positive relationship were found between Mn and Cu;Cd and Cu;Pb and Mn;Hg and Mn;Zn and Cu;Zn and Mn;Zn and Pb;Zn and Hg whilst As and Fe showed strong negative correlation.

Distribution of Heavy Metals and Rare Earth Elements in the Surface Sediments of Penang River Estuary, Malaysia

Geochemical sediment of the tropical Pinang River, Malaysia was carried out with the aim at documenting elemental concentrations and pollution level assessment. Concentration of selected heavy metals (Cu, Cd, Cr, Pb, Zn and Mn), rare earth elements, TOC and grain size distribution of sediments were determined at 100 m sampling interval along the river. Sediment size showed a positive correlation with ∑REE and Mn and medium correlations with TOC, Zn, Cu, Cr and Pb contents showing enrichment in the clay size fraction. Results of enrichment factor and geoaccumulation index showed that most of the elemental sources were natural (especially REE) and mostly likely represented background values. However, pollution load index revealed the higher levels of Cr, Cd, Zn and Pb, and, therefore, indicating to the anthropogenic sources (i.e. fishing activities) especially in the downstream locations. Thus, the Pinang River is classified as moderately to highly polluted.

A Pilot Study on the Concentration of Heavy Metals in Sediments from the Lower Orange River, //Karas Region, Namibia

Global water shortage is caused not just by the physical scarcity of water, but also by gradual deterioration of the quality of water resources such as lakes, streams and rivers with heavy metals. This present study evaluated the status of Mn, Fe, Cr, Cu, Ni, As, Zn, Pb and Cd in sediments from the lower Orange River by Inductively Coupled Plasma Atomic Emission Spectrometry technique by collecting a total of eleven samples, each weighing 1 - 2 kg at the depth of 15 - 20 cm from two observations sites along the lower Orange River and applying pollution indicators such as contamination factor(CF), pollution load index(PLI), index of geo-accumulation(Igeo) and enrichment factor(EF) to assay the nature and extent of heavy metals contamination in sediments. The sequence of the total heavy metal content in descending order was Fe > Mn > Cr > As > Zn > Ni > Cu > Pb > Cd. The results of CF and Igeo showed Mn, Cd, Ni, Zn and Pb were minor sources of sediment contamination since most of the samples were unpolluted and moderately polluted by these metals. However, most sediments were moderate to considerably polluted with Cr, As and Fe suggesting that these were the major pollution sources. The value of PLI at one of the two observation sites was equivalent to the value of baseline level, while the next site indicted quality deterioration of the sediments. The EF revealed that Cr was moderately enriched and arsenic (As) significantly enriched in all the sediments, which suggested contamination due to anthropogenic intervention. Hence, it is recommended that sediment quality be evaluated on a regular basis to avoid further deterioration of the Orange River’s health, which might have detrimental repercussions for both aquatic life and local communities along the river.

A 50-year sedimentary record of heavy metals and their chemical speciations in the Shuangtaizi River estuary(China):implications for pollution and biodegradation

Two parallel sediment cores collected from tidal flat located in the Shuangtaizi River estuary were analyzed for heavy metal concentrations and chemical speciations.Based on the ^(137)Cs activity profile,mean sedimentation rate at the sampling site during the past 50 years was estimated to be 1.3 cm·a^(-1).Correlation analyses show that almost all the metals are associated with each other,suggesting that these metals might be derived from same sources and/or affected by same geochemical processes.Influence of total organic carbon(TOC)content on the concentrations of Cr,Ni,Cu and Cd is evident.Silt and clay contents,instead of sand content,play an important role in the distribution of these metals.The dominant binding phases for most of the metals(except for Cd)are the residual.The relative decrease of the residual fraction of Cd and Pb in the upper 66 cm of the core is striking.The distribution of chemical fraction confirms that the residual fractions of these metals have a natural origin,while only the non-residual fractions of Cd and Pb increased upward the core due to pollution in the past five decades.Pollution assessment on these heavy metals based on Index of Geoaccumulation(I_(geo))also demonstrates that most of the metals are unpolluted.The weak pollution as observed in the sediments is perhaps related to a local plant,the Suaeda heteroptera Kitag,which may have played a significant role in the biodegradation of these metals and the metal distribution in the estuary.

Effects of in situ biological treatments on heavy metal release of urban river sediment

A typical fiver in Yangzhou City was used to study the effects of artificial aeration, eco-brick cover, biological packing cover, and low-sited plant floating beds on the release of heavy metals from urban river sediments. This work showed that 1） the Cr release rate was decreased by 50.3%-89.6%, with an average of 59.3%, thereby reducing the Cr pollution load to the overlying water by 36.6%-82.7%, with an average of 53.3%; 2） the Zn release rate was reduced by 21.0%-88.9%, with an average of 42.3%, and the Zn pollution load of the overlying water was reduced by 38.0%-67.1%, with an average of 55.0%; 3） the Cu release rate was reduced by 27.5%-91.0%, with an average of 55.3%, and the Cu load of the overlying water was reduced by 57.1%-83.7%, with an average of 71.7%; 4） the Pb release rate was reduced by 11.8%- 79.3%, with an average of 41.2%, and the Pb pollution load of the overlying water was reduced by -1.3%-70.7%, with an average of 29.8%. We also found that the effects of in situ biological treatments on the release of heavy metals were affected by the extent of sediment disturbance. For integrated applications, high-disturbance treatments should be combined with low-disturbance treatments to reduce the explosive release of pollutants caused by sediment disturbance during the treatment operation to achieve better overall treatment effects.

大清河流域下游沉积物重金属污染优控源解析

为探讨重金属不同污染源对生态和人体健康风险影响,本文以大清河流域下游为研究对象,采集并测定36个沉积物样品重金属Cu、Pb、Ni和Cr的含量,采用传统分析法量化重金属污染程度,利用正定矩阵因子分析法(PMF)对沉积物重金属污染来源进行分析.同时,在PMF源解析的基础上,结合重金属毒性和环境背景值等因素,运用PMF与潜在生态风险指数模型(ERI)、人体健康风险评估模型(HHRA)相结合的方法定量解析污染源对生态环境风险和人体健康风险的贡献率.单因子污染指数结果表明,以河北省土壤重金属本底值为标准值,研究区4种重金属Pb、Ni、Cu和Cr均为轻微污染.PMF解析表明,重金属污染源有工业源(43.26%)>农业-交通源(34.97%)>交通-自然源(21.77%).污染源生态风险评估模型显示,交通-自然源(39.21%)>农业-交通源(34.07%)>工业源(26.72%),交通-自然源为潜在生态风险优控源;污染源健康风险评估模型显示,工业源(43.98%)>农业-交通源(26.90%)>交通-自然源(29.12%),工业源为人体健康风险优控源,且Cr为人体健康风险优控污染物.

付疃河中下游表层沉积物污染状况评价

为探明付疃河中下游沉积物污染情况,对河底12个采样点表层沉积物中的TN,TP,OM和重金属(Cr,Ni,Cu,Zn,As,Cd,Pb)的含量开展调查,分析其分布特征、来源、污染水平以及健康风险。结果表明,城区段河流以及日照水库出库处TN,TP及OM相对较高,且相应的污染指数均为重度污染,其他区域为轻度~中度污染;除Pb外,其余6种重金属含量均高于东港区土壤背景值;城区段河流以及日照水库出口处重金属含量相对较高,可能受工业、农业及交通等复合因素影响导致;Cd处于轻度污染状态或中等生态危害状态,各类重金属均不存在非致癌健康风险,但存在可接受的致癌风险。

巢湖北岸烔炀河流域池塘沉积物中重金属污染特征

在巢湖北岸烔炀河流域,选择不同利用类型的池塘钻取了沉积物柱状样,分析了沉积物重金属元素浓度,并剖析了重金属在水平、垂向上的分布特征和污染程度。结果表明,池塘表层沉积物中Cr、As、Hg、Cd、Cu、Pb、Ni、Zn浓度分别为56.5~91.0、6.4~10.1、0.06~0.11、0.10~0.25、18.07~28.77、11.58~17.60、15.94~19.0、42.26~68.07 mg/kg;垂向上随着沉积物深度增加,重金属浓度总体呈下降趋势。烔炀镇老镇区池塘(S1)表层沉积物中重金属浓度高于其他池塘。烔炀河流域池塘沉积物中重金属Cr、Hg、Cu、Zn、As等5种重金属元素具有同源性,受成土母质影响,而Ni、Pb、Cd 3种重金属受人类活动影响;池塘表层沉积物重金属综合潜在生态风险指数处于轻微生态风险。

资水下游某石煤矿区沉积物重金属污染评价和来源解析

以资水下游某石煤矿区为研究区域,分析该矿区河流沉积物中重金属的空间分布、污染程度和来源。研究共采集了28个表层沉积物样本,并对其中8种重金属的含量进行了测定,包括镉(Cd)、铬(Cr)、汞(Hg)、砷(As)、铅(Pb)、铜(Cu)、镍(Ni)和锌(Zn)。采用地累积指数和潜在生态风险指数进行重金属污染评价,运用主成分分析(PCA)、正定矩阵因子(PMF)等方法识别重金属污染来源。结果表明,除Cr外,Cd、Hg、As、Pb、Cu、Zn、Ni含量的中值均高于洞庭湖水系沉积物背景值。其中,Cd、As含量超标问题较为严重,超过《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618—2018)风险筛选值的样点比率分别为96.55%、58.62%。地累积指数和潜在生态风险指数分析表明,沉积物中Cd、Hg污染最为严重,Cr污染程度最低。沉积物重金属主要来源为石煤开采源、交通和农业混合源、自然源以及大气沉降源,贡献率分别为33.8%、20.4%、17.7%和28.1%。研究表明,研究区沉积物受到石煤开采影响,重金属Cd超标严重,应加强管控。