Concentrations of heavy metals and aquatic macrophytes of Govind Ballabh Pant Sagar an anthropogenic lake affected by coal mining effluent

Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia’s largest anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation. In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between different morphological tissues of the sampled plants reveled the metal concentration in following order roots > leaves. Analyses of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants for pollution monitoring of these metals.     

Evaluation of uptake rate of heavy metals by Eichhornia crassipes and Hydrilla verticillata

Lakes, ponds, and streams are the sources of surface water, which anchorage the survival of aquatic life flora and fauna and maintain ecological balance. Due to urbanization, population explosion, and industrialization, these natural sources are getting polluted. Present paper is an attempt to evaluate the uptake rate of heavy metals namely lead (Pb), zinc (Zn), iron (Fe), and chromium (Cr) by the macrophytes. The two macrophytes taken for the study are Eichhornia crassipes and Hydrilla verticillata. Both macrophytes have the capacity to absorb heavy metals from contaminated water. The present experimental study was conducted to compare and identify their potential to improve the water quality by removing the heavy metals. The paper critically evaluates the water-purifying capacity of submerged macrophyte (H. verticillata) and free-floating macrophyte (E. crassipes). It also evaluates the extent up to which heavy metal can be removed by macrophyte in a given period of time.     

Heavy metal biomonitoring and phytoremediation potentialities of aquatic macrophytes in River Nile

The concentrations of Cd, Cu, Pb, and Zn in sediments, water, and different plant organs of six aquatic vascular plant species, Ceratophyllum demersum L. Echinochloa pyramidalis (Lam.) Hitchc. & Chase; Eichhornia crassipes (Mart.) Solms-Laub; Myriophyllum spicatum L.; Phragmites australis (Cav.) Trin. ex Steud; and Typha domingensis (Pers.) Poir. ex Steud, growing naturally in the Nile system (Sohag Governorate), were investigated. The aim was to define which species and which plant organs exhibit the greatest accumulation and evaluate whether these species could be usefully employed in biomonitoring and phytoremediation programs. The recorded metals in water samples were above the standard levels of both US Environmental Protection Agency and Egyptian Environmental Affairs Agency except for Pb. The concentrations of heavy metals in water, sediments, and plants possess the same trend: Zn > Cu > Pb > Cd which reflects the biomonitoring potentialities of the investigated plant species. Generally, the variation of heavy element concentrations in water and sediments in relation to site and season, as assessed by two-way repeated measured ANOVA, was significant (p < 0.05). However, insignificant variations were observed in the concentrations of Pb and Cd in sediments in relation to season and of Cu and Zn in relation to site. Results also showed that the selectivity of the heavy elements for the investigated plants varied significantly (p < 0.05) with species variation. The accumulation capability of the investigated species could be arranged according to this pattern: C. demersum > E. crassipes > M. spicatum > E. pyramidalis > T. domingensis > P. australis. On the basis of the element concentrations, roots of all the studied species contain higher concentrations of Cu and Zn than shoots while leaves usually acquire the highest concentrations of Pb. Cd concentrations among different plant organs are comparable except in M. spicatum where the highest Cd concentrations were recorded in the leaves. Our results also demonstrated that all the studied species can accumulate more than 1,450-fold the concentration of the investigated heavy elements in water rendering them of interest for use in phytoremediation studies of polluted waters. Given the absence of systematic water quality monitoring, heavy elements in plants, rather than sediments, provide a cost-effective means for assessing heavy element accumulation in aquatic systems during plant organ lifespan.     

Fuzzy logic modeling of bioaccumulation pattern of metals in coastal biota of Ondo State,Nigeria

The accumulation patterns of ten metals in tissues of plant, Eichornia crassipes, and fishes, Hydrocynus forskahlii and Oreochromis mossambicus, were modeled with simple fuzzy classification (SFC) to assess toxic effects of anthropogenic activities on the coastal biota. The plant sample was separated into root, stem, and leaves and the fishes into bones, internal tissues, and muscles. They were analyzed for As, Cd, Cr, Cu, Ni, Pb, V, Fe, Mn, and Zn after wet oxidation of their dried samples. The results were converted into membership functions of five accumulation classes and aggregated with SFC. The classification results showed that there was no metal accumulation in the plant parts while the fishes were classified into low accumulation category. The internal tissues of the fishes had higher metal accumulation than the other parts. Generally, Fe and Mn had highest concentrations in the biota but are natural to the area and may not constitute significant risk. Cr had the highest transfer and accumulation from the coastal water into the aquatic lives and may be indicative of risk prone system being a toxic metal. Metal contaminations in the zone had not significantly accumulated in the biota making them less prone to risk associated with metal accumulation.     

Heavy Metal Uptake By Scirpus Littoralis Schrad. From Fly Ash Dosed and Metal Spiked Soils

Scirpus littoralis is a wetland plant commonly found in Yamuna flood plains of Delhi, India. The ability of Scirpus littoralis to take up and translocate five metals- Mn, Ni, Cu, Zn and Pb from fly ash dosed and metal spiked soils were studied under waterlogged and field conditions for 90 days. Scirpus littoralis accumulated Mn, Ni, Cu, Zn and Pb upto a maximum of 494.92, 56.37, 144.98, 207.95 and 93.08 ppm dry wt., respectively in below ground organs (BO) in 90 days time. The metal content ratios BO/soil (B/S) were higher than shoot/soil ratios (T/S) for all the metals, the highest being for Ni. Metal ratios BO/water (B/W) were also higher than shoot/water (T/W) ratios but the B/W ratio was maximum for Zn. The changes in nutrient status (N, P) in soil water and plants were also studied at interval of 30 days. The Pearson's correlation between metal uptake and N, P uptake were calculated. All the metals except Ni showed negative correlation with nitrogen but they were all non-significant. However, P uptake showed positive correlations with all the metals and all were significant at 1% confidence limit.     

Bioaccumulation of Metals in Fish of Salmonidae Family and the Impact on Fish Meat Quality

The study was aimed at determining the levels of metals in water samples and muscles of the fish caught in the Una River basin, located in the northwestern part of Bosnia and Herzegovina. For that purpose, three fish species: Brown Trout (Salmo trutta m. fario), Grayling (Thymallus thymallus) and Californian Trout (Salmo gairdneri), together with stem water samples, were analyzed for metal concentrations (Pb, Hg, Cd, As, Mn, Ni, Cu, Cr, Se, Co, Sn, Zn, Fe, Ca, P) during a 2-year period. The fish was captured using electric fishing, nets or fishing equipment. The capture was undertaken on three sites (the river source, the middle flow and the river mouth) of each of the five biggest rivers belonging to the Una River basin (Unac, Krušnica, Sana, Klokot, and Una). The concentrations of metals in each sample were determined via atomic absorption spectrophotometry. In the tested waters, the presence of Mn in concentrations higher than permitted (0.07 mg/l) had been detected. In the tested meat, the following average concentrations of metals (mg/kg) had been found: Pb (0.67), Cd (0.06), Mn (0.65), Ni (0.15), Cu (0.79), Cr (1.05), Se (0.03), Zn (8.92), Fe (5.40), Ca (14.68), and P (10.85). The correlation between Mn concentrations identified in the tested waters and those identified in the meat of Brown Trout was revealed to be statistically significant, which confirms that, over time, bioaccumulation of metals took place. Even though the results were not indicative of contamination, they strongly suggest that constant monitoring of the ecosystems in reference should be implemented.     

Assessment of the exposure of two fish species to metals pollution in the Ogun river catchments, Ketu, Lagos, Nigeria

The concentrations of metals (Ca, Cd, Fe, Mn, Pb and Zn) were determined by flame atomic absorption spectrophotometry in water, sediments and fish samples in the Ogun river catchments, Ketu, Lagos, which is an important bird nesting, fishing and drinking water source. The results show that the southern tip bothering the Lagos lagoon is where the highest metal concentrations are found in the fish species (Tilapia sp. and Chrysichthys sp.), whereas the Agboyi creek segment near the lagoon with higher surrounding human population density recorded higher levels of metals in sediments and water samples. The two fish species accumulated different amounts of metals. However, the differences were not statistically different at p < 0.05. There is a significant correlation (p < 0.05) for Cd concentration in water. The concentrations of Pb in sampling points 3 and 4 as well as Cd, Mn and Fe in all six sampling points exceeds the World Health Organization (WHO) limits for drinking water. Levels of metals obtained for sediments are within the range reported for Nigeria’s river sediments. Based on this study, the human risks for heavy metals in the harvested fish species from the Ogun river catchments, Ketu, are low for now as the concentrations were below the recommended Food and Agriculture Organization (FAO) maximum limits for Pb (0.5 mg/Kg), Cd (0.5 mg/Kg), and Zn (30 mg/Kg) in fish.     

Biomonitoring heavy metals in estuaries: a field comparison of two brown algae species inhabiting upper estuarine reaches

Biomonitoring dissolved heavy metals within estuaries,particularly at their upper reaches, frequently has to relyon several biomonitors; rarely a single species thrives allalong the salinity gradient. To properly do so, it must beestablished whether those biomonitors actually accumulateheavy metals alike. In this study, two brown seaweeds fromthe upper section of three NW Spain estuaries – the widely-known Fucus vesiculosus and the estuarine Fucusceranoides – were compared as metal biomonitors. Bothspecies were collected at five locations where they eithercoexist or live close to each other and their heavy metalcontent (Cu, Cr, Mn, Zn, Fe, Al) was measured. Analyseswere appropriately replicated for each species x locationcombination to allow a statistically reliable detection ofdifferences in bioaccumulation, with particular emphasis onthe magnitude of interspecific differences. The lack of significant differences for Cu, Mn, and Zncontents in F. ceranoides and F. vesiculosussupports the feasibility of their joint use to monitorthese metals along the estuaries. Conversely, F.ceranoides concentrated significantly higher levels of Cr,Fe, and Al than F. vesiculosus and hence combiningdata for both fucoids to monitor these elements seemsimpractical. The correlation of species differencestogether with a similar Al:Fe ratio in both weed tissue andsediment suggest that Cr, Fe, and Al tissue-burdens mightbe considerably biased by sediment retained on the surfaceof the weed. Parallel analyses of Al and/or Fe in seaweedsand sediments could serve to keep track of thisinterference and may help to combine data from both fucoidsfor monitoring elements like Cr.     

Reduced Metals Concentrations of Water, Sediment and Hyalella Azteca from Lakes in the Vicinity of the Sudbury Metal Smelters, Ontario, Canada

Hyalella azteca (Crustacea: Amphipoda), water and sediments from 12 circum-neutral lakes between Sudbury and North Bay in Ontario, Canada were sampled in August 1998 and analyzed for 10 metals including Cu, Zn, Cd, Ni, Pb, Co, Mo, V, Ba and Ti. Statistical analyses showed that concentrations of the metals in H. azteca, water and sediment differed significantly (ANOVA, P<0.05) among lakes (except for Zn and Pb in H. azteca and Mo in water). There was a trend of declining metal concentration, especially for Cu, Ni and Co (in water, Hyalella and sediment), with distance from the smelters indicating the reduced impact of atmospheric pollution. Metal concentrations of lakes (water) in the Sudbury area were found to be lower compared to data from the 1970s and 1980s indicating an improvement in water quality. Metal concentrations in field-collected amphipods compared favorably with those measured in the laboratory in animals exposed to deep-water sediments, provided metal concentrations were not extremely low (e.g., Pb) and that water chemistry differences (e.g., pH) were taken into account for some metals (especially Cd). In general bioaccumulation of metals in H. azteca was predicted better from surface water than from sediment total metal.     

洪泽湖溧河洼水生植物体内重金属调查

对洪泽湖溧河洼区域的水生植物进行了Cu、Zn、Pb、Cr和Cd等重金属元素的污染调查与监测分析,结果表明:水生植物对重金属元素的吸收与积累反映了环境中的重金属污染水平,不同水生植物对各种重金属元素的吸收富集状况具有相对一致性,即Zn>Cu>Cr>Pb>Cd。水生植物对各种重金属元素的平均富集系数大小顺序为:Cd>Cu>Zn>Cr>Pb,这与各元素迁移性强弱的顺序也是相一致的,Cd、Cu、Zn等各元素较易为植物所吸收,而Pb的移动性较差。大部分水生植物根部的重金属含量比茎叶部分高。研究表明:可以从中筛选出具有高富集作用的植物,作为修复水体或土壤重金属污染的实验植物,为植物修复作用的研究提供参考。     

Bioavailability of Metals in Fly Ash and Their Bioaccumulation in Naturally Occurring Vegetation: A Pilot Scale Study

A pilot scale study was conducted to find out the different forms of metals if fly ash (FA) and bioaccumulation of these metals in the naturally growing vegetation on FA dumps. The total, acid extractable, bioavailable and water soluble fraction of metals of Fe, Cu, Mn, Zn, Ni, Co and Pb, and their bioaccumulation coefficients (BAC) on naturally growing vegetation were determined. FA samples had a neutral pH, low electrical conductivity, low organic C and trace amounts of N and P. The relative abundance of total metals in FA were found in the order Fe ≤ ≤ Zn ≤ Ni ≤ Co ≤ Cu. The concentration of bioavailable (DTPA) metals depend on the type and nature of coal used in thermal power stations. In the water the extract solution, only Fe and Zn were found above detection limits. After one year only four species of naturally occurring herbaceous vegetation were found growing and Cynodon dactylon (grass) covered almost entire surface of the FA. Iron accumulated to the greatest extent in vegetation followed by Mn, Zn, Cu, Pb, Ni and Co. The sequence of BAC for different metals were Fe (202) ≤ Mn (90) ≤ Zn (63) ≤ Pb (49) ≤ Ni (41) ≤ Cu (24). The experimental study revealed that Cynodon grass could be used for remediation of fly ash without any amendments, as this grass species act as metal excluder type.     

Bioaccumulation of heavy metals in the wolf spider, <Emphasis Type="BoldItalic">Pardosa astrigera</Emphasis> L. Koch (Araneae: Lycosidae)

Previous studies have proposed that Pardosa astrigera L. Koch (Lycosidae) can be used as a biological indicator of heavy metal contamination in soil. In this study, we estimated the bioaccumulation levels and the bioconcentration factors (BCF) of four heavy metals (Cd, Cu, Pb, and Zn) in adult female P. astrigera collected from various field sites according to heavy metal content gradient and broods. The relationship between heavy metal content in the soil and that in spiders was different depending on the heavy metals and the broods. However, heavy metal content in P. astrigera increased with increasing heavy metal content in the soil. While the heavy metal content in the soil was in the order of Zn > Pb > Cu > Cd, its content in P. astrigera was in the order Zn > Cu > Cd > Pb. The BCF for Cd in both of the broods was distinctly higher than those of the other heavy metals evaluated. These results indicate that P. astrigera may be useful as a biological indicator of Cd soil contamination.     

A phytoremediation approach using Calamagrostis ligulata and Juncus imbricatus in Andean wetlands of Peru

Emergent plant species growing in Andean natural wetlands have shown efficient phytoremediation capabilities in wetlands polluted by acid mine drainage. However, the types and amounts of heavy metals accumulated by native plant species are not well understood. In this study, we focused on determining heavy metal concentrations and bioaccumulation factors in Calamagrostis ligulata and Juncus imbricatus. Two acid wetlands located above 3,500 m a.s.l. in Ancash, Peru were assessed. Physico-chemical parameters and heavy metals concentrations in control and experimental plant samples were measured in dry and rainy seasons. Results indicated that C. ligulata and J. imbricatus aerial parts accumulated higher amounts of Fe, Zn, As and Al. Also, bioaccumulation factors revealed notable increases in As, Pb and Al, but less so in Cd, Fe and Zn. On the other hand, physico-chemical parameters of water quality (pH, temperature, dissolved oxygen, sulphides) between inflow and outflow of wetlands indicated significant differences in the presence of metals in comparison with their maximum permissible limits. Both emergent plant species showed an accumulation of heavy metals and thus the ability to recovery of water quality in wetland outflows.     

Metal accumulation in the tissues of grass carps (Ctenopharyngodon idellus) from fresh water around a copper mine in Southeast China

Mining effluents are the main source of metals in the surrounding aquatic environment. The mining district of Purple Mountain has a history of copper mining for more than 30 years, but there is limited investigation of metal bioaccumulation in the aquatic creatures from the Tingjiang river catchment affected by the mining activities. In this study, we collected grass carps (Ctenopharyngodon idellus) from four sites, and analyzed the accumulation of chromium (Cr), nickel (Ni), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in ten tissues (scale, skin, muscle, gill, liver, kidney, fish maw, heart, stomach, and intestine) of the fish samples. Among all tissue samples, the highest concentrations (micrograms per gram wet weight) of Ni (0.263), Cu (69.2), Zn (84.0), As (0.259), Cd (0.640), Hg (0.051), and Pb (0.534) were noted in the liver, gill, and kidney tissues, whereas the highest concentrations of Cr (0.356) and Mn (62.7) were detected in the skin and intestine, respectively. These results gave a better understanding of the variability of metals distribution in different fish tissues. In comparison with the sample sites, metals (especially Mn, Cu, Zn, Ni, and Pb) in liver, gill, kidney, stomach, and intestine showed more inter-site differences than other tissues. The inter-site differences also revealed that site 1 and 2 increased fish uptake of Cu, Zn, Ni, and Pb, which may indicate that the copper mine and urban effluents contributed to high levels of these metals in aquatic environments in site 1 and 2. A potential food safety issue may emerge depending on the mining activities in this region because some metals in a few tissue samples exceeded the guideline values for human consumption of fish.     

铅锌尾矿库周边土壤重金属污染特征及环境风险

以尾矿库周边土壤为研究对象,用改进BCR法探讨Zn、Pb、Ni、Cu、Cr形态特征,用污染因子Cf和风险评价代码RAC评估环境风险。结果表明:Pb污染最重,总量是区域背景值的2倍多,污染剖面各重金属总量垂向分布均匀,污染已扩散至1 m深;5种金属均主要以残渣态存在,有效态、可交换态Pb质量占比均高于其他4种金属,与表层土壤相比,中、下层污染剖面各金属以更稳定的形态存在;Zn、Ni、Cu、Cr在表层或污染剖面土壤均存在低风险,部分点位Pb存在中度风险。     

Vertical distribution of heavy metals in soil profile in a seasonally waterlogging agriculture field in Eastern Ganges Basin

The accumulation of heavy metals in soil and water is a serious concern due to their persistence and toxicity. This study investigated the vertical distribution of heavy metals, possible sources and their relation with soil texture in a soil profile from seasonally waterlogged agriculture fields of Eastern Ganges basin. Fifteen samples were collected at ～0.90-m interval during drilling of 13.11 mbgl and analysed for physical parameters (moisture content and grain size parameters: sand, silt, clay ratio) and heavy metals (Fe, Mn, Cr, Cu, Pb, Zn, Co, Ni and Cd). The average metal content was in the decreasing order of Fe?>?Mn?>?Cr?>?Zn?>?Ni?>?Cu?>?Co?>?Pb?>?Cd. Vertical distribution of Fe, Mn, Zn and Ni shows more or less similar trends, and clay zone records high concentration of heavy metals. The enrichment of heavy metals in clay zone with alkaline pH strongly implies that the heavy metal distributions in the study site are effectively regulated by soil texture and reductive dissolution of Fe and Mn oxy-hydroxides. Correlation coefficient analysis indicates that most of the metals correlate with Fe, Mn and soil texture (clay and silt). Soil quality assessment was carried out using geoaccumulation index (I _geo), enrichment factor (EF) and contamination factor (CF). The enrichment factor values were ranged between 0.66 (Mn) and 2.34 (Co) for the studied metals, and the contamination factor values varied between 0.79 (Mn) and 2.55 (Co). Results suggest that the elements such as Cu and Co are categorized as moderate to moderately severe contamination, which are further confirmed by I _geo values (0.69 for Cu and 0.78 for Co). The concentration of Ni exceeded the effects-range median values, and the biological adverse effect of this metal is 87 %. The average concentration of heavy metals was compared with published data such as concentration of heavy metals in Ganga River sediments, Ganga Delta sediments and upper continental crust (UCC), which apparently revealed that heavy metals such as Fe, Mn, Cr, Pb, Zn and Cd are influenced by the dynamic nature of flood plain deposits. Agricultural practice and domestic sewage are also influenced on the heavy metal content in the study area.     

Heavy metal concentrations in water, sediment, and tissues of two fish species (Triplohysa pappenheimi, Gobio hwanghensis) from the Lanzhou section of the Yellow River, China

In order to assess the condition of heavy metal pollution in the Yellow River, Lanzhou section, China, and to quantify heavy metal (copper, lead, zinc, and cadmium) contents in tissues (liver, kidney, gills, and muscles) of two fish species (Triplophysa pappenheimi and Gobio hwanghensis), levels of these four metals in the water body, sediment, and tissues of the two fish were measured using inductively coupled plasma-atomic emission spectrometry. The metal levels from this study were compared with the threshold values in the guidelines of water, sediment, and food given by the National Environmental Protection Agency of China, the National Oceanic and Atmospheric Administration of America, and the National Standards Management Department of China. We found the mean concentrations of Cu, Pb, Zn, and Cd in THE water body, sediment, and muscles of two fish species were far below the values in guidelines. We also found that the type of metals present and their concentrations varied in different tissues and species. The results suggested that (1) Cu, Pb, Zn, and Cd did not contaminate the aquatic ecosystem severely and did not threaten the safety of human consumption in the Yellow River, Lanzhou section, and (2) organs that are sensitive to accumulating heavy metals may be useful to develop bioindicators for monitoring metal contamination. Considering environmental variables, further study is necessary before deciding which fish species or tissue could be the ideal bioindicators for aquatic pollution.     

Radon level and radon effective dose rate determination using SSNTDs In Sannur cave, Eastern desert of Egypt

The European eel’s swimbladder nematode, Anguillicola crassus, sampled from the Asi River (Orontes River) in Antakya (Hatay, Turkey) in May 2006 were analysed by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) for their some heavy metal (Cd, Cr, Cu, Fe, Hg, Mn, Pb and Zn) levels. The metal concentrations of the parasites were compared to different organs (swimbladder, liver, muscle and skin) of the fish hosts. The parasite contained statistically highly significantly amounts of Fe (P < 0.05). The iron level of nematode was up to 25.52 times than the muscle of its host, Anguilla anguilla. However, bioconcentration of Cd, Cr, Cu, Hg, Mn, Pb, Zn were detected in the A. crassus and it contained no statistically differences with the other tissues of its host, the eel (P > 0.05). Furthermore, no significant differences were detected in the heavy metal accumulations between the parasitized and un-parasitized fish tissues. The analysed metals (Cd, Cr, Cu, Fe, Mn, Pb and Zn) were found in fish muscle at mean concentrations under the permissible limits proposed by FAO.     

Distribution and Environmental Risk Assessment of Heavy Metal in Surface Sediments and Red Mullet (<Emphasis Type="Italic">Mullus barbatus</Emphasis>) from Algiers and BouIsmail Bay (Algeria)

BouIsmail (BIB) and Algiers (AB) are the most important bays in Algeria, where busy shipping activities and various industry complexes introduce different pollutants including heavy metals to the aquatic environment. The main goal of this study was to assess the contamination levels of heavy metals (Cd, Cr, Cu, Fe, Hg, Mn, Pb, Zn) in surface sediments and red mullet (Mullus barbatus) of the BIB and AB and to examine the possibility of the use of their enrichment factors (EFs) to track down the sources of metals (natural processes or human activity). The geoaccumulation index (I _geo) was calculated as a criterion to indicate the contamination level for each heavy metal. Moreover, geographical information systems based on spatial analysis methods (inverse distance weighting (IDW)) and statistical approaches (the principal component (PCA)) were performed to assess the spatial influences of multiple anthropogenic sources in different sampled areas. The results of both EF and I _geo revealed that the study area is exposed to various anthropogenic activities. The pollution load index (PLI) values of sediment samples in the different sites of Algiers and BIB ranged from 0.2 to 3.4 illustrating highly contaminated sediments. Significant bioaccumulation of Cd, Cu, Hg, Pb, and Zn (bioaccumulation factor >100%) were observed in muscle and liver of red mullet, suggesting potential health risks through consuming this fish species.     

Distribution of metals in aquatic edible plants: Trapa natans (Roxb.) Makino and Ipomoea aquatica Forsk

Most of the water bodies being used for the cultivation ofedible aquatic plants (Trapa natans and Ipomoeaaquatica) in Lucknow district, U.P., India, were found to becontaminated with a variety of toxic metals (Fe, Cu, Cr, Mn andPb). The concentration of metals Cr, Pb and Fe in water was muchhigher than recommended permissible limits of WHO (1995). Theedible parts of these plants bioconcentrated metals from theirsurrounding water significantly. Therefore, the present studywas planned to assess the metal concentration in edible part ofplants which was collected from various water bodies used forcultivation of these crops. Despite varying levels of metalsfound in various fruit parts of T. natans, the metalaccumulation in kernel was alarming. However, metal contentdecreased significantly in various parts after boiling thefruit. Similarly, I. aquatica also accumulatedsignificantly higher amounts of these metals in leaves, howeverthe metal accumulating potential varied considerably dependingupon level of metal contamination in the water body in which they were growing. The importance of these findings in theexploitation of these aquatic crops to meet the demand of foodand health perspectives for human beings is highlighted.