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PubMed2006

Heavy metal monitoring using bivalved shellfish from Zhejiang coastal waters, East China Sea.

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.

China↗

PubMed2005

Assessment of heavy metal concentrations in the food web of lake Beyşehir, Turkey.

The accumulation of heavy metals (Cd, Pb, Hg and Cr) was measured by atomic absorption spectrophotometry in water, sediment, plankton and fish samples collected from Lake Beyşehir, which is important bird nesting and visiting areas, and irrigation and drinking water sources. In Lake Beyşehir, the accumulation orders of heavy metals were Cd>Pb>Cr>Hg in water, Pb>Cd>Cr>Hg in sediment, Pb>Cd>Cr>Hg in plankton, and Cd>Pb>Cr>Hg in the muscles and gills of chub, carp, tench, except for the muscle of pikeperch, in which it was Pb>Cd>Cr>Hg (P<0.05). In addition to this, accumulation orders of heavy metals in the food web was also found to be water>plankton>sediment>fish tissues, except for Cr. According to international criterias and Turkish regulations, heavy metal concentrations especially Cd and Pb in Lake Beyşehir were markedly above the permissible levels for drinking water.

Animals↗

PubMed1996

Fate and effects of nutrients and heavy metals in experimental salt marsh ecosystems.

Fate and effects of the macro nutrients nitrogen and phosphorus, and the heavy metals zinc, copper and cadmium, brought into experimental salt marsh ecosystems via sediment supply, were studied over a three-year period. The supply of sediment from the Marsdiep (at a low and high rate) and from the harbour of Delfzijl (at a high rate) led to an increase of the macro nutrients and heavy metals in the top soil. The growth of the salt marsh plants Aster tripolium, Puccinellia maritima and Spartina anglica and the uptake of the macro nutrients and heavy metals by the plants was only slightly affected by the addition of sediment. A high load of sediment led to an increase in growth or in the concentrations of the macro nutrients or heavy metals in the plants at a number of sampling dates, but only minor differences between treatments were found. From a mass balance constructed over a three-year study period it could be concluded that about 50% of the macro nutrients and heavy metals were retained in the salt marsh sediment. This was equal to the retained amount of organic matter, indicating that retention of the elements was closely related to retention of organic matter. The 50% loss of the macro nutrients and heavy metals probably occurred via ebb tides after resuspension of sediment and organic matter.

Journal Article↗

PubMed2003

Accumulative heavy metal patterns in the sediment and biotic compartments of the Tisza watershed.

The paper presents data on toxic heavy metals in sediments measured after two large chemical spills on the Tisza watershed area. On the basis of the results, it is concluded that significant volume, high concentration heavy metals reached the Upper Tisza and Szamos River sections. Based on the longitudinal distribution of the heavy metals in sediments, the primary sedimentation zones and concentration increase compared with reference site was determined. Results verified arrival of fresh spills of mining origin and superimposed pollution. Regarding to chronic ecotoxicological effects, degradation and bioaccumulation rates of heavy metals priority problems are associated with arsenic, lead, mercury and cadmium in the sediments of the Tisza and Szamos Rivers after the spills of Romanian origin in 2000. Results indicate that the biological availability of the various heavy metals significantly differ along the river, particularly upstream and downstream of the Tisza Lake. The recent investigation did not identify one single sample in which muscular metal concentration of pike (Esox lucius L.) exceeded the present Hungarian consumer guidelines. The investigated pike population on the Tisza River could be divided into characteristic subgroups based on muscular tissue metal concentrations (Cd, Hg, Pb, Cu and As), depending on the bioavailability of the metalloids at the different river sections. On the basis of the data evaluation, it is concluded that the present state of pollution on Tisza River indicates the potential for deterioration and need for further biomonitoring.

Fresh Water↗

PubMedDate not supplied

Concentration of heavy metals in drinking water of different localities in district east Karachi.

BACKGROUND: Several heavy metals are present in drinking water that play important roles in the body provided their level remains within the specified range recommended by WHO. But now due to the industrialization and rapid urbanization, the problems of pollution have surfaced. This study was designed to ascertain the contents of some heavy metals and then their variations if any in drinking water in different localities of district East of Karachi, Pakistan. METHODS: Drinking water samples were collected from different sources and localities of district East of Karachi. The concentration of the heavy metals i.e. Lead, Arsenic, Copper, Iron, Mercury, Chromium, Manganese, Nickel, Cadmium and Zinc were determined by Atomic Absorption Spectrophotometry. PH was estimated by pH meter. Total dissolved solids (TDS) were calculated by formula. These concentrations of heavy metals, pH and TDS were compared with the standards set by WHO. RESULTS: Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water (Piped water, Hand pump water and Tanker water supply). Chromium was found to be raised in hand pump water. Arsenic and Mercury were not detected in any source of water. Copper, iron, manganese, cadmium and zinc were found to be within the safe limits in all the three sources of water. pH was found to be within the range of WHO recommended level in all the three sources of water. TDS was found to be elevated in hand pump water and tanker water. CONCLUSION: Concentrations of lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the three sources of water in district East of Karachi.

Arsenic↗

PubMed2003

Role of humic acid entrapped calcium alginate beads in removal of heavy metals.

Most of the available techniques for removal of heavy metals from solution such as leachates from waste sites are very expensive. The technique described in this paper is designed to study the removal of humic acid by alginate beads and the subsequent binding of the metals within the beads thus decreasing the leachability of heavy metals from a hazardous waste site. The entry of 500 mg/l humic acid into 3% calcium alginate beads in 24 h showed a distinct fluorescence as compared to the fluorescence shown by the entry of 100 and 250 mg/l of humic acid into alginate beads. Further, on treatment of calcium alginate beads containing 500 mg/l humic acid with metals such as Cu, Mn, Zn, Cr and Fe, quenching of fluorescence was noticed, which was maximum with Cu and minimum with Fe.

Alginates↗

PubMed2003

Fish macroparasites as indicators of heavy metal pollution in river sites in Austria.

This paper describes two approaches to evaluate the use of fish macroparasites as bioindicators of heavy metal pollution at selected river stretches in Austria. Firstly changes in the diversity and richness of endoparasites of the cyprinid barbel, Barbrus barbuls (L.), were tested in relation to heavy metal contents in the aquatic system. Secondly, the bioaccumulation potential of cadmium, lead and zinc was assessed in the acanthocephalan, Pomphorhynchus laevis (Miller, 1776), and compared with that in the muscle, liver and intestine of its barbel host. The present results indicated that in order to validate the role of parasite community patterns related to heavy metal pollution, more investigations on food web dynamics, interelationships between parasites and the presence/absence of intermediate hosts will be essential. Heavy metal concentrations differed significantly between the organs of barbel and P. laevis (P=0.001) with levels up to 2860 fold in the parasite. The high level of heavy metal accumulation in P. laevis compared with that in its barbel host, suggests that despite variability in the parasite infrapopulation, host mobility and feeding behaviour, P. laevis is a most sensitive indicator of heavy metals in aquatic ecosystems.

Acanthocephala↗

PubMed2003

Effects of certain heavy metals on the growth, dye decolorization, and enzyme activity of Lentinula edodes.

Various physiological parameters of Lentinula edodes (Shiitake) in the presence of nine heavy metal salts were investigated. The mycelial growth was highly sensitive to cadmium and mercury, but less sensitive to zinc, copper, and lead. This resistance can be particularly dangerous to humans in the case of edible fungi such as Shiitake because of the possible heavy metal accumulation during growth and fruiting body production. All of the tested heavy metals inhibited decolorization of the dye Poly R-478 and the production of manganese peroxidase to a greater extent than they inhibited growth. Interestingly, with the exception of iron, the addition of all heavy metal salts investigated led to the increase of laccase production. Apart from cadmium and iron, none of the heavy metals inhibited the in vitro enzyme activities in concentrations up to 3mM. The results of this study indicated the applicability of L. edodes in biosorption technologies used in the removal of toxic metals from contaminated effluents and in bioremediation technologies designed to treat complex wastes contaminated with heavy metals in addition to other xenobiotics.

Anthraquinones↗

PubMed2006

Application of random amplified polymorphic DNA (RAPD) to detect the genotoxic effect of heavy metals.

This paper presents the results of a study on the influence of lead, copper, manganese and cadmium on DNA integrity in plant cells. Plants, as biological indicators, can measure the potential effects of pollutants when they are used to measure effects of heavy metals. The genotoxicity of heavy metals in kidney-bean (Phaseolus vulgaris) seedlings was subjected to RAPD (random amplified polymorphic DNA) analysis. An RAPD 'fingerprinting' technique was used to detect DNA damage in the kidney-bean seedlings treated with two selected heavy metals at concentrations of 150 and 350 mg x l(-1). Polymorphisms became evident as the presence and/or absence of DNA fragments in treated samples compared with the untreated one. At 350 mg x l(-1), a high number of both missing bands and new amplified fragment were observed. Results suggested that a qualitative measure reflecting changes in RAPD profiles were significantly affected at higher concentrations (350 mg x l(-1)) of the tested heavy metals. A total of 467 RAPD fragments in RAPD profiles were detected by using six random primers (decamers) and 224 of these fragments showed polymorphism. There was a distinct distance between the band patterns of treated plants and the control samples when the cluster method was applied. In addition, the result derived from numerical analysis revealed a considerable distance between the band pattern of the plant samples treated with 350 mg x l(-1) heavy metals and the control sample. Finally, a comparison between untreated and treated genomes shows that RAPD analysis can be used to evaluate how the environmental pollutants modify the structure of DNA in living organisms.

DNA Fingerprinting↗

PubMed2006

Impact of sewage sludge spreading on heavy metal speciation in tropical soils (Réunion, Indian Ocean).

This study was designed to evaluate the impact of sewage sludge spreading on tropical soilborne heavy metal speciation. Sludgeborne heavy metal speciation was also assessed, and the potential mobility of the elements was classified as follows: Zn>Ni>>Cu approximately Cr. Two sequential extraction procedures were applied to study Cr, Cu, Ni and Zn speciation in control soils and sludge-amended soils. We demonstrated that sewage sludge spreading over a 2-year period did not have an impact on soilborne heavy metal concentrations but affected speciation of the most mobile fractions of Ni and Zn. Both protocols were consistent for the organic matter fractions, with an increase in Cu, Zn and Cr concentrations in the amended soil as compared to the control soil. In addition, we highlighted that the two protocols characterized different pools of organic matter and that organic compounds remained in the solid matrix after extraction. With respect to the reducible fraction, completely opposite results were obtained with the two protocols and the solid residue study revealed that the two schemes were ineffective in characterizing iron and manganese fractions.

Environmental Monitoring↗

PubMed2002

Bioconcentration of heavy metals in aquatic environments: the importance of bioavailability.

The importance of heavy metal bioavailability on the bioconcentration in aquatic biota is examined. To this purpose, mono- and multivariate statistical techniques are applied to develop correlations between heavy metal bioconcentration factor and sediment characteristics, that are expected to affect bioavailability, using a database of heavy metal concentrations in biota and sediment along with the available physicochemical characteristics. The statistical analysis shows that satisfactory correlations are obtained only when factors that affect bioavailability, such as metal oxides concentration and organic carbon content in the sediment, are taken into account.

Animals↗

PubMed1997

Heavy metals: leaching from glazed surfaces of tea mugs.

Heavy metals (zinc, lead, cadmium, iron, chromium, copper, manganese, nickel and cobalt) were found to leach from the glazed surfaces of tea mugs collected from 13 different pottery units of Khurja (U.P.) and one each from Ghaziabad (U.P.) and Calcutta (West Bengal) determined under different conditions. The leachates used were: tea at 80 degrees C, orange juice at room temperature and 4% acetic acid at room temperature, 40 degrees C and 60 degrees C, respectively. The volume (capacity) of mugs ranged between 200 and 250 ml. The duration for leaching was 24 h in each case without stirring. The concentrations of metals leached in tea at 80 degrees C were found in the range (in microgram/l): Zn, 236-730; Fe, 98-925; Cr, 62-119; Cu, 63-299; Mn, 710-2670; and Ni, 70-80 micrograms/l. The concentrations of metals leached in orange juice at room temperature were in the range (in microgram/l): Zn, 393-1262; Cd, 25-349; Fe, 122-342; Cr, 66-945; Cu, 135-853; Mn, 166-424; and Ni, 70-134 micrograms/l. The concentrations of heavy metals extracted by 4% acetic acid at room temperature were found in the range (in microgram/l): Zn, 18-192; Fe, 143-372; Cu, 51-190; and Mn, 0-48 micrograms/l; at 40 degrees C (in microgram/l): Zn, 118-837; Fe, 124-639; Cu, 230-722; and Mn, 30-63 micrograms/l and at 60 degrees: Zn, 33-900; Fe, 83-576; Cu, 90-685; and Mn, 43-778 micrograms/l, respectively.

Acetic Acid↗

PubMedDate not supplied

[Correlation between multiple antibiotic resistance and heavy-metal tolerance among some E.coli strains isolated from polluted waters].

Self-transmissible plasmids conferring multiple antibiotic resistance are wide-spread in coliforms populations. In soil and water, multiple antibiotic resistance is clearly associated with resistance/tolerance to heavy-metals (Hg2+, Cu2+, Pb2+, Zn2+, Ca2+). For different genera the genes for heavy-metals resistance are often plasmid encoded. Since these genes are clustered on the same plasmids, heavy-metals and drugs are environmental factors which exert a selective pressure for the populations of these plasmid-harboring bacteria. The aim of this preliminary study was to find possible correlation between resistance genotype determined by genetic analysis and antibiotic and heavy-metal resistance patterns of 12 E. coli strains isolated from chronically polluted waters. Antimicrobial susceptibility testing was performed for ampicillin, tetracycline, gentamycin, kanamycin, chloramphenicol, ceftazidime and cefotaxime by standard disk diffusion Kirby-Bauer method following NCCLS recommendations. These antibiotics were chosen because of their wide-spread use and importance in the treatment of Gram-negative bacterial infections. MICs values of antibiotics and heavy-metals were determined by dilution method in Mueller-Hinton broth using an inoculum of about 1-2 x 10(8) CFU/ml. The concentration range for antimicrobials and heavy-metals salts (CuSO4, CdCl2, Co(NO3)2, Cr(NO3)3, HgCl2, NiCl2 and ZnSO4) was 0.06-64 [symbol: see text] g/ml, 0.5-256 [symbol: see text] g/ml respectively. Plasmid DNA was isolated from E. coli strains by an alkaline lysis. Genetic characterization was performed by agarose gel electrophoresis and spectrophotometric analysis. All strains are multiple antibiotic resistant, 16% of them being resistant to 3, 4 and 6 antibiotics, 32% to 5 and 8% to all 7 antibiotics, respectively. Multiple tolerance to high levels of Cd2+, Cu2+, Cr3+ and Ni2+ was common among multiple antibioresistant strains. Screening for plasmids relieved the presence of several plasmids ranging from 3.8 kpb to more than 50 kpb. The phenotypic data shows the direct association between multiple antibiotic and heavy-metal resistance for E. coli strains in polluted water. Electrophoretic patterns analysis reflects the high incidence and diversity of analyzed plasmids.

Aminoglycosides↗

PubMed1990

A statewide case registry for surveillance of occupational heavy metals absorption.

The New York State Heavy Metals Registry is a legislatively mandated program through which clinical laboratories, physicians, and health facilities report state residents 18 years of age and older with elevated levels of lead, mercury, arsenic, or cadmium in blood or urine. From 1982-86, the current employer was determined for 95.9 percent of 3,309 cases. Occupational exposures in 328 companies accounted for 82.8 percent of cases. The majority of companies were reported for lead (247 companies, 75.3 percent of total) or mercury (47 companies, 14.3 percent of total). Of the 247 companies reported to the Registry for lead, the Occupational Safety and Health Administration (OSHA) inspected 18 of 98 companies (18.4 percent) in the manufacturing sector, but only one of 149 companies (0.6 percent) outside the manufacturing sector. We conclude that the Registry effectively detects companies with heavy metals exposures, and is an especially useful adjunct to OSHA inspections outside the manufacturing sector.

Adolescent↗

PubMed2003

The distributions of particulate heavy metals and its indication to the transfer of sediments in the Changjiang Estuary and Hangzhou Bay, China.

Particulate heavy metals (Cu, Pb, Cd) were measured following intensive sampling in June and October 1994 at 70 stations in the Changjiang Estuary and Hangzhou Bay, China. In the study area, particulate Cu and Pb have a similar level that is higher than the concentration of particulate Cd. Cu, Pb and Cd concentrations in suspended sediments are higher than those in bed load. In the middle of Hangzhou Bay, heavy metal concentrations in suspended sediments and bed load are similar. This may be the result of the frequent exchange between them, which is due to the strong dynamic condition. A negative relationship was observed between concentrations of heavy metals in bed load and bulk density. Fine-grained sediments were the main carriers of heavy metals. Sedimentary dynamics dominate the fate of heavy metals in these sites. The distributions of metals (especially Cu) in suspended sediments can indicate the transfer of sediments in this area.

China↗

PubMed2006

Competitive sorption and desorption of heavy metals in mine soils: influence of mine soil characteristics.

Many mine soils are chemically, physically, and biologically unstable and deficient. They are sometimes amended with sewage sludge and ashes but often contain heavy metals that increase the already high mine soils' heavy metal contents. Cd, Cr, Cu, Ni, Pb, and Zn in mutual competition were added to five mine soils (Galicia, Spain). Soil capacities for heavy metal sorption and retention were determined by means of distribution coefficients and selectivity sequences among metals. Influence of soil characteristics on sorption and retention was also examined. Retention selectivity sequences indicate that, in most of the soils, Pb is the preferred retained metal, followed by Cr. The last metals in these sequences are Ni, Cd, and Zn. Soil organic matter content plays a fundamental role in control of Pb sorption. Gibbsite, goethite, and mica influence Cr retention. Soil organic matter, oxides, and chlorite contents are correlated with K(d sigma sp medium). Heavy metals are weakly adsorbed by soils and then desorbed in high amounts. To recover these soils it is necessary to avoid the use of residues or ashes that contain heavy metals due to their low heavy metal retention capacity.

Journal Article↗

PubMed2006

[Analysis and quality assessment standard of heavy metals and arsenic in Rhizoma et Radix Notopterygii from different localities].

OBJECTIVE: Five heavy metals (Hg, Cu, Cd, Pb, Cr) and arsenic (As) contents in 57 samples of from 19 localities in Sichuan, Qinghai and Gansu of Rhizoma et Radix Notopterygii sourcing from two plants Notoperygium incusum and N. forbesii has been analyzed to evaluate the content standard of heavy metal and arsenic for drafting the herbal medicine quality. METHOD: ICP-AES method was applied to determine As, Cu, Cd, Pb, Cr and CAAS method was applied to determine Hg. RESULT: Hg can not be determined through CAAS, and little Pb was determined except in limited N. forbesii samples from certain sites, while the contents of Cu in most samples are higher than 20 mg x kg(-1). As in N. forbesii samples, and Cd in N. incisum samples are higher or approximate the limitation of related standard of medicinal plants and production. Cr varies from different localities, ranging from 0.48 to 8.36 mg x kg(-1) for N. incisum and 1.44-8.03 mg x kg(-1) for N. forbesii. CONCLUSION: Referring to the related standards of medicine and vegetable, the heavy metals and arsenic contents of Rhizoma et Radix Notopterygii samples from traditional producing areas are confirmed the propositional standard, i. e., Pb < or = 5.0 mg x kg(-1), Cd < or = 0.3 mg x kg(-1), Hg < or = 0.2 mg x kg(-1), Cu < or = 28.0 mg x kg(-1), As < or = 2.0 mg x kg(-1), and Cr < or = 1.0 mg x kg(-1). Of these five heavy metals, Cu is much over the limitation standard, which suggested that GAP base of Rhizoma et Radix Notopterygii must be selected in lower Cu environmental condition in main producing area.

Apiaceae↗

PubMed1998

Developmental abnormalities in horseshoe crab embryos caused by exposure to heavy metals

We examined the effects of heavy metals on the development of horseshoe crabs using bioassays in which embryos at different stages were exposed either continuously or for 24 h. Abnormalities included segment-defective embryos, double embryos, embryos with abnormal eye areas, and no-posterior embryos. In terms of their ability to affect normal development, the pollutants are ranked as follows: Hg >== organotin > Cr falling dots Cd > Cu > Pb > Zn. Organotin treatment was associated with a high frequency of abnormal eye embryos and Hg with segment-defective embryos. The specific cause of segment-defective malformations by Hg was investigated by using SH inhibitors and cytochalasin B, an inhibitor of microfilaments. These inhibitors induced Hg-type segment-defective embryos; thus, Hg may also act by inhibiting SH-SS exchange and blocking morphogenetic movements. Horseshoe crab embryos from Delaware Bay and Sandy Hook Bay, New Jersey, were examined for developmental abnormalities. Malformed embryos were extremely rare (<0.6%) at five beaches along Delaware Bay as well as Sandy Hook Bay, suggesting that these horseshoe crab spawning areas are relatively unpolluted by heavy metals.

Journal Article↗