Concentration Levels Of Heavy Metals Research Articles

Heavy Metal Concentrations in Feathers of Korean Shorebirds

This study presents concentrations of zinc, manganese, copper, lead, and cadmium in the feather of five shorebird species from Yeongjong Island, Korea in the East Asian-Australian migration flyways. The objectives of this study were to determine levels of heavy metal concentrations in the feathers of shorebirds, to evaluate the pattern of heavy metal concentrations in the feather and the liver, and to examine the correlation between heavy metal concentrations in the feathers and livers. We hypothesized that difference of heavy metal concentrations will show by the breeding ground of shorebirds. Lead concentrations in dunlins (geomean = 14.8 microg/g wet weight) and great knots (20.8 microg/g wet weight) feathers were significantly higher than Terek sandpipers (3.32 microg/g wet weight); other metals were not different among shorebirds. Zinc, lead, and cadmium concentrations in the feather were correlated with the liver concentrations, but manganese and copper concentrations were not. Zinc, manganese, copper, lead, and cadmium concentrations in the feather from this study were within the range of earlier studies for wild birds, but cadmium concentrations in dunlins were higher than other studies. Because lead concentrations in livers and feathers of the Terek sandpiper were lower than in other shorebirds, we suggest that Terek sandpipers were exposed to lower lead concentrations than Kentish plovers, dunlins, and great knots on their breeding ground.

Heavy metal concentrations in marine green, brown, and red seaweeds from coastal waters of Yemen, the Gulf of Aden

The purpose of this study was to investigate the concentration levels of heavy metals in different species of the main three marine algal divisions from the Gulf of Aden coastal waters, Yemen. The divisions included Chlorophyta—green plants (Halimeda tuna, Rhizoclonium kochiamum, Caldophora koiei, Enteromorpha compressa, and Caulerpa racemosa species), Phaeophyta—brown seaweeds (Padina boryana, Turbinaria elatensis, Sargassum binderi, Cystoseira myrica, and Sargassum boveanum species), and Rhodophyta—red seaweeds (Hypnea cornuta, Champia parvula, Galaxaura marginate, Laurencia paniculata, Gracilaria foliifere, and species). The heavy metals, which included cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), Iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn), and vanadium (V) were measured by Atomic Absorption Spectrophotometer (AAs). The concentrations of heavy metals in all algal species are in the order of Fe >> Cu > Mn > Cr > Zn > Ni > Pb > Cd > V > Co. The results also showed that the uptake of heavy metals by different marine algal divisions was in the order of Chlorophyta > Phaeophyta > Rhodophyta. These heavy metals were several order of magnitude higher than the concentrations of the same metals in seawater. This indicates that marine alga progressively uptake heavy metals from seawater.

Comparing spatial dependence structures using spectral density estimators

AbstractThe aim of this work is to establish statistical methodology in order to analyze changes in the dependence structure for different spatial processes or for a process observed on a regular grid at different time moments. We propose a test statistic for testing the hypothesis $H_0:f_1=f_2$, where each $f_l$ denotes the spectral density of each process, for $l=1,2$. The test is based on a Cramer‐von‐Mises functional type test introduced in (Vilar‐Fernández and Gonzálex‐Manteiga, 2004) for the regression context. The study is developed for $L=2$, but generalizations to $L>2$ are straightforward. The application of our technique is related to biomonitoring studies which have been carried out in order to determine levels of heavy metal concentrations, taking mosses as biomonitors. Copyright © 2007 John Wiley & Sons, Ltd.

Mechanochemical remediation of heavy metals contaminated soils: Modelling and experiments

The use of mechanochemistry for the remediation of heavy metals contaminated soils is investigated. Specifically, synthetic sandy soils contaminated by Cd ( II ) , Pb ( II ) and Zn ( II ) are prepared. The degree of metal immobilization is evaluated after the soil is subjected to mechanical treatment by analyzing the leachable fraction of heavy metals obtained through the “synthetic precipitation leaching procedure (SPLP)”. For the case of soils contaminated by heavy metals concentration levels similar to field contaminated soils, their leachability is reduced to levels lower than the USEPA regulatory threshold for drinkable water. In addition impact velocity of milling media as well as impact energy and frequency are evaluated by means of a simulation model of the used milling apparatus.

Increased heavy metal tolerance of cowpea plants by dual inoculation of an arbuscular mycorrhizal fungi and nitrogen-fixer Rhizobium bacterium

Through biological inoculation technology, the bacterial-mycorrhizal-legume tripartite symbiosis in artificially heavy metal polluted soil was documented and the effects of dual inoculation with arbuscular mycorrhizal (AM) fungus and Rhizobium (N-fixing bacteria, NFB) on the host plant cowpea (Vigna sinensis) in pot cultures were investigated at six concentrations of Zn (0.0 ‐ 1000 mg/kg dry soil) and Cd (0.0 ‐ 100 mg/kg dry soil). From a number of physiological indices measured in this study, microsymbionts significantly increased dry weight, root : shoot ratios, leaf number and area, plant length, leaf pigments, total carbohydrates, N and P content of infected plants as compared with non infected controls at all levels of heavy metal concentrations. Tolerance index of cowpea plants was increased in the presence of microsymbionts than in their absence in polluted soil. Microsymbionts dependencies of cowpea plants tended to be increased at higher levels of Zn and Cd in polluted soil. Metals accumulated by microsymbionts-infected cowpea plant were mostly distributed in root tissues, suggesting that an exclusion strategy for metal tolerance widely exists in them. This study provides evidence for benefits of NFB to AM fungi in the protection of host plants against the detrimental effects of heavy metals. If so, bacterial-AM-legume tripartite symbiosis could be a new approach to increase the heavy metal tolerance of legumes plants under heavy metal polluted soil. Key word: Mycorrhiza, Vigna sinesis, heavy metals, microsymbiosis, Rhizobium.

Acidity compensation of electrochemical measurements for on-site monitoring of heavy metals

This paper presents an electrochemical instrumentation system capable of real-time in situ detection of heavy metals. A practical approach to introduce acidity compensation against changes in amplitude of the peak currents is also presented. The compensated amplitudes can then be used to predict the concentration level of heavy metals. The system uses differential pulse anodic stripping voltammetry, which is a precise and sensitive analytical method with excellent limits of detection. The instrument is capable of detecting lead, cadmium, zinc, nickel and copper with good sensitivity and precision. The system avoids expensive and time-consuming procedures and may be used in a variety of situations to help environmental assessment and control.

Transfer of selected heavy metals and radionuclides from calcareous peat to saw sedge (Cladium mariscus) in eastern Poland

The level of artificial and natural radionuclide concentration as well as heavy metal content were determined in samples of saw sedge and peat collected in the Special Protection Area of peat bogs near Chelm (Poland). Gamma- and alpha-spectrometry with proper sample preparation were used to determine natural gamma-emitters, artificial 137Cs and alpha-radiating plutonium (238Pu and 239,240Pu). Non radioactive elements were determined by AAS. Rather low level of heavy metal concentration in all samples was found, however, the transfer factors were significant. Peat contamination with artificial radionuclides (137Cs and plutonium) was low. Contrary, the concentration of these isotopes in saw sedge was higher than normally observed in non contaminated areas, what is a result of a significant transfer factor.

Heavy metals concentrations in the biophysical environment around the Ni-Cu mine and the smelter/concentrator plant, Selebi Phikwe, Botswana

The present work involves the study of heavy metals concentrations in the biophysical environment of a Ni-Cu mining and smelting area in Botswana, Africa. Samples of tailings dump, soils, particulate air matter (PAM), Imbrasia belina , and Colophospermum mopane were analysed for concentrations of heavy metals. Elements analysed were those associated with Ni-Cu mining and smelting included Cd, Cr, Co, Cu, Fe, Ni, Se and Zn, which were likely to be found in Ni-Cu orebodies and released into the biophysical environment through mining and smelting activities. Results depicted higher concentration levels of heavy metals in samples obtained close to the mine and the concentrator/smelter plant compared to samples obtained further away from where mining and smelting activities are being carried out. It is anticipated that these findings may be useful in interpreting biophysical environments where Ni-Cu mining and smelting activities are being conducted. Keywords : Selebi Phikwe, biophysical, heavy metals, environment Global Journal of Environmental Sciences Vol. 4(2) 2005: 97–110

Interspecific variation in heavy metal body concentrations in biota of Sunderban mangrove wetland, northeast India

The coastal environment of West Bengal, recognized as the most diversified and productive ecosystem among all the maritime states of India, faces organic pollution from domestic sewage and urban and industrial effluents leading serious impacts on biota. The present paper aims at providing information on concentration level of heavy metals among the tissues of benthic polychaetes, bivalve molluscs and finfishes collected from Sundarban mangrove wetland, northeast coast of India. An overall common trend in bioaccumulation was revealed with the following decreasing order: Zn>Mn>Cu>Cr>Se>Hg with few exceptions. Both species dependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in the bivalves where gill and mantle exhibited higher metal accumulation due to ion exchange property of the mucous layer covering these organs. Variability between closely related species is a reflection of different uptake rates, physiology and impact of environmental factors. The results of this analysis suggest that mollusks can play a significant role in trace metal trophic transfer studies, especially as their representatives are intertidally and subtidally ubiquitous.

Reuse of heavy metal-containing sludges in cement production

The feasibility of the replacement of raw material for cement production by heavy metal-containing sludge from surface finishing and electroplating industries was investigated. The effect of heavy metal content in the cement raw mix on the crystalline formation in cement production was also examined by XRD analyses. It was found that both sludges were applicable for the replacement of raw mix for cement production by moderate conditioning of the sludge compositions with several compositional parameters. As the replacement of raw mix by sludge was within 15%, the formation of tricalcium silicate (C 3S) phase in cement would be enhanced by the introduced heavy metals. While owing to a high level of heavy metals concentration (> 1.5%) in cement raw mix, C 3S crystalline in cement would be inhibited by a large sludge replacement (> 15%). During the sintering process, over 90% of the high volatile elements such as Pb would evaporate in high temperature, yet 90% of the less volatile elements such as Cu, Cr and Ni would be trapped in clinkers. Most of all, the results of leaching test shows that the trapped elements in hydrated samples would not leach out under acidic conditions. The reuse of heavy metal-containing sludges as cement raw material would not cause leaching hazard from sintered clinkers. Heavy metal-containing sludges thus should have the potential to be utilized as alternative raw materials in cement production.

Evaluation of heavy metals levels in the Paraı́ba do Sul River by SRTXRF in muscle, gonads and gills of Geophagus brasiliensis

It is known that fish may accumulate heavy metals through direct absorption, or via their food chain and pass them to human beings, by consumption, causing chronic or acute diseases. The metals bioaccumulation causes biochemical or pathological effects in individual fish, resulting in decrease of growth, fecundity and survival (Al-Yousuf et al., 2000). Biological strategies have evolved to detoxify metals, or to otherwise reduce the exposure of species to high concentrations of trace elements in their tissues. Total reflection X-ray fluorescence with synchrotron radiation (SRTXRF) become a competitive multi-element technique for the determination of trace elements in tissue samples (Baur et al., 2001). Since concentrations of most trace elements in tissues are lower than 100mgl , the direct determination of these elements is very difficult. In this work the concentration levels of heavy metals in selected tissues (muscle, gonads and gills) of Geophagus brasiliensis from the Paraiba do Sul River are determined using SRTXRF. This river, located in a region between the two most important urban and industrial centers of Brazil, has been changed along the last years by the human activity. Consequently, a decline in the diversity and abundance of the species has been observed.

Heavy Metals Content of Municipal Wastewater and Sludges in Kuwait

Municipal wastewater may contain heavy metals, which are hazardous to the environment and humans. With stringent regulations concerning water reuse and sludge utilization in agriculture, there is a great need to determine levels of heavy metals in liquid wastes, sludges and agricultural crops. The state of Kuwait has programs to utilize waste sludge produced at wastewater treatment plants as soil conditioner and fertilizer for greenery and agricultural development projects and to reuse treated wastewater effluents in irrigation. The common metals found in Kuwait's raw wastewater and sludge are Cd, Cr, Cu, Hg, Ni, Pb, and Zn. The effects of accumulation of heavy metals in soil are long lasting and even permanent. In this study, the variations in the concentration levels of heavy metals were measured in wastewater and sludge produced at Ardiya municipal wastewater treatment plant in Kuwait. A relationship was observed between the concentrations of heavy metals in treated wastewater and sludge used for agriculture and the level of accumulated heavy metals found in residual tissues of some crops.

Environmental chemistry and mineralogy of particulate air matter around Selebi Phikwe nickel–copper plant, Botswana

This study aimed at chemically and mineralogically characterizing whole particulate air matter (PAM) occurring at the Selebi Phikwe nickel–copper (Ni–Cu) area in Botswana, and postulating its possible environmental implications. Heavy metals concentrations in PAM samples around the Selebi Phikwe Ni–Cu plant were determined by atomic absorption spectrometry and the mineral phases identified by X-ray powder diffraction technique. The particles consisted of quartz, pyrrhotite, chalcopyrite, albite and djurleite. Concentration levels of heavy metals contained in PAM samples could be related to mineral phases present. Quite significantly is the occurrence of djurleite, which has not been found in both the orebody and surrounding soils. Djurleite polymorphs formed from secondary mineralization of chalcocite and the gases H 2S and SO 2 released from concentration/smelting processes. Possible environmental chemistry of the whole PAM based on its mineralogy at Selebi Phikwe area is discussed.

Development and optimization of a digestion method for heavy metal determination in scleractinian corals by Atomic Absorption Spectrometry (AAS).

In the last decade a great number of studies have been directed especially to the evaluation of the environmental impact of heavy metal concentration levels in coral barriers. Related to studies in scleractinian corals, many chemical techniques have been proposed to determine heavy metals but Atomic Absorption Spectrometry (AAS) is the most widely used; however, regarding sample pretreatment methods there is not a unique criterion on the requirements to obtain the precise and accurate results needed in this analysis. So, in this paper the application of several widely used pretreatment methods for digestion of corals and sediments were studied in which HNO3, HCl and HClO4 are used in different conditions (concentration, temperature, etc.), with the aim of comparing their efficiency. The method in which a combination of HNO3 and HClO4 was used resulted the most effective one. A 22 experimental design was carried out to study the influence of the HNO3 volume as well as to optimize the HNO3:HClO4 mixture. Finally the method was validated using reference certificate material (SOIL-7) using the NIST accuracy test and applying it in the analyses of different coral samples which produced results with appropriate analytical quality.

Heavy metals in biota from Sundarban Wetland Ecosystem, India: Implications to monitoring and environmental assessment

The coastal environment of West Bengal is recognized as the most diversified and productive ecosystem among all the maritime states of India. This area faces organic pollution from domestic sewage and toxic pollution from industrial effluents leading to serious impacts on water and sediment quality as well as on biodiversity. This article aims at providing information on concentration levels of heavy metals (iron, zinc, copper, manganese, cadmium, and mercury) in the tissues of a suspension feeder bivalve Macoma birmanica, whole body tissues of five gastropods (Cerithidea cingulata, C. obtusa, Telescopium telescopium, Thais lacera and Nerita articulata) and four finfishes (Liza tade, Harpodon nehereus, Trichiurus sp., and Boleopthalmus sp.) collected from water bodies of Sagar Island (22° 19′ N; 80° 03′ E), the largest delta of Sundarbans. A general trend with the following in decreasing order occurred: Fe>Zn>Mn>Cu>Cd>Hg. Both species-dependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in M. birmanica where gill and mantle exhibited higher metal accumulation due to the ion exchange property of the mucous layer covering these organs. Gastropods and finfishes were differentially selective for a range of metals, reflecting the availability of the elements in the environment and the diet and digestive physiology of these organisms. An overall elevated concentration of these metals was observed during monsoon months when low pH and salinity prevailed in the ambient medium. A continuous monitoring program is recommended to establish the studied organisms as bioindicators and to identify future changes to conserve the “health” of this fragile ecosystem.

Evaluation of Heavy Metals in Fish of the Sepetiba and Ilha Grande Bays, Rio de Janeiro, Brazil

Muscles, gonads, and liver tissues of fish caught in Sepetiba and Ilha Grande Bay were analyzed to assess levels of heavy metal concentrations of Cd, Fe, Zn, Pb, Ni, Cu, and Cr. Levels of Cr surpassed the maximum permissible concentration in muscle, followed by Zn in some species. Pb, Cu, and Cd presented concentrations above maximum permissible levels in gonads and liver only. Fe presented concentrations in viscera comparable to those of highly polluted areas, although there are no standards available for this metal. Ni was the only metal that did not present contamination in the fish tissues examined. Overall, fish caught in Sepetiba Bay showed higher metal concentrations than those from Ilha Grande Bay, but the latter also presented high metal concentrations in several samples.

Concentration Levels of Heavy and Trace Metals in the Fish and Relevant Water from Rawal and Mangla Lakes

Concentration Levels of Heavy and Trace Metals in the Fish and Relevant Water from Rawal and Mangla Lakes

Bioavailability of heavy metals in sewage sludge-amended Thai soils.

Plough and subsoil layers of two majoragricultural soil series, Rangsit and Thonburi, foundin Bangkok area of Thailand were studied fordetermining the bioavailability and solubilitybehavior of heavy metals (Cd, Cu, Zn, Mn, and Fe)following application of sewage sludge from awastewater treatment plant and a series of laboratoryexperiments. The soils contained low indigenous heavymetals while the sludge contained higher amounts ofheavy metals but in an acceptable range forapplication as plant nutrient source in agriculturalsoil. Applications of sewage sludge increased pH ofthe acid soil and available plant nutrients to thesoils. The heavy metal concentration levels in thesoils also increased. Most partitioned into easilymobile pools and later into sparingly mobile poolsfollowing 12 weeks of incubation time. Bioavailabilityforms of Cd in soil solution were low but that of Cu,Zn, and Mn remained elevated even at 12 weeks of thereaction time. Applied inorganic Zn depressed Cdsorption capacity of two soils studied but it had noeffect on Cd desorption.

Geochemistry of Surficial and Ice-rafted Sediments from the Laptev Sea (Siberia)

The Laptev Sea, as a part of the world’s widest continental shelves surrounding the Arctic Ocean, is a key area for understanding the land–ocean interaction in high latitude regions. With a yearly freshwater input of 511km3, the Lena River—one of the eight major world rivers—has an influencing control over the environment of this Arctic marginal sea, which is ice-covered during most of the year.In this paper, the first measurements are presented of the major and trace element distribution within the <20μm grain size fraction of surficial sediments and of particulate matter in new and young ice from the Laptev Sea (Siberian Arctic). The concentration and distribution of major and trace elements have been determined in 51 surficial sediment samples covering the whole Laptev Sea shelf south of the 50m isobath. Thirty-one samples of particulate matter in newly formed ice were taken during the freeze-up period in 1995.Median concentration levels of heavy metals in surficial sediments (Ni (46μg g−1), Cu (26μg g−1), Zn (111μg g−1) and Pb (21μg g−1) are within the concentration range of marine unpolluted sediments. Also the sediment-laden ice showed no indication of anthropogenic perturbation of the trace metal inventory. Spatial distribution patterns of heavy metals are mainly determined by variation of mineral composition and different fluvial sediment sources in the eastern and western Laptev Sea.The Laptev Sea shelf is cut by five north–south trending submarine valleys. Enrichment of manganese in the oxic surficial sediment layer within these valleys and the occurrence of small ferromanganese nodules are caused by a high input of dissolved and particulate Mn from the Lena River and a strong diagenetic cycling of Mn on the Laptev Sea shelf. Evidence is given that the content of As in surficial sediments is also strongly affected by diagenetic cycling. This causes surficial sediment As concentrations of more than 100μg g−1. Enrichment of Mn and As was mainly observed in the submarine valleys distant from the major river mouth. The sediment dilution due to higher sedimentation rates near the river outlets and a strong sediment re-working by ice gouging in the shallow areas are the principle causes for the absence of diagenetic accumulation in this region.During the formation of new ice scavenging of riverine suspended matter and resuspension of sediments followed by an incorporation of particles into the ice are important processes for the river–shelf–ocean transport of particulate trace elements. It could be shown that particle-loaded ice posseses the same geochemical signatures as the suspended matter and surficial seafloor sediments in the area of ice origin. This has also strong implications for the contaminant transport on the Arctic shelves and allows to use the geochemical signature of sea ice for the reconstruction of ice drift pattern within the Arctic Ocean.

Composition of aerosols in an industrialized area of Northeastern China

Surface level aerosol samples were collected utilizing conventional high volume air sampler in the highly industrialized area of Shenyang, China, located in the northeastern part of the country. Sampling was conducted in the severely polluted Tiexi District area on December 25, 1995 and again from August 23–30, 1997. The average SO2 and TSP concentrations obtained during the summer was 38 ppb and 388μg/m3, respectively. SO4 2‐, NO3 ‐ and Cl‐ were the detected water‐soluble anions with respective summerconcentrations of 3.6–10.6μg/m3, 3.2–6.5μg/m3 and 4.5–7.8μg/m3. In addition, elevated levels of heavy metals such as iron, lead, and zinc in aerosols were noted, which most likely resulted from the combustion of coal and other fuels and/or emissions associated with nearby industrial facilities. As expected, concentration levels of TSP, water‐soluble ions and heavy metals were found to increase during the winter months.