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PubMed2005

Bioaccumulation and the effects of organochlorine pesticides, PAH and heavy metals in the Eel (Anguilla anguilla) at the Camargue Nature Reserve, France.

Pesticides (organochlorines-OC), polycyclic aromatic hydrocarbons (PAH) and heavy metals are toxic to fish and may be taken in through gills, skin and contaminated foods. Here we measure concentrations of OC, PAH and heavy metals, and their effects in the eel Anguilla anguilla from three locations in the Camargue Reserve in southern France. The Camargue Biosphere Reserve is the largest coastal wetland in Western Europe, and A. anguilla is a common predator at the top of the food chain. Livers and spleens were analyzed for histopathological, chemical and organo-somatic (HSI and SSI) effects. Gill, liver and spleen samples were collected for histopathological studies. Livers and muscles were sampled for metabolic parameters and persistent organic pollutant analysis. Total lipids were estimated by spectrophotometry and lipid-free residues were used in protein and glycogen analysis. OC pesticides were extracted from lipids of muscles and livers, analyzed by gas chromatography, and PAH from bile were analyzed by fixed wavelength fluorescence spectrofluorimetry. Heavy metals were measured by inductively coupled plasma with optical or with mass spectrometers. High concentrations of contaminants were found in eel tissues. La Capelière had the greatest OC and PAH concentrations; unexpected lesions in gills, livers and spleens were more common at the other sites. Liver and spleen tumors and lipidosis in livers were associated with chronic, and gill lesions with acute exposure. High pesticide and PAH concentrations and lesions in eels from the Camargue reserve demonstrate the contamination of the area. A more complete study in the Camargue reserve is necessary to better understand the impact on wildlife and humans. Also, this study suggests that eel biology must be better understood before continued use of this species as a biomonitor of polluted areas.

Analysis of Variance↗

PubMed2000

Influence of dental amalgam and heavy metal cations on in vitro interleukin-1beta production by human peripheral blood mononuclear cells.

The influence of dental amalgam and heavy metal cations on interleukin-1beta (IL-1beta) expression by peripheral blood mononuclear cells from healthy donors was studied. A marked decrease in the production of IL-1beta was caused by freshly prepared amalgam or amalgam-conditioned culture medium, but not by amalgam aged for 6 weeks. When metal cations were added as salts, Cu(2+), Hg(2+), and Ag(+) at high concentrations (33.3 and 333.3 microM) were highly inhibitory. Among other heavy metal cations, Au(3+), Pt(4+), Ni(2+), Pd(2+), but not Ga(3+) or Sn(2+), inhibited IL-1beta production in a concentration-dependent manner. Flow cytometry studies indicated that Hg(2+) and Ag(+) strongly reduced the percentage of CD14(+) cells containing IL-1beta intracellularly. As shown by Northern blot analysis, Hg(2+) inhibited the level of IL-1beta-specific mRNA by 28% at 3.3 microM and completely at 33.3 microM. Only slight inhibitory effects were induced by Cu(2+) at 33.3 microM. Interestingly, Ag(+) at a concentration of 3.3 microM increased twofold the amount of IL-1beta-specific mRNA. Our data show that IL-1beta production is altered at protein and mRNA levels by components released from fresh amalgam and by other heavy metal cations, suggesting a role of these cations in changes in the cell phenotype and IL-1-mediated cell functions.

Blotting, Northern↗

PubMed2005

Heavy metal concentrations in soil and earthworms in a floodplain grassland.

We determined accumulated heavy metal concentrations (Cd, Pb, Cu, Zn) of earthworms in moderately contaminated floodplain soils. Both soil and mature earthworms were sampled before and after flooding and earthworm species were identified to understand species specific differences in bioconcentration. Accumulated metal concentrations in floodplain earthworms differed before and after flooding. Differences in uptake and elimination mechanisms, in food choice and living habitat of the different earthworm species and changes in speciation of the heavy metals are possible causes for this observation. Regression equations taken from literature, that relate metal accumulation by earthworms in floodplains as a function of metal concentration in soil, performed well when all species specific data were combined in an average accumulation, but did not address differences in accumulation between earthworm species.

Animals↗

PubMed2004

Determination of heavy metal concentrations in street dusts in Istanbul E-5 highway.

Components and quantity of street dust are environmental pollution indicators especially in big cities. Street dust is generally composed of car exhaust gas originated particles and wind-transported particles. Heavy metals, which are found in street dust, such as Pb, Cu, Mn, Zn, Cd and Ni are significant for environmental pollution. According to the kind of vehicle in traffic, quantity and type of heavy metals vary in street dust. The use of leaded gasoline gives a boost to the importance of lead level especially in street dust even at the start of 21st century. These metals possess bioaccumulation property, and the possibility of the amount of these metals reaching a critical value and threatening human health increases the importance of this issue. In this study, street dusts have been collected from E-5 Highway from Topkapi to Avcilar regions that spans about 18 km in Istanbul, Turkey, and Pb, Cu, Mn, Zn, Cd and Ni concentrations have been detected in street dust. Twenty-two street dust samples were taken from a total of 22 different points at previously decided 14 main areas. Analyses were conducted using Leeds Public Analyst method. According to the results of this study, Pb, Cu and Zn concentrations in E-5 Highway between Topkapi and Avcilar region in Istanbul were higher than maximum concentration levels of these heavy metals in normal soil. This situation indicates that there is heavy metal pollution in the inspected area in E-5 Highway in Istanbul.

Biological Availability↗

PubMedDate not supplied

Arsenic and heavy metals in leachate from a real landfill and a laboratory landfill.

A preliminary study, based particularly on Arsenic and some heavy metals determination (Cd, Cr, Hg and Pb) in three leachate tipologies produced from municipal waste landfill plant, lab-scale aerobic landfill, lab-scale anerobic landfill was undertaken. Leachate was collected and analysed monthly; samples were homogenized and then, all heavy metals were determined after mineralization, except for Hg, determined before mineralization, due to his high volatility. In all samples pH was measured. In general we can say that low concentrations of the elements analyzed were found in all kinds of landfills considered; in particular, in the lab-scale anaerobic reactors, where low pH values have been found, we have a more considerable mobilization of As and the others heavy metals, moreover due to the behaviour of these elements.

Aerobiosis↗

PubMed2001

Heavy metals of relevance to human health induce genomic instability.

Heavy metals used in medical prostheses or present in water supplies or tobacco can build up in tissues and blood and are well known to produce toxic effects. Normally, legislative controls on the levels of these substances are determined by reference to the acute toxicity data. This paper shows that cadmium and nickel can produce delayed effects in human cells in vitro, which are characteristic of genomic instability. The effects occur even at levels where no acute toxic effects can be demonstrated. Genomic instability can be demonstrated by persistent induction of cytogenetic abnormalities and delayed cell death in progeny of cells many generations after exposure. Formerly, this syndrome has only been definitively proven to occur following irradiation, but in these experiments cell populations exposed for only 1 or 24 hours were expanded over several months, involving eight passages, and the yield of chromosomal aberrations and cell loss due to lethal mutations did not decrease. The consequences of this genomic instability are not yet known but it is possible that many of the systemic symptoms associated with exposure to low concentrations of these metals could involve delayed expression of cellular damage. It is also clear that these effects cannot be predicted from acute toxicity data.

Cadmium↗

PubMed1999

Heavy metals in three lakes in West Poland.

Concentrations of heavy metals (Ni, Cr, Co, Zn, Mn, Pb, Cd, Cu, Hg, Fe) as well as macronutrients (P, Ca, Mg) were measured in water, bottom sediments, and plants of three lakes in West Poland (southwest of Poznan). The plants collected were Nymphaea alba, Nuphar luteum, Ceratophyllum demersum, Phragmites communis, Typha latifolia, and Schoenoplectus lacustris. These plants contained elevated levels of Co, Zn, Pb, Cd, Cr, and Hg. Analyses of water and bottom sediments indicated that the lakes were polluted with Zn, Cd, Cu, and Pb and partly with Ni and Hg. Strong positive correlations were found between concentrations of Cd in water and in plants, between concentrations of Cd in bottom sediments and in plants, between concentrations of Cr in water and in plants, between concentrations of Cr in bottom sediments and in plants, and between concentrations of Fe in water and in plants, indicating the potential of plants for pollution monitoring for these metals. A negative correlation was found between biomass production and Pb and Mn content in water and Pb and Mn content in bottom sediments. Cr and Cd accumulated in plants at a higher rate from bottom sediments than from water. The accumulation rate of Fe in plant tissues was higher with an increase in Fe in water than with an increase in Fe in bottom sediments.

Biomass↗

PubMed2004

Both mercury and cadmium directly influence calcium homeostasis resulting from the suppression of scale bone cells: the scale is a good model for the evaluation of heavy metals in bone metabolism.

To examine the effects of heavy metals such as cadmium and mercury on calcium homeostasis, plasma calcium and calcitonin were measured in goldfish. Cadmium induced hypocalcemia both at 4 and at 8 days. In methylmercury-treated goldfish, the plasma calcium level increased at 2 days and then decreased at 8 days. The plasma calcitonin level increased in correspondence with the increased plasma calcium by methylmercury treatment, although cadmium did not cause a significant change. To elucidate the mechanism in detail, fish scales, which have both osteoclasts and osteoblasts and are similar to mammalian membrane bone, were used in the present study. We measured tartrate-resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) activity as respective indicators of activity in both types of cells. TRAP activity in the scales decreased by treatment of cadmium and methylmercury at 6 h incubation. Particularly, cadmium (even at 10(-13) M) significantly suppressed TRAP activity, suggesting that this system is utilized as an acute biosensor for cadmium. ALP activity decreased after exposures of 64 and 96 h, although the activity did not change after 6, 18, and 36 h. In addition, mRNA expression of the estrogen receptor and insulin-like growth factor 1, which participate in osteoblastic growth and differentiation, was less than the control values by treatment with both metals. This study demonstrates that mercury directly acts on the bone cells and influences calcium homeostasis and indicates that, in a short-term exposure, mercury has a different action from that of cadmium and induces hypercalcemia.

Acid Phosphatase↗

PubMed2004

Biosorption of heavy metals by red algae (Palmaria palmata).

The biosorption of heavy metals from aqueous solutions was investigated, using a cheap and abundant dry biomass of red algae P. palmata. The Freundlich, Langmuir and Brunauer Emmer and Teller (BET) models were used to describe the uptake of lead (pb2+), copper (Cu2+), nickel (Ni2+), cadmium (Cd 2+) and zinc (Zn2+) on P. palmata. The good fits of the Langmuir and BET models to the experimental data reflected that the sorption on P. palmata was a multi-layer sorption, in which a Langmuir equation could be applied to each layer. The highest maximum sorption capacity q(max), derived from the Langmuir model was 15.17 mg g(-1) for lead and 6.65 mg g(-1) for copper (dry weight metal/dry weight biosorbent) at a pH of 5.5-6. The affinity of metals for P. palmata was found to decrease in the order: Pb2+ > Cd2+ > Cu2+ > Ni2+. The factors influencing copper and lead uptake were found to be contact time, pH, initial concentration and temperature. Biosorption of copper and lead was a rapid process, with 70% and 100% of the respective uptakes occurring within the first 10 minutes.

Adsorption↗

PubMed2001

Redistribution index and relative binding intensity of heavy metals in salt-amended soils.

Redistribution processes of heavy metals and their binding intensity in salt-amended arid-zone soils were analyzed under saturated, field capacity and wetting-drying cycle moisture regimes. Two newly developed parameters, redistribution index and reduced partitioning parameter, were used to depict the removal/attainment of metal-amended soils from/to the fractional distribution pattern in the native soils and the relative binding intensity of metals in the amended soils, respectively. Metal-amended soils, in forms of salts approached the fractional distribution pattern in the non-amended soils with time. The rates at which the metal-amended arid-zone soils approached the fractional distribution pattern characteristic of the native soil were affected by the nature and loading levels of the metals, soil properties and time. Metals in amended soils at low loading levels approach the fractional distribution pattern characteristic of non-amended soil more rapidly than at high loading levels. The sequences of approach by various metals to the fractional distribution pattern in the native soil are as follows: Cd > Cu > Ni, Zn > Cr. Moisture regime, however, did not considerably affect the metal-amended soils' overall rates of approach to the fractional distribution pattern prevailing in the non-amended soils. The binding intensity of metals in soils was affected by the nature of metal, loading level, soil properties and time. In both non-amended and amended soils, Cr had highest binding intensity, Cd lowest and Cu, Ni and Zn intermediate. The binding intensity decreased with the loading level of the metals and increased with time. The redistribution index and reduced partitioning index can quantitatively and effectively depict the kinetics of redistribution processes of metals and their relatively binding intensity in waste-amended soils.

Desert Climate↗

PubMed2003

[Effect of heavy metals on immune reactions in patients with infertility].

BACKGROUND: Heavy metals can negatively influence reproduction because in sensitive persons they are able to alter the immune reactions including autoantibodies production. The altered immune reaction can then cause infertility. METHODS AND RESULTS: The in vitro lymphocyte reaction after stimulation with metals, the production of interferon (IFN-gamma) and antisperm antibodies in supernatants after lymphocyte stimulation in patients with infertility and with the antisperm antibodies present in their serum were investigated. The cause of antisperm antibodies presence was not determined. The diagnosis of metal intolerance was performed by the proliferation method modified for metals (Melisa). In supernatants of tissue cultures of lymphocytes without the antigen stimulation and after stimulation with mercury chloride, the in vitro production of gamma interferon and antisperm antibodies was studied by Elisa. More than 50% of patients did not tolerate mercury, iron, aluminium and silver. When the lymphocyte reaction was compared in patients with and without mercury intolerance we found that lymphocytes of patients with mercury intolerance produced less gamma interferon and more antisperm antibodies in supernatants after mercury stimulation of lymphocytes. CONCLUSIONS: In patients with metal intolerance diagnosed by the Melisa test, metal ions released from the dental materials can represent a factor, that does not cause infertility but is able to influence it negatively.

Adult↗

PubMed1996

[Nephropathies in a region contaminated by heavy metal salts and the possibilities for therapeutic and prophylactic measures].

The study of the population in the region contaminated with heavy metal salts has revealed high incidence of nephropathies even in preschool children manifesting initially in the majority of cases with hematuria. All the patients had the signs of urinary dysembryogenesis and marked membranopathological process. Long-term exposure to even small doses of heavy metals is supposed to cause nephropathy. Urinary disease arose more frequently in those genetically predisposed to renal and urinary tract affections. Because urolithiasis is a frequent result of dismetabolic nephropathy in endemic regions, it is advisable to perform active monitoring of children with environmental nephropathy using membrane-stabilizing measures. Optimal for these purpose could be xidifon. Further studies are needed to elucidate the problem of rapid elimination of heavy metals with chelating agents.

Adolescent↗

PubMed2006

Adsorption and redox reactions of heavy metals on synthesized Mn oxide minerals.

Several Mn oxide minerals commonly occurring in soils were synthesized by modified or optimized methods. The morphologies, structures, compositions and surface properties of the synthesized Mn oxide minerals were characterized. Adsorption and redox reactions of heavy metals on these minerals in relation to the mineral structures and surface properties were also investigated. The synthesized birnessite, todorokite, cryptomelane, and hausmannite were single-phased minerals and had the typical morphologies from analyses of XRD and TEM/ED. The PZCs of the synthesized birnessite, todorokite and cryptomelane were 1.75, 3.50 and 2.10, respectively. The magnitude order of their surface variable negative charge was: birnessite> or =cryptomelane>todorokite. The hausmannite had a much higher PZC than others with the least surface variable negative charge. Birnessite exhibited the largest adsorption capacity on heavy metals Pb(2+), Cu(2+), Co(2+), Cd(2+) and Zn(2+), while hausmannite the smallest one. Birnessite, cryptomelane and todorokite showed the greatest adsorption capacity on Pb(2+) among the tested heavy metals. Hydration tendency (pK(1)) of the heavy metals and the surface variable charge of the Mn minerals had significant impacts on the adsorption. The ability in Cr(III) oxidation and concomitant release of Mn(2+) varied greatly depending on the structure, composition, surface properties and crystallinity of the minerals. The maximum amounts of Cr(III) oxidized by the Mn oxide minerals in order were (mmol/kg): birnessite (1330.0)>cryptomelane (422.6)>todorokite (59.7)>hausmannite (36.6).

Adsorption↗

PubMed2004

Amperometric biosensor based on denatured DNA for the study of heavy metals complexing with DNA and their determination in biological, water and food samples.

Amperometric biosensor (BS) has been elaborated based on the stationary mercury-film electrode (SMFE) with silver support and cellulose nitrate (CN) membrane containing immobilized single-stranded DNA (ssIDNA). The sorption isotherms and ssDNA-heavy metal binding constants have been obtained with the BS. According to these data, the chosen heavy metals form the following series of binding strength with ssIDNA: Pb(II)>Fe(III)>Cd(II). It has been found that upon the competitive adsorption, there exists practically simultaneous sorption of different ions at ssIDNA containing membrane. The method of the determination of heavy metals based on preconcentration of metal ions on the BS followed by the destruction of DNA-metal complexes with ethylenediamine tetraacetate (EDTA) and voltammogram recording has been proposed. The lower limits of detectable contents are 1.0x10(-10), 1.0x10(-9) and 1.0x10(-7) mol l(-1) for Pb(II), Cd(II) and Fe(III), respectively. Heavy metals have been assayed in natural and drinking water, milk and blood serum samples even under simultaneous presence with a selectivity factor of 1:10. The effect of matrix components has been estimated.

Animals↗

PubMed2006

[Application of organic agents in remediation of heavy metals- contaminated soil].

Organic agents play an important role in the remediation of heavy metals - contaminated soil, and their introduction into practice is a promising strategy to develop an efficient solution for this remediation. This paper summarized the research advances in the application of organic agents to the remediation of heavy metals- polluted soil, including their action mechanisms, advantages and disadvantages, and factors affecting their efficiency. The commonly used organic agents, such as aminopolycarboxylic acid, organic acid, humic acid, biosurfactants, etc., were introduced, and the prospects of organic agents' application were discussed.

Environmental Pollution↗

PubMed2005

Heavy metal speciation and phytotoxic effects of three representative sewage sludges for agricultural uses.

The environmental impact of sewage sludges depends on the availability and phytotoxicity of their heavy metal. The influence of representative sludges (dewatered anaerobic, pelletization, and composted sludge) on the availability of heavy metals, and their effects on seed germination were compared. The total heavy metal concentrations were below the maximum permitted for land-applied waste and the differences among them were small. The DTPA-extracted metal concentrations were rather different. The sequential extraction of the compost showed a slight increase in Cd and Cu availability, and a decrease in the availability of Fe, Mn, Ni and Zn. Pelletization increased the availability of Ni and slightly reduced that of Cr. The dewatering sludge led to greater availability of Cr and Mn but reduced the concentration of Cd. The three different sludges also affected seed germination and root elongation in different ways. The most serious adverse effects were caused by the dewatered sludge extract.

Agriculture↗

PubMed1988

Effect of heavy metals on the growth of tissue cultures (II).

The effect of toxic concentrations of three heavy metal compounds on the growth of the secondary callus tissue of Nicotiana tabacum L. and Ruta graveolens L. was studied. The metal compounds examined were ZnSO4, NiSO4, CuSO4. The metal compounds used were placed in Murashige, Skoog (1962) and White (1943) culture medium at 10(-6) and 10(-4) M concentration, respectively, before autoclaving. The culture media containing macro- and microelements and vitamins were completed with carbon source and regulators (IAA, GA, kinetin for Nicotiana and IAA, 2, 4-D for Ruta). The cultures were kept for 4 weeks at 25 (+2) degrees C under 16/8 n light/dark conditions. The value of pH was 5.6 before the autoclave treatment. The increase in fresh weight of the secondary callus tissue was inhibited by the metal compounds applied with both plant species (to 75-87% by zinc, 7-97% by nickel, 5-98% by copper with tobacco; to 47-69% by zinc, 5-88% by nickel, 57-90% by copper with rue). The cell number and dry weight per g of callus tissue partly increased, partly decreased compared to the control in response to the heavy metal treatment. The growth values obtained with various concentrations of the heavy metals were different in the two plant species due to differences in metabolism and organization potential between them.

Copper↗

PubMed2003

Spatial and temporal observations of adsorption and remobilization of heavy metal ions in a sandy aquifer matrix using Magnetic Resonance Imaging.

The exploration of the transport and matrix interactions of heavy metal ions in the subsurface environment under natural conditions is an important field of research in environmental science and technology. Most commonly, column tests are used for a first assessment of the transport behavior. Classical column tests fall short with regard to the spatial and temporal resolution; however, these detailed data are needed for proper upscaling. Hence, providing spatially and temporally resolved data on the distribution of environmentally relevant concentrations of heavy metal ions in a water-wet aquifer matrix poses a major challenge to analytical chemistry. In this contribution, we present the results of Magnetic Resonance Imaging (MRI) studies in which submilligram quantities of heavy metal ions where either fed conventially through the column or locally injected into saturated sand packings. The subsequent transport and mobilization was monitored at a high spatial and temporal resolution. The results from a local injection show that the test design of column tests has not yet come to an end and that column tests under MRI-control may be used as a model system for, e.g., remediation techniques.

Adsorption↗