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PubMed1992

[Survey of heavy metals in traditional Chinese medicinal preparations].

Traditional Chinese medicinal preparations are still widely used by natives in Taiwan. Some traditional Chinese medicine prepared with ancient formulas have been found to contain some heavy metals. There has been an occasional pediatric case admitted with heavy metal intoxication. In the last two years, we collected 11 ancient formula drug samples from the families of the patients. We detected the heavy metals with an inductively-coupled plasma atomic emission spectrometry and a graphite furnace atomic absorption spectrometry. The final result of our report reveals the problem of heavy metals in traditional Chinese medicinal preparations as being very serious.

Drugs, Chinese Herbal↗

PubMed2006

Effect of heavy metals on substrate utilization pattern, biomass, and activity of microbial communities in a reclaimed mining wasteland of red soil area.

The microbial biomass, basal respiration, and substrate utilization pattern in a copper mining wasteland of red soil area, southern China, were investigated, and indicated that soil microflora were obviously affected by heavy metals. Microbial biomass and basal respiration were negatively affected by comparatively high heavy metal levels. Two important microbial ecophysiological parameters, namely, the microbial biomass C (C(mic))/microbial biomass N (N(mic)) ratio and the metabolic quotient (qCO(2)) were significantly correlated to heavy metal stress. There was a significant decrease in the C(mic)/N(mic) ratio and an increase in the metabolic quotient with increasing metal concentration. Multivariate analysis of Biolog data for sole carbon source utilization pattern demonstrated that heavy metal pollution had a significant impact on microbial community structure and functional diversity. All the results showed that soil microbiological parameters could have great potential as sensitive, effective, and liable indicators of the stresses or perturbations in soils of mining ecosystems.

Biodegradation, Environmental↗

PubMed2006

Assessing heavy metal sources in agricultural soils of an European Mediterranean area by multivariate analysis.

According to the European Thematic Strategy for Soil Protection, the characterization of the content and source of heavy metals in soils are necessary to establish quality standards on a regional level that allow the detection of sampling sites affected by pollution. In relation to this, the surface horizons of 54 agricultural soils under vegetable crops in the Alicante province (Spain), a representative area of the European Mediterranean region, were sampled to determine the content of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn. Analytical determinations were performed by atomic absorption spectroscopy after microwave sample digestion in acid solution. Results indicated that heavy metal levels were similar to those reported by authors working on agricultural soils from other parts of the Mediterranean region, with the exception of Cu and Pb in some samples. Multivariate analysis (principal component analysis and cluster analysis) was performed to identify a common source for heavy metals. Moreover, soil properties were determined in order to characterize agricultural soils and to analyze relationships between heavy metal contents and soil properties. The content of Co, Cr, Fe, Mn, Ni and Zn were associated with parent rocks and corresponded to the first principal component called the lithogenic component. A significant correlation was found between lithogenic metals and some soil properties such as soil organic matter, clay content, and carbonates, indicating an important interaction among them. On the other hand, elements such as Cd, Cu and Pb were related to anthropic activities and comprised the second (Cu and Pb) and third principal components (Cd), designated the anthropogenic components. Generally, Cd, Cu and Pb showed a lower correlation with soil properties due to the fact that they remain in available forms in these agricultural soils. Taking into account these results and other achieved in other parts of the European Mediterranean region, it can be concluded that soil quality standards are highly needed to declare soils affected by human induced pollution. This is particularly relevant for anthropogenic metals (Cd, Cu and Pb, and in some areas also Zn). Further research in other agricultural areas of the region would improve the basis for proposing such soil quality standards.

Agriculture↗

PubMed2003

Spatial variations of heavy metals contamination in sediments from Odiel river (Southwest Spain).

The presence of heavy metal concentrations was examined in surface sediments from 27 sites within the Odiel river in the southwest Spain suffering inputs from industrial and mining activities. The interest is specially focused on the final delta located in the Odiel Natural Park, which constitutes a feeding ground of international importance for migrating birds. The behavior of 10 heavy metals (Zn, Cd, Pb, Cu, Cr, Mn, Ni, Fe, Hg) is conditioned by chemical properties of sediments such as acidity and carbonate or the presence of sulfate Very acidic sediments in the medium course of river contribute to the lower presence of metal as a consequence of leaching process. However, tidal action raises the pH in the marshes of the delta with correlative metal accumulation. In accordance with the Müller [Umschan 79 (1979) 133-149] scale for geoaccumulation index, the entire watercourse could be considered polluted by Zn and Pb, while Cu exhibits a high presence in the delta marshes of the river.

Animals↗

PubMedDate not supplied

A permeable reactive barrier for treatment of heavy metals.

Historical storage of ore concentrate containing sulfide minerals at an industrial site in British Columbia, Canada, has resulted in widespread contamination of the underlying soil and ground water. The oxidation of sulfide minerals has released significant quantities of heavy metals, including Cu, Cd, Co, Ni, and Zn, into the ground water. A pilot-scale, compost-based, sulfate-reducing permeable reactive barrier was installed in the path of the dissolved heavy-metal plume. The permeable reactive barrier uses sulfate-reducing bacteria to promote precipitation of heavy metals as insoluble metal sulfides. Monitoring over a 21-month period indicated significant removal of heavy metals within the barrier. Copper concentrations declined from a mean concentration of 3,630 pg/L in the influent to a mean concentration within the barrier of 10.5 microg/L, Cd from 15.3 microg/L to 0.2 microg/L, Co from 5.3 microg/L to 1.1 microg/L, Ni from 131 pg/L to 33.0 microg/L, and Zn from 2,410 microg/L to 136 pg/L. Within the lower half of the barrier where tidal influences were more limited and sulfate-reducing conditions were better maintained, mean treatment levels of 2.9 microg/L (Cu), 0.1 microg/L (Cd), 0.4 microg/L (Co), 2.7 microg/L (Ni), and 6.3 microg/L (Zn) were observed.

Carbon↗

PubMed2003

Heavy metals alter photosynthetic pigment profiles as well as activities of chlorophyllase and 5-aminolevulinic acid dehydratase (ALAD) in Amaranthus lividus seedlings.

Varied concentrations of PbCl2 and CdCl2 in the germinating media reduced the total chlorophyll and carotenoid contents in primary leaves of Amaranthus lividus seedlings (168 h old). When chlorophyll a and chlorophyll b contents were measured separately, greater loss of chl b than chl a under the identical conditions of heavy metal treatment was observed In addition, the loss of total chlorophyll was more than carotenoids under the same magnitude of heavy metal treatment. The effect of heavy metal treatment at germination stage was further studied on chlorophyll accumulation in primary leaves in relation to the activities of 5-aminolevulinic acid dehydratase (ALAD) and chlorophyllase. The activities of ALAD gradually diminished in response to both the heavy metals in a concentration-guided manner, while the activities of chlorophyllase did not exhibit any significant change.

Amaranthus↗

PubMed1987

Alteration of erythrocyte membrane fluidity by heavy metal cations.

Fluorescence polarization measurements were carried out on erythrocyte ghosts treated with heavy metal cations. Membranes labelled with the fluorescent lipid probe all-trans 1,6-diphenyl-1,3, 5-hexatriene (DPH) had increased DPH polarization (P) values, consistent with increased membrane lipid viscosity, when treated with 10(-3)-10(-2) M of the chloride salts of cadmium, zinc or lead for 1 hour at 37 degrees C, but not with calcium. Using cadmium as a prototype heavy metal, additional studies showed that exposure of ghosts to cadmium also increased the native protein fluorescence polarization. These increases in P values were observed at temperatures ranging from 15-40 degrees C. These data suggest that interaction of cadmium and other heavy metals with cellular membranes may alter membrane lipid and possibly membrane protein fluidity, which may contribute to abnormal cellular function.

Cadmium↗

PubMed1984

Susceptibilities of Mycobacterium fortuitum biovariant fortuitum and the unnamed third biovariant complex to heavy-metal salts.

Fifty-three clinical isolates of Mycobacterium fortuitum were tested for susceptibility to heavy-metal salts and antimicrobial agents. The isolates exhibited a bimodal distribution for several heavy metals including mercury, whose resistance is often plasmid mediated. There was a biovariant difference in the incidence of resistance, and resistance to several metal ions was often observed together. There was no apparent relationship between resistance to heavy-metal salts and resistance to antimicrobial agents such as tetracycline.

Anti-Bacterial Agents↗

PubMed2001

Factors affecting the distribution of heavy metals in wastewater treatment processes: role of sludge particulate.

The distribution of heavy metals, namely, Ag(I), Cd(II), Co(II), Cr(III,VI), Cu(II), Hg(II), Ni(II), Pb(II), and Zn(II) in 4 municipal wastewater treatment plants was evaluated as a function of several parameters including pH, COD, ionic strength and SS. Although there are variations in pH, alkalinity, COD and ionic strength, the results show that wastewater samples containing less than 5 g/L suspended solids concentration have similar characteristics. Correlations among heavy metal distribution (as the ratio between dissolved to total metals) and wastewater characteristics were attempted. Correlation between the parameters monitored and metal distribution is poor. In the case of pH, no apparent relationship could be seen. In general, increasing COD and ionic strength decreases the metal distribution. Metal distribution relies almost entirely on the concentration of solids in wastewater samples. Total metal removal in primary treatment process is lower than that reported in the literature. This could be attributed to the low average solids removal observed in the treatment plants investigated. Solids reduction at the effluent were larger than 80% and total metals removal was identical to that of the primary treatment process.

Hydrogen-Ion Concentration↗

PubMed2001

Polycysteine and other polyamino acid functionalized microfiltration membranes for heavy metal capture.

Polycysteine and other polyamino acid functionalized microfiltration membrane sorbents work exceptionally well for the removal and recovery of toxic heavy metals from aqueous streams. These are high capacity sorbents (0.3-3.7 mg/cm2) with excellent accessibility and selectivity for heavy metals, such as Hg(II), Pb(II), and Cd(II) over nontoxic components such as calcium. Polycysteine functionalized membranes work particularly well for metals such as Hg(II) and Cd(II), even in high total dissolved solids containing streams. Parameters such as permeate flow rate,feed metal concentration, and counterion (for Hg(II)) have also been found to influence sorbent behavior. For multicomponent systems, polyglutamic acid functionalized membranes have been found to selectively sorb Pb(II) versus Cd(II). Selective sorption of Cr(III) has also been observed with actual waste streams containing several heavy metals, hardness, and high sodium (2,000 mg/L). The high capacity, site accessibility, and ease of regeneration of these membrane-based sorbents make them ideal for environmental separations when volume reduction or selective recovery is required.

Absorption↗

PubMed2003

Investigation of heavy metal accumulation in Polygonum thunbergii for phytoextraction.

In this study, cadmium (II), lead (II), copper (II) and zinc (II) were determined in Polygonum thunbergii and soil from the Mankyung River watershed, Korea. Soil samples contained detectable lead (<17.5 g g(-1)), copper (<8.4 g g(-1)) and zinc (<24.5 g g(-1)), whereas cadmium was undetectable. Whole plants of P. thunbergii contained detectable lead (<320.8 g g(-1)), copper (<863.2 g g(-1)) and zinc (<2427.3 g g(-1)), whereas cadmium was detectable only in the stem (<7.4 g g(-1)) and root (<10.1 g g(-1)). Whole plant concentrations were very different for each metal, particularly in the case of zinc. The mean content of heavy metal in the whole plants increased in the order of cadmium (8.5 g g(-1))<lead (183.3 g g(-1))<copper (548.1 g g(-1))<zinc (1506.7 g g(-1)). Soil lead, copper and zinc were correlated with each metal's accumulation in the plants (lead, r = 0.841, P<0.005; copper, r = 0.874, P<0.001; zinc, r = 0.770, P<0.005). Lead content in roots and leaves was highly correlated (r = 0.5529, P<0.001), as was lead content in roots and stems (r = 0.5425, P<0.001). Mean bioconcentration factors for the aboveground tissues were 4.2 (lead), 14.8 (copper) and 27.7 (zinc), and for the underground tissues, were 22.2 (lead), 92.9 (copper) and 62.7 (zinc). After hydroponic growth, bioaccumulation coefficients were 2.0 (cadmium), 3.2 (lead), 17.2 (copper) and 13.1 (zinc) for whole plants. We considered these results as indicative of the ability of P. thunbergii plants to take up metal ions from a soil matrix contaminated with heavy metals.

Biodegradation, Environmental↗

PubMed2005

Radionuclides, heavy metals and fluorine incidence at Tapira phosphate rocks, Brazil, and their industrial (by) products.

Inorganic phosphate fertilizers may contain radionuclides, heavy metals and fluorine. This paper presents the possible environmental hazards from Tapira phosphate rocks and their (by) products (Brazil) utilized as phosphate fertilizers. The activity concentration of 238U, 234U, 226Ra and 40K in Tapira phosphate rocks is within the world range for these rock types. The 232Th activity concentration is higher than the mean reported in phosphate rocks. A value of 2184 nGy h(-1) was obtained for the exposure dose rate in Tapira phosphate deposit area, which is indicative of a high background radiation area. The flotation-separation process causes the incorporation of no more than 9%, 11% and 24% of radionuclides, heavy metals and fluorine, respectively, into the phosphate concentrate. The radionuclides and heavy metals existing in phosphate fertilizers applied in Brazilian crops according to the recommended rates, do not raise their concentration in soils to harmful levels.

Air Pollutants, Radioactive↗

PubMed2005

Prosopis juliflora--a green solution to decontaminate heavy metal (Cu and Cd) contaminated soils.

Soil and plant samples (root and shoot) of Prosopis juliflora were collected in the vicinity of metal based foundry units in Coimbatore and assessed for their heavy metal content (Cu and Cd) to ascertain the use of P. juliflora as a green solution to decontaminate soils contaminated with Cu and Cd. The results showed that Cu and Cd content was much higher in plant components compared to their extractable level in the soil. Furthermore, there exist a strong correlation between the distance of the sources of industrial units and accumulation of heavy metals in plants. Accumulation of Cd in roots is comparatively higher than that of shoots. However, in case of Cu no such clear trend is seen. Considering the accumulation efficiency and tolerance of P. juliflora to Cd and Cu, this plant can be explored further for the decontamination of metal polluted soils. On the other hand, in view of heavy metal accumulate the practice of providing foliage and pods as fodder for live stock should be avoided.

Biodegradation, Environmental↗

PubMed1999

Heavy metal music and adolescent suicidality: an empirical investigation.

This study investigated the relationship between preference for heavy metal music and vulnerability to suicide among 121 high school students. Heavy metal fans had less strong reasons for living (especially male fans) and had more thoughts of suicide (especially female fans). For a large majority, listening to music (all types) had a positive effect on mood. Overall, the results indicate that preference for heavy metal music among adolescents may be a "red flag" for increased suicidal vulnerability, but also suggest that the source of the problem may lie more in personal and familial characteristics than in any direct effects of the music. Implications for intervention and for future research are discussed.

Adolescent↗

PubMed2004

Characterization of heavy metal particles embedded in tire dust.

Tire dust is a significant pollutant, especially as a source of zinc in the urban environment. This study characterizes the morphology and chemical composition of heavy metal particles embedded in tire dust and traffic-related materials (brake dust, yellow paint, and tire tread) as measured by a field emission scanning electron microscope equipped with an energy dispersive X-ray spectrometer (FESEM/EDX). In 60 samples of tire dust, we detected 2288 heavy metal particles, which we classified into four groups using cluster analysis according to the following typical elements: cluster 1: Fe, cluster 2: Cr/Pb, cluster 3: multiple elements (Ti, Cr, Fe, Cu, Zn, Sr, Y, Zr, Sn, Sb, Ba, La, Ce, Pb), cluster 4: ZnO. According to their morphologies and chemical compositions, the possible sources of each cluster were as follows: (1) brake dust (particles rich in Fe and with trace Cu, Sb, and Ba), (2) yellow paint (CrPbO(4) particles), (3) brake dust (particulate Ti, Fe, Cu, Sb, Zr, and Ba) and heavy minerals (Y, Zr, La, and Ce), (4) tire tread (zinc oxide). When the chemical composition of tire dust was compared to that of tire tread, the tire dust was found to have greater concentrations of heavy metal elements as well as mineral or asphalt pavement material characterized by Al, Si, and Ca. We conclude that tire dust consists not only of the debris from tire wear but also of assimilated heavy metal particles emitted from road traffic materials such as brake lining and road paint.

Automobiles↗

PubMed2002

Distribution and speciation of heavy metals in surface sediments from Guanting Reservoir, Beijing.

Surface sediments in Guanting reservoir of Beijing were studied to evaluate the heavy metal pollution. The concentrations of heavy metals lie in the sequence: Zn > Pb > Cr > Cu > Ni > Co > Mo > Cd. Significant relationship (p<0.01) between the elements Cr, Ni, Co, Cu and Ni indicates that they derived from a common geological origin. While the elements Zn, Pb and Cd correlate each other. Speciation analysis showed that most of the elements were found in the residual fraction. Enrichment of the elements Zn, Pb and Cd were found in the entrance of the rivers to the reservoir and the sampling site close to the dam. The sediment size-dependent distribution and their speciation distribution in these two sites are also distinctly different from other sediment sites. All these may indicate potential pollution of elements Zn, Pb and Cd in Guanting reservoir.

China↗

PubMed2002

Effects of limestone addition and sintering on heavy metal leaching from hazardous waste incineration slag.

Hazardous waste incineration (HWI) in rotary kilns and the disposal of the residual slag on landfills play an important role in German waste treatment. In order to save disposal costs the elution behaviour of HWI-slag should be further optimised. Quality-improved slag may be disposed off on cheaper landfill sites still applying to landfill regulations. In a new process-integrated approach hazardous waste is mixed with limestone, which initiates chemical reactions with heavy metals in the rotary kiln yielding new compounds of different solubility. In this work HWI-slag/limestone mixtures are thermally treated and then examined by elution tests. Experimental data indicate that the heavy metals pertinent to landfill class assignment of a HWI-slag share a solubility minimum at a CaO-content of about 15%. Such improved HWI-slags are allowed to be disposed off on cheaper landfill sites. Furthermore, a new combination of thermodynamic calculation methods is applied to predict heavy metal solubility for different process conditions. Used models hold the opportunity to explain the tendencies of heavy metal leaching and propose plausible chemical reactions. With it, a new tool to examine the impact of temperature treatment and slag composition on heavy metal elution from HWI-slag is presented.

Calcium Carbonate↗

PubMed2001

Heavy metal pollution of river Yamuna in the industrially developing state of Haryana.

Heavy metal concentrations viz. Fe, Ni, Pb, Cd, Co, Zn in the river Yamuna flowing along the state of Haryana through Delhi have been reported selecting 16 stations covering the upstream and downstream stations for major industrial complexes of the state. While Fe, Ni and Co concentrations exceeded the maximum permissible limits prescribed for drinking all along the river, the Cd concentrations crossed the acceptable standards in Delhi downstream. The Pb concentrations declined in the eutrophicated Delhi downstream while Zn concentrations remained within desirable limits throughout. Peak concentrations were recorded in Delhi downstream for Fe and at Sonepat-Gohana downstream for Ni, Co & Zn, which matched with the type of industrial inputs viz. Iron-works and the electroplating, galvanizing & cycle industries, respectively. The status of heavy metal pollution of the river has been discussed with respect to possible impacts on human health and aquatic life.

Environmental Monitoring↗