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1.
In order to show the accumulation of Cd, Pb, Cu and Zn in smokers, levels of these metals in serum were determined in 108 subjects: 32 non-smokers, 37 average cigarette smokers and 39 heavy cigarette smokers. The analysis was carried out by potentiometric stripping analysis (PSA) with the Tecator "Striptec System". Backward oxidation time of the amalgamated metals, by means of electrolysis, in a thin "film" of mercury in an electrode, gives their concentration measure. Our data showed an increase in average values of Cd and Pb in the serum of heavy smokers compared with average and non-smokers. Instead, as regards Cu and Zn, no differences were found in the two groups of smokers compared with the non-smokers used as controls. Results obtained of the Cd and Pb levels in serum are compatible with the presence of these metals in cigarette tobacco and inhaling them could contribute to disease connected with their accumulation in the human organism. For these subjects the increase in Cd values is of particular importance as it could predispose pulmonary emphysema.  相似文献   

2.
Litter accumulation in woodlands contaminated by Pb,Zn, Cd and Cu   总被引:4,自引:0,他引:4  
Summary Close to a primary lead-zinc-cadmium smelter the standing crop of litter in woodlands was found to be elevated relative to more distant sites. The total litter accumulation is similar to that from contaminated sites reported by other authors but in this case the concentrations of heavy metals are considerably lower than those reported for other sites. Evidence is provided to support the hypothesis that within the woodlands studied, litter accumulation is not closely pH dependent, but is clearly related to both cadmium and zinc concentrations in litter. Litter accumulation occurs in certain particle size ranges and fractionation shows that the weight of accumulated litter in these size ranges is highly correlated to cadmium concentrations. These results are discussed in relation to the reported possible long term effects of metal contamination on decomposition processes and the possibility of adaptation to these adverse effects.  相似文献   

3.
Abstract

Wood fuels being a renewable source of primary energy have been considered environmentally friendly. However, wood combustion in domestic boilers is a source of air pollution. The lack of a dust collection device is the reason why flue gases emit a significant load of particulate pollutants into the air, including heavy metals. The aim of this research was to assess the environmental hazard caused by both emissions of heavy metals during wood combustion in domestic boilers and their chemical forms present in fly ash.

From the various wood fuels burnt in domestic boilers, the fly ash selected for this study came from the combustion of briquettes of softwood from non-polluted areas, and from burning hardwood fuel from trees exposed to pollutants from heavy traffic. The wood fuels satisfy the quality demands determined in the EN 14961 Solid Biofuels - Fuel quality assurances. However, the concentrations of Cd, Cu, Pb and Zn in the fly ash are considerably higher than the appropriate limit values determined for soil improvers. Sequential extraction shows that Cd and Zn are associated mainly with the water leaching and carbonate fractions, regarded as mobile and bioavailable, and pose the potentially greatest hazard to the environment and human health. Cu, Mn and Pb associated with less mobile fractions may not pose a direct air quality hazard but, due to their high concentrations, medium-term and long-term effects on soils and surface and subsurface waters should be considered.  相似文献   

4.
During the 1994/1995 Antarctic summer 20 Antarctic cod (Notothenia coriiceps) of both sexes were collected at King George Island, South Shetland Islands, Antarctica, to determine the levels of Fe, Zn, Mn and Cu in muscle, liver, gonad and kidney. Metal levels were assessed using the inductively coupled plasma-atomic emission spectrometry (ICP-AES) technique. The levels of Fe, Zn, Mn and Cu observed in both sexes of N. coriiceps were significantly lower in muscle tissue than in liver, kidney and gonad; the livers of males and gonads of females had the highest levels. The differences between the sexes were significant for Zn and Mn in gonads and for Cu in liver. Despite the modest size-range of the specimens, the Cu levels in liver, muscle and kidney were significantly inversely correlated with female mass (P < 0.05) as was gonad Cu level and male body length. Fe mainly presented the highest concentrations and Cu and Mn the lowest ones. Mean muscle metal levels are similar to those of hake, cod, herring and mackerel; however, the level of Fe was slightly higher. Accumulation may occur for Fe, Zn and Mn in liver, kidney and gonad, which have higher levels than those of most prey. Received: 21 October 1997 / Accepted: 1 February 1998  相似文献   

5.
Concentrations of four metals (Cu, Zn, Pb, and Cd) in the sediments of the Anzali Lagoon in the northern part of Iran were determined to evaluate the level of contamination and spatial distribution. The sediments were collected from 21 locations in the lagoon. At each lagoon site a core, 60 cm long, was taken. The ranges of the measured concentrations in the sediments are as follows: 17–140 mg kg?1 for Cu, 20–113 mg kg?1 for Zn, 1–37 mg kg?1 for Pb and 0.1–3.5 mg kg?1 for Cd in surficial (0-20 cm) and 16–87 mg kg?1 for Cu, 28.5–118 mg kg?1 for Zn, 3–20 mg kg?1 for Pb and 0.1–3.5 mg kg?1 for Cd in deep (40–60 cm) sediments. The results of the geoaccumulation index (Igeo) show that Cd causes moderate to heavy pollution in most of the study area. Environmental risk evaluation showed that the pollution in the Anzali Lagoon is moderate to considerable and the ranking of the contaminants followed the order: Cd > Cu > Pb > Zn. Some locations present severe pollution by metals depending on the sources, of which sewage outlets and phosphate fertilizers are the main sources of contaminants to the area.  相似文献   

6.
The heavy metals, Cd, Cu, Cr, Zn, and Pb, were used to incubate healthy specimens of the freshwater mussel species, Anodonta cygnea. Afterwards, their biological fluids, either haemolymph or extrapallial fluid were analyzed for the presence of several organic constituents, known to be important for biomineralization, such as proteins, glycosaminoglycans (GAGs) and glucosamine. Proteins were subjected to further study, namely through the total amino acid determination after acid hydrolysis. The most disturbing pollutants tested seem to be Pb, Zn, and Cr, which caused highly decreased overall compositions, namely with respect to protein, and glucosamine, in comparison to the control group. This suggests that this group contributes to a decrease of the metabolic activity, and thus mineralization, in the exposed animals.  相似文献   

7.
Five heavy metals (Cd, Cu, Ni, Pb, and Zn) in river sediments from Abshineh River, Hamedan, western Iran, were fractionated by a sequential extraction procedure. Cu, Ni, Pb, and Zn existed in sediments mainly in residual fraction (mean 92%, 86%, 77%, and 65%, respectively), whereas Cd occurred mostly as organic matter (mean 41%) and exchangeable (mean 25%) fractions. The mean percent of mobile fraction of Cd, Cu, Ni, Pb, and Zn in contaminated sediments was 25, 13, 4, 24, and 10, respectively, which suggests that the mobility and bioavailability of the five metals in sediments probably decline in the following order: Cd = Pb > Cu > Zn > Ni. The metal levels were also evaluated according to the contamination factor, which revealed significant anthropogenic pollution of Cd and Pb.  相似文献   

8.
The aim of our study was to compare the sorption properties of a contaminated soil before and after two types of phytoremediation (natural phytoextraction vs. phytostabilization with dolomite limestone (DL) application). Soil from a pot experiment in controlled greenhouse conditions performed for two vegetation periods was used for the study. Lead, as the main contaminant in the studied soil, was easily desorbed by Cu, especially due to the increased affinity of Cu for soil organic matter; hence input of Cu to the studied soil can present another environmental risk in soils contaminated with other metals (such as Pb). In addition, the sorption behavior of chosen metals from single-element solutions differed from multielement solutions. The obtained results proved the different sorption behavior of metals in the single-element solution compared to the multi-element ones. Soil sorption behavior of Cd, Cu, and Zn decreased with the presence of the competitive metals; nevertheless, Pb sorption potential was not influenced by other competitive metals. Natural phytoextraction showed no significant effect on the sorption of Cd, Cu, Pb, and Zn onto the soil On the other hand, phytostabilization associated with DL application improved the soil sorption efficiency of all chosen metals, especially of Cu.  相似文献   

9.
10.
The inhibitory effects of Cd, Cu, Zn, Pb, and Fe on root elongation, contents of photosynthetic pigments, and metal accumulation in the roots and shoots of Sinapis alba were assessed. On the basis of growth inhibition metals can be arranged in a order Cu > Cd > Fe = Zn > Pb. All the metals, except Fe, were accumulated in significantly higher amount in the roots than in the shoots. Cd, Zn, Cu and Pb reduced chlorophyll a, and especially chlorophyll b content, and Zn and Pb reduced the carotenoid content, but less than that of chlorophyll a+b. The plants contained the highest concentration of Cd, and the lowest concentration of Zn.  相似文献   

11.
1. Cd-binding protein was isolated from the hepato-pancreas of carp administered CdCl2 (2 mg/kg). 2. This protein had a high absorption at 254 nm derived from Cd-mercaptide binding, and a low absorption at 280 nm derived from the absence of aromatic amino acids; the authors recognized the presence of two types. 3. The amino acid composition of the proteins was determined. The contents of cysteine residues were 34.24% and 31.90% in MT-I and -II respectively. Tyrosine, phenylalanine, tryptophan, histidine, leucine and arginine residues were absent in both types.  相似文献   

12.
重金属Cd、Zn、Cu、Pb对土壤微生物和酶活性的影响   总被引:3,自引:0,他引:3  
采用室内培养实验(25℃),研究了不同培养时间下重金属Cd、Zn、Cu、Pb(浓度分别为50,800,400,800mg.kg-1)污染对土壤微生物和酶活性的影响。结果表明,土壤蔗糖酶、过氧化氢酶和脱氢酶活性随着培养时间的增加而显著下降,在培养20d的时候达到最小值,然后酶活性缓慢升高。Cu对脲酶活性以及Cd对酸性磷酸酶和脲酶活性的抑制作用随时间增加而增加。土壤微生物生物量碳、细菌、真菌和放线菌数量随培养时间的增加均表现出先降低后升高的变化趋势。Cd和Cu对微生物生物量氮的抑制作用则随着培养时间的增加而增强,在培养30d时微生物生物量氮到达最低值,分别较培养10天减少了12.6%和16.5%。  相似文献   

13.
Adsorption of Cu, Cd, Ni, and Zn in single and multi-metal solutions by agricultural and forest soils was investigated in batch sorption experiments. The results showed significant differences in sorption capacities of the studied soils. The selectivity order was as follows: agricultural soil? top forest soil > bottom forest soil. The adsorption sequence Cu > Zn > Ni > Cd was established for the agricultural and bottom forest soil, while the order for the top forest soil was Cu > Ni > Zn > Cd. The experimental isotherms for the metal sorption were described satisfactorily by the Freundlich and Langmuir models. The competitive adsorption experiment indicated a reduction in the amount of metals adsorbed by the soils from the multi-metal solution compared to the single metal solution. Properties of the soils, such as pH, content of clay and organic matter, exchangeable bases and hydrolytic acidity, showed a significant influence on adsorption capacities of the studied soils.  相似文献   

14.
研究了污染土壤、油菜籽中Cd、Cu、Zn、Pb含量、形态分布特征和重金属富集状况及可能存在的生物毒性.结果表明,土壤中Cd、Zn、Pb以铁锰氧化物结合态、Cu以残留态占5种形态最高比例,分别为31.1%、39.3%、53.79%、46.24%;Cd、Pb交换态比例较高,为23.47%、16.32%,Cu、Zn的交换态比例较小,为3.14%、0.54%;土壤中不同重金属与各重金属形态相关关系有差别,5种重金属形态转化为有效态重金属难易程度不同;油菜籽和油菜籽壳中不同重金属累积趋势有差异,Cu易在油菜籽壳中累积,Cd、Zn、Pb易在油菜籽中累积;油菜籽中不同重金属累积率不同,Cd累积率最高,为0.56.油菜籽中重金属累积率与土壤中重金属总量呈显著负相关关系(P<0.05),土壤中重金属的形态、转化差异是此种负相关关系的主要原因;油菜籽中Cd、Cu、Pb以氯化钠态为主,分别为32.50%、22.94%、34.69%,Zn以EDTA态为主,为45.97%.油菜籽中重金属形态可能影响其毒性,但其毒性的人类膳食风险还需进一步研究证实.油菜籽中重金属形态与油菜中重金属总量相关性不好.  相似文献   

15.
16.
The concentrations of toxic trace metals in the soil samples collected from Tirupati, India, have been determined using differential pulse anodic stripping voltammetry (DPASV). The total metal concentrations of the soils in the study area were in the following ranges: 19.5 to 23.6 mg of Zn, 0.032 to 0.036 mg of Cd, 15.8 to 18.9 mg of Pb, and 19.0 to 23.4 mg of Cu per kg soil. Analysis of standard reference material IAEA-SOIL-5 indicates good accuracy. Recoveries were nearly quantitative for all elements studied. Comparison of the average metal concentration levels with world averages indicates an elevated value for Pb. The applicability of this method was crosschecked with AAS and the results were in good agreement.  相似文献   

17.
18.
Abstract

A five-step sequential extraction procedure was applied to organic-rich soil samples from five soil profiles situated 1–8 km from a zinc smelter. The partitioning of Zn, Cd, Pb, and Cu into five operationally defined fractions (exchangeable, “carbonate’’-bound, reducible, oxidizable, and residual) was studied at different soil depths down to 35cm. In the surface soil (0–1 cm) a major part of Pb and Cu was extracted in the oxidizable fraction, whereas for Zn and Cd slightly more was extracted in the ‘‘carbonate”-fraction than in the other four fractions. Extracted metal proportions in the oxidizable fraction were respectively of the order of 30%, 20%, 50%, and 80% for Zn, Cd, Pb, and Cu in the surface soil for all sites, but these proportions decreased with soil depth. In the surface soil less than 20% of all the elements were extracted in the residual fraction, but the proportions associated with this fraction generally increased with soil depth. In the C-horizon, differences in extracted proportions of Pb and Cu in the residual fraction were probably due to geochemical factors, whereas for Zn the low extracted proportion at a highly contaminated site (20%) may be due to Zn migration to the C-horizon at this site. For Cd the extracted proportions in the C-horizon were lower than for the other elements, generally below 20%, presumably because Cd is weaker in terms of its adsorption to the soil than the other elements studied. Total concentrations of the metals decreased strongly with increasing distance from the smelter, but less systematic differences were observed for their distributions among fractions. Potentially bioavailable metal proportions (exchangeable + “carbonate”-bound fraction) in the surface soil were about 50%, 60%, 20%, and 10% for Zn, Cd, Pb, and Cu, respectively. In C-horizon soil the mobility sequence Cd>Zn>Pb = Cu was generally observed. The present results indicate that the concentrations and chemical fractionation of Zn, Pb, and Cd in these soils represent a considerable risk to natural terrestrial food chains.  相似文献   

19.
High-performance ion chromatography and inductively coupled plasma–mass spectrometry methods have been applied to estimate the content of Cd, Co, Cu, Fe, Mn, Zn, and Ni in whole blood, plasma, and urine of obese and nonobese children. The study was conducted on a group of 81 Polish children of age 6–17 years (37 males, 44 females). Obese children were defined as those with body mass index (BMI) >95th percentile in each age–gender-specific group. Statistical testing was done by the use of nonparametric tests (Kruskal–Wallis's and Mann–Whitney's U) and Spearman's correlation coefficient. Significant correlations appeared for control group in plasma (Mn–Cd, Ni–Co), urine (Cu–Co), and blood (Fe–Cu), while for obese patients in plasma (Cd–Mn, Ni–Cu, Ni–Zn) and urine (Fe–Cd, Co–Mn). Sex criteria did not influence correlations between metals' content in plasma and urine of obese patients. Metals' abundance was correlated in non-corresponding combinations of body fluids. Rare significant differences between content of metals according to sex and the type of body fluids were discovered: Zn in plasma from obese patients of both sexes, and Zn, Co, and Mn in blood, Mn in plasma from healthy subjects. Negative correlations between BMI and Zn in blood, Cu in plasma, and Fe in urine were discovered for girls (control group). Positive correlation between Co content in plasma and BMI was discovered for obese boys. The changes in metals' content in body fluids may be indicators of obesity. Content of zinc, copper, and cobalt should be monitored in children with elevated BMI to avoid deficiency problems.  相似文献   

20.
We determined the concentrations of Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn in dietary supplements of marine origin. Four supplement categories were studied; algae, coral, krill, and shark cartilage. A direct mercury analyzer was used for Hg determinations while acid digestions and ICP-AES were used for Cr analysis and ICP-MS for the other trace metals. Algae are the supplements showing the highest concentrations of Pb, Cr, and Ni with respective means of 1.6 mg Pb/kg dry weight (d.w.), 3.2 Cr mg/kg d.w., and 8.0 mg Ni/kg d.w. Krill supplements have the highest levels of Cd, Cu, and Zn with 0.65 mg Cd/kg d.w., 63 mg Cu/kg d.w., and 50 mg Zn/kg d.w., respectively. Shark cartilage supplements show the highest levels of Hg and Co with mean concentrations of 160 μg Hg/kg d.w. and 73 ± 51 μg Co/kg d.w., respectively. No samples in our study exceeded the provisional tolerable daily intakes set by Health Canada, the joint committee of the World Health Organization/Food and Agricultural Organization, or the U.S. Environmental Protection Agency. Nevertheless, Ni and Pb in algae and Hg in shark cartilage may end up contributing to a very significant portion of the allowable daily intake—leaving little room for normal intake through food consumption and other exposure pathways.  相似文献   

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