Transfection of siRNA into <Emphasis Type="Italic">Brachionus plicatilis</Emphasis> (Rotifera)

Lake Taihu is one of the most contaminated lakes in China. Surface sediment data show that the northern area of the Lake has the worst heavy metals pollution, and high heavy metal concentrations were attributed to discharge of untreated and partially treated industrial waste water from cities to the north of the lake. To study geochemical features and pollution history of heavy metals, total content and chemical fractionations of Cu, Fe, Mn, Ni, Pb, and Zn were analyzed for core sediments from western Lake Taihu using the speciation extraction procedure, proposed by the Commission of the European Communities Bureau of Reference (BCR), together with grain size and organic carbon measurements. Results show that sediments are composed of organic-poor clayey-fine silts for Cores MS and DLS, and have similar geochemical features shown by heavy metals. Cu, Fe, Ni, and Zn mainly are associated with the residue fraction, Mn is concentrated in the exchangeable-carbonate and residue fractions, and Pb is concentrated in the Fe–Mn oxide fraction and organic-sulfide fraction. The fractions of Ni, Pb, and Zn bound to Fe–Mn oxide show significant correlations with Mn from the Fe–Mn oxide fraction, and the organic-sulfide fractions of Cu, Mn, Ni, Pb, and Zn are correlated with TOC. The increase of Cu, Mn, Ni, Pb and Zn content and percentage of extractable fractions in the upper layers of the sediments are correlated with anthropogenic input of heavy metals due to rapid industrial development. This coincides with rapid economic development in the Taihu basin since late 1970s. Heavy metals in the surface sediments have certain potential biological toxicity as shown by the higher SEM/AVS ratio.     

Fingernails as biological indices of metal exposure

Metal determination in human tissues is the most common application of biological monitoring for screening, diagnosis and assessment of metal exposures and their risks. Various biopsy-materials may be used. This paper deals with the quantitative determination of Cd, Pb, Cr, Mn, Fe, Ni, Cu, and Zn concentrations in nails of male subjects exposed to these metals alongwith their respective controls, while working in locomotive, carriage and roadways workshops, and lead battery factories. The levels of Cd, Pb, Cr, Mn, Fe, Ni, Cu and Zn in fingernails, assayed by atomic absorption spectrophotometry, were compared with their respective controls by student ‘t’ test. All the obtained values were correlated to the personal and medical history of the subjects under study. Significantly high levels of Cd, Pb, Cr, Fe, Ni, Cu and Zn were present in smokers, compared to nonsmokers. The concentrations of Cd, Pb, Cr, Mn and Fe were not significantly high in vegetarian subjects. It was also observed that there is no contribution of liquor towards nail-metal concentration. Significant correlations were observed between skin disease and Cr, Mn, Fe, Cu; hypertension and Cd, Mn, Cu; mental stress and Cd, Pb, Mn, Ni, Cu, Zn; diabetes and Cr, Mn, Ni; chest pain and Pb; respiratory trouble and Cr, Mn, Fe, Ni, Zn; tuberculosis and Zn; acidity and Cd; and ophthalmic problems and Mn, Fe, Ni, and Zn     

包头南海子湿地三种鹭鸟羽毛与环境中重金属含量的关系

于2016年7至10月采用电感耦合等离子体发射光谱法(ICP-OES),测定了内蒙古包头南海子湿地繁殖期过后的白琵鹭(Platalea leucorodia)、苍鹭(Ardea cinerea)和夜鹭(Nycticorax nycticorax)3种鹭鸟初级飞羽及环境因子(水、土壤、食物)中As、Cd、Cr、Cu、Ni、Pb、Zn、Fe、Mn、Hg 10种重金属的含量,采用单因素方差分析方法比较了不同鹭鸟种类羽毛重金属含量差异,并通过生物富集系数及Pearson相关性检验分析了羽毛与环境因子间重金属含量之间的关系,以揭示包头南海子湿地环境中重金属污染现状及生物富集特征。结果表明:(1)被检测的10种重金属中,As、Cd、Cr、Cu、Pb、Zn、Hg 7种元素在湿地环境中均已超标,尤其土壤中Fe、Zn、Cu已达到重度污染的程度。(2)不同重金属元素在鹭鸟羽毛中的含量存在差异,其中Fe元素在白琵鹭羽毛中的含量水平最高(388.77 mg/kg),Cd元素在夜鹭羽毛中的含量最低(0.12 mg/kg)。在鹭鸟羽毛中重金属含量由高至低的顺序分别为,白琵鹭Fe、Zn、Mn、Cu、Hg、Cr、Ni、Pb、As、Cd,苍鹭Zn、Fe、Cu、Cr、Ni、As、Mn、Hg、Pb、Cd,夜鹭Zn、Fe、Mn、Cu、Ni、Pb、Hg、Cr、As、Cd。除Pb和Cd元素外,其他8种元素含量在3种鹭鸟羽毛中的含量种间差异显著。(3)相关分析表明,鹭鸟羽毛中的重金属含量与环境因子中的重金属含量显著相关且呈现富集特征,为此可作为监测当地环境污染的指示性材料。     

Levels,solid-phase fractions and sources of heavy metals at site received industrial effluents: a case study

Heavy metals in the site received industrial effluents were investigated to assess the pollution levels, distribution of metal among solid-phase fractions and possible metal sources. The soil samples at different depths of 0–5, 5–25 and 25–50 cm were collected and analyzed for Fe, Mn, Cd, Zn, Cu, Ni and Pb. Among all metals, Cd content was not detected in all soil samples. The average contents of Pb and Zn are higher than the corresponding values of common range in earth crust. Meanwhile, the maximum contents of Cu and Zn are higher than those of Dutch optimum value but lower that the Dutch protection act target value. The maximum contents of Cu, Pb and Zn are higher than the average shale value. The most investigated heavy metals are mostly found in the potentially labile pool (>50.0%) including metal bound to carbonate, Fe/Mn oxides, or organically fractions. Enrichment factor (EF) in combination with multivariate analysis including principal component analysis (PCA) and hierarchical cluster analysis (HCA) suggest that Mn and Ni associated with Fe in the soil samples were primarily originated from lithogenic sources. Pb was largely derived only from anthropogenic source, while Cu and Zn in the soil samples were controlled by the mixed natural and anthropogenic sources. These results suggest that discharging the industrial effluents into dumping site increased pollution level of Pb, Zn and Cu as well as enhanced their potentially labile pool that may be responsible for occurring potential toxic impacts on environmental quality.     

Trace elements in aerial parts and rhizosphere of <Emphasis Type="Italic">Thymus pannonicus</Emphasis> All.

This paper brings out the results of the study on the levels of selected trace elements (Cu, Fe, Mn, Zn and Cr) in aerial parts of Thymus pannonicus All. (Lamiaceae) and rhizosphere soil from twelve locations in Serbia. Prior to assays by flame and flameless atomic absorption spectrometry, samples were subjected to microwave-assisted acid digestion. Real and potential acidity of soil samples were also measured. Obtained results for soil samples, although slightly higher for some elements (Cu: 12.38–45.18 mg/kg; Fe: 22102–46193 mg/kg; Mn: 776.95–4901.27 mg/kg; Zn: 62.27–214.02 mg/kg; Cr: 48.86–69.13 mg/kg), were found to fit into biogeochemical background. Element contents in plant samples differed depending on collecting site (Cu: 5.26–14.07 mg/kg; Fe: 25.92–1454.07 mg/kg; Mn: 89.29–278.25 mg/kg; Zn: 1.81–10.64 mg/kg; Cr: 1.11–3.51 mg/kg), which can be partly explainable by different nutrient availability influenced by soil acidity. Zinc levels in T. pannonicus were below expected and seem to be strongly influenced by plant physiological properties.     

浙江油茶产地土壤和果实金属元素含量特征

为探讨油茶(Camellia oleifera)产地土壤和油茶果实中金属元素分布和富集特征,在油茶果实成熟期,对浙江5个油茶产地土壤及油茶果实中金属元素进行污染分析和富集能力评价.结果表明,浙江油茶产地土壤中Pb、Cr、Cd、As、Hg、Ni、Cu和Zn含量低于农用地土壤污染风险筛选值,综合污染等级为安全.个别产区常山...     

Fas- and Mitochondria-Mediated Signaling Pathway Involved in Osteoblast Apoptosis Induced by AlCl<Subscript>3</Subscript>

The concentrations of 13 elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn) were determined in several samples of native (wild) naturally growing and cultivated blueberry fruits. The total metal contents after mineralization were analyzed by inductively coupled plasma optical emission spectrometry. Reliability of the procedure was checked by the analysis of the certified reference materials Mixed Polish Herbs (INGT-MPH-2) and Leaves of Poplar (NCS DC 73350). In the fruits collected in the forest (wild blueberries), higher contents of Ca, Na, and Mg as well as Mn and Zn were observed. Similar levels of Cu, Cr, Fe, and Ni were detected in both wild-growing and cultivated plants. The significantly higher content of Fe and Cd in cultivated blueberries was connected with the content of these metals in soil samples collected from the same places. The metal extraction efficiency by hot water varied widely for the different blueberries (wild or cultivated) as well as their form (fresh or dried).     

Insight into the pattern of heavy-metal accumulation in lichen thalli

BackgroundHeavy metals that pass through the plasmalemma are expected to influence on lichen metabolic processes; however, lichens may tolerate high concentrations of metals by sequestrating them extracellularly. Heavy metal accumulation level fundamentally determine the success of lichens in the colonisation of polluted sites; however, the proportions between extra- and intracellular metal concentrations in lichen thalli are still poorly recognized. In this study metal accumulation patterns of selected toxic trace elements, i.e. Pb, Cd, and micronutrients, i.e. Zn, Cu and Ni, in Cladonia cariosa thalli were recognised in relation to extra- and intracellular fractions.MethodsThe intracellular and total concentrations of Zn, Pb, Cd, Cu and Ni in lichen thalli collected from eleven variously polluted sites were determined by means of atomic absorption spectrometry. Additionally, organic carbon and total nitrogen contents as well as pH of soil substrate were measured.ResultsThe accumulation patterns differed between studied metal elements; the major part of Zn, Pb and Cd loads was accumulated extracellularly, whereas Cu and Ni accumulation was mostly intracellular. Like toxic trace elements, Zn was accumulated mainly extracellularly at high polluted sites. The non-linear models most reliably reflect relationships between intracellular and extracellular metal contents in C. cariosa thalli. The intracellular contents of Zn, Pb, Cd and Cu increased slower at higher than at lower extracellular concentrations. Moreover, at higher total concentrations of elements in the thalli, their extracellular proportions were markedly increased.ConclusionThe results suggest that in the face of extreme Zn-enrichment, lichens demonstrate the ability to accumulate the excess of Zn outside the cells. Therefore, it can be concluded that metal accumulation depend not only on the element but also on its abundance in the environment and direct availability for lichens. The studied species showed a defence against excessive intracellular accumulation when a given element is in excess. Such capability may facilitate the colonization of extremely polluted sites by certain pioneer lichens.     

Proximate and Elemental Composition of <Emphasis Type="Italic">Chamelea gallina</Emphasis> from the Southern Coast of the Marmara Sea (Turkey)

The venerid clam Chamelea gallina is a popular and economic foodstuff around the Mediterranean countries especially in Italy, Spain, and France. The aim of this study is to evaluate the nutritional quality of striped venus of Southern Marmara. Samples were harvested seasonally at five stations and analyzed to determine meat yield, proximate, and elemental composition. According to the results, meat yield ranged from 20.24% to 29.94%. Means of water, protein, lipid, and ash content were 67%, 10.12%, 2.57%, and 1.66%, respectively. The mean concentrations (mg/kg wet weight) of elements in tissues are as follows: B: 2.37–4.24; Cr: 0–0.76; Co: 0–0.43; Cu: 0.71–5.30; Mn: 0.30–5.94; Zn: 13.08–77.76; Ni: 0–1.22; Fe: 2.46–114.22; Al: 1.23–75.49; Pb: 0.18–3.24; Ba: 0.66–15.97; Cd: 0.04–0.69. Among the reported metal levels, only Pb and Zn in two stations exceeded the maximum critical concentrations enforced by Turkish legislation and European Commission. Therefore, we report that striped venus from Southern Marmara Sea, in general, are safe for human consumption; nonetheless, Pb and Zn levels should be closely monitored in the future.     

广西马尾松人工林对重金属元素的吸收、累积及动态

探讨了广西马尾松人工林对重金属Cu、Zn、Mn、Pb、Ni、cd元素的吸收、累积及动态。结果表明:马尾松林地土壤层(0~60 cm)中重金属元素Cu、Zn、Mn、Pd、Ni、Cd的平均含量,分别为23.02,24.46,235.46,5.93.8.45和0.14 mg·kg-1,储量大小依次为Mn>Zn>Cu>Ni>Pb>Cd。马尾松林不同组分中,重金属元素的含量范围分别为Cu 2.97-13.47,Zn 12.09-42.93,Mn 143.14-751.78,Pd 2.87-25.12,Ni 0.19-25.05和Cd 0.16~1.24 mg·kg-1,对土壤6种重金属元素富集能力的大小依次为Cd>Mn>Pb>Zn>Ni>Cu。马尾松林中,重金属元素的总储量为39.791kg·hm-2,其中Mn、Zn、Pb、Cu、Cd、Ni元素的储量分别为34.047,3.351,1.226,0.874,0.245,0.084 kg·hm-2,各组分中重金属元素储量的空间分布为干>皮>根>叶>枝。Cu、Zn、Mn、Pd、Ni、Cd的周转期分别为13.9、7.0、3.1、20.4、2.1、12 a,流动系数为Ni>Mn>Zn>Cd>Cu>Pb。     

Serum and tissue levels of six trace elements and copper/zinc ratio in patients with cervical cancer and uterine myoma

The aim of this study is to investigate the relationship between trace elements and the incidence of cervical cancer. Tissue and serum levels of six elements (Cu, Zn, Fe, Mn, Ca, and Se) and the Cu/Zn ratio in 40 cases of patients with cervical cancer, 30 cases of uterine myoma, and 50 healthy subjects were measured by atomic absorption spectrophotometry; the selenium content was determined by atomic fluorescence spectrometry. The results showed that the tissue contents of Zn, Se, and Ca were significantly lower and the Cu and Fe concentrations and Cu/Zn ratio were significantly higher in cervical cancer tissue than that for paired nonlesion tissue (p<0.02 and p<0.001, respectively). The serum levels of Zn, Se, Ca, and Fe were lower and Cu and Mn levels and Cu/Zn ratio were higher in patients with cervical cancer than in healthy subjects (p<0.01 and p<0.001, respectively) and in the uterine myoma group compared with healthy subjects (p< 0.05–0.001). There are no significant differences in the contents of six elements and the Cu/Zn ratio between uterine myoma tissue and paired nonlesion tissue. The results showed also that the Fe level and Cu/Zn ratio were significantly higher and the Zn and Se levels were significantly lower in cervical cancer tissue than in uterine myoma tissue (p<0.01 and p<0.001, respectively). The serum Cu level and Cu/Zn ratio were significantly higher in the cervical cancer group than the uterine myoma group (p<0.01). Data were also analyzed using multivarate logistic regression. After adjustment for age, occupation, life habit, and other covariates for the development of cervical cancer, the odds ratios were 22.64 (95% confidence interval [CI]: 5.64–90.88, p=0.001) for Cu, 0.11 (95% CI: 0.034–0.373; p=0.005) for Zn, and 0.60 (95% CI: 0.36–0.99, p=0.01) for Se. Thus, the serum and tissue levels of Cu increase and the deficiency of Zn and Se may be risk factors for the development of cervical cancer.     

Content of heavy metals in thalli of the lichen <Emphasis Type="Italic">Hypogymnia physodes</Emphasis>: Sources of heterogeneity

Size and reproductive traits of thalli of the epiphytic lichen Hypogymnia physodes (L.) Nyl. and concentrations of heavy metals (Cu, Fe, Cd, Zn, Pb) in them were determined in the region of the Middle Ural Copper Smelting Plant, in two contrast zones of atmospheric pollution. The nonuniformity of populations in both size and reproductive traits and metal concentration was demonstrated. A high heterogeneity of subpopulations growing on different phorophytes was revealed. It is recommended to optimize data collection by taking samples from a larger number of trees (20–30) at a smaller number of thalli (10–20) from one phorophyte.     

Differences in Trace Metal Concentrations (Co, Cu, Fe, Mn, Zn, Cd, and Ni) in Whole Blood, Plasma, and Urine of Obese and Nonobese Children

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.     

Trace elements in the hydrologic cycle of a forest ecosystem

Summary Concentrations of Cu, Fe, Mn, and Zn were measured in bulk atmospheric precipitation, throughfall, stemflow, and soil solutions at 10−, 15−, 25−, and 30-cm depths, in aEucalyptus globulus forest in the Berkeley hills, California, during the 1974–75 wet season after each main storm event. Litter and plant samples were analyzed. There was some similarity in the behavior of Cu, Fe, and Zn, but Mn behaved differently. Mn and Zn are largely deposited on the forest canopy by impaction during dry-deposition episodes, whereas most of the Cu and Fe input occurs in rain. For the hydrologic components measured, concentrations of Cu and Fe increase in the order: precipitation<throughfall<stemflow <soil solutions. For Zn the order is: precipitation<stemflow<throughfall<soil solutions. Concentrations of Cu, Zn, and Fe in the soil solution fluctuate with downward movement of wetting fronts and are negatively correlated with pH. Concentrations of Fe in soil solution are about 10 times greater than those of throughfall and stemflow; the corresponding relative differences for Cu and Zn were much less. Plant uptake of Mn exceeds that of Cu, Zn, and Fe. The increases in Mn concentrations from precipitation to throughfall and stemflow are much greater than those for Cu, Zn, and Fe because precipitation has very low Mn concentrations. The concentration series for Mn is: precipitation<soil solutions<throughfall<stemflow. Concentrations of Mn in the soil solution are negatively correlated with pH. During the dry summer Mn accumulates in the soil, but is quickly flushed by early rains of the wet season.     

刺楸年轮中重金属含量动态变化及富集特性

为探索刺楸对受污染土壤重金属的富集和修复效应, 以南京栖霞山的乡土树种刺楸及其根际周边土壤为研究对象, 截取其根基部年轮盘及根际土壤样本, 采用ICP-AES法测定年轮及土壤样本中重金属(Cu、Cd、Cr、Mn、Ni、Pb、Zn)元素含量。结果表明: 栖霞山样地中的土壤受Mn、Pb和Zn污染最为严重, 存在Cu、Cd、Mn、Pb、Zn元素的高度复合污染, Cd、Cr、Cu、Ni、Zn在土壤和年轮中存在相关性, Mn和Pb则没有表现出明显的相关性; 刺楸修复受Cd、Mn、Pb、Zn污染的土壤效果并不显著, 更适用于Cr、Cu、Ni污染的土壤修复; 鉴于Cu元素含量变化特征, 刺楸也可以作为反映当地污染历史的记录载体; 刺楸年轮中的重金属元素之间存在交互作用, 其中Cd与Zn元素含量高度相关(r=0.984, p<0.01), 在刺楸年轮吸收重金属元素的过程中, Cu与Cd、Cr、Mn、Zn元素具有协同作用, Mn元素对其他元素有一定的拮抗作用。     

Application of focused-microwave wet digestion to the determination of trace metals in human gallstones by ICP/AES.

We propose an analytical digestion method for trace metal determination (Co, Cr, Cu, Fe, Mn, Ni and Zn) in gallstones, in an attempt to facilitate detection of their origin. The method consists of sample digestion with HNO3 and H2O2 by means of focused microwave. Metals are quantified by inductively coupled plasma atomic emission spectroscopy. The effect of calcium concentration in the analytical solutions was studied. Cu, Fe, Mn and Zn were detected in all the samples analysed and the highest concentrations were obtained for Cu and Fe, especially in black-pigmented gallstones. The reproducibility in terms of %RSD, determined in the gallstones with the lowest metal content, was below 5% for Cu, between 10% and 15% for Mn and Zn and up to 25% for Fe.     

Trace metal content in the seagrass Cymodocea nodosa: Differential accumulation in plant organs

Differences in the accumulation of seven metallic elements, including micronutrients (Cu, Fe, Mn, Ni and Zn) and non-essential elements (Cd and Pb) among plant organs (leaves, roots and rhizomes) were examined in the seagrass Cymodocea nodosa. Samples were taken from two coastal bays (Catalonia, Western Mediterranean), with a total of nine sampling sites encompassing different levels of metal availability. Metal content was generally higher in uptake organs (leaves and roots) than in rhizomes. However, accumulation in leaves and roots varied between elements. While Cd, Mn and Zn preferentially accumulate in leaves, Fe and Pb accumulate in roots and Cu and Ni in both. There were common spatial (between sites) trends in Cd, Mn, Cu and Zn accumulation in the three organs. However, these spatial trends varied according to the organ considered in the case of Fe, Pb, and Ni. Therefore, assessment of within-plant variability is strongly recommended prior to the use of C. nodosa for biomonitoring purposes, at least for Fe, Pb, and Ni.     

Toxic and Essential Mineral Elements Content of Black Tea Leaves and Their Tea Infusions Consumed in Iran

The metal contents of eleven black tea samples, four cultivated in Iran and seven imported, and their tea infusions were determined. Twelve elements consisting toxic metals (Al, As, Pb, Cr, Cd, and Ni) and essential mineral elements (Fe, Zn, Cu, Mn, Ca, and Mg) were analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Al, Ca, Mg, and Mn ranged in black tea leaves at mg g⁻¹ levels, while Cr, Fe, Ni, Cu, Zn were at μg g⁻¹ levels. Analysis of variance showed no statistically significant differences among most elements determined in cultivated and imported black teas in Iran except for Ni and Cu. The extraction efficiency of each element into tea infusions was evaluated. The solubility of measured metals in infusion extracts varied widely and ranged from 0 to 59.3%. Among the studied elements, Cr, Pb, and Cd showed the lowest rates of solubility and Ni had the highest rates of solubility. The amount of toxic metals and essential mineral elements that one may take up through consumption of black tea infusion was estimated. The amount of realizing each element into tea infusions and acceptable daily intake, for safety consumption of black tea, was compared.     

Alfalfa genotypes differ in their ability to tolerate zinc deficiency

Response of 13 alfalfa (Medicago sativa L.) genotypes to varied Zn supply (+Zn: 2 mg kg⁻¹ soil, −Zn: no added Zn) was studied in a pot experiment under controlled environmental conditions. Plants were grown for four weeks in a Zn-deficient siliceous sandy soil. Plants grown at no added Zn showed typical Zn deficiency symptoms i.e. interveinal chlorosis of leaves, yellowish-white necrotic lesions on leaf blades, necrosis of leaf margins, smaller leaves and a marked reduction in growth. There was solute leakage from the leaves of Zn-deficient plants, while no solute leakage from Zn-sufficient plants. The ratios of P:Zn, Fe:Zn, Cu:Zn and Mn:Zn in Zn-deficient plants were extremely high compared with Zn-sufficient plants indicating disturbance of P:Zn, Fe:Zn, Cu:Zn and Mn:Zn balance within plant system by Zn deficiency. Genotypes differed markedly in Zn efficiency based on shoot dry matter production. Alfalfa genotypes also differed markedly in P:Zn ratio, Cu:Zn ratio and Fe:Zn ratio under —Zn treatment. The shoot dry weight, shoot:root ratio, chlorophyll content of fresh leaf tissue, solute leakage from the leaves, Zn uptake and distribution of Zn in shoots and roots were the most sensitive parameters of Zn efficiency. Zn-efficient genotypes had less solute leakage but higher shoot:root ratio and higher Zn uptake compared with Zn-inefficient genotypes. Under —Zn treatment, Zn-inefficient genotypes had less Zn partitioning to shoots (33–37%) and more Zn retained in roots (63–67%), while Zn-efficient genotypes had about equal proportions of Zn in roots (50%) and shoots (50%). This revised version was published online in June 2006 with corrections to the Cover Date.     

Adverse health effects in workers exposed to trace/toxic metals at workplace

Widespread use of metals in industrial activities has enhanced the occupational exposure to toxic metals as well as the health risks of metal hazards to humans. Elemental analysis in human tissues is the most common application of biological monitoring for screening, diagnosis and assessment of such exposures and risk. Among various biopsy materials, blood, hair, nail, teeth and body fluids may be used as bioindicators for this purpose. The present paper deals with the determination of Pb, Cr, Ni, Mn, Fe, Cu and Zn elemental concentration in workers exposed to these metals at workplace by atomic absorption spectrophotometry, with adequate quality control measures using hair as biopsy material. The study group includes the male workers such as welders, foundry man, fitter, hammer man, machine man, cupola man etc., besides office workers of locomotive workshop in Ajmer and surrounding areas exposed to different metals. Age and sex matched controls of persons working in the same area of work in offices etc. and not exposed to metal pollution were selected for valid comparison. It is proposed to validate the use of hair as a biological marker for assessing metal body burden of workers. In our study significant correlations have been found between skin disease and Cr, Mn, Fe, Cu; chest pain and Pb; hypertension and Cu, Mn; mental stress and Mn, Ni, Cu, Zn; liver problem and Ni; indigestion and Cr; Ni, diabetes and Cr, Mn, Ni; tuberculosis and Zn; breathing trouble and Cr, Mn, Fe, Ni, Zn. The advantages of choosing hair as a biopsy material are also given.