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1.
Estimation of essential and toxic element intakes is crucial to evaluate the risks of deficiency or toxicity. The purpose of this study was to investigate and also to compare the dietary intakes of zinc (Zn) and copper (Cu) by adults living in Shiraz, Iran, determined by two procedures: duplicate portion sampling of 21 hospital meals combined with either instrumental analysis (voltammetric measurement) or the use of food composition tables (FCTs). The level of exposure to lead (Pb) and cadmium (Cd) was evaluated as well. The daily Zn intakes of both methods were not significantly different and were higher than the RDA values except the value measured by the instrumental analysis which was lower than the RDA established for a male adult. Daily intake of Cu determined by instrumental analysis was significantly lower and closer to RDA for adults compared with the value estimated by FCTs. The dietary intakes of Pb and Cd were 313 and 61 % of the respective provisional tolerable weekly intakes (PTWIs), respectively. The accuracy of two methods used for estimation of Zn intake was similar. In the case of Cu, the use of FCTs, in which the influence of environmental conditions and dietary habits of meal preparation is not taken into account, overestimated dietary intake. The risk of zinc deficiency was found in adult males. Moreover, the estimated intake of Pb, but not Cd, could be a cause of concern for Shiraz population. Thus, conducting regular periodic studies to assess the dietary intake of mentioned elements are recommended.  相似文献   

2.
北京灰霾天气PM10中微量元素的分布特征   总被引:5,自引:1,他引:4       下载免费PDF全文
采用电感耦合等离子体质谱法(ICP-MS)对北京市2008年4月和5月不同采样点采集的灰霾天PM10样品中的15种微量元素进行了分析,得出了Ti、Fe、Zn、Sn、Pb为全样样品中相对含量较高元素;Ti、Mn、Ni、Cu、Zn、Pb是水溶样样品中相对含量较高元素。与晴天相比,灰霾天样品中微量元素可溶性增强,对人体危害更严重。与2002年分析数据进行对比,因2002年缺少Cr、Cd元素的测试值,全样样品中除了Co、Ni、Cu、Mo元素外,其余测试元素的浓度均有不同程度的升高,Fe和Sn元素的增幅最大。水溶样品中,参与对比元素的含量均下降。文中对含量相对较高的Cr、Mn、Fe、Cu、Zn、Cd、Sn和Pb元素进行了源解析,分析得出采样点附近的交通源及地面扬尘是这些元素的主要来源。  相似文献   

3.
There is a growing concern over the potential accumulation of trace element concentration in groundwater of coastal aquifer owing seawater encroachment in the last several decades. A total of 29 groundwater samples collected from Pesarlanka Island, Krishna delta, Andhra Pradesh, India were analyzed for 13 trace elements (B, V, Mn, Fe, Ni, Co, Cu, Zn, As, Sr, Cd, Ba, and Pb) using inductively coupled plasma mass spectrometry. The results reveal that B, Fe, Ni, As, Sr, and Pb vary from 11.22 to 710.2, 1.25 to 684.6, 0.02 to 37.33, 27.8 to 282.3, 164.1 to 7,009, and 1.97 to 164.4 μg/l, respectively. Ba, Cd, Co, Cu, Ni, V, and Zn are almost within permissible limits for drinking water, but As, Fe, Mn, Pb, B, and Sr are above the permissible limit. The toxic element Pb is 1.64 times more than the maximum permissible limits of drinking water. The minimum value of As is also 2.78 times more, whereas the maximum is 28.2 times the permissible limit. The spatial distributions of alkaline earths (Sr, Ba), transition metals (V, Co, Ni, Fe), metallic elements (Cu, Pb), and (As) were found in considerable variation in the entire Island. Good cross-correlations were found between As, B, Co, and Sr with total dissolved solids and among other trace elements such as B, As, Co, and Sr. The variability observed within the groundwater samples is closely connected to the sea spray input; hence, it is primarily a consequence of geographical and meteorological factors, such as distance from the ocean and time of year. The trace element levels, in particular those of heavy metals, are very low, suggesting an origin from natural sources rather than from anthropogenic contamination. A few trace elements (Sr and B) are found as sensitive parameters responding to changes in fresh to saline groundwater environment. The highly elevated trace elements in this area which may be attributed to marine sediments or death and decay of plants are presented in this paper.  相似文献   

4.
The major and trace element component of 48 recent sediment samples in three distinct intervals (0–10, 10–20, and 20–30 cm) from Lake Ac?göl is described to present the current contamination levels and grift structure of detrital and evaporate mineral patterns of these sediments in this extreme saline environment. The spatial and vertical concentrations of major oxides were not uniform in the each subsurface interval. However, similar spatial distribution patterns were observed for some major element couples, due mainly to the detrital and evaporate origin of these elements. A sequential extraction procedure including five distinct steps was also performed to determine the different bonds of trace elements in the <?60-μ particulate size of recent sediments. Eleven trace elements (Ni, Fe, Cd, Pb, Cu, Zn, As, Co, Cr, Al and Mn) in nine surface and subsurface sediment samples were analyzed with chemical partitioning procedures to determine the trace element percentage loads in these different sequential extraction phases. The obtained accuracy values via comparison of the bulk trace metal loads with the total loads of five extraction steps were satisfying for the Ni, Fe, Cd, Zn, and Co. While, bulk analysis results of the Cu, Ni, and V elements have good correlation with total organic matter, organic fraction of sequential extraction characterized by Cu, As, Cd, and Pb. Shallow Lake Ac?göl sediment is characteristic with two different redox layer a) oxic upper level sediments, where trace metals are mobilized, b) reduced subsurface level, where the trace metals are precipitated.  相似文献   

5.
The aim of this work is to determine the content of essential and toxic elements in 25 raw propolis samples, when considering pollution agents and geographical and botanical factors. The microwave-assisted digestion was the most reliable and accurate method for determination of inorganic elements in propolis samples. The results were obtained using certified reference materials in a good agreement with certified values. Inductively coupled plasma atomic emission spectroscopy was used for the determination of 23 macro- and microelements (Ag, Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Sb, Se, Si, Sn, and Zn). A Mercury analyzer was also utilized for the detection of the total Hg. Among the analyzed metals, Ca, K, Mg, Zn, Si, S, Fe, Al, P, and Na were found to be the most predominant. Heavy metals (As, Cd, Hg, and Pb) were determined in minimal concentration, and Pb was the highest mean contained toxic (<3.80 mg/kg), without influence on provisional tolerable weekly intake values. The method can be applied for routine analysis and quality and environmental pollution controls of toxic elements in propolis samples. The results obtained indicate no pollution of the collection areas and naturally high concentration of Al (460?±?62.2 mg/kg).  相似文献   

6.
This study proposes a practical method to estimate elemental composition and distribution in order to attribute source and quantify impacts of aerosol particles at an urban region in Kolkata, India. Twelve-hour total particulates were collected in winter (2005–2006) and analyzed by energy-dispersive X-ray fluorescence technique to determine multi-elemental composition, especially trace metals. The aerosols consist of various elements including K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, and Pb which exhibit significant concentration at various sites (p?<?0.05). The concentration of different metallic elements were found in the order of Zn ?> ?Pb ?> ?Ni ?> ?Cu ?> ?Cr ?>? Co. Statistical multivariate analysis and correlation matrix analyses were performed for factor identification and consequent source apportionment. Contour profiles demonstrate spatial variation of elemental compositions indicating possible source contribution along with meteorological influences. Spatial differences were clearly most significant for Zn, Ni, Pb, and Cu reflecting the importance of anthropogenic inputs, primarily from automobile sources.  相似文献   

7.
Concentrations of trace elements (Cd, Cu, Ni, Pb, V, and Zn) were determined in the soft tissues (adductor muscle and gills) of the pearl oyster Pinctada radiata and surficial sediments from two sampling sites located in the northern part of the Persian Gulf by Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS). Moreover, the levels of Li, Mg, Al, Mn, Fe, Cu, Sr, Ba, Pb, and Zn were measured in two shell layers (prismatic and nacreous) using Laser Ablation Inductively Coupled Plasma Mass Spectrometer (LA-ICP-MS). There were significant differences between the sampling sites with regard to mean concentrations of Cu, Mn, and Al in the prismatic layers of the shells. But in terms of the soft tissues, only in the case of Ni accumulation in the muscle significant differences between the sites could be observed. No significant differences could be found between the sites from the elements concentrations in the sediments point of view. The levels of Cd, Cu, Ni, and Zn in the gills were markedly higher than those in the muscle. Concentrations of Mn, Mg, Li, and Cu in the prismatic layer were significantly higher than in the nacreous but the reverse case could be found for Sr. The patterns of metal occurrence in the selected tissues, shell layers, and sediments exhibited the following descending order: Zn, Ni?>?Cd, Cu?>?V, and Pb and Zn, Ni, Cd?>?Cu, V, and Pb for muscle and gills, respectively; Zn?>?Cu, Ni, Pb, Cd, and V for sediments; Mg?>?Sr, Mn, Li, Al, Fe, Ba, Cu, Pb, and Zn for the prismatic layer; and Sr, Mg?>?Mn, Al, Fe, Li, Ba, Cu, Pb, and Zn for the nacreous layer. In most cases, the temporal variations of the elements levels in the prismatic layer were clearer than those in the nacreous layer (especially for Li, Mg, Mn, Pb, and Fe). Comparison of the gained data from this study with the other relevant researches shows that in most cases the levels of the elements in this investigation either fell within the range for other world areas or were lower. Generally, it can be concluded that the shell (especially prismatic layer) of P. radiata can be considered as a suitable proxy for temporal and spatial variations of the trace elements (and probably some environmental parameters) in the study area.  相似文献   

8.
Spanish gluten-free rice, cereals with gluten, and pureed baby foods were analysed for essential macro-elements (Ca and Na), essential trace elements (Fe, Cu, Zn, Mn, Se, Cr, Co and Ni) and non-essential trace elements (As, Pb, Cd and Hg) using ICP-MS and AAS. Baby cereals were an excellent source of most of the essential elements (Ca, Fe, Cu, Mn and Zn). Sodium content was high in pureed foods to improve their flavour; fish products were also rich in Se. USA pure baby rice samples had the highest contents of all studied essential elements, showing a different nutrient pattern compared to those of other countries. Mineral fortification was not always properly stated in the labelling of infant foods. Complementary infant foods may also contain significant amounts of contaminants. The contents of Hg and Cd were low enough to guarantee the safety of these infant foods. However, it will be necessary to identify the source and reduce the levels of Pb, Cr and As in Spanish foods. Pure baby rice samples contained too much: Pb in Spain; As in UK; As, Cr and Ni in USA; and Cr and Cd in China.  相似文献   

9.
Airborne particulate trace metals have important health implications. As a consequence, their concentrations are increasingly monitored in many urban locations worldwide. In this study, fine atmospheric particles (PM(2.5)) were collected in Singapore over a period of 83 consecutive days during 2000, and analysed to determine the concentration of trace elements using ICP-MS. Altogether, eighteen airborne trace metals were quantified: Al, Ag, Ba, Cd, Cr, Co, Cu, Fe, Ga, Li, Mn, Ni, Pb, Sr, Zn, V, Si, and Ti. While Li was the least abundant trace metal with a mean concentration of 0.2 ng m(-3), Zn showed the maximum mean concentration of 279.1 ng m(-3). Calculation of enrichment factors indicated that the elements Pb, Zn, Cd, V, Ni, Cr, and Cu were enriched by factors of 30 to 5000 relative to their natural abundance in crustal soil. The extent of metal pollution in the study area was assessed by comparing the measured concentrations to those reported in the literature for a selected number of urban sites in other parts of the world. Factor analysis was used to identify the major sources affecting particulate air pollution in Singapore. The sources that contribute to the loading of trace metal-bearing aerosols in the Singapore urban atmosphere include fuel oil-fired power plants, metal processing industry, land reclamation and construction activities, municipal solid waste incinerators, and traffic emissions.  相似文献   

10.
Coastal and estuarine areas are often polluted by heavy metals that result from industrial production and agricultural activities. In this study, we investigated the concentration trait and vertical pattern of trace elements, such as As, Cd, Ni, Zn, Pb, Cu, and Cr, and the relationship between those trace elements and the soil properties in coastal wetlands using 28 profiles that were surveyed across the Diaokouhe Nature Reserve (DKHNR). The goal of this study is to investigate profile distribution characteristics of heavy metals in different wetland types and their variations with the soil depth to assess heavy metal pollution using pollution indices and to identify the pollution sources using multivariate analysis and sediment quality guidelines. Principal component analysis, cluster analysis, and pollution level indices were applied to evaluate the contamination conditions due to wetland degradation. The findings indicated that the concentration of trace elements decreased with the soil depth, while Cd increases with soil depth. The As concentrations in reed swamps and Suaeda heteroptera surface layers were slightly higher than those in other land use types. All six heavy metals, i.e., Ni, Cu, As, Zn, Cr, and Pb, were strongly associated with PC1 (positive loading) and could reflect the contribution of natural geological sources of metals into the coastal sediments. PC2 is highly associated with Cd and could represent anthropogenic sources of metal pollution. Most of the heavy metals exhibited significant positive correlations with total concentrations; however, no significant correlations were observed between them and the soil salt and soil organic carbon. Soil organic carbon exhibited a positive linear relationship with Cu, Pb, and Zn in the first soil layer (0–20 cm); As, Cr, Cu, Ni, Pb, and Zn in the second layer (20–40 cm); and As, Cr, Cu, Ni, Pb, and Zn in the third layer (40–60 cm). Soil organic carbon exhibited only a negative correlation with Cd (P?I geo values), which averaged less than 0 in the three soil layers, this finding indicates that the soils have remained unpolluted by these heavy metals. The mean concentrations of these trace elements were lower than Class I criteria. The degradation wetland restoration suggestions have also been provided in such a way as to restore the reserved flow path of the Yellow River. The results that are associated with trace element contamination would be helpful in providing scientific directions to restore wetlands across the world.  相似文献   

11.
The levels of trace elements (As, Cd, Cr, Cu, Fe, Ni, Pb, Se, and Zn) in eight species of cultured freshwater fishes from Jiangxi province were determined by inductively coupled plasma-mass spectroscopy. All the studied trace element levels in fish muscles from Jiangxi province did not exceed Chinese national standard and European Union standard, and they were often lower than previous studies. The calculated target hazard quotient values for all the studied trace elements in fish samples were much less than 1, suggesting that the studied trace elements in fish muscles from Jiangxi province had not pose obvious health hazards to consumers. As and Cd concentrations in northern snakehead were much higher than that in other fishes, demonstrating that this fish species could be valuable as a bioindicator of As and Cd in environmental surveys. In addition, the highest concentrations of Fe, Zn, and moderate contents of other essential trace elements in crucian carp indicated that crucian carp could be a good nutrient source of essential trace elements for human health.  相似文献   

12.
In this paper, we surveyed the concentration of nine trace elements (As, Cd, Cu, Fe, Mn, Ni, Pb, Tl and Zn) in bermudagrass (Cynodon dactylon) 3 years after the mine spill in Aznalcóllar (south Spain). The results were compared with those that had been obtained for the same species in a previous study, 18 months after the accident. Three types of soil condition were determined: i) unaffected soils (UN, control); ii) cleaned up and amended soils (A, amended); and (iii) non-amended soils, inaccessible to the clean-up and remediation operations (NA, non-amended). The trace element concentrations in the plants were lower than those reported in the first sampling for both washed (plant tissues) and unwashed plants (as consumed by herbivores). Apart from Cd, trace elements concentrations (plant tissues) were similar in the A and the UN soils. In the NA soils, the Cd, Fe, Mn, Zn and Pb levels in unwashed plants were excessive for animal consumption. This wild grass seems to be suitable as a soil stabilizer for spill affected soils and as a biomonitor for soil pollution by some trace elements (As, Cu and Zn); however, its potential for phytoextraction is negligible.  相似文献   

13.
The sediment in Dianchi Lake, a hypereutrophic plateau lake in southwest China, was investigated and the concentration of heavy metals (Cu, Cr, Ni, Zn, Pb, Fe, Mn, and Cd) in the sediment and sediment properties were determined. Their spatial distribution and sources were analyzed using multivariate statistics. The result indicated that the studied metals exhibited three distinct spatial patterns; that is, Cu, Pb, Zn, and Ni had a similar distribution, with a concentration gradient from the north to the south part of the lake; Cd and Cr presented a similar distribution; Fe and Mn presented a quite different distribution than other metals, which indicated their different sources and geochemistry processes. Correlation and cluster analysis (CA) provided origin information on these metals and the CA result was observed corresponding to those three spatial patterns. Principal component analysis further displayed metal source and driving factors; that is, Cu, Pb, Zn, Ni, Cd, and Cr were mainly derived from anthropogenic sources, and Fe and Mn were mainly the result of natural processes. Sediment assessment was conducted using geoaccumulation index (Igeo), potential ecological risk indices, and USEPA guidelines. The result indicated that, generally, Cd was the most serious risk metal; Pb and Cu posed moderate potential ecological risk; Cr, Zn, and Ni had slight ecological risk; Fe and Mn had little risk. Comparison of the assessment tools showed that each of the methods had its limitation and could bias the result, and the combined use of the methodologies and local knowledge on lithology or metal background value of soil in the practice would give a more comprehensive understanding of the metal risk or pollution. Statistical analysis also indicated that nutrients had different impacts on Fe, Mn, and trace elements, which implied that in the assessment of metal risk, nutrients impact should be taken into consideration especially for eutrophic waters.  相似文献   

14.
Extensive aquatic or semi-aquatic production of water spinach (Ipomoea aquatica Forssk.) for human consumption takes place in Southeast Asia. The aim of this study was to assess the concentrations of 38 elements in soil and water spinach cultivated under different degrees of wastewater exposure in Hanoi, Vietnam. The results showed no effect of wastewater use on the overall element concentrations in soil and water spinach. Mean soil concentrations for selected potentially toxic elements at the studied field sites had the following ranges 9.11–18.7 As, 0.333–0.667 Cd, 10.8–14.5 Co, 68–122 Cr, 34.0–62.1 Cu, 29.9–52.8 Ni, 32.5–67.4 Pb, 0.578–0.765 Tl and 99–189 Zn mg kg−1 dry weight (d.w.). In all samples Cd, Pb and Zn soil concentrations were below the Vietnamese Guideline Values (TCVN 7209-2002) for agricultural soils whereas As and Cu exceeded the guideline values. Maximum site element concentrations in water spinach were 0.139 As, 0.032 Cd, 0.135 Cr, 2.01 Cu, 39.1 Fe, 57.3 Mn, 0.16 Ni, 0.189 Pb and 6.01 Zn mg kg−1 fresh weight (f.w.). The site and soil content of organic carbon were found to have high influence on the water spinach element concentrations whereas soil pH and the total soil element concentrations were of less importance. The estimated average daily intake of As, Cd, Cu, Fe, Pb and Zn for adult Vietnamese consumers amounts to <11% of the maximum tolerable intake proposed by FAO/WHO for each element. It is assessed that the occurrence of the investigated elements in water spinach will pose low health risk for the consumers.  相似文献   

15.
Manchar Lake is the largest natural freshwater lake in Pakistan. The Lake has received less fresh water in past few years. In addition, drainage water is being discharged in the Lake through Main Nara Valley Drain (MNVD) since many years. Consequently, concern has grown regarding the water quality of the Lake. The aim of this study was to assess the water quality of Manchar Lake and MNVD and the objectives were to determine physiochemical properties and the concentrations of common cations and anions as well as seven trace metals i.e. Cu, Ni, Zn, Co, Fe, Pb and Cd. The concentration of the trace metals were determined by simultaneous preconcentration and solvent extraction using flame atomic absorption spectrometer. Results of physicochemical parameters of Manchar Lake water samples showed mean pH 8.4 (±0.2), conductivity 2,310.3 (±581.3) μS cm−1 and hardness (as CaCO3) 213.1 (±62.3) mg l−1. Mean concentrations of cations and anions were Na 521.5 (±49.7), Cl 413.6 (±225.7), Ca 70.7 (±12.9), Mg 56.2 (±28.9), K 17.6 (±6.5), 0.34 (±0.2) and 0.02 (±0.01) mg l−1. Mean concentrations of trace metals were Zn 15.7 (±1), Fe 12 (±3.5), Pb 9 (±2.7), Cu 8.9 (±7.7), Ni 4.3 (±3.4), Co 4 (±3.4) and Cd 1.1 (±1) μg l−1. MNVD water samples showed mean pH 8.9 (±0.8), conductivity 1,735.7 (±567.8) μS cm−1 and hardness (as CaCO3) 184.8 (±32.4) mg l−1. In MNWD, the mean concentrations of cations and anions were Na 482.7 (±11.7), Cl 395.7 (±271.5), Ca 79.1 (±23.5), Mg 54.2 (±28.1), K 26.2 (±21.3), NO−3 0.5 (±0.3) and 0.1 (±0.1) mg l−1. Mean concentrations of trace metals observed in MNWD water were Fe 14.9(±3.5), Cd 8.3 (±9.4), Pb 6.9 (±2.4), Cu 6.6 (±3.1), Zn 6.2 (±1.8), Co 4.5 (±2.7), and Ni 3.5 (±2.9) μg l−1. The pH of both Manchar Lake and MNVD waters and concentration of Pb in Manchar Lake and concentration of Cd in MNVD water were higher than the World Health Organisation’s guideline values for the drinking water quality. The water quality of Manchar Lake was found degraded.  相似文献   

16.
Study of trace elements in wet atmospheric precipitation in Tehran,Iran   总被引:1,自引:0,他引:1  
In this study, measurements of the trace metals Zn, Cd, Cr, Ni, Pb, Cu, Fe and Al were performed on 53 wet atmospheric precipitation samples (snow and rainwater) collected at a central site of Tehran. Samples were collected using a bulk sampler equipped with a high-density polyethylene funnel from November to May in 2011 and 2012 on the roof of a building in the city centre. Trace metals in the filtered samples were measured with ICP-MS. Statistical analysis of the results revealed that Al, which is principally a crustal-derived element, was the highest mean measured concentration. The pH ranged from 4.2 to 7.1 with a mean value of 5.1. Crustal enrichment factors (EFc) related to the relative abundance of elements in crustal material was calculated using Al as reference crustal. EFc calculations indicated that samples were not enriched with Fe and Cr but were, fairly to extremely, enriched with Zn, Cd, Ni, Pb and Cu. Factor component analysis with varimax-normalized rotation was conducted to find the probable sources of the measured species. This resulted in two factors with eigenvalues greater than unity. Factor 1 showed an anthropogenic source, mostly industrial combustion and local traffic emissions, for Zn, Cd, Ni, Pb, and Cu while factor 2 showed a crustal contribution for Al, Fe and Cr.  相似文献   

17.
The content of nutrients (N, P, K, Ca and Mg) and of trace metals (Fe, Cu, Mn, Zn, Pb, Cd, Co and Ni) in water, bottom sediments and various organs of Glyceria maxima from 19 study sites selected in the Jeziorka River was determined. In general, the concentrations of nutrients recorded in the plant material decreased in the following order: leaf>root>rhizome>stem, while the concentrations of the trace elements showed the following accumulation scheme: root>rhizome>leaf>stem. The bioaccumulation and transfer factors for nutrients were significantly higher than for trace metals. G. maxima from agricultural fields was characterised by the highest P and K concentrations in leaves, and plants from forested land contained high Zn and Ni amounts. However, the manna grass from small localities showed high accumulation of Ca, Mg and Mn. Positive significant correlations between Fe, Cu, Zn, Cd, Co and Ni concentrations in water or sediments and their concentrations in plant indicate that G. maxima may be employed as a biomonitor of trace element contamination. Moreover, a high degree of similarity was noted between self-organizing feature map (SOFM)-grouped sites of comparable quantities of elements in the water and sediments and sites where G. maxima had a corresponding content of the same elements in its leaves. Therefore, SOFM could be recommended in analysing ecological conditions of the environment from the perspective of nutrients and trace element content in different plant species and their surroundings.  相似文献   

18.
In this study, the levels of natural and anthropogenic metal contamination (aluminum (Al), iron (Fe), manganese (Mn), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn)) in surface sediments of three harbors along the Iranian coast of Gulf of Oman were examined and reported for the first time. Effect of grain size, mineralogy, normalization technique using Fe concentrations, and different sediment quality guidelines were discussed. Data from the harbors were compared with other harbors worldwide. Sediments inside the harbors are characterized by moderate and high levels of pollution by trace metals Cu (12–287 μg/g), Pb (11–1,780 μg/g), Zn (38–547 μg/g), Cr (70–2,370 μg/g), and Ni (31–116 μg/g). However, As and Cd did not show considerable pollution inside and outside the harbors. Considering that there is no industrial activity around the study harbors, the major sources of contamination in the harbors are repairing, fueling, greasing, and painting of fishing ships and boats. Mineralogy of sediments in the study area as well as trace metal concentration in reference samples taken from onshore geological units confirmed that natural inputs of Cd, Cu, Pb, and Zn in the harbors are very low while most of Ni and Cr contamination in the study area comes from erosion of ophiolitic mélange units at the North of Makran mountains.  相似文献   

19.
Multi-elemental profiles in bark of green ash trees collected in three representative areas of Buenos Aires, Argentina and Montevideo, Uruguay, were assessed as potential air pollution indicators. Ten elements: Al, Ba, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn, were measured using inductively coupled plasma optical emissions spectrometry from 70 samples collected in different environments: central, residential and rural (reference site), in order to compare spatial patterns of metal concentration. The samples used as a control were collected from a nature reserve situated far away from any significant influences, not even a nearby road. The reference site (RF) exhibited the lowest concentrations of Al, Cr, Fe, Ni, Pb, and Zn. However, Ba and Mn showed similar concentrations in all measured sites. Magnesium is the only element that had a greater concentration in RF than at the other sites. Copper did not show any clear pattern. The Centre of Montevideo (MVD) showed higher concentrations of Al, Ba, Cr, Fe, Pb and Zn than the Centre of Buenos Aires (BA). In the A sectors, Montevideo (SAMVD) showed higher concentrations of Al, Cu, Mg, Ni, and Zn and lower concentrations of Ba, Cr, Fe, Mn, and Pb than Buenos Aires (SABA). In the B sectors, Montevideo (SBMVD) showed higher concentrations of Al, Ba, Cu, Fe, Pb, and Zn and lower concentrations of Cr and Mg than Buenos Aires (SBBA), but similar concentrations of Mn and Ni. The use of bark for biomonitoring metals allowed us to detect concentration differences related to the urban fabric and the different kinds of vehicles and their fuels. In the cities, the differences in metal concentrations detected in bark were more striking between the sectors than between centers, despite CBA being much larger than CMVD in population, extension and vehicular traffic.  相似文献   

20.
Concentrations of arsenic and four additional trace elements (Cu, Cr, Ni, and Zn) were determined by inductively coupled plasma–optical emission spectrometry in the muscular tissue of the yellow catfish (Cathorops spixii) and the urutu catfish (Genidens genidens) from Paranaguá Estuarine Complex, Brazil (PEC). The PEC can be characterized by an environment of high ecological and economic importance in which preserved areas of rainforest and mangroves coexist with urban activities as ports and industries. The average concentrations (in milligram per kilogram dry weight) of elements in the muscle tissue of C. spixii are as follows: Zn (31), As (17), Cu (1.17), Cr (0.62), and Ni (0.28). Similar concentrations could be found in G. genidens with exception of As: Zn (36), As (4.78), Cu (1.14), Cr (0.51), and Ni (0.14). Fish from the geographic northern rural region (Guaraqueçaba–Benito) display higher As concentrations in the muscle tissues than fish found in the south-western (urban) part of the PEC. An international comparison of muscle tissue concentrations of trace elements in fish was made. Except for Ni in C. spixii, a tendency of decrease in element concentration with increasing size (age) of the fish could be observed. According to the National Health Surveillance Agency of Brazil, levels of Cr and As exceeded the permissible limits for seafood. An estimation of the provisional tolerable weekly intake of As was calculated with 109 % for C. spixii and with 29 % for G. genidens.  相似文献   

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