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1.
Heavy metals in honey are of interest not only for quality control, but also for determination environmental contamination. The objective of this work was to determine distribution of the levels of selected heavy metals. Levels of copper (Cu), cadmium (Cd), manganese (Mn), Iron (Fe), magnesium (Mg) and nickel (Ni) in honey samples (21) in Kahramanmaraş region were determined by atomic absorption spectrometer (AAS). The mean values for Cu, Cd, Mn, Fe, and Mg were 0.01, 0.32, 0.03, 0.36 and 10.45 ppm, respectively. Nickel was not detected in honey samples. Kahramanmaraş honey samples were not free of heavy metals but the levels of them were found well below the permitted levels. The results suggested that honey may be useful for assessing the presence of environmental contaminants.  相似文献   

2.
From 1977–1978 to 1990, concentrations of polychlorinated biphenyls (PCBs) and most organochlorine pesticides declined in eggs of red-breasted mergansers (Mergus serrator) nesting on islands in northwestern Lake Michigan. Total PCBs decreased 60% (from 21 ppm in 1977–1978 to 8.5 ppm in 1990) and p,p-DDE decreased 66% (from 6.5 to 2.2 ppm). Dieldrin decreased only 16% (from 0.82 to 0.69 ppm). In 1990, 79.1% of incubated eggs hatched, which was not significantly different from the 83.5% that hatched in 1977–1978.The U.S. Government right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged.  相似文献   

3.
The concentrations of cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc in water and bed sediments of river Gomti have been studied in a fairly long stretch of 500 km from Neemsar to Jaunpur. Grab samples of water (October 2002–March 2003) and bed sediments (December 2002 and March 2003) were collected from 10 different locations following the standard methods. The river water and sediment samples were processed and analyzed for heavy metals viz., Cd, Cr, Cu, Fe, Pb, Mn, Ni, and Zn, and using ICP-AES. The heavy metals found in the river water were in the range: Cd (0.0001–0.0005 mg/L); Cr (0.0015–0.0688 mg/L); Cu (0.0013–0.0.0043 mg/L); Fe (0.0791–0.3190 mg/L); Mn (0.0038–0.0.0973 mg/L); Ni (0.0066–0.011 mg/L); Pb (0.0158–0.0276 mg/L); and Zn (0.0144–0.0298 mg/L) respectively. In the sediments the same were found in the range: Cd (0.70–7.90 g/g); Cr (6.105–20.595 g/g); Cu (3.735–35.68 g/g); Fe (5051.485–8291.485 g/g); Mn (134.915–320.45 g/g); Ni (13.905–37.370 g/g); Pb (21.25–92.15 g/g); and Zn (15.72–99.35 g/g) of dry weight respectively. Some physico-chemical parameters viz., pH, total solids, total dissolved solids, total suspended solids, dissolved oxygen, biological oxygen demand, chemical oxygen demand, hardness etc. were estimated as these have direct or indirect influence on the incidence, transport and speciation of the heavy metals. Based on the geoaccumulation indices, the Gomti river sediments from Neemsar to Jaunpur are considered to be unpolluted with respect to Cr, Cu, Fe, Mn, and Zn. It is unpolluted to moderately polluted with Pb. In case of Cd it varies from moderately polluted to highly polluted. As far as Ni is concerned the sediment is very highly polluted at Barabanki and Jaunpur D/s. No correlation was found between enrichment factor and geoaccumulation index.  相似文献   

4.
The aim of this study was to analyse the relationship between the distribution of hay-fever patients in the city of Córdoba, south-western Iberian Peninsula, and the specific atmospheric biological content originating from local sources. Four different districts were established in the metropolitan area of the city, according to vegetational and urbanistic characteristics. Air samples were taken in each area using portable Hirst-type samplers (Lanzoni VPPS 1000) and the spectrum of biological content was defined. Patients attending the Allergy Unit at Córdoba Teaching Hospital in 2000 with allergic rhinitis and/or asthma, and displaying a positive reaction to aeroallergen extracts, were distributed within the areas as a function of their district of residence. Aerobiological results revealed differences in pollen content between areas, in terms of both quantity and number of pollen types recorded. These differences were largely due to proximity to rural areas, prevalence of pollen from typically urban species and the possible effect of urban architecture as a barrier to the dispersal/ concentration of particles and other pollutants. Patients were not uniformly distributed within the city. The majority lived in districts in which pollen from rural species was mixed with pollen from ornamentals. Patients living in typically urban districts displayed a higher prevalence of allergy to pollen from ornamentals. It is concluded that a high degree of exposure to the same environment may influence the development of sensitisation to the particular pollen load associated with that area.  相似文献   

5.
The ocelot (Felis pardalis) isan endangered neotropical cat distributed within asmall range in the Lower Rio Grande Valley (LRGV), inTexas, U.S.A. Studies of the impacts of environmentalcontaminants in wild cats are few. Approximately onefourth of the estimated population (about 100) ofocelots in the LRGV was sampled to evaluate theimpacts of chlorinated pesticides, polychlorinatedbiphenyls, and trace elements on the population. Hairwas collected from 32 ocelots trapped between 1986–1992,and blood was collected from 20 ocelots trappedbetween 1993–1997. A few blood samples were obtainedfrom individuals recaptured two or three times. Tissue samples from 4 road-killed ocelots were alsoanalyzed. DDE, PCBs, and Hg were some of the mostcommon contaminants detected in hair and blood. MeanHg levels in hair ranged from 0.5 to 1.25 g g-1 dw,Se from 1.5 to 3.48 g g-1 dw, and Pb from 0.56 to26.8 g g-1 dw. Mean DDE concentrations in plasma ranged from 0.005 g g-1 ww to 0.153 g g-1 ww, and PCBs ranged from 0.006 g g-1 ww to 0.092 g g-1 ww. Mean Hg levels in red blood cells rangedfrom 0.056 g g-1 dw to 0.25 g g-1 dw. Concentrations of DDE, PCBs, or Hg, did not increasesignificantly with age, although the highestconcentrations of DDE and Hg were found in olderanimals. Overall, concentrations of DDE, PCBs, and Hgwere low and at levels that currently do not pose anythreat to health or survival of the ocelot. This isfurther supported by good reproduction of the ocelotin the LRGV, where adult females averaged about 1.5kittens/litter. Thus, it seems that the current majorthreat to recovery of the ocelot in the LRGV may behabitat loss, although potential impacts of newgeneration pesticides, such as organophosphorus andcarbamate insecticides need further study.  相似文献   

6.
Noise mapping has been used as an instrument for assessment of environmental noise, helping to support decision making on urban planning. In Brazil, urban noise is not yet recognized as a major environmental problem by the government. Besides, cities that have databases to drive acoustic simulations, making use of advanced noise mapping systems, are rare. This study sought an alternative method of noise mapping through the use of geoprocessing, which is feasible for the Brazilian reality and for other developing countries. The area chosen for the study was the central zone of the city of Sorocaba, located in São Paulo State, Brazil. The proposed method was effective in the spatial evaluation of equivalent sound pressure level. The results showed an urban area with high noise levels that exceed the legal standard, posing a threat to the welfare of the population.  相似文献   

7.
Research on the influence of the activities of Pechenganickel Mining and Metallurgical Company on sediment heavy-metal geochemistry of the subarctic Lake Kuetsj?rvi (north-western Russia) are described. It is estimated that during 60 years of mining/refining activity, 310 t of Ni, 120 t of Cu, 14 t of Co, 19 t of Zn, 0.087 t of Cd, 0.78 t of Pb and 0.053 t of Hg have accumulated in the lake sediments. The latter can be a source of secondary pollution and represent a danger for the lake ecosystem. The sedimentation rate in the lake is estimated to be within the range of 1.5-3 mm year(-1). The average concentrations of Ni, Cu, Hg and Co in superficial sediments have increased 25, 14, 11 and 5 times, respectively in the last century.  相似文献   

8.
This study was designed to evaluate the degree of environmental contamination and possible exposure of pregnant women to toxic elements in seven selected areas of S?o Paulo State, Brazil. The overall median concentration of Mo in maternal blood was 0.53 μg L?1, highly significant differences found between sites (p < 0.0001). Cd was found to be low overall - 0.09 μg L?1 (0.01-0.58 μg L?1) - with mothers from the Coastal and Rural 1 sites having the highest levels (p < 0.016).Median Hg concentration was 0.60 μg L?1 (0.06 μg L?1-4.35 μg L?1); median Pb level was 16.2 μg L?1 (3.5-57.7 μg L?1) and no differences between sites were observed for both metals. Median Mn level was 16.7 μg L?1 (7.0-39.7 μg L?1), being highest in Urban 2 site (p < 0.016). Concentrations of maternal Co were found to range between 0.06 μg L?1 and 1.1 μg L?1 (median 0.25 μg L?1) and As level was 0.60 μg L?1 (0.10-3.8 μg L?1) overall, with no statistical significance between sites for Co and As. Median Se concentrations were found to be 64 μg L?1 (36-233 μg L?1), with the highest median levels found in Urban 3 site; site differences were statistically significant (p < 0.0001). Correlation for each element (between paired maternal and cord blood) was measured only in Rural site 1; significant correlation was shown for Hg, Pb, Mn and Co (p < 0.05). These findings may be interpreted as indicating low environmental contamination in S?o Paulo State, Brazil. These findings could also indicate that pregnant women have little or no contact with pollutants, possibly due to awareness campaigns carried out by public health practitioners.  相似文献   

9.
Concentration of the some heavy metals (Co, Cu, Fe, Ni, Pb and Zn) Mediterranean mussel Mytilus galloprovincialis from Yalova (Marmara Sea) were investigated seasonally. The mean concentrations of Co, Cu, Fe, Ni, Pb and Zn in the soft tissues were 4.08 ± 0.67, 5.54 ± 0.59, 156.72 ± 20.18, 3.71 ± 1.14, 2.92 ± 0.51 and 106.23 ± 5.66 mg kg(?-1) dry weights, respectively. There were no significant differences between the metal concentrations among the seasons (P > 0.05). The mean Pb and Zn concentrations were higher than the acceptable limit proposed by International Turkish standards.  相似文献   

10.
Health Impact Assessment (HIA) is a decision support approach which is applied in various shapes and forms throughout the world. In England, amongst a range of areas of application, HIA is applied in local (spatial) plan making and project development planning. Whilst various authors have reflected on HIA practice in England, the extent of application and its quality has remained unclear. This paper aims at addressing this gap by reporting on the results of a systematic review of HIA in planning. It is found that between 100 and 200 HIAs are likely being produced each year in England. Whilst most assessments are rapid (desk based), there are also examples of comprehensive and intermediate HIAs, where a participatory procedural approach is followed. An important finding is that those HIAs applied within the context of other assessments (integrated impact assessment -IIA, strategic environmental assessment - SEA/ sustainability appraisal -SA and environmental impact assessment – EIA) tend to be of a higher quality than standalone HIAs, mainly because of the existing comprehensive statutory procedural requirements for these other assessments into which HIA can be integrated.  相似文献   

11.
The Republican River Basin of Colorado,Nebraska, and Kansas lies in a valley which contains PierreShale as part of its geological substrata. Selenium is anindigenous constituent in the shale and is readily leached intosurrounding groundwater. The Basin is heavily irrigated throughthe pumping of groundwater, some of which is selenium-contaminated, onto fields in agricultural production. Water,sediment, benthic invertebrates, and/or fish were collected from46 sites in the Basin and were analyzed for selenium to determinethe potential for food-chain bioaccumulation, dietary toxicity,and reproductive effects of selenium in biota. Resultingselenium concentrations were compared to published guidelines orbiological effects thresholds. Water from 38% of the sites (n = 18) contained selenium concentrations exceeding 5 g L-1, which is reported to be a high hazard for selenium accumulation into the planktonic food chain. An additional 12 sites (26% of the sites) contained selenium in water between 3–5 g L-1, constituting a moderate hazard. Selenium concentrations in sedimentindicated little to no hazard for selenium accumulation fromsediments into the benthic food chain. Ninety-five percent ofbenthic invertebrates collected exhibited selenium concentrationsexceeding 3 g g-1, a level reported as potentially lethal to fish and birds that consume them. Seventy-five percent of fish collected in 1997, 90% in 1998, and 64% in 1999 exceeded 4 g g-1selenium, indicating a high potential for toxicity andreproductive effects. However, examination of weight profilesof various species of collected individual fish suggestedsuccessful recruitment in spite of selenium concentrations thatexceeded published biological effects thresholds for health andreproductive success. This finding suggested that universalapplication of published guidelines for selenium may beinappropriate or at least may need refinement for systems similarto the Republican River Basin. Additional research is needed todetermine the true impact of selenium on fish and wildliferesources in the Basin.  相似文献   

12.
The chemical speciation, fractionation and availability of mercury in sediments from a cinnabar mining area (Almadén, Spain) was studied with different extraction and analytical procedures, in order to determine the degree to which the ecosystem is harmed by this pollutant. Three total extraction procedures, a sequential extraction and the speciation of organo-mercury compounds were performed in nine sediment samples. In the study area, although concentrations of mercury can be extremely high (up to 1,000 mg kg(-1)), no organomercury compounds were detected (< 2 microg kg(-1) and the availability of this element seems restricted. One of the methods for total extraction presented considerably lower recovery in Almadén's sediments, yet the results were controlled with certified reference materials. This disagreement was attributed to the fact that the mercury is in a refractory form. Sequential extraction was able to show that most of the mercury is associated with sulfides (probably as metacinnabar) or in the residual refractory phase (probably as red cinnabar).  相似文献   

13.
The Yamaska River drainage basin in Quebec, Canada, is intensively farmed and heavily polluted with poorly treated domestic and industrial wastes. We investigated the responses of the resident and colonizing components of the benthic macroinvertebrate community to municipal/industrial versus agricultural pollution in the basin, and evaluated the performances of seven diversity and biotic indices for assessing water quality. Samples of riffle-dwelling, infaunal and colonizing invertebrates were collected from 13 stations representing a wide range of types and degrees of pollution using Surber, scoop and artificial substrate samplers. The data were summarized using the indices S (number of taxa), N (number of individuals), H (Shannon-Wiener's diversity index), D (Simpson's diversity index), BBI (Belgian Biotic Index), TBI (a modification of Hilsenhoff's Biotic Index), % CHIR (percentage of arthropods consisting of Chironomidae) and %OLIGO (percentage of total organisms consisting of Oligochaeta). Different components of the community generated somewhat different assessments and were, therefore, complementary. Community composition, expressed as the percentage of individuals contributed by major taxonomic groups, reflected the kinds of stresses at a station more consistently than did any of the indices. S and TBI came closest to ranking control, agricultural and municipal/industrial sites in accordance with our a priori classification, both between months and among sampling methods. %OLIGO usually separated municipal/industrial sites from control sites. Other indices were found to be less sensitive, accurate or temporally stable, or were otherwise inappropriate for use with certain sampling methods or for certain types of pollution. With most of our samples, all of the summary indices suggested that the impact of agricultural practices on stream ecosystems may be as severe as the impacts of municipal and industrial wastes.  相似文献   

14.
We examined the response of demographic, morphological, and chemical parameters of turtle grass (Thalassia testudinum), to much-higher-than-normal rainfall associated with an El Niño event in the winter of 1997–1998. Up to 20 inches of added rain fell between December 1997 and March 1998, triggering widespread and persistent phytoplankton blooms along the west coast of Florida. Water-column chlorophyll concentrations estimated from serial SeaWiFS imagery were much higher during the El Niño event than in the previous or following years, although the timing and magnitude of phytoplankton blooms varied among sites. Seagrass samples collected in 1997, 1998, and 1999 provided an excellent opportunity to test the responsiveness of Thalassia to decline and subsequent improvement of water quality and clarity in four estuaries. Using a scoring technique based on temporal responsiveness, spatial consistency, and statistical strength of indicators, we found that several morphological parameters (Thalassia shoot density, blade width, blade number, and shoot-specific leaf area) were responsive and consistent measures of light stress. Some morphological parameters, such as rhizome apex density, responded to declines and subsequent improvement in water clarity, but lacked the statistical discriminating power necessary to be useful indicators. However, rhizome sugar, starch, and the total carbohydrate concentrations also exhibited spatially and temporally consistent variation as well as statistical strength. Because changes in shoot density, as well as water clarity, affect rhizome carbohydrate levels, a composite metric based on Thalassia shoot density and rhizome carbohydrate levels together is probably more useful than either parameter alone as an indicator of seagrass health.  相似文献   

15.
Zeuss?CKoutine aquifer, located in southeastern Tunisia, has been used intensively as a primary source to meet the growing needs of the various sectors. Detailed knowledge of the geochemical evolution of groundwater and water quality can enhance understanding of the hydrochemical system, promoting sustainable development and effective management of groundwater resources. To this end, a hydrochemical and statistical investigation was conducted. Groundwater samples have been collected from 13 wells from 1995 to 2005; to understand the sources of dissolved ions and assess the chemical quality of the groundwater. Results demonstrate that among the cations, only the mean concentrations of Na?+? exceed guideline values set by the World Health Organization (WHO). Regarding the analyzed anions, the concentration of SO $_{4}^{2-}$ and Cl??? are above the WHO allowable concentrations. Total dissolved solids in most groundwater samples are greater than 1,000 mg l???1, the limit set by the WHO, indicating slightly saline or moderately saline water. In general, a significant increase in the degree of water mineralization was observed in the direction of southwest to northeast following the regional flow direction. Calculated saturation indices show that all water samples were oversaturated with respect to aragonite, calcite, and dolomite, and undersaturated with respect to anhydrite, gypsum, and halite. Based on hydrochemical facies, two types of water predominate in the study area. The first is Ca?CNa?CSO4?CCl in type and located in the southwest which corresponds to the recharge part of the aquifer. The second type is Na?CCa?CCl?CSO4 and located in the east, which corresponds to the discharge part.  相似文献   

16.
The landscape-level and multiscale biodiversity monitoring program National Inventory of Landscapes in Sweden (NILS) was launched in 2003. NILS is conducted as a sample-based stratified inventory that acquires data across several spatial scales, which is accomplished by combining aerial photo interpretation with field inventory. A total of 631 sample units are distributed across the land base of Sweden, of which 20% are surveyed each year. By 2007 NILS completed the first 5-year inventory phase. As the reinventory in the second 5-year phase (2008?C2012) proceeds, experiences and insights accumulate and reflections are made on the setup and accomplishment of the monitoring scheme. In this article, the emphasis is placed on background, scope, objectives, design, and experiences of the NILS program. The main objective to collect data for and perform analyses of natural landscape changes, degree of anthropogenic impact, prerequisites for natural biological diversity and ecological processes at landscape scale. Different environmental conditions that can have direct or indirect effects on biological diversity are monitored. The program provides data for national and international policy and offers an infrastructure for other monitoring program and research projects. NILS has attracted significant national and international interest during its relatively short time of existence; the number of stakeholders and cooperation partners steadily increases. This is constructive and strengthens the incentive for the multiscale monitoring approach.  相似文献   

17.
Ken-Betwa river link is one of the pilot projects of the Inter Linking of Rivers program of Government of India in Bundelkhand Region. It will connect the Ken and Betwa rivers through a system of dams, reservoirs, and canals to provide storage for excess rainfall during the monsoon season and avoid floods. The main objective of this study is to identify erosional and inundation prone zones of Ken-Betwa river linking site in India using remote sensing and geographic information system tools. In this study, Landsat Thematic Mapper data of year 2005, digital elevation model from the Shuttle Radar Topographic Mission, and other ancillary data were analyzed to create various thematic maps viz. geomorphology, land use/land cover, NDVI, geology, soil, drainage density, elevation, slope, and rainfall. The integrated thematic maps were used for hazard zonation. This is based on categorizing the different hydrological and geomorphological processes influencing the inundation and erosion intensity. Result shows that the southern part of the study area which lies in Panna district of Madhya Pradesh, India, is more vulnerable than the other areas.  相似文献   

18.
The anthropogenic activity on the surface can modify and introduce new mechanisms of recharging the groundwatersystem, modifying the tax, the frequency and the quality ofrecharge of underground waters. The understanding of thesemechanisms and the correct evaluation of such modifications arefundamental in determining the vulnerability of groundwatercontamination. The groundwater flow of the South ParaíbaCompartment, in the region of São José dos Campos, São Paulo, is directly related to structural features of theTaubaté Basin and, therefore, the analysis of its behaviourenhances the understanding of tectonic structure. The methodologyadopted for this work consists in pre-processing and processing of the satellite images, visual interpretation of HSI products, field work and data integration. The derivation of the main structural features was based on visual analysis of the textureelements of drainage, and the relief in sedimentary and crystalline rocks. Statistical analysis of the feature densitiesand the metric-geometric relations between the analysed elementshave been conducted. The crystalline rocks, on which the sediments were laying, conditions and controls the structural arrangement of sedimentary formations. The formation of the SouthParaíba Grabén is associated with Cenozoic distensive movement which reactivated old features of crust weakness and generated previous cycles with normal characteristics. The environmental analysis is based on the integration of the existing methodology to characterise vulnerability of an universal pollutant and density fracture zone. The digital integration was processed using GIS (Geographic Information System) to delineate five defined vulnerability classes. The hydrogeological settings were analysed in each thematic map and,using fuzzy logic, an index for each different vulnerability class was compiled. Evidence maps could be combined in a seriesof steps using map algebra.  相似文献   

19.
Only organochlorine (OC) residues were monitored by gas chromatographyin water, sediment and shrimp samples collected everymonth between July 1982 and August 1983 from therivers of Rio Cobre basin. In samples collected everyfour months during 1989–1990, and seven times duringJuly 1995–March 1996, OC and OP (organophosphates)residues were monitored. Carbamate and pyrethroidresidues were not monitored. The detection ofresidues in 1982–1983 was 54 to 100% in water andsediment, and 83 to 100% in shrimp samples fromvarious sampling stations in the four rivers. In otheryears, it ranged from about 40 to 100% in the threetypes of samples.In 1982–1983, DDE and dieldrin residues were found tobe much higher than those of lindane and - and-endosulfan in Black River, Rio Pedro, ThomasRiver and Rio Cobre in the watershed. The ranges ofmeans of each residue in water (g L-1), sediment(ng g-1) and shrimp (ng g-1) samples, respectively, were:DDE, 0.059–102.0, 3.44–13.97, 0.344–14.57;dieldrin, 0.026–173.6, 1.21–2.75, 0.427–5.59;-endosulfan, bdl, 1.75–4.00, bdl;-endosulfan, bdl (below detectable limits), 2.51–9.48, bdl;and lindane, (bdl), 0.110–0.319, 2.90.In 1989–1990 and 1995–1996, residues of six OCs and two OPs were detected quite regularly. DDE, dieldrinand Chlorpyrifos residues were much higher than thoseof the other insecticides. The range of their meansin water (g L-1), sediment and shrimp (ng g-1),respectively, were: DDE, 1.66–19.76, 0.941–5.84,1.11–8.32; dieldrin, 0.077–7.22, 0.425–3.31,0.385–1.59; -endosulfan, 0.034–1.25, 0.021–1.22, 0.032–3.62; -endosulfan, 0.665–1.23,0.008–3.60, 0.005–3.97; endosulfan sulphate, 0.959–1.34, 0.035–3.08, 0.012–1.80; lindane, bdl,0.005–0.82, 1.19–1.56; chlorpyrifos, 0.702–4.06,0.005–1.51, 0.156–7.04; and diazinon, bdl, 0–0.150, 0.001–0.006. At the mouth of the river, whereit discharges into the sea, the levels of almost allthe residues were higher than upstream.  相似文献   

20.
Analysis of summer and winter vegetable samples during 2002–2003 for pesticidal contamination was carried out on Gas Chromatograph-Electron Capture Detector with capillary columns. The contamination levels of winter vegetables (average concentration of 4.57, 6.80 and 5.47 ppb respectively for Lindane, Endosulphan and DDT) were found to be slightly higher than the summer vegetables (average concentration of 4.47, 3.14 and 2.82 ppb respectively for Lindane, Endosulphan and DDT). The concentration of these organochlorine pesticides in summer and winter vegetables were well below the established tolerances but continuous consumption of such vegetables even with moderate contamination level can accumulate in the receptor's body and may lead to chronic effects that could be fatal.  相似文献   

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