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1.
Manual and automatic welding machines (which use leaded alloys) are considered to be important sources of the emission of lead fumes into the general air of the working environment. Three workplaces at a television factory were selected for the present study, to determine the control class of the working unit. The concentrations of conventional measurements ("A" sampling points) were lower than the administrative control level (statutory standard of lead, 150 microg m(-3)), whereas the maximum concentration of 264.1 microg m(-3) ("B" sampling point) was higher at one working unit than the administrative control level. However, the control classes varied between class III (bad) and class I (good).  相似文献   

2.
Evaluation and analysis of noise pollution levels have been carried out to determine the level of noise and its sources in Ilorin metropolis. Noise measurements have been done in the morning, at noon, in the evening, and at night to determine noise pollution all over the city. The selected areas of study are commercial centers, road junctions/busy roads, passenger loading parks, and high-density and low-density residential areas. The road junctions had the highest noise pollution levels, followed by commercial centers. The results of this study show that the noise levels in Ilorin metropolis exceeded allowed values at 30 of 42 measurements points. There is a significant difference (P?<?0.05) in the noise pollution levels and traffic noise index in all the locations. From the measured noise values, a map of noise pollution was developed for Ilorin. Many solutions proposed for noise abatement in the city are set out.  相似文献   

3.
Examination of car fleet records in Accra demonstrates an increasing proportion of catalytic converter-equipped cars in the relatively old car fleet (average age 13 years) due to their import from developed countries. However, only leaded petrol is sold in Ghana. Lead anti-knocking additives, which are known to affect catalyst activity and promote thermal sintering and mechanical abrasion, may increase Pt emissions. This possible synergism prompted the concomitant determination of Pb and Pt levels in road dust and roadside soils in Ghana. Both metals followed traffic density with higher concentrations in urban areas compared to remote sites. In urban areas, the range for Pb (365 +/- 93 microg g(-1) for dust and 291 +/- 76 microg g(-1) for soil) reflects precatalyst levels in Europe and the US, while the range for Pt (39 +/- 24 ng g(-1) for dust and 15 +/- 5.3 ng g(-1) for soil) is typical for the same countries. The elevated Pt concentrations were unexpected due to recent introduction of catalysts to Ghana compared to the prolonged use of catalysts in Europe and the US.  相似文献   

4.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) in street soil dust from streets in Kumasi Metropolis in the Ashanti Region of the Republic of Ghana have been measured in this study. The concentrations of the various types of PAHs identified in this study are as follows: Naphthalene (m/e 128) – 41,700 μg/kg, Acenaphthylene (m/e 152) – 99,300 μg/kg, Acenaphthene (m/e 154) – 111,200 μg/kg, Fluorene (m/e 166) – 8,900 μg/kg, Carbazole (m/e 167) – 3,500 μg/kg, phenathrene (m/e 178) – 12,900 μg/kg, Anthracene (m/e 178) – 5,400 μg/kg, Fluoranthene (m/e 202) – 16,200 μg/kg, Pyrene (m/e 202) – 15,000 μg/kg, Benzo[a]anthracene (m/e 228) – 13,800 μg/kg, Chrysene (m/e 228) – 33,600 μg/kg, Benzo[k]fluoranthene (m/e 252) – 45,700 μg/kg, Benzo[a]pyrene (m/e 252) – 27,900 μg/kg, Perylene (m/e 252) – 57,200 μg/kg and Benzo[g, h, i]perylene (m/e 276) – 47,000 μg/kg. The results of the study shows that road users, like resident living in buildings within these areas, those engaged in commercial activities like hawking, and the general public are at risk of exposure to the toxic effects of the various types of PAHs from the exhaust of vehicles into the environment. According to these results, there is the potential for exposure to high levels of PAHs for road users and those living in urban environments or along highways.  相似文献   

5.
Assessment of lead in blood (BLL) and lead in urine (ULL) of some non-occupationally exposed, nonsmoking 214 pregnant Nigerian women, aged 17 to 49 years, and resident in Lagos was carried out using atomic absorption spectrometry with control subjects consisting of 113 nonpregnant women. From results, the mean BLL and ULL (μg/dL) for pregnant women (59.5 ± 2.1; 29.4 ± 1.1) were significantly (p?<?0.01) higher than the values obtained for nonpregnant women (27.7 ± 1.1; 9.2 ± 0.6). BLL found in women in the first, second, and third trimesters were 57.2 ± 2.3, 61.6 ± 2.2, and 63.1 ± 1.8, respectively. ULL could not serve to predict BLL due to weak correlations (r?=???0.06 to +?0.15; p?>?0.10). Study is a contribution to blood and urine lead status of Nigerian pregnant women, being relevant for healthcare management purposes, public health decision making, and possible primary prevention activities.  相似文献   

6.
The Barekese reservoir has seen persistent degradation for decades through anthropogenic activities within its catchment. In spite of this, heavy metal pollution profile of fish species of the reservoir is not well studied. Total concentrations of Hg, Cd, Ni, and Cr were analyzed in muscle tissues of 45 edible fish species comprising (Tilapia zilli, Oreochromis niloticus, and Heterotis niloticus) from the reservoir. The examined fish species showed varying bioaccumulative factors for detected metals. A PCA biplot revealed that Cd showed association with all examined fish species used in the study indicating that Cd in the reservoir is biologically available for uptake by all examined fish species. A dendrogram of cluster analysis also revealed that Cd and Cr are in one cluster indicating their associations and similarities to a common anthropogenic source. The study suggests that anthropogenic activities are possible sources of heavy metal pollution in the Barekese reservoir and, hence, the examined fish species could be used to monitor the levels of Ni, Cr, Hg, and Cd in the reservoir.  相似文献   

7.
兰州市小儿血铅水平与环境铅污染关系调查   总被引:6,自引:0,他引:6  
采用随机抽样的方法对兰州市103对新生儿及其母亲、1月至36月的146名婴幼儿以及808名3~7岁儿童的毛细血管血铅进行了分析,同时对上述幼儿园室内外尘土或土壤样品采用石墨炉原子吸收法进行了铅分析测定,通过相关分析,说明城市环境铅污染是小儿血铅升高的主要原因之一。  相似文献   

8.
A survey to assess the occurrence of airborne fungal spores in three different industries, dairies, carpentries and greenhouses, was carried out. The results revealed considerable fungal pollution in the environments of the industries sampled. Noteworthy was the occurrence of fungal genera frequently implicated in allergic and non-allergic diseases, or well known for the production of mycotoxins in foods or characterized by a marked degradative activity on different substrata. Penicillium, Candida, Mucor and Geotrichum were the most common genera identified in the dairies; Penicillium, Cladosporium, yeasts, Trichoderma and Rhizopus occurred more frequently in the carpentries; Cladosporium, Alternaria, Penicillium and Stemphilium were prevailing in the greenhouse.The results of our survey support the idea that, due to their high incidence and variety, fungal spores may represent a potential health hazard in working environments, where their concentration can be affected by many operations and handling.  相似文献   

9.
Cd, Ni, Cr, Zn, Cu and Pb concentrations of muscle tissue of 61 fish samples belonging to six fish species (Sparus auratus, Pomatomus saltatrix, Sarda sarda, Engraulis encrasicholus, Sander lucioperca, Scomber scombrus) retailed in Kayseri, Turkey were determined by flame atomic absorption spectrometry after wet digestion. Cd concentrations of at least 31 fish samples (50.8%) and Pb concentrations of at least six fish samples (9.8%) exceeded the corresponding Turkish permissible limit of 0.05 and 0.2 mg kg(-1) respectively whereas Zn concentrations of 11 fish samples (18%) exceeded the Turkish Food Codex limits of 50 mg kg(-1) for Zn. Cu concentrations of all fish species analyzed (100%) were below the corresponding Turkish legislations of 20 mg kg(-1). No limits were established concerning Ni and Cr concentrations in fish by the Turkish governmental authorities.  相似文献   

10.
The study aims were to: (i) investigate long term human lead metabolism by measuring the change of lead concentration in the tibia and calcaneus; and (ii) assess whether improved industrial hygiene was resulting in a slow accumulation of lead in an exposed workforce. 109Cd excited K X-ray fluorescence was used to measure tibia lead and calcaneus lead concentrations in 101 workers in a secondary lead smelter. 51 subjects had had similar bone lead measurements 5 years previously. Most of the other subjects had been hired since the first survey. Measurements of whole blood lead were available for the large majority of subjects. Tibia lead concentrations fell significantly (p<0.001) in the 51 subjects with repeated bone lead measurements, from a mean of 39 microg Pb (g bone mineral)(-1) to 33 microg Pb (g bone mineral)(-1). The change correlated negatively with the initial tibia lead concentration, producing an estimate for an overall half-life of 15 years, with a 95% confidence interval of 9 to 55 years. Adding continuing lead exposure and recirculation of bone lead stores to the regression models produced half-life estimates of 12 and 9 years, respectively, for release of lead from the tibia. The repeat subjects showed no net change in calcaneus lead (64 microg Pb (g bone mineral)(-1) initially, 65 microg Pb (g bone mineral)(-1) 5 years later). Subjects not measured previously had average lead concentrations of 15 microg Pb (g bone mincral)(-1) in the tibia and 13 microg Pb (g bone mineral)(-1) in the calcaneus. The rate of clearance of lead from the tibia (9 to 15 years) is towards the more rapid end of previous estimates. The lack of a significant fall in the calcaneus lead was surprising. Attempts should be made to repeat this observation. If confirmed, it would have implications for models of lead metabolism. The relatively low lead concentrations in the non-repeat subjects are reassuring. However, observation after a longer period of employment would be desirable.  相似文献   

11.
Personal and area samples for airborne lead were taken at a lead mine concentrator mill, and at a lead-acid battery recycler. Lead is mined as its sulfidic ore, galena, which is often associated with zinc and silver. The ore typically is concentrated, and partially separated, on site by crushing and differential froth flotation of the ore minerals before being sent to a primary smelter. Besides lead, zinc and iron are also present in the airborne dusts, together with insignificant levels of copper and silver, and, in one area, manganese. The disposal of used lead-acid batteries presents environmental issues, and is also a waste of recoverable materials. Recycling operations allow for the recovery of lead, which can then be sold back to battery manufacturers to form a closed loop. At the recycling facility lead is the chief airborne metal, together with minor antimony and tin, but several other metals are generally present in much smaller quantities, including copper, chromium, manganese and cadmium. Samplers used in these studies included the closed-face 37 mm filter cassette (the current US standard method for lead sampling), the 37 mm GSP or "cone" sampler, the 25 mm Institute of Occupational Medicine (IOM) inhalable sampler, the 25 mm Button sampler, and the open-face 25 mm cassette. Mixed cellulose-ester filters were used in all samplers. The filters were analyzed after sampling for their content of the various metals, particularly lead, that could be analyzed by the specific portable X-ray fluorescence (XRF) analyzer under study, and then were extracted with acid and analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The 25 mm filters were analyzed using a single XRF reading, while three readings on different parts of the filter were taken from the 37 mm filters. For lead at the mine concentrate mill, all five samplers gave good correlations (r2 > 0.96) between the two analytical methods over the entire range of found lead mass, which encompassed the permissible exposure limit of 150 mg m(-3) enforced in the USA by the Mine Safety and Health Administration (MSHA). Linear regression on the results from most samplers gave almost 1 ratio 1 correlations without additional correction, indicating an absence of matrix effects from the presence of iron and zinc in the samples. An approximately 10% negative bias was found for the slope of the Button sampler regression, in line with other studies, but it did not significantly affect the accuracy as all XRF results from this sampler were within 20% of the corresponding ICP values. As in previous studies, the best results were obtained with the GSP sampler using the average of three readings, with all XRF results within 20% of the corresponding ICP values and a slope close to 1 (0.99). Greater than 95% of XRF results were within 20% of the corresponding ICP values for the closed-face 37 mm cassette using the OSHA algorithm, and the IOM sampler using a sample area of 3.46 cm2. As in previous studies, considerable material was found on the interior walls of all samplers that possess an internal surface for deposition, at approximately the same proportion for all samplers. At the lead-acid battery recycler all five samplers in their optimal configurations gave good correlations (r2 > 0.92) between the two analytical methods over the entire range of found lead mass, which included the permissible exposure limit enforced in the USA by the Occupational Safety and Health Administration (OSHA). Linear regression on the results from most samplers gave almost 1 ratio 1 correlations (except for the Button sampler), indicating an absence of matrix effects from the presence of the smaller quantities of the other metals in the samples. A negative bias was found for the slope of the button sampler regression, in line with other studies. Even though very high concentrations of lead were encountered (up to almost 6 mg m(-3)) no saturation of the detector was observed. Most samplers performed well, with >90% of XRF results within +/- 25% of the corresponding ICP results for the optimum configurations. The OSHA algorithm for the CFC worked best without including the back-up pad with the filter.  相似文献   

12.
Samples of tree bark, which accumulate airborne material, were collected from seven locations in the UK to provide an indication of the magnitude and source of lead pollution. Measurement of the Pb content and 206/207Pb stable isotope ratio by inductively coupled plasma mass spectrometry revealed significant differences between the sites. The concentration of Pb varied over almost four orders of magnitude from 7.2 to 9,600 micrograms g-1, the maximum values being found near a 'secondary' Pb smelter. The 206/207Pb isotope ratios varied from 1.108 +/- 0.002 to 1.169 +/- 0.001. The lowest Pb concentrations and highest isotope ratios were detected in bark samples from the Scilly Isles, reflecting the low-level of industry and road traffic. In contrast, samples obtained from a city centre (Sheffield) and near a motorway (M1) contained 25-46 micrograms g-1 Pb and recorded the lowest 206/207Pb ratios. Higher concentrations in the vicinity of a coal-fired power station recorded a 206/207Pb ratio of 1.14, suggesting a significant contribution from fly-ash. The relative contribution of lead from petrol (206/207Pb = 1.08) and other sources such as coal (206/207Pb = 1.18) were thus estimated using mass balance equations. Tree bark near the lead smelter recorded an intermediate 206/207Pb ratio of 1.13 reflecting the processing of material of mixed origin.  相似文献   

13.
An analytical method for ethylene glycol and propylene glycols has been developed for measuring airborne levels of these chemicals in non-occupational environments such as residences and office buildings. The analytes were collected on charcoal tubes, solvent extracted, and analyzed by gas chromatography-mass spectrometry using a positive chemical ionization technique. The method had a method detection limit of 0.07 microg m(-3) for ethylene glycol and 0.03 microg m(-3) for 1,2- and 1,3-propylene glycols, respectively, based on a 1.44 m3 sampling volume. Indoor air samples of several residential homes and other indoor environments have been analyzed. The median concentrations of ethylene glycol and 1,2-propylene glycol in nine residential indoor air samples were 53 microg m(-3) and 13 microg m(-3) respectively with maximum values of 223 microg m(-3) and 25 microg m(-3) detected for ethylene glycol and 1,2-propylene glycol respectively. The concentrations of these two chemicals in one office and two laboratories were at low microg m(-3) levels. The maximum concentration of 1,3-propylene glycol detected in indoor air was 0.1 microg m(-3).  相似文献   

14.
Total mercury (Hg) concentrations were determined in the muscle tissue of fish from three reservoirs in Ghana, namely, Lake Bosomtwi, Kpong and Akosombo Hydroelectric Reservoirs. A total of 165 fish samples covering nine species were collected and analysed for total mercury. A mixture of HNO3, H2SO4 and HClO4 were used for complete oxidation of organic tissues. Hg was detected by the Cold Vapour Atomic Absorption Spectrometry technique using an automatic mercury analyzer. Total mercury concentrations in microg g(-1) (wet weight) ranged from below 0.001 to 0.070 for fish from Lake Bosomtwi, 0.010 to 0.275 for fish from Kpong Reservoir and from below 0.001 to 0.042 for fish from Akosombo Reservoir. All the results obtained are below the World Health Organization limit of 0.5 microg g(-1). The low levels of total mercury obtained in this study suggest that the three aquatic environments have not been significantly impacted by mercury contamination.  相似文献   

15.
We analyzed national data on blood lead levels (BLL) and blood cadmium levels (BCL) in residents living near 38 abandoned metal mining areas (n?=?5,682, 18–96 years old) in Korea that were collected by the first Health Effect Surveillance for Residents in Abandoned Metal mines (HESRAM) from 2008 to 2011. The geometric mean BCL and BLL were 1.60 μg/L (95 % CI?=?1.57–1.62 μg/L) and 2.87 μg/dL (95 % CI?=?2.84–2.90 μg/dL), respectively, notably higher than levels in the general population in Korea and other countries. We found significantly higher BLL and BCL levels in people living within 2 km of an abandoned metal mine (n?=?3,165, BCL?=?1.87 μg/L, BLL?=?2.91 μg/dL) compared to people living more than 2 km away (n?=?2,517, BCL?=?1.31 μg/L, BLL?=?2.82 μg/dL; P?<?0.0001) and to the general population values reported in the literature.  相似文献   

16.
We examined the selectivity of 53 sets of primers for environmental monitoring of indoor air quality. Thirty-six fungal strains, representing 26 species from 14 genera of commonly occurring fungi, and 16 different bacterial strains, representing both gram-negative and gram-positive species, were included in the experiment. We verified the specificity of 28 of the 53 sets of primers, which were classified as universal fungal, universal bacterial, group or species specific. The PCR conditions required for optimal specificity were also determined. These results can serve as a guide for the step-wise PCR-based detection and identification of airborne fungi commonly found in indoor environments.  相似文献   

17.
The Respicon has been introduced as a sampler for health related measurements of airborne contaminants at workplaces. The instrument is aimed at simultaneous collection of three health related aerosol fractions: (a) the coarser inhalable fraction, defining the aerosol fraction that may enter the nose and mouth during breathing; (b) the intermediate thoracic fraction, defining the fraction that may penetrate beyond the larynx and so reach the lung; and (c) the finer respirable fraction, defining the fraction that may penetrate to gas exchange region of the lung. The instrument has a number of features attractive to occupational hygienists: in addition to providing the three aerosol fractions simultaneously, it is light and compact enough to be used as a personal sampler. yet can be a tripod mounted for area sampling, it can provide samples not only for gravimetric analysis but also microscopic and chemical analyses; and it is also available in a photometric direct-reading version. The instrument has previously been evaluated as an area sampler and, in this mode of operation, has shown reasonable accuracy in collecting respirable, thoracic and inhalable particles, the latter up to particle diameters of ca. 80 microm. Except for some scattered unpublished data there exist no systematic investigations in the Respicon's performance when used as a personal sampler in the industrial environment. In this paper, we will report on a study of side by side comparison of the Respicon with the IOM inhalable sampler, regarded as a reference instrument for the inhalable fraction. The main study was performed at six different workplaces in a nickel refinery. Statistical analysis of the gravimetrically-determined concentration data reveals consistently lower aerosol exposure values for the Respicon as compared to the IOM sampler. The data for the nickel workplaces are compared with findings from other studies. The results are interpreted in the light of the overall results and the possibility of introducing a correction factor is discussed.  相似文献   

18.
In 2007, as part of the control and prevention of environmental contamination threatening public health, the Korean Ministry of Environment planned to implement a national biomonitoring survey of three metals: lead, cadmium, and mercury in the blood of residents living near 350 abandoned metal mines known to be contaminated and as possible threats to the health of inhabitants. Thus, we investigated demographic and lifestyle variables and blood lead levels in residents living around the mines and compared them against those of control subjects. We measured the blood lead concentrations in 14,849 subjects (14,132 from nearby the 350 abandoned metal mines and 717 subjects from eight control areas). A questionnaire was provided to all subjects to determine gender, age, mining experience, period of time living in the vicinity of mines, smoking status, and personal perception of abandoned mines as a health risk. The geometric means (95% confidence intervals) of the blood lead levels of residents living around the abandoned metal mines and control areas were 3.017 (2.996-3.037 μg/dL) [female, 2.797 μg/dL (2.771-2.822 μg/dL); male, 3.330 μg/dL (3.298-3.363 μg/dL)] and 2.757 (2.677-2.837 μg/dL) [female, 2.604 μg/dL (2.506-2.700 μg/dL); male, 2.993 μg/dL (2.859-3.126 μg/dL)], respectively. Among residents of the mining areas, nonsmokers and residents who had no mining experience showed significantly lower mean blood lead levels than did smokers, past smokers, and those with mining experience. The mean blood lead concentrations of residents who expressed some concern about the abandoned mines were significantly higher than those of residents without concerns. The mean blood lead concentration of residents living around the abandoned mines was significantly higher than that of residents living in control areas as well as that of the general adult Korean population. We also confirmed that smoking is an important variable to consider, as it increases blood lead concentration.  相似文献   

19.
Iran imports nearly 55,000 tons of Chrysotile asbestos per year and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, airborne asbestos concentrations during AC sheet manufacturing were measured. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM), with energy-dispersive X-ray analysis. Airborne total fiber concentrations of 45 personal samples were analyzed by phase contrast microscopy. The results have highlighted that 15.5% of samples exceed the threshold limit value (TLV) established the American Conference of Governmental Industrial Hygienists, which is 0.1 fiber per milliliter (f/ml). Personal monitoring of asbestos fiber levels indicated a ranged from 0.02?±?0.01 to 0.16?±?0.03 f/ml. The geometrical mean was 0.05?±?1.36 f/ml, which is considerably lower than the TLV. SEM data demonstrate that the fibrous particles consisted, approximately, of Chrysotile (55.89%) and amphiboles (44.11%). We conclude that the industrial consumption of imported Chrysotile asbestos is responsible for the high airborne amphibole asbestos levels in the AC sheet industry. More research is needed to improve characterization of occupational exposures by fiber size and concentration in a variety of industries.  相似文献   

20.
The heavy metals (Fe, Zn, Pb, Ni, Cr, Co, and Cd) burden in wastewater, soil, and vegetable samples from a wastewater irrigated farm located at KorleBu, Accra has been investigated. Flame atomic absorption spectrometry after microwave digestion using a combination of HNO3, HCl, and H2O2 (for water), and HNO3 and HCl (for soil and vegetables). The mean concentrations (in milligrams per kilogram) of heavy metals in the soil samples were in the order of Fe (171?±?5.22)?>?Zn (36.06?±?4.54)?>?Pb (33.35?±?35.62)?>?Ni (6.31?±?8.15)?>?Cr (3.40?±?3.63)?>?Co (1.36?±?0.31)?>?Cd (0.43?±?0.24), while the vegetables were in the order of Fe (183.11?±?161.2)?>?Zn (5.38?±?3.50)?>?Ni (3.52?±?1.27)?>?Pb (2.49?±?1.81)?>?Cr (1.46?±?0.51)?>?Co (0.66?±?0.25)?>?Cd (0.36?±?0.15). The bioconcentration factors suggest environmental monitoring for the heavy metals as follows: Cd (0.828), Cr (0.431), Ni (0.558), Co (0.485), and Fe (1.067). Estimated daily intakes were very low for both children and adults except Fe (0.767 mg/kg/day) in children. The population that consume vegetables from the study area were, however, estimated to be safe based on the results obtained from the health risk index, which were all?<?<1. The sodium absorption ratio according to FAO (1985) classifications indicate that the wastewater in the study area is unsuitable for irrigation purposes.  相似文献   

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