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1.
Data on dioxin-like PCB in indoor air of buildings with PCB-containing materials and on possible correlation between toxicity equivalent concentrations (TEQ) and levels of non-dioxin-like standard PCB is sparse. As part of a larger survey on indoor-air contamination with PCB, the connection between the concentration of standard PCB congeners and the dioxin-like toxicity expressed as TEQ was investigated. Indoor air samples (n=8) were collected in four public buildings with known PCB sources and total PCB levels in the range from 715 to 2250 ng/m3 and analyzed for the six non-dioxin-like standard PCB (congeners 28, 52, 101, 138, 153, 180), the twelve dioxin-like PCB congeners according to WHO and the 17 2,3,7,8-substituted PCDD/PCDF congeners. In three buildings where PCB were used as flame retardant coatings of acoustic ceiling tiles, PCB 101 had the maximum level among the six standard PCB, while in the building with permanent elastic sealants as PCB source, congeners 28 and 52 dominated the pattern by far. In the case of permanent elastic sealants as PCB source (n=3) a total PCB concentration of 1000 ng/m3 corresponded to a total TEQ level of 0.3-0.6 pg/m3. In contrast, in rooms with acoustic ceiling tiles as PCB source, 1.8-4.7 pg TEQ/m3 per 1000 ng total PCB/m3 were found. Linear regression analysis between PCB and TEQ indicated that PCB 118 might be used to calculate the total TEQ of dioxin-like PCB and PCDD/PCDF. By means of such a correlation it is possible to estimate TEQ by extrapolation from the results of less sophisticated analytical methods. It is tentatively recommended to use PCB 118 for screening purposes or re-evaluation of standard PCB indoor-air measurements. If only the six non-dioxin-like PCB standard congeners are available, a regression algorithm using the sum of PCB 101, 138, 153 and 180 might be used instead.  相似文献   

2.
A cod liver oil reference material, Standard Reference Material (SRM) 1588, which was issued by the National Institute of Standards and Technology (NIST) in 1989, has certified concentrations for five polychlorinated biphenyl (PCB) congeners and ten chlorinated pesticides. Recently, this SRM has been extensively characterized by additional analyses at NIST and by analyses at the Canadian Wildlife Service (CWS) where the SRM was used as a control sample during routine analyses of wildlife tissue specimens. In this paper the results from NIST and CWS are compared and the concentrations for over 40 PCB congeners and 20 chlorinated hydrocarbons are reported.  相似文献   

3.
PCB concentrations were studied in different soils to determine the spatial variation over a region of approximately 11 000 km(2). PCB congener pattern was used to illustrate the spatial differences, as shown by principal component analysis (PCA). The relationship to different soil parameters was studied. PCB concentrations in soil showed a large variation between sampling-areas with median concentrations ranging between 2.3 and 332 ng g(-1) (dw). Highest concentrations were found at two sites with sandy soils, one with extremely high organic carbon content. Both sites were located on the west coast of southern Sweden. Soils with similar soil textures (i.e. sandy silt moraine) did not show any significant differences in PCB concentrations. PCB congener composition was shown to differ between sites, with congener patterns almost site-specific. PCB in air and precipitation was measured and the transfer of chemicals between the soil and air compartments was estimated. Soil-air fugacity quotient calculations showed that the PCBs in the soil consistently had a higher fugacity than the PCBs in the air, with a median quotient value of 2.7. The gaseous fluxes between soil and air were estimated using standard modelling equations and a net soil-air flux estimated by subtracting bulk deposition from gaseous soil-air fluxes. It was shown that inclusion of vertical sorbed phase transport of PCBs in the soil had a large effect on the direction of the net soil-air exchange fluxes.  相似文献   

4.
Homologue and congener profiles of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in commercial PCBs formulations are key information for the source identification of PCBs contamination as well as for the risk assessment caused by potential exposure. The isotope dilution technology in combination with high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) has made the accurate determination of such profiles possible. So far, various commercial PCB formulations except Chinese products have been successfully determined. Two PCBs containing insulating oil samples from stored Chinese electrical capacitors have been determined with the same methodology for comparability. The total concentration PCBs in two oil samples were 790 000 μg g−1 and 720 000 μg g−1, respectively. TriCBs, TetraCBs, and DiCBs were found to be most abundant. Concentration of dioxins contamination in two samples is 650-670 ngTEQ g−1, of which 69-71 ngTEQ g−1 from PCDD/Fs with the predominant congeners of 1,2,7,8-TeCDF; 2,3,7,8-TeCDF; 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDF. The contributions of DL-PCBs in total TEQ in both samples were more than 85%. The dioxin-like toxicity in insulating oils contained in electrical capacitors could be considered receive attention as an important dioxins source if such wastes are not managed in an environmentally sound manner.  相似文献   

5.
Chlorohydrocarbons, PCB congeners, polychlorodioxins, furans and dibenzothiophenes in pine needles in the vicinity of a metal reclamation plant were analyzed by GC/ECD and GC/MS. Wax and the rest of the needles were analyzed separately. As a rule the concentrations of -HCH (0.5–13.6 ng/g), γ-HCH (0.4–7.3 ng/g), HCB (0.2–3.4 ng/g), PCB congeners (0.2–67 ng/g), PCDDs and PCDFs were higher in the older needles. The ratio of the concentration in the wax to the concentration in the rest of the needles was higher in the younger needles. The concentrations of PCB congeners, TeCDDs and TeCDFs were higher in the needles collected in the area nearest to the plant. The samples, obviously, contained tri- and tetrachlorodibenzothiophenes but these were not determined quantitatively due to interfering peaks in GC/MS.  相似文献   

6.
A photochemical smog model system, the Variable-Grid Urban Airshed Model/Systems Applications International Mesoscale Model (UAM-V/SAIMM), was used to investigate photochemical pollution in the Bangkok Metropolitan Region (BMR). The model system was first applied to simulate a historical photochemical smog episode of two days (January 13-14, 1997) using the 1997 anthropogenic emission database available at the Pollution Control Department and an estimated biogenic emission. The output 1-hr ozone (O3) for BMR, however, did not meet the U.S. Environmental Protection Agency suggested performance criteria. The simulated minimum and maximum O3 values in the domain were much higher than the observations. Multiple model runs with different precursor emission reduction scenarios showed that the best model performance with the simulated 1-hr O3 meeting all the criteria was obtained when the volatile organic compound (VOC) and oxides of nitrogen (NOx) emission from mobile source reduced by 50% and carbon monoxide by 20% from the original database. Various combinations of anthropogenic and biogenic emissions in Bangkok and surrounding provinces were simulated to assess the contribution of different sources to O3 pollution in the city. O3 formation in Bangkok was found to be more VOC-sensitive than NOx-sensitive. To attain the Thailand ambient air quality standard for 1-hr O3 of 100 ppb, VOC emission in BMR should be reduced by 50-60%. Management strategies considered in the scenario study consist of Stage I, Stage II vapor control, replacement of two-stroke by four-stroke motorcycles, 100% compressed natural gas bus, 100% natural gas-fired power plants, and replacement of methyltertiarybutylether by ethanol as an additive for gasoline.  相似文献   

7.
Indiana Harbor and Ship Canal (IHSC) is an active navigational system that serves a heavily industrial area of southern Lake Michigan. We have determined the amount of polychlorinated biphenyls (PCBs), congener distributions, sorbent types and potential for dioxin-like PCB toxicity from two IHSC sediment cores. Vertical distributions of ΣPCBs (sum of 161 individual or coeluting congeners) ranged from 410 to 91000 and 1800 to 41000 ng g(-1) dry weight (d.w.) for cores 1 and 2, respectively. Core 1 showed its highest accumulation rate for the year ~1979 and exhibits a strong Aroclor 1248 signal in sediments accumulating over the last 60 years. It appears that from the late 1930s until the beginning of the 1980s there was a large and constant input of PCBs into this system. This pattern differs from lake cores from the Great Lakes region which commonly exhibit a rapid increase, a peak, followed by a sharp decrease in the PCB accumulation rates. Core 2 also has a strong Aroclor 1248 signal in the top layers, but deeper layers show evidence of mixtures of Aroclors and/or weathering processes. High levels of black carbon as a fraction of total organic carbon were found in both cores (median ~30%), which reflect the long history of local combustion sources. No strong relationship was found between ΣPCB concentration and sorbents. Both cores contain dioxin-like PCBs that are highest in concentration below the surface. The high levels of PCBs in the deep sediments are of concern because of plans to dredge this system.  相似文献   

8.
Complex mixtures extracted from air filters exposed for 24 h in two sessions (27 July and 02 August 1991) and at two locations (Merced, downtown, and Pedregal de San Angel, south-west) in Mexico City were analysed. The organic extracts were from airborne particles equal or smaller than 10 microns (PM10), and from total suspended particles (TSP). These organic extracts were assayed in the somatic mutation and recombination test (SMART) in wings of Drosophila melanogaster using two different crosses as well as in the Salmonella/microsome assay using strain TA98 with and without S9 fraction. The presence of polycyclic aromatic hydrocarbons (PAH) in the extracts was determined by gas chromatography. The genotoxic activities observed in the two test systems were comparable with the indirect mutagens producing greater response than the direct mutagens. The quantities of particulate matter as well as the genotoxic activities were higher on 02 August than on 27 July 1991 for both locations. The amounts of airborne particles and the resulting genotoxic activities were higher at Merced than at Pedregal. In both biological systems, PM10 were more genotoxic than TSP. These results demonstrate the sensitivity of the Drosophila wing SMART-which is an in vivo eukaryotic genotoxicity assay-as a biological monitor of environmental pollution related to airborne particles.  相似文献   

9.
南宁市郊空气和大气干湿沉降物中多环芳烃的污染特征   总被引:4,自引:0,他引:4  
采用空气被动采样器和大气干湿采样器分夏、冬季采集大气及其干湿沉降物样品,利用气相色谱-质谱联用仪测定16种多环芳烃(PAHs)优先控制污染物。结果表明:冬、夏季大气干湿沉降物中PAHs的平均值分别为581.06、174.59ng/(m2·d),冬季PAHs的组成以2~3环PAHs为主,夏季以4~6环PAHs为主;冬、夏季空气中PAHs的平均值分别为149.16、168.70ng/d,均以2~3环PAHs为主。大气干湿沉降物PAHs的沉降通量时空变化为:冬季,商住文教混合区农业区工业区;夏季,工业区农业区商住文教混合区;冬季大于夏季3.3倍。空气PAHs沉降通量的时空变化为:冬季,工业区商住文教混合区农业区;夏季,农业区工业区商住文教混合区;冬季略低于夏季。  相似文献   

10.
The motorcycle taxi drivers of Bangkok have been heavily exposed to high concentrations of PM10 (particulate matter with an aerodynamic diameter ≤10 μm), and the impact of this on their lungs has been neither documented nor studied. This study examines the association between exposure to PM10 and lung function decline among motorcycle taxi drivers. A cross-sectional study was conducted in Bangkok between two groups: a subject group of motorcycle taxi drivers and control group of enclosed vehicle taxi drivers. The findings of the Thailand Pollution Control Department were used to estimate the annual ambient PM10 concentration levels in the metropolis. Pulmonary functions of motorcycle taxi drivers and enclosed vehicle taxi drivers were measured and compared using the Mann-Whitney test. Multiple linear regression analysis was applied to estimate the effects of PM10 exposure on the lung function of motorcycle taxi drivers. A total of 1283 motorcycle taxi drivers and 600 taxi drivers were investigated. The mean forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC) of the motorcycle taxi drivers was significantly lower than that of the taxi drivers (P < 0.001). The mean FEV1/FVC of motorcycle taxi drivers exposed to ≥50 µg/m3 PM10 was statistically lower (?2.82%; 95% confidence interval [CI]: ?4.54% to ?1.09%) and the mean % vital capacity (%VC) of those exposed to 40–49.9 µg/m3 PM10 was statistically lower than that of motorcycle taxi drivers exposed to <30 µg/m3 PM10 (?3.33%; 95% CI: ?5.79% to ?0.87%). Motorcycle taxi drivers were directly exposed to air pollution in their working environment. As a result, their lung function might decrease more than that of enclosed vehicle taxi drivers. With the possible exposure to ≥50 µg/m3 PM10, the vehicular emission standards should be vigorously enforced. Further investigation is warranted to clarify the effect of lung dysfunction on the work and lifestyle of motorcycle taxi drivers.

Implications: Motorcycle taxi drivers are directly exposed to air pollution in their work environment; therefore, their lung function might decrease more than that of enclosed vehicle taxi drivers, especially when exposed to ≥50 µg/m3 PM10. World Health Organization (WHO) vehicular emission standards should be recognized and eventually enforced.  相似文献   

11.
The expansion of urbanization introduces air pollution to wildlife areas. Some metal contaminants occurring in concentrations too small to have any measurable impact on adult birds may seriously affect embryos that are more sensitive to contaminants than the adult. Chromium, manganese, and lead are toxic and can be passed from the hen to the egg. This study relates the concentrations of these metals in eggs to their concentrations in air in three cities. Rock dove eggs were sampled and air pollution records were examined in the California cities of Riverside, Los Angeles, and San Francisco. The eggs from San Francisco did not differ from those of Los Angeles in lead concentration but the air did differ. The eggs collected in Los Angeles in 1998 had concentrations of chromium greater than in those from Riverside and from Los Angeles 1999 but the air had concentrations of chromium that did not differ among those three collections. Concentrations of manganese did not differ among the eggs but did differ among the air samples of the three cities. Exposures of embryos to chromium and manganese in this study were not at levels warranting concern. Although the concentration at which lead in eggs impairs avian health is not established, the highest concentrations found in this study exceed estimated safe concentrations. There is no indication that embryo exposure is directly related to atmospheric levels of these metals in the cities of this study.  相似文献   

12.
This paper describes the analysis of hazardous waste oil samples with procedures that were developed primarily to clean up and analyze biological samples. Details of the cleanup procedure and the results from the analysis of several waste PCB oil samples are presented.  相似文献   

13.
The uptake and release of PCB isomers and congeners were examined in green-lipped mussels (Perna viridis) through a transplantation experiment in two locations in Hong Kong waters. Rapid rates of uptake and release of relatively less lipophilic lower-chlorinated PCBs were observed in the mussels, indicating that the primary mechanism of bioaccumulation of lipophilic pollutants in P. viridis complies with the concept of equilibrium partitioning. Thus, data for contaminant concentrations are most appropriately based upon lipid weights of samples when using mussels as bioindicators of aquatic PCB pollution. Considering the kinetic parameters of PCBs based on lipid weight-related data, it is concluded that P. viridis has the ability to respond rapidly to changes in ambient levels of PCBs. This is significant in determining the usefulness and limitations of mussels as bioindicators for monitoring programmes investigating aquatic pollution by PCBs.  相似文献   

14.
Sue Yai Utit is an old community located in Bangkok, Thailand which dismantles waste electrical and electronic equipment (WEEE). The surface soil samples at the dismantling site were contaminated with copper (Cu), lead (Pb), zinc (Zn), and nickel (Ni) higher than Dutch Standards, especially around the WEEE dumps. Residual fractions of Cu, Pb, Zn, and Ni in coarse soil particles were greater than in finer soil. However, those metals bonded to Fe-Mn oxides were considerably greater in fine soil particles. The distribution of Zn in the mobile fraction and a higher concentration in finer soil particles indicated its readily leachable character. The concentration of Cu, Pb, and Ni in both fine and coarse soil particles was mostly not significantly different. The fractionation of heavy metals at this dismantling site was comparable to the background. The contamination characteristics differed from pollution by other sources, which generally demonstrated the magnification of the non-residual fraction. A distribution pathway was proposed whereby contamination began by the deposition of WEEE scrap directly onto the soil surface as a source of heavy metal. This then accumulated, corroded, and was released via natural processes, becoming redistributed among the soil material. Therefore, the concentrations of both the residual and non-residual fractions of heavy metals in WEEE-contaminated soil increased.  相似文献   

15.
Human milk samples from women in Middle Hesse, Germany were chemically analyzed for contamination levels of alpha-, beta- and gamma-HCH, HCB, p,p'-DDE and p,p'-DDT as well as the PCB-congeners no. 28, 31, 49, 52, 101, 118, 138, 153, 156, 170 and 180. Changes in concentrations of these compounds in human milk over an extended time period were studied by comparing samples from 1984/85, 1990/91 and 1995. In addition, concentrations of the nitro-aromatic compounds musk xylene and musk ketone were determined in the 1995 samples. The study showed statistically highly significant (p<0.001) reductions in levels of beta- and gamma-HCH, HCB, p,p'-DDE and p,p'-DDT, in human milk from 1995 compared to samples from 1984/85. A weakly significant reduction (p<0.05) of alpha-HCH was also observed. For low-chlorinated PCB congeners, on the other hand, a highly significant increase of PCB no. 28 was detected and concentrations of congeners no. 31, 49 and 52 remained unchanged. Concentrations of the high-chlorinated congeners no. 101, 138, 153 and 180 dropped (highly significant). A highly significant reduction of PCB no. 118 and 156 occurred between 1990/91 and 1995, but a highly significant increase was found for no. 170. Lower levels of hydrocarbon contamination of human milk samples from 1995 than were found in samples from 1984/85 and 1990/91 can be seen to result partially from voluntary reductions, but primarily reflect restrictive environmental legislation in the Federal Republic of Germany. Mean concentrations of musk xylene and musk ketone in samples from 1995 were 41 microg/kg and 10 microg/kg milk fat, respectively.  相似文献   

16.
Environmental Science and Pollution Research - The concentrations of short-chain polychlorinated paraffins (SCCPs) in the urban air of Dalian, China, were monitored from March to October 2010 and...  相似文献   

17.
18.
Unhatched eggs were collected in 1988 and 1990 from nests of the Eurasian Dipper Cinclus cinclus and the Grey Wagtail Motacilla cinerea in Wales, eastern Scotland and south-western Ireland. Mercury concentrations in Dipper eggs (geometric means 0.45-0.91 ppm (microg g(-1)) dry mass) were significantly lower in eastern Scotland than in either south-western Ireland or Wales, where the incidence of detectable residues increased markedly between 1988 (2% of eggs) and 1990 (69%). By contrast, DDE (geometric means 0.63-3.54 ppm in lipid), TDE (<0.01-1.80 ppm), DDT (<0.01-0.65 ppm), total PCBs (3.99-10.47 ppm), HEOD (0.39-0.61 ppm) and HCB (0.02-0.13 ppm) were all significantly higher in Scottish eggs than others. Around 33-46% of the total PCB burden in Dipper and Grey Wagtail eggs could be accounted for by six congeners (IUPAC numbers 118, 180, 101, 153, 138 and 170). Amongst these attributable PCBs, Dipper eggs from eastern Scotland were dominated by congener 153 (2,2',4,4',5,5'-hexachlorobiphenyl), whilst Welsh and Irish eggs were dominated by congener 118 (2,3',4,4',5-pentachlorobiphenyl). With the latter exception, all the individual congeners were found at significantly higher concentrations in Scottish eggs than others. Grey Wagtail eggs were dominated by congeners 118 and 101 (2,2,4,5,5'-pentachlorobiphenyl). In general, these congeners are common, widespread, and dominant components in the eggs of other wild birds for which data are available. Consistent with the low to medium levels of contaminants found in Dipper eggs, there was only slight evidence of any toxic effects. These included moderate shell thinning in relation to increasing DDE, and some evidence that contaminants had contributed to egg failure.  相似文献   

19.
Total suspended particulate (TSP) samples have been collected at six stations in the C and B lines of the Buenos Aires underground system and, almost simultaneously, at six ground level sites outside and nearby the corresponding underground stations, in the Oct 2005/Oct 2006 period. All these samples were analyzed for mass and elemental Fe, Cu, and Zn concentrations by using the Particle Induced X-ray Emission (PIXE) technique. Mostly, TSP concentrations were found to be between 152 μg m−3 (25% percentile) and 270 μg m−3 (75% percentile) in the platform of the stations, while those in outside ambient air oscillated from 55 μg m−3 (25% percentile) to 137 μg m−3 (75% percentile). Moreover, experimental results indicate that TSP levels are comparable to those measured for other underground systems worldwide. Statistical results demonstrate that subway TSP levels are about 3 times larger on average than those for urban ambient air. The TSP levels inside stations and outdoors are poorly correlated, indicating that TSP levels in the metro system are mainly influenced by internal sources.Regarding metal concentrations, the most enriched element in TSP samples was Fe, the levels of which ranged from 36 (25% percentile) to 86 μg m−3 (75% percentile) in Line C stations, while in Line B ones they varied between 8 μg m−3 (25% percentile) and 46 μg m−3 (75% percentile). As a comparison, Fe concentrations in ambient air oscillated between 0.7 μg m−3 (25% percentile) and 1.2 μg m−3 (75% percentile). Other enriched elements include Cu and Zn. With regard to their sources, Fe and Cu have been related to processes taking place inside the subway system, while Zn has been associated with outdoor vehicular traffic. Additionally, concerns about possible health implications based on comparisons to various indoor air quality limits and available toxicological information are discussed.  相似文献   

20.
Antunes P  Amado J  Vale C  Gil O 《Chemosphere》2007,69(3):395-402
Concentrations of 30 polychlorinated biphenyl congeners (CBs) were determined in muscle, liver and gonad tissues of female and male sardines (Sardina pilchardus) collected in February-May 2000 and September-January 2001 from purse seine vessels operating around Peniche, Portugal. The determined CBs were aggregated in four groups (I, II, III and IV), according to similarities of their chemical structures. Muscle and liver of males contained significantly higher concentrations of groups I and II than females during the final period of spawning (February-April). A less contrast was observed for the groups III and IV. This seasonal fluctuation associated with the spawning indicates that female sardines regulate the excess of CBs sequestrated during fatten period. On the contrary, levels of groups I and II were higher in males than in females indicating slower mobility of these compounds as lipids were consumed during the final period of spawning. The deficient regulation of those CBs in muscle of male sardines can not be attributed to selective transfer to gonads and subsequent excretion. Although the full explanation was not found for the different mobility of PCBs with the gender, the results provide evidence of slower elimination of group I and II congeners in male sardines.  相似文献   

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