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1.
A pilot and field investigation on mobility of PCDDs/PCDFs in landfill site with municipal solid waste incineration residue 总被引:4,自引:0,他引:4
A field investigation by boring was carried out in a landfill site primarily with municipal solid waste incineration residue. From the collected core samples, vertical profiles of homologous content of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) in the landfill layer were traced and the behavior of PCDDs/PCDFs was examined. In addition, a pilot-scale study was conducted on the PCDDs/PCDFs leached from incineration fly ash and the treated one using large landfill simulation columns (lysimeters) and the leaching behavior of PCDDs/PCDFs was examined. As a result, it was found that the coexistence of dissolved coloring constituents (DCCs), which might be composed of constituents like dissolved humic matters having strong affinity for hydrophobic organic pollutants, could enhance the leachability of PCDDs/PCDFs, thus contributing to the vertical movement and leaching behavior of PCDDs/PCDFs in the landfill layers of the incineration residue. Moreover, it is highly probable that DCCs derive from the unburned carbon in the bottom ash mixed and buried with the fly ash containing a high content of PCDDs/PCDFs. 相似文献
2.
This paper summarizes recent studies on the environmental fate of chloroaromatic compounds in chlorophenol (CP)-contaminated soil and groundwater at Swedish sawmill sites. Relative proportions of CPs, polychlorinated phenoxy phenols (PCPPs), polychlorinated diphenyl ethers (PCDEs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) were determined in preservatives, particulate organic matter (POM), dissolved organic matter (DOM), groundwater, and particles filtered from groundwater. All compound classes were found in the different compartments. The fraction of PCPPs, PCDEs, PCDDs, and PCDFs had increased in the soil samples relative to the proportions in the preservatives. This increase showed correlation with the hydrophobicity, that is, PCDDs had the largest increase. Similar correlation was found between hydrophobicity and the importance of partitioning to POM over DOM. The more water soluble compound group, CP, was found equally distributed between POM and DOM. For PCPPs, PCDEs, PCDDs, and PCDFs, the relative partitioning to POM increased with increased hydrophobicity. Despite the relative partitioning towards POM, compared with DOM, cotransport with DOM and suspended colloidal fractions was found to substantially increase the transport of these compounds in the groundwater samples. 相似文献
3.
The sampling procedure of solid and gaseous pollutants, contained in flue gas emitted into the atmosphere by solid waste incinerating furnaces were investigated. Because of their extraordinary toxicological properties, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are taken into particular consideration. The analytical work is based on the use of high-resolution gas chromatography in combination with low-resolution mass spectrometry. Details of the extensive sample clean-up will follow the GC-MS separation and identification of the isomers detected for each group of PCDDs and PCDFs. Quantitative data of these pollutants distribution levels deriving from different investigated incinerators are also reported. 相似文献
4.
The decrease of trichlorophenol by injecting oxidation catalyst into a municipal solid waste incinerator was monitored in real time. Direct sampling atmospheric pressure chemical ionization (APCI)/ion trap mass spectrometry (ITMS) was used for the real-time monitoring. The oxidation catalyst was iron oxide type, which exponentially reduced trichlorophenol emission. CO emission, however, did not show any correlation with the catalyst injection rate. Simultaneous analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs) suggested that real-time monitoring of trichlorophenol as a surrogate of PCDDs/PCDFs, has a potential to timely control the optimum injection rate of PCDD/PCDF suppression catalyst continuously and economically. 相似文献
5.
One bottle of Yusho rice oil was obtained from a Yusho family in 1998. The levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in the causal oil were investigated with two different approaches and the individual concentrations of all the 17 2,3,7,8-substituted PCDD/F and 14 coplanar PCB (Co-PCB) congeners were elucidated for the first time. The concentrations of PCDDs and PCDFs were found to be 0.60 and 8.8 ppm, respectively. For PCBs, more than 130 PCB peaks were observed and a total concentration of 850 ppm including 170 ppm of Co-PCBs was obtained. The toxic equivalents (TEQs) of PCDDs, PCDFs, and Co-PCBs were calculated to be 17, 470, and 120 ppb, respectively. The relative contribution of these classes to the total TEQ in Yusho oil is 3%, 77%, and 20%, respectively, indicating that PCDFs play a major role in the toxicity of Yusho oil. Furthermore, it was confirmed that 2,3,4,7,8-penta-CDF contributes 58% to the total TEQ, supporting the view that this compound is the principal causal agent in Yusho poisoning. It is noteworthy that the most toxic 2,3,7,8-tetra-CDD was newly discovered, although it contributes only 0.1% to the total TEQ. Based on our data, the smallest TEQ intake during the latent period was estimated to be 0.067 mg for Yusho patients. This value is about 60% of that previously reported, suggesting a lower minimum threshold level for the development of the toxic symptoms of Yusho. 相似文献
6.
Removal efficiencies of PCDDs/PCDFs by air pollution control devices in municipal solid waste incinerators 总被引:5,自引:0,他引:5
Kim SC Jeon SH Jung IR Kim KH Kwon MH Kim JH Yi JH Kim SJ You JC Jung DH 《Chemosphere》2001,43(4-7):773-776
Removal efficiencies of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) by air pollution control devices (APCDs) in the commercial-scale municipal solid waste (MSW) incinerators with a capacity of above 200 ton/day were evaluated. The removal efficiencies of PCDDs/PCDFs were up to 95% when the activated carbon (AC) was injected in front of electrostatic precipitator (EP). Spray dryer absorber/bag filter (SDA/BF) had high removal efficiency (99%)) of PCDDs/PCDFs when a mixture of lime and AC was sprayed into the SDA. When the AC was not added in scrubbing solution, the whole congeners of PCDDs/PCDFs were enriched in the wet scrubber (WS) with negative removal efficiencies of -25% to -5731%. Discharge of PCDDs/PCDFs was decreased with increasing the proportions of AC added in scrubbing solution. Selective catalytic reduction (SCR) system had the removal efficiencies of up to 93% during the test operation. 相似文献
7.
Levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in the breast milk of mothers living in Giugliano (Campania, Italy), an area at increased risk of PCDD and PCDF exposure caused by recent and serious open-air waste-combustion accidents. Polychlorinated biphenyls (PCBs) in milk samples were also studied. Breast milk was also monitored in two cities in northern Italy, Milan and Piacenza, which were selected as controls. Other variables, such as diet and age of the mothers, were also studied. PCDD/F and PCB levels and congener profiles in breast-milk samples were similar in all these cities, though total PCDD/F and DL-PCB TEQs in samples from Giugliano were significantly lower than those in Milan and Piacenza (8.65 pg WHO-TEQ in Giugliano vs. 11.0 and 9.94 pg WHO-TEQ in Milan and Piacenza respectively). Thus no direct correlations were found between PCDD/F and PCB levels in breast milk and the suspected increased exposure through open-air waste combustion in Giugliano. Diet did not seem to affect PCDD/F and PCB levels, whereas a significant correlation was observed between the mother’s age and an increased concentration of PCDDs/Fs and PCBs in milk. Comparison of these findings with those of previous surveys in Italy in 2000-2001 showed a marked reduction of PCDD/F (about 60%) and DL-PCB (about 20%) levels in breast milk occurring over the last 10 years. This might well be a result of well functioning legislation, for example European Directives on of the reduction of the emission limits of PCDDs/Fs and PCBs from waste incineration set by EU Directive 2000/76/EC implemented in 2000, or Commission Regulations such as (EC) No. 466/2001 and 1881/2006 setting maximum levels for certain contaminants in foodstuffs. 相似文献
8.
Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and non-ortho chlorine substituted coplanar polychlorinated biphenyl (Co-PCBs, non-ortho Cl CBs) in river and offshore sediment samples were analyzed isomer-specifically using (13)C-labeled their respective internal standards and a selected ion monitoring method of high resolution gas chromatograph-mass spectrometry (GC-MS). These compounds were found in all samples analyzed. The average concentrations of the total PCDDs, PCDFs and Co-PCBs in the 23 sediment samples taken from rivers were 11 000, 1300 and 160 pgg(-1) of dry wt, respectively, those in six offshore sediments were 7600, 980 and 52 pgg(-1), respectively. The concentrations of Co-PCBs were much lower than those of PCDDs and PCDFs in all sediment samples. The magnitude of these concentrations was in the order of lower reach of river > offshore area > upper reach of river. The concentrations of PCDDs and PCDFs in the rural river were higher than those in the urban river, whereas the Co-PCB concentration in an urban river was six times higher than that in a rural river. The Co-PCB concentrations in the urban area and industrial area were higher than that in any other area. These findings suggest that the pollution by PCDDs and PCDFs was derived from some kinds of incinerations and herbicides applied in the past and that Co-PCB pollution was caused by PCB preparation used in the past in urban and industrial areas and by municipal waste incineration in urban areas. 相似文献
9.
Feasibility of three different extraction methods for the simultaneous determination of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in butter is discussed. The method based on liquid-liquid extraction with water of the non fatty solids from butter dissolved in hexane was found to be the most efficient for the determination of the lipid content and the levels of the investigated pollutants. This method was used to evaluate the background levels of PCBs, PCDDs and PCDFs in butters commercially available in Spain. Broad ranges of PCB, specifically, PCDD and PCDF concentrations were found in the different brands analysed. Levels, profiles and patterns of these pollutants in butter were compared with those previously reported for different Spanish dairy products. The toxic tetra-equivalents of 2,3,7,8-TCDD (1-TEQ) averages for PCDDs and PCDFs in the 21 butter samples analysed were 0.41 and 0.70 pg/g fat basis, respectively. These values were similar or lower than those cited in the literature for other countries. 相似文献
10.
The aim of the project was to measure the actual emissions of polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and hexachlorobenzene (HCB) from four selected power plants in Poland in order to update the national inventory of PCDDs/PCDFs emission. Relatively low PCDDs/PCDFs as well as dl-PCBs concentrations in flue gas obtained in measurements in this study for four different circulated fluidized bed (CFB) boilers indicate practical absence of any hazards caused by PCDDs/PCDFs emission from these units. The results of PCDDs/PCDFs determination obtained in this study indicate that hard coal combustion in large CFB in the four central heating plants (CHP) is not a significant source of PCDDs/PCDFs emission to the environment even if operated by co-firing of waste coal. PCDDs/PCDFs concentration in flue gases as well as emission factors were recorded in the range of 0.012-0.060ngI-TEQ/m(n)(3) and 7.51-46.4mugI-TEQ/TJ, respectively. Dl-PCBs concentration was practically below the LOQ=0.006ng WHO-PCB TEQ/m(n)(3) in all experiments. HCB concentration as well as emission factors were recorded in the range of 11.5-42.0ng/m(n)(3) and 6.19-26.7mg/TJ, respectively, where the highest value was obtained for co-firing of waste coal, however. Obtained in this work emission factors will be used for national emission inventory purposes instead of the factors proposed by Toolkit or taken from previous measurements. However, consideration should be given to the fact that the measurements in most cases are related to single installations. Therefore, the need for further development of national factors for the power generation industry in Poland is desired. 相似文献
11.
Yamashita N Tanabe S Ludwig JP Kurita H Ludwig ME Tatsukawa R 《Environmental pollution (Barking, Essex : 1987)》1993,79(2):163-173
Persistent organochlorine contaminants including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were determined in eggs with normal and deformed embryos collected in 1988 from different colonies during an epizootiological survey of double-crested cormorants (Phalacrocorax auritus) and Caspian terns (Hydroprogne caspia) from the upper Great Lakes. PCBs and p,p'-DDE were found in the highest concentrations in eggs of both species. The residue pattern of PCB isomers and chlordane compounds suggested that double-crested cormorants have greater metabolic capacity to degrade contaminants than Caspian terns. According to the toxicity evaluation using the 2,3,7,8-TCDD equivalents (TEQs) approach, non-ortho coplanar PCBs contributed much more toxicity than PCDDs and PCDFs. Total TEQ of dioxin-like compounds was likely associated with occurrence of live-deformed embryos in double-crested cormorants eggs. The toxic effects of these contaminants were also estimated in Caspian tern eggs, where elevated levels of coplanar PCBs, PCDDs and PCDFs were observed in concordance with increased rate of anomalies in eggs during a breeding season in the Great Lakes. 相似文献
12.
Formation and emission status of PCDDs/PCDFs in municipal solid waste incinerators in Korea 总被引:5,自引:0,他引:5
Kim SC Jeon SH Jung IR Kim KH Kwon MH Kim JH Yi JH Kim SJ You JC Jung DH 《Chemosphere》2001,43(4-7):701-707
This study was carried out to examine the formation and the emission status of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) in the flue gases of commercial-scale municipal solid waste (MSW) incinerators, and thus to provide the engineering data for the reduction of PCDDs/PCDFs emitted from MSW incinerators. The formation concentrations of the PCDDs/PCDFs generated at the outlet of waste heat boilers (WHB) were in the range of 1.18-29.61 ng-TEQ/N m3 (average 5.75 ng-TEQ/N m3), while the emission concentrations at the stacks were in the range of 0.026-4.548 ng-TEQ/N m3 (average 0.924 ng-TEQ/N m3). Two major 2,3,7,8-substituted congeners were 2,3,4,7,8-PeCDF and 2,3,4,6,7,8-HxCDF, and their concentrations were up to 50% and 64% of total TEQ values at the outlet of WHB and the stack, respectively. From the results of multi-regression analysis, the formation concentration of PCDDs/PCDFs could be predicted as follows with the correlation factor of r2 = 0.962: PCDDs/PCDFs (ng-TEQ/N m3) = 3.036 (Cl) + 0.094 (T1) - 0.472 (Combustibles) + 0.059 (CO) - 0.039 (THC) - 3.366 (H) + 22.157, where T1 (degrees C) is the temperature at the outlet of the WHB. Cl, Combustibles and H are given as percentages and the others are in parts per million. 相似文献
13.
V. Ozvacic G. Wong H. Tosine R. E. Clement J. Osborne 《Journal of the Air & Waste Management Association (1995)》2013,63(8):849-855
In this paper the results of sampling for trace chlorinated organics at two municipal refuse incinerators in Ontario are presented. The information may be of Interest to individuals concerned with the assessment of PCDD/PCDF (polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran) emissions from incineration of refuse and their impact on the energyfrom- waste program. PCDDs, PCDFs, PCBs (polychlorinated biphenyls), CBs (chlorobenzenes) and CPs (chlorophenols) were quantified in all process streams including refuse, ash and stack emissions. Manual sorting of refuse and collection of ash samples were carried out simultaneously with three 24-hour continuous stack sampling tests at each plant. The results suggested that the total output of PCDDs and PCDFs varied proportionately with their input at both incinerators. However, the input of PCDDs/PCDFs could not account for their total output. The chemistry of PCDDs/PCDFs in the input and output streams were different in that only heptachlorinated and octachlorinated species were present in significant quantities in the refuse while lower chlorinated species were predominant in stack emissions and ash streams. There was no correspondence between the Input of PCBs/CBs/CPs and the output of PCDDs/PCDFs. The output of PCDDs/PCDFs, however, varied Inversely with the total output of PCBs/CBs/CPs, suggesting that the latter compounds could have been partially responsible for the formation of PCDDs and PCDFs. The PCDF emissions were also affected by combustion conditions; they were higher in magnitude and consisted of predominantly tetrachlorinated and pentachlorinated species at the plant where the combustion temperatures were lower. 相似文献
14.
The catalytic effects of copper and iron compounds were examined for their behavior in promoting formation of chlorine (Cl2), the major chlorinating agent of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), in an environment simulating that of municipal waste fly ash. Formation of Cl2 occurred as a result of a metal-catalyzed reaction of HCl with O2. Catalytic activity was greatest at a temperature of approximately 400 °C, supporting a theory of de novo synthesis of PCDDs and PCDFs on fly ash particles downstream of waste combustion. 相似文献
15.
Liver of blue shark (Prionace glauca) specimens from the South-Eastern Mediterranean Sea were analyzed for the presence of polychlorinated biphenyls (PCBs), including coplanar congeners, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). PCBs were the dominant chemicals, followed by PCDFs and PCDDs. The pattern of PCB congener concentrations in the hepatic tissue was dominated by higher chlorinated compounds. The specific profile of toxic PCDD/F congeners was characterized mainly by 2,3,7,8-TCDF and 2,3,7,8-TCDD, followed by 1,2,3,6,7,8-HxCDD and 2,3,4,6,7,8-HxCDF. The total 2,3,7,8-TCDD toxic equivalent (TEQs) was 149 pg g−1 lipid wt. The profile of TEQ shows that PCDDs present the greatest risk to this species contributing to total toxicity with a percentage approximately of 60%, while the contribution of PCDFs and DL-PCBs is almost the same being 22.4% and 21.6%, respectively. Further investigations are urgently needed to characterize the PCDD/Fs contamination levels not only in elasmobranch fish but in all Mediterranean marine biota. 相似文献
16.
Ohta M Oshima S Iwasa T Osawa N Kumatoriya K Yamazaki A Takasuga T Matsushita M Umedzu N 《Chemosphere》2001,44(6):1389-1394
In laboratory-scale combustion of polyvinylidene chloride (PVDC) with a quartz tubular furnace designed and fabricated to provide the desired combustion temperature and mixing state of combustion gas with air, it was found that at 800 degrees C or higher the level of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans [corrected] (PCDDs/PCDFs) resulting from PVDC combustion was no higher than that from heating air alone, and thus far below the levels which resulted from PVDC combustion at 750 degrees C or lower. The results provide the first laboratory confirmation of the relation between PVDC incineration temperature and PCDD/PCDF formation, and of the primary importance of high temperature, turbulence for mixing between air and combustion gas, and sufficient residence time, as governing factors for the minimization of PCDD/PCDF formation in municipal solid waste incinerators. 相似文献
17.
PCDDs, PCDFs, and PCBs concentrations in breast milk from two areas in Korea: body burden of mothers and implications for feeding infants 总被引:3,自引:0,他引:3
We determined breast milk concentration of polychlorinated dibenzo-p-dioxins (PCDDs)/polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in 24 mothers living in Korea, and assessed the maternal body burden based on PCDDs/PCDFs and PCBs concentrations in breast milk and an infant intake rate through breast-feeding based on their concentration in breast milk. PCDDs/PCDFs and PCBs levels in breast milk from primipara mothers were found to be higher than those from multipara mothers. For total PCDDs/PCDFs TEQ level, 2,3,4,7,8-PeCDD was the predominant congener, and the proportion of 2,3,7,8-TCDD was less than 3% of total PCDDs/PCDFs TEQ level. For PCBs TEQ level, PCB-126 was the predominant congener. Maternal body burden levels of PCDDs/PCDFs and PCBs based on their concentrations in breast milk were 268-622 TEQ ng. The daily dioxin intakes of mothers were predicted to be 0.78-2.18 TEQ pg/kg/day for PCDDs/PCDFs and 0.34-0.66 TEQ pg/kg/ day for PCBs. For the first year, the body burden of an infant was predicted to be 212 TEQ ng and the daily intake of an infant was predicted to be 85 TEQ pg/kg/day, assuming the mean dioxin-related compounds concentration (27.54 TEQ pg/g fat). 相似文献
18.
Five fluidized bed incinerators combusting municipal solid waste were assessed for the impact of coplanar PCBs on total TEQ emission. In 17 stack measurements, the coplanar PCBs contributed on average less than 3% to total TEQ with a maximum contribution of 7.5% to total TEQ in one measurement. Differences in the design of the flue gas cooling section did not show an effect on the impact of coplanar PCBs on total TEQ. The effect of emission control devices on the impact of coplanar PCBs on the total TEQ was studied in more detail at one incinerator. The relative contribution of PCBs to total TEQ increased along the flue gas line. This was caused by a slightly higher removal efficiency for TEQ relevant PCDDs/PCDFs compared to coplanar PCBs by the bag filters and a higher destruction efficiency for PCDDs/PCDFs compared to PCBs by the SCR catalyst. Additionally, the removal efficiencies of the emission control devices (bag filters and catalyst) for other chlorinated aromatic compounds which have been proposed as TEQ indicator compounds (polychlorinated benzenes and polychlorinated phenols) were compared with those for PCDDs/PCDFs and coplanar PCBs. Removal efficiencies for polychlorinated benzenes or polychlorinated phenols considerably differed from those of PCDD/PCDF and coplanar PCBs. Implications for TEQ assessments using indicator compounds as proposed in the literature are discussed. 相似文献
19.
Bates MN Buckland SJ Garrett N Ellis H Needham LL Patterson DG Turner WE Russell DG 《Chemosphere》2004,54(10):1431-1443
Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and organochlorine pesticides were measured in the serum of a sample of the New Zealand population aged 15 years and older. This was the first study to obtain representative measures of PCDDs, PCDFs and PCBs in the adult population of an entire country. Serum samples were obtained in 1996-1997. Potentially occupationally exposed individuals were excluded. Serum samples were pooled according to stratification criteria for area of residence, ethnicity, age, and sex. Of the 80 possible strata, sufficient serum for chemical analysis was available for 60, to which 1,834 individual samples contributed. For the PCDDs and PCDFs, most 2,3,7,8-chlorinated congeners were measured in all strata, with a mean toxic equivalents concentration across all strata of 12.8 ng TEQ kg(-1) lipid. Seven PCB congeners were frequently measured, including the coplanar congeners #126 and #169, quantified in all strata. Of the pesticides and their metabolites, only beta-HCH, dieldrin and pp'-DDE were consistently detected across strata. There was a general trend of increasing concentration with age. There were no consistent differences between the sexes, or between people of Maori (the indigenous people of New Zealand) and non-Maori ethnicity. Concentrations of PCDDs and PCDFs tended to increase in a North-South direction, possibly reflecting greater levels of industrialization and population concentration, and concentrations of the pesticide products were highest in the South, possibly reflecting historical use patterns. Results were consistent with a recent study of concentrations of these compounds in the milk of first-time mothers. 相似文献
20.
To investigate the leaching characteristic of persistent organic pollutants (POPs), such as non-ortho and mono-ortho substituted chlorobiphebyls (dioxin-like PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs), in leachate from municipal solid waste (MSW) landfill sites containing incineration residues, raw leachate samples were collected twice from 12 selected MSW landfill sites. The samples were divided into their liquid and solid phases using GF/B (pore size 1.0 microm), and the concentrations of POPs then determined. The concentrations of PCDDs/DFs ranged from 0.65 to 5.88 pg-TEQ/l (average 2.86 pg-TEQ/l), and those of dioxin-like PCBs from 0.05 to 0.32 pg-TEQ/l (average 0.18 pg-TEQ/l). The major congeners of leached PCDDs/DFs and dioxin-like PCBs in liquid and solid phases were OCDD (about 60%), 2,3',4,4',5-PeCBs (about 30%), and 2,3,4,4',5-PeCBs (about 54%). The relationship between landfill age and the leaching concentration of PCDDs/DFs, and effects of dissolved organic carbon (DOC) on the leaching of PCDDs/DFs are also discussed. Finally, a leaching prediction model of PCDDs/DFs from MSW landfills has been suggested using parameters, such as hydrophobic neutral organic carbons, total dissolved solid, and the ratio of non-biodegradable wastes in landfill sites. 相似文献