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Polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) (collectively PCDD/Fs) are toxic and persistent contaminants produced as unintentional by-products of anthropogenic activities. Human exposure to PCDD/Fs occurs primarily through consumption of contaminated food, though point-source soil contamination can also meaningfully contribute to exposure. Environmental soil quality guidelines (ESQGs) for PCDD/Fs have been developed worldwide. In Canada, the 2002 federal ESQG of 4 ng/kg has been adopted by most provinces and is based on limited background soil data. In the remaining provinces, ESQGs derived to be protective of human health range from 15 ng/kg to 95 ng/kg. Internationally, 70% of human health protective ESQGs adopted since 2010 range from 20 ng/kg to 120 ng/kg. Considering the consistency in human health protective ESQGs observed worldwide, the ongoing inputs of PCDD/Fs to the environment and the evolving scientific understanding of PCDD/F toxicity over the last two decades, the federal ESQG appears outdated. As ESQGs are of specific importance in the management of contaminated sites, they must remain protective of human health without being unreasonably cautious. Federal agency review and update of the ESQG for PCDD/Fs appears warranted and should consider the establishment of a risk-based guideline protective of human health. [ABSTRACT FROM AUTHOR]

Municipal solid waste incinerator (MSWI) not only is deemed one of the uppermost sources of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), but also produces substantial amount of polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) owing to the existence of brominated flame retardants (BFRs) in the waste. So far, however, PBDD/Fs in the vicinal environments of MSWI and their associated risks remain rarely studied. Based on a one-year passive air sampling (PAS) scheme, we investigated airborne PBDD/Fs and PCDD/Fs around a large-scale MSWI that has been operated for multi-years. Both the concentrations of PBDD/Fs and PCDD/Fs showed spatially decreasing trends with the distance away from the MSWI, confirming the influence of the MSWI on the dioxin levels in its ambient air. But its influence on PBDD/Fs was less because PBDD/Fs exhibit lower volatility and therefore lower gaseous concentrations than PCDD/Fs. Compared to the existing global data of airborne PCDD/Fs and PBDD/Fs, our data of the MSWI vicinity were at medium levels, despite PAS samples only represent the concentrations of gaseous dioxins in theory. The seasonal data suggest that meteorological conditions exerted apparent influences over the concentrations and sources of airborne dioxins around the MSWI. As for PCDD/Fs, the MSWI was diagnosed as their uppermost source, followed by local traffic and volatilization/deposition. Whereas the top three PBDD/F sources were related to PBDEs, bromophenol/bromobenzene, and traffic vehicles, respectively. The bioassay-derived TEQs based on the aryl hydrocarbon receptor activation of airborne dioxins around the MSWI were one or two orders of magnitudes higher than their concentration-based TEQs, and the corresponding carcinogenic risks at some MSWI-vicinal sites exceeded the acceptable threshold proposed by the U. S. EPA (10−6 ∼ 10−4) and deserve continuous attention.

Flotation sludge from the meat processing industry can be applied as biofuel in already existing plant‐scale boilers. This biosolid is rich in oil and grease and has higher energetic content on a dry ash‐free basis (22.74 and 27.71 MJ kg−1) than the wood‐based fuel (16.62 and 16.16 MJ kg−1). Co‐combustion trials were performed at a pilot‐scale cyclonic combustor (100 kg h−1) and at an industrial flamotubular rotatory grate‐fired system (6000 kg h−1), co‐firing pre‐dried and centrifuged flotation sludges (respectively) and wood at a mass ratio of 1:3. At a moisture content of 60.13 wt%, the lower heating value of the centrifuged sludge was 10.24% lower compared to wood, thus reducing it to at least 40 wt% would be advisable to obtain energy gains in the industrial plant when operating the co‐combustion. The emissions were evaluated and compared to emission standards, including the characterization of polycyclic aromatic hydrocarbons and polychlorinated dibenzo‐p‐dioxins and polychlorinated dibenzofurans (given as Toxicity Equivalent Factors at O2ref = 7%), which have not yet been reported. The 16 target polycyclic aromatic hydrocarbons were identified at pilot and plant scales (0.582 ± 0.143 μg Nm−3 and 0.602 ± 0.506 μg Nm−3, respectively) being lower than the Danish reference standard (5.0 μg Nm−3). The polychlorinated dibenzo‐p‐dioxins and polychlorinated dibenzofurans concentrations were 0.0004 ± 0.0001 ng Nm−3 at pilot scale and 0.3617 ± 0.1310 ng Nm−3 at plant scale, both below the Brazilian and American standards but differed greatly between the scales, requiring further investigation since their formation can occur due to combustion and postcombustion conditions. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the influence of soil parameters (total inorganic and organic carbon, pH, particle size distribution, initial contaminant levels) on the performance of a leaching process to remove As, Cr, Cu, pentachlorophenol (PCP), and polychlorodibenzo-dioxins and furans (PCDD/F) from the fine fractions (< 0.250 mm) of various contaminated soils. The chemical treatment, including three leaching steps (pulp density (PD) = 10% (w.w−1), [BW] = 3% (w.w−1), [NaOH] = 0.85 M, retention time (t) = 2 h and temperature (T) = 80°C) followed by two rinsing steps (PD = 10% (w.w−1), T = 20°C, t = 15 min), was optimized in previous works. Five soil samples (S1 to S5 – from different location on the same industrial site) were used to study the effect of the initial contaminant levels. The results showed good performance of the leaching process used to simultaneously remove PCP (96–98%) and PCDD/F (57–81%). These results also highlighted that the initial concentration of PCP and PCDD/F slightly influenced the performance of the leaching process. Subsequently, this leaching process was applied to three different soils (F1 to F3). The results showed that this process was efficient in removing PCP (50–86%) and PCDD/F (41–45%) regardless of the nature of the soil studied. However, the results also showed that the organic matter content and the particle size slightly influenced the efficiency of the leaching process to remove PCP. [ABSTRACT FROM AUTHOR]

The concentrations of polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) were analyzed in 40 plasma samples of individuals living in zones under potential influence of the emissions of a hazardous waste incinerator (HWI) (Tarragona County, Catalonia, Spain). Samples corresponded to subjects of different gender, age and specific areas of residence. The levels of PCDD/Fs were compared to those obtained in a baseline study (1998), as well as in previous surveys (2002, 2007 and 2012). The current mean concentration of PCDD/Fs in plasma was 6.79 pg I-TEQ/g lipid, which was significantly lower than the baseline concentration (27.0 pg I-TEQ/g lipid). A significant decrease was also observed in comparison to the results obtained in 2002 and 2007 (15.7 and 9.4 pg I-TEQ/g, respectively), while the current PCDD/F levels were similar to those obtained in 2012 (6.18 pg I-TEQ/g lipid). This important reduction in plasma PCDD/F levels is in accordance with the decreasing trend in the daily dietary intake of PCDD/Fs, which diminished from 210.1 pg I-TEQ (baseline) to 8.54 pg WHO-TEQ (current). OCDD was the predominant congener in plasma, while 2,3,7,8-TeCDD and 1,2,3,4,7,8,9-HpCDF showed the lowest levels. Based on the above results, as well as other recent data on the levels of PCDD/Fs in human milk, we conclude that the presence of the HWI does not mean additional and significant risks –as regards to PCDD/F exposure-for the population living in the neighborhood of the facility. • PCDD/Fs were analyzed in plasma samples of individuals living near a HWI. • The current mean PCDD/F concentration in plasma was significantly lower than the baseline level. • The reduction in plasma agrees with the decreasing trend in the dietary intake of PCDD/Fs. • PCDD/Fs exposure from the HWI does not mean additional significant health risks. [ABSTRACT FROM AUTHOR]

Previously to the modernization of the municipal solid waste incinerator (MSWI) of Campdorà (Girona, Catalonia, Spain) two sampling campaigns (2015 and 2016) were conducted. In each campaign, 8 soil and 4 air samples (PM 10 and total particle phase and gas phase) were collected. The levels of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Sn, Tl and V, and PCDD/Fs were analysed at different distances and wind directions around the MSWI. Environmental levels of trace elements and PCDD/Fs were used to assess exposure and health risks (carcinogenic and non-carcinogenic) for the population living around the facility. In soils, no significant differences were observed for trace elements and PCDD/Fs between both campaigns. In air, significant higher levels of As, Cd, Co, Mn, Ni, Pb, Tl and V were detected in 2016. Regarding soil levels, only Cd (distances) and As, Cu, Mn, and Ni (wind directions) showed significant differences. No differences were noted in the concentrations of trace elements and PCDD/Fs in air levels with respect to distances and directions to the MSWI. No differences were registered in air levels (elements and PCDD/Fs) between points influenced by MSWI emissions and background point. However some differences in congener profile were noted regarding from where back-trajectories come from (HYSPLIT model results), pointing some influence of Barcelona metropolitan area. The concentrations of trace elements and PCDD/Fs were similar -or even lower- than those reported around other MSWIs in Catalonia and various countries. Non-carcinogenic risks were below the safety limit (HQ < 1). In turn, carcinogenic risks due to exposure to trace elements and PCDD/Fs were in acceptable ranges, according to national and international standard regulations. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-p-furans (PCDF) are widely distributed in the environment. The diverse production processes that form these compounds lead to a range of chemical signatures although weathering may cause changes to these signature over time and with increasing distance from their origin. Chemical signatures in sediments based on 17 PCDD/Fs were developed in Concepcion, a Chilean city in the middle of a complex hydrological system which contains several small urban freshwater bodies and the River Bio-Bio. The region has numerous industrial and domestic activities that may contribute PCDD/Fs to the environment. Sediments from urban lakes had higher concentrations of dioxins and furans (mean = 941 ng·kg − 1 ) than either a remote lake (335 ng·kg − 1 ) located 32 km from the city or marine samples (mean = 124 ng·kg − 1 ). Up to 85% of the compounds present in all sediment samples could be explained by the chemical signature associated with airborne particulates leaving only 15–30% of the chemical signature potentially arising from other sources. The remote lake had higher proportions of the less-chlorinated compounds compared to the urban samples. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the influence of the soil parameters (particle size, initial contamination level, etc.) on the performances of an attrition process to remove As, Cr, Cu, pentachlorophenol (PCP) and dioxins and furans (PCDD/F). Five different contaminated soils were wet-sieved to isolate five soil fractions (< 0.250, 0.250-1, 1-4, 4-12 and > 12 mm). Five attrition steps of 20 min each, carried out in the presence of a biodegradable surfactant ([BW] = 2%, w w) at room temperature with a pulp density fixed at 40% (w w), were applied to the coarse soil fractions (> 0.250 mm) of different soils. The results showed good performances of the attrition process to simultaneously remove PCP and PCDD/F from contaminated soil fractions initially containing between 1.1 and 13 mg of PCP kg (dry basis) and between 1795 and 5720 ng TEQ of PCDD/F kg. It appeared that the amounts of contaminants removed were significantly correlated ( p value < 0.05, R = 0.96) with the initial amounts of PCP and PCDD/F, regardless of the particle size of the soils studied. The nature of the soil (granulometric distribution, pH, total organic carbon (TOC) (organic matter) and diverse industrial origin) slightly and negatively influenced the efficiency of organic contaminants removals using attrition. However, the attrition treatment allowed an efficient removal of both PCP and PCDD/F from the coarse fraction of contaminated soil, despite the nature of the soil. [ABSTRACT FROM AUTHOR]

Nitrogen oxides (NOx) and polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) are well known as hazardous pollutants that may be generated during combustion processes, and which simultaneous removal is highly desired. Here the Selective Catalytic Reduction of NO by methane (CH 4 -SCR) with the simultaneous oxidation of 1,2-dichlorobenzene ( o -DCB) was studied over Pd/Co-HMOR and Pd/Co-SZ catalysts under lean, dry and wet conditions. Catalysts were characterized by XRD, BET, TGA, H 2 -TPR, NH 3 -TPD, TEM/EDS and Raman spectroscopy. Pd/Co-HMOR showed better catalytic performance than Pd/Co-SZ in terms of activity and durability under both dry and wet conditions at 500 °C. The presence of Co 2+ ion in both catalysts explains partially the high activity towards o -DCB oxidation. The deactivation of Pd/Co-HMOR for CH 4 -SCR at reaction temperatures above 500 °C may be related with the formation of PdO specie while the loose of sulfate groups of Pd/Co-SZ can be correlated with the deactivation of this catalyst towards CH 4 -SCR. According to NH 3 -TPD analysis, both Pd/Co-HMOR and Pd/Co-SZ catalysts present strong acid sites in the temperature range from 300 to 600 °C, which can be associated with their considerable active towards both reactions. The higher performance of Pd/Co-HMOR compared with Pd/Co-SZ, mainly in the CH 4 -SCR reaction, can be related with the higher total acidity of the catalyst supported on HMOR. The XRD analysis of used samples showed that Pd/Co-HMOR losses crystallinity at reaction temperatures greater than 500 °C and that monoclinic phase appears in Pd/Co-SZ owing to sulfate group loss. [ABSTRACT FROM AUTHOR]

The current environmental legislations recommend monitoring chemical contaminants such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans before the use of sewage sludge on the agricultural land. In this study, a solid-liquid extraction with low-temperature purification (SLE-LTP) was optimized and validated to determine 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8- tetrachlorodibenzofuran in sewage sludge and soil samples. The analyses were performed by gas chromatography-mass spectrometry operating in the selective ion mode (GC-MS-SIM). Acetonitrile:ethyl acetate 6.5:1.5 (v/v) was the best extraction phase, and the recoveries percentages were close to 100%. The linearity was demonstrated in the range of 1.25-25 μg L-1 of 1.25-20 μg L-1 for sewage sludge and soil, respectively. Matrix effect was proved for the two compounds and in the two matrices studied. Extraction percentages were between 78 and 109% and relative standard deviations ≥ 19%. The proposed method is faster than methods described in the literature because showed a few steps. The quantification limits (LOQ) in sewage sludge were 6.4 and 32 ng TEQ kg-1 for 2,3,7,8-TCDF and 2,3,7,8-TCDD, respectively. In soil, LOQs were 0.8 and 8.0 ng TEQ kg-1 for 2,3,7,8-TCDF and 2,3,7,8-TCDD, respectively. These values are lower than the maximum residue limits established by European Legislation. The method was applied to 22 agricultural soil samples from different Brazilian cities and 2,3,7,8-TCDF was detected in one of these samples. [ABSTRACT FROM AUTHOR]

Multi-year (1999–2014) vehicular unregulated pollutants emissions in China, including SO 2 , CH 4 , N 2 O, NH 3 , Indeno(1,2,3- cd )pyrene (IPY), Benzo( k )fluoranthene (BkF), Benzo( b )fluoranthene (BbF), Benzo( a )pyrene (BaP), dioxins and furans, were estimated based on emission factors calculated by COPERT. The inter-annual trends, correlation with GDP and population, spatial distribution characteristics, contributions from various vehicle types for the ten pollutants emissions were analyzed. Results showed that the emissions of the above ten pollutants changed from approximately 576.9 Gg, 130.0 Gg, 8.1 Gg, 2.1 Gg, 1.0 Mg, 1.1 Mg, 1.4 Mg, 0.5 Mg, 7.4 g and 15.6 g in 1999 to 193.8 Gg, 171.1 Gg, 79.1 Gg, 117.8 Gg, 3.5 Mg, 6.7 Mg, 6.8 Mg, 2.9 Mg, 37.6 g and 79.1 g in 2014, respectively. Implementation of stringent sulfur content limit during the past decade reduced approximately 94.4% of the SO 2 emission in 2014. CH 4 and N 2 O increased from 1999 to 2011, but began to decrease since 2012; NH 3 emission had the highest annual average change rate (35.5%) from 1999 to 2014; PAHs, dioxins and furans increased continuously during the past decade. The vehicular emissions were higher in Guangdong, Shandong, Henan, Jiangsu, Zhejiang and Hebei. Good linear correlation between vehicular emissions and GDP was found (except SO 2 ); in the provinces/municipalities with higher population density, the emission density was also larger, indicating more significant vehicular emissions' potential damage on human health. HDT and PC, PC and MC, PC and BUS were the major contributors to SO 2 , CH 4 , N 2 O emissions, respectively. In 2014, PC was the dominant contributor to NH 3 emission; PC, BUS and HDT had higher fraction in the total IPY and BaP emissions; HDT was the major contributor to BkF and BbF emissions. In addition, the uncertainties of estimated emissions were also analyzed based on Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Tree swallows, Tachycineta bicolor, were sampled across the Great Lakes basin in 2010 through 2015 to provide a systemwide assessment of current exposure to organic contaminants. The results provide information identified as critical by regulators to assess the "bird or animal deformity or reproductive problems" beneficial use impairment. Eggs were collected from 69 sites across all 5 Great Lakes, including 27 Areas of Concern (AOCs), some with multiple sites, and 10 sites not listed as an AOC. Concentrations of organic contaminants in eggs were quantified and compared with background and reproductive effect thresholds. Approximately 30% of AOCs had geometric mean concentrations of total polychlorinated biphenyls (PCBs) at or below average background exposure (0.34mg/g wet wt). Exposure to polybrominated diphenyl ethers (PBDEs) was minimal, and only 3 of 27 AOCs and 1 non-AOC had geometric mean concentrations that exceeded background for tree swallows (96 ng/g wet wt). Concentrations of both PCBs and PBDEs were 10 to 20 times below the lower limit associated with impaired hatching success. In contrast, geometric mean concentrations of polychlorinated dibenzo-p-dioxin and furan (PCDD-F) toxic equivalents (TEQs) at the Saginaw River and Bay AOC and Midland, Michigan, USA (a non-AOC site), exceeded the lower limit for hatching effects (181 pg/g PCDD-F TEQs). The rest of the sites had geometric mean concentrations of PCDD-F TEQs below background levels (87 pg/g PCDD-F TEQs). Other organic contaminants, including p,p0-dichlorodiphenyldichloroethylene, mirex, heptachlor, and chlordane, were at or below background or adverse effect concentrations. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans are generally considered the most dangerous chemical substances known to man. Although they have never been the product of purposeful human activity, yet they are formed in many chemical and virtually all thermal processes. Research on the occurrence of dioxins in the environment, their release into the environment, ways of formation and methods of reducing their emissions lasts since the late seventies of the last century. Currently, we know three basic pathways of dioxins formation in thermal processes, the most important of them being the so called de novo synthesis which occurs outside the combustion zone at 200-400°C in the presence of catalysts ( eg copper) and oxygen from the products of incomplete combustion including carbon black and chlorine or chlorinated compounds. It is well known that some metals like copper catalyze the de novo synthesis, while others decompose dioxins and furans formed previously. The formation of dioxins resulting from the de novo synthesis was studied through analysis of the effect of the type of metal on the course of the de novo synthesis. The influence of the addition of sulfur, nitrogen and alkali metals on this synthesis was also examined because some reports in the literature refer to inhibitory effect of these elements. [ABSTRACT FROM AUTHOR]

The product gas produced from gasification of solid fuel contains various impurities such as particulates, toxin gases, tar, vapours of heavy metals, etc. Presence of tar is a major issue which requires to be addressed before the use of gas product in the downstream process. Tar causes problems in the process equipment like flow channels, power generating units, etc. Generally gasification technology is adapted for the utilization of low grade coal, municipal solid waste, agro-waste, bio-waste, etc., which generates toxic and emits various hazardous compounds of chlorine, sulphur, nitrogen and heavy metals like Mn, Cd and Hg. Various alkali metals like Na, K, etc., generated through the gasification of wastes also create problem in the downstream processes when condensed at low temperature. The key challenge to commercializing gasification technology is to generate a clean fuel gas which meets the global emission standards. This paper provides a comprehensive overview of the fuel gas cleaning methods those are used to remove the contaminants and gas impurities generated from various types of reactor for gasification of coal or biomass. [ABSTRACT FROM AUTHOR]

Lichens are one of the most useful environmental biomonitors, due to their ability to clearly reflect atmospheric deposition of pollutants. Dioxin and furan (PCDD/F) emissions have been reported to be decreasing in North European countries as a consequence of European regulations. This reduction has been perceptible across several environmental matrices, but it hasn't yet been shown in lichens as typical biomonitors of atmospheric pollution. In this work we compared concentrations of PCDD/Fs in two lichen species collected in a Mediterranean area with mixed land-uses, encompassing urban, industrial and natural areas, in 2009 and 2011 with the ones obtained in the same species collected in the same region in 2000. We found that PCDD/F concentrations in both lichen species have decreased approximately 70% since 2000 whereas industrial emissions have only decreased 25% for the same period. This substantial greater reduction observed in lichens may be due to several causes; after excluding fires as a possible explanation, we point out that possible causes could not only be the overall decrease in industrial emissions but also other causes such as traffic reduction and/or increase efficiency in the use of fuels. Capsule: PCDD/F concentrations in lichens have decreased 70% over the last decade, whereas industrial emissions have only decreased 25%. [ABSTRACT FROM AUTHOR]

A series of flat panel television burns were performed with incrementally increasing ignition sources in a single burning item apparatus. A comparison study was performed of like model televisions for the United States, Mexican and Brazilian markets. Heat release rate, smoke, combustion gas, TO-15 vapor, and halo-dioxin and furan generation were measured. A total of 18 televisions were ignited and their burning behavior studied to examine the impact of materials of construction and the presence of fire retardants in the casing of the televisions on fire growth. US market televisions required more than 500 W with greater than 180 s exposure to ignite and in four out of the 6 trials these televisions did not achieve sustained ignition. In the two cases where sustained ignition for the US market televisions occurred, it was not the flat panel display television itself which ignited, but the stand and mounting bracket which lead to fire growth. Mexican and Brazilian market televisions ignited easily with 60 s exposure to a 50 W flame. US market televisions did produce brominated dioxins or furans but the mass loss of these televisions was much lower. [ABSTRACT FROM AUTHOR]

A selective pressurized liquid extraction technique (SPLE) was developed for the analysis of polychlorodibenzo- p-dioxins, polychlorodibenzofurans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) in clam and crab tissue. The SPLE incorporated multiple cleanup adsorbents (alumina, florisil, silica gel, celite, and carbopack) within the extraction cell. Tissue extracts were analyzed by high resolution gas chromatography coupled with electron capture negative ionization mass spectrometry. Mean recovery (n = 3) and percent relative standard deviation for PCDD/Fs and dl-PCBs in clam and crabs was 89 ± 2.3 and 85 ± 4.0, respectively. The SPLE method was applied to clams and crabs collected from the San Jacinto River Waste Pits, a Superfund site in Houston, TX. The dl-PCBs concentrations in clams and crabs ranged from 50 to 2,450 and 5 to 800 ng/g ww, respectively. Sample preparation time and solvents were reduced by 92 % and 65 %, respectively, as compared to USEPA method 1613. [ABSTRACT FROM AUTHOR]

In this paper, flotation in acidic conditions and alkaline leaching soil washing processes were compared to decontaminate four soils with variable contamination with metals, pentachlorophenol (PCP), and polychlorodibenzo dioxins and furans (PCDD/F). The measured concentrations of the four soils prior treatment were between 50 and 250 mg/kg for As, 35 and 220 mg/kg for Cr, 80 and 350 mg/kg for Cu, and 2.5 and 30 mg/kg for PCP. PCDD/F concentrations reached 1394, 1375, 3730, and 6289 ng/kg for F1, S1, S2, and S3 soils, respectively. The tests were carried out with masses of 100 g of soil (fraction 0–2 mm) in a 2 L beaker or in a 1 L flotation cell. Soil flotation in sulphuric acid for 1 h at 60°C with three flotation cycles using the surfactant cocamidopropyl betaine (BW) at 1% allows the solubilization of metals and PCP with average removal yields of 85%, 51%, 90%, and 62% for As, Cr, Cu, and PCP, respectively. The alkaline leaching for 2 h at 80°C solubilizes As, Cr, Cu, and PCP with average removal yields of 60%, 32%, 77%, and 87%, respectively. Tests on PCDD/F solubilization with different surfactants were carried out in combination with the alkaline leaching process. PCDD/F removal yields of 25%, 72%, 70%, and 74% for F1, S1, S2, and S3 soils, respectively, were obtained using the optimized conditions. [ABSTRACT FROM PUBLISHER]

This paper deals with the efficiency of the processes in alternative gas fuels production based on the conversion of biomass and carbonaceous waste using plasma technology. The properties of certain types of these raw materials—wood, medical and municipal solid waste, poultry and livestock waste as well as corn waste—are analyzed from the view point of gasification technologies. It is shown that the processing of certain types of waste involves environmental hazard. The equipment for hazardous waste disposal is briefly presented. The modes of their operation are chosen in view of the requirements associated with the exception of toxicants, tar formation, and sooting. In addition, the conditions of nitric oxide and dioxide formation are analyzed on the basis of kinetic treatment in the case of using air plasma. It is shown that the plasma steam technology has higher energy efficiency characteristics in comparison with steam-oxygen. [ABSTRACT FROM PUBLISHER]

Abstract: Dioxins and Furans are generated unintentionally during incineration of halogenated hazardous waste which warrants adequate pollution control measures. International Agency for Research in Cancer(IARC) reported that population exposed to the most highly carcinogen 2,3,7,8-TCDD (one of the congener of dioxin) is more prone to increased risk of cancer, beyond this, societal risks are enhanced to people living in nearby areas even if they are not exposed directly. The study compares societal costs of dioxin & furan emission with events such as water borne diseases, rail and road accidents etc. The basic approach is adopted to convert impact of various risks into reduction in life span of the total population to form a common basis for comparison. This paper find out the “break even” standard for dioxin and furan emission where emission control costs and societal costs are equal. This is an attempt to develop a conceptual approach to consider societal cost as one of the determinants for developing emission standard in future. The reason is that the break even number 0.15 ng TEQ/Nm3 should not be taken as sacrosanct since studies are based on a variety of assumptions. [Copyright &y& Elsevier]

The history of the Venice Lagoon contamination is presented here, based on sediment records and on information about industrial activities and past management choices. We used polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as tracers since the relative abundance of their congeners can help in locating their sources. The most important PCDD/F source to the canals of the first industrial area (built in the 1920s) can be ascribed to processes involving pyrite to obtain sulfuric acid and recovery of copper and other metals. Indeed, homologue profiles and documents show that the PCDD/Fs contamination is mainly related to the use and disposal of both these industrial wastes and materials dredged from the most contaminated canals. In particular, these latter constitute the ground under the second industrial area (built after World War II). Furthermore, hazardous materials were stored until 1992 in an islet exposed to erosion, whereas tracts of industrial canal banks eroded until 2000. Similar situations are frequent in transition and coastal areas worldwide. [ABSTRACT FROM AUTHOR]

Abstract: The concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were determined in a number of foodstuffs purchased in various locations near a hazardous waste incinerator (HWI) in Tarragona County (Catalonia, Spain). The dietary intake of PCDD/Fs by the population of the area under potential influence of the HWI was subsequently estimated. The results were compared with previous surveys performed in the same area in 1998 (baseline), 2002 and 2006. In the present study, the highest WHO-TEQ corresponded to industrial bakery (0.183ng/kg wet weight, ww), followed by fish (0.156ng/kg ww), oils and fats (0.112ng/kg fat weight), and seafood (0.065ng/kg ww). In contrast, the lowest values were observed in pulses and tubers (0.003ng/kg ww), and cereals and fruits (0.004ng/kg ww). The dietary intake of PCDD/Fs by the general population was 33.1pg WHO-TEQ/day, having fish and seafood (11.6pg WHO-TEQ), oils and fats (4.61pg WHO-TEQ), dairy products (3.79pg WHO-TEQ), and industrial bakery (3.49pg WHO-TEQ) as the groups showing the highest contribution to the total TEQ. The lowest daily contributions corresponded to pulses (0.08pg WHO-TEQ) and tubers (0.25pg WHO-TEQ). This intake was considerably lower than that found in the baseline study, 210.1pgI-TEQ/day, and also notably lower than that found in the 2002 survey (59.6pgI-TEQ/day), but slightly higher than the intake estimated in the 2006 survey, 27.8pgWHO-TEQ/day. The results of this study show that any increase potentially found in the biological monitoring of the general population living in the area under evaluation should not be attributed to dietary exposure to PCDD/Fs. [Copyright &y& Elsevier]

Abstract: Health risk assessment due to the atmospheric emissions of carcinogenic pollutants (PCDD/Fs and Cd) from a waste gasification plant is performed by means of a probabilistic approach based on probability density functions for the description of the input data of the model parameters involved in the assessment. These functions incorporate both the epistemic and stochastic uncertainty of the input data (namely, the emission rate of the pollutants) and of all the parameters used for individual exposure assessment through the pathways of inhalation, soil ingestion and dermal contact, and diet. The uncertainty is propagated throughout the evaluation by Monte Carlo technique, resulting in the probability distribution of the individual risk. The median risk levels nearby the plant are in the 10-8–10-10 range, ten-fold lower than the deterministic estimate based on precautionary values for the input data; however, the very upper percentiles (>95th) of the risk distribution can exceed the conventional 10-6 reference value. The estimated risk is almost entirely determined by the Cd exposure through the diet; the pathways arising from PCDD/Fs exposure are without any practical significance, suggesting that the emission control should focus on Cd in order to reduce the carcinogenic risk. Risk variance decomposition shows the prevailing influence on the estimated risk of the Cd concentration at the emission stack: thus, for a more accurate risk assessment the efforts should focus primarily on the definition of its probability density function. [Copyright &y& Elsevier]

Abstract: A high-throughput enhanced pressurized liquid extraction technique was developed by incorporating pressurized liquid extraction and multiple cleanup techniques. USEPA methods of polychlorodibenzo-p-dioxins, polychlorodibenzofurans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) analysis in fish tissue include independent silica gel, florisil, alumina, and carbopack/celite column cleanup techniques following extraction. Under the improved method, fish composites (∼10g) were extracted and cleaned simultaneously using alumina (∼10g), florisil (∼10g), silica gel (∼5g), celite (∼5g), and carbopack (∼0.5g). Clean extracts were concentrated and then analyzed by high resolution gas chromatography coupled with electron capture negative ionization mass spectrometry. Carbopack/celite within the extraction cell provided the analytical separation of dl-PCBs from PCDD/Fs, reducing potential molecular interferences. The average recoveries (n =3) of dl-PCBs in dichloromethane:hexane (1:1, v/v) extracts were 93±2.4% and PCDD/Fs in toluene extracts were 85±3.0%. The developed method was applied to measure the PCDD/Fs and dl-PCBs in catfish from San Jacinto River Waste Pits, a Superfund site in Houston, TX. The dl-PCBs were measured at 5.0–17,000pgg−1 ww. Sample preparation time and solvents were reduced as much as 95% and 65%, respectively, as compared to USEPA method 1613. [Copyright &y& Elsevier]

Concentrations of polychlorinated dibenzofurans (PCDFs) and other dioxin-like compounds in soils and sediments of the Tittabawassee River and associated floodplains downstream of Midland, Michigan, USA, are greater than upstream sites. As a result of these concentrations, which are some of the greatest ever reported, a site-specific exposure assessment of belted kingfisher breeding in the assessment area was conducted. To reduce the uncertainty associated with predicting exposure from abiotic matrices, concentrations of residues were quantified in site-specific prey items and in eggs and nestlings of belted kingfisher. Dietary exposure, expressed as the potential average daily dose, based on site-specific concentrations of PCDFs, polychlorinated dibenzo- p-dioxins (PCDDs), and 2,3,7,8-tetrachlorodibenzo- p-dioxin equivalents (TEQWHO-Avian) in prey items was consistently greater along the Tittabawassee River than in associated reference areas and further downstream sites in the Saginaw River. Concentrations of PCDD/DFs in eggs and nestlings of belted kingfisher varied among sampling areas, being greater in both eggs and nestlings nesting along the Tittabawassee River compared to those of belted kingfisher from upstream reference areas. Geometric mean concentrations of PCDD/DFs were 130 and 200 ng/kg wet weight in eggs and nestlings of belted kingfisher, respectively. These concentrations are the equivalent of 84 and 95 ng TEQWHO-Avian/kg. Site-specific biomagnification factors for select PCDD/DF congeners ranged from <1.0 to 1.8 in belted kingfisher. Environ. Toxicol. Chem. 2012; 31: 1158-1168. © 2012 SETAC [ABSTRACT FROM AUTHOR]

Abstract: In recent years, the cremation ratio of cadavers has increased dramatically in many countries. Crematories have been identified as sources of various environmental pollutants, being polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and mercury those raising most concern. In contrast to other incineration processes for which the number of studies on their toxic emissions is considerable, references related to PCDD/F and mercury emissions from crematories and their health risks are very limited. In this paper, the scientific information concerning these issues, using the databases PubMed, Scopus and Scirus, is reviewed. Results show that in comparison with PCDD/F emissions from other sources, those corresponding to crematories are significantly lower, while those of mercury should not be underrated. [Copyright &y& Elsevier]

Abstract: Most fly ashes produced in municipal waste incinerators of Catalonia (Spain) are deposited in a hazardous waste landfill (HWL) placed in Castellolí (Barcelona). This facility means a concern for the population living nearby. In response to this, we performed a probabilistic study focused on assessing human health risks derived from environmental exposure to heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) around the HWL. Concentrations of various metals and PCDD/Fs were determined in soil and air samples collected at the HWL, and in 4 locations around it. Health risks were evaluated according to the distance from the sampling locations to the HWL (near and far-sites). In general terms, metal and PCCD/F levels were relatively low in air and soil samples. However, concentrations of PCDD/Fs, as well as those of some metals, were found to be relatively higher in the HWL and Castellolí (the nearest village) samples than in those collected far away, resulting in a slight increase of exposure to those pollutants. Anyhow, the current concentrations of metals and PCDD/Fs suggest that it is highly unlikely that there are any additional non-carcinogenic and carcinogenic risks for the population living near the HWL. [Copyright &y& Elsevier]

Abstract: Toxic Equivalency Factors (TEFs) are an essential part of the Toxic Equivalent (TEQ) concept and have evolved for dioxins/dioxin-like compounds over the last two and half decades. Therefore, it is difficult to compare past and current TEQs that are reported using different TEFs without explicitly mentioning underlying congener concentrations. Using what likely is the largest known dioxin/furan (PCDD/F) and dioxin-like polychlorinated biphenyl (dl-PCB or DLP) fish database, here we present regression models that can facilitate conversion of a fish TEQ from an old to a newer TEF scheme. The results show that the mammalian PCDD/F-TEQ based on the latest TEFWHO-05 is about 7.5% lower than that based on TEFWHO-98. The mammalian DLP-TEQWHO-05 is on average 25-26% lower than almost identical DLP-TEQWHO-94 and DLP-TEQWHO-98. Total-TEQWHO-05 is on average 22% lower than Total-TEQWHO-98. According to the current toxicological standards for dioxins/furans, all previous major TEF schemes except TEFGermany-85 and TEFUSEPA-87 were conservative (i.e., higher) in estimating TEQs. The major (>75%) contribution to PCDD/F-TEQWHO-05 is from 2,3,7,8-TCDD (33%), 1,2,3,7,8-PCDD (26%), 2,3,7,8-TCDF (10%), and 2,3,4,7,8-PCDF (9%). The DLP-TEQWHO-05 is dominated by PCB-126 which on average contributes about 88%. The DLP-TEQ generally contribute >70% of Total-TEQ. When reporting TEQs, we recommend that the underlying congener specific concentrations are presented, TEF scheme used is clearly stated, names of compounds included are explicitly expressed, and TEQs are identified accordingly (e.g., DLP-TEQ, PCDD/F-TEQ, Total-TEQ). [Copyright &y& Elsevier]

Background data of polychlorinated dibenzodioxin and dibenzofuran (PCDD/Fs) emissions from the incineration sector in Colombia are presented. Monitoring was carried out during a two-year period, 2003–2005. Twelve plants were sampled for stack gas emissions of dioxins and total solid particulate (TSP). Additionally, PCDD/Fs in several fly ash samples were analyzed. Most incinerators burned industrial refuse materials and medical residues. A wide range of PCDD/Fs emission levels were found. In particular, levels ranging from 6.9 to 343.8ng I-TEQ/Nm3 were determined in plants without any air pollution control system (APCS). In contrast, 0.5–39.2ng I-TEQ/Nm3 levels were found in plants with APCS while 8.5–67.5ng I-TEQ/g were measured in fly ash samples. TSP values ranged from 14 to 448mg/Nm3. This study also evaluated the impact of implementing different control systems in an incinerator. Finally, for comparison purposes several samples were analyzed by both high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC-HRMS) and high resolution gas chromatography coupled to ion-trap low resolution mass spectrometry–mass spectrometry (HRGC-IT LRMS/MS). Overall, I-TEQ values deviated about 20–30% between both techniques. [Copyright &y& Elsevier]

Abstract: The use of sophisticated air pollution modeling systems to evaluate the impact of different industrial plant emissions is currently done in an extensive way. MM5-CMAQ (PSU/NCAR and EPA, USA) is one of the most applicable air quality modeling systems to evaluate those impacts. In this contribution we present the methodology and results obtained when applying the MM5-CMAQ air quality modeling system for evaluating the potential impact of an incinerator in San Sebastián (Basque Country, Spain). We have used the EMIMO (UPM, Spain) emission model to simulate the emissions from biogenic and anthropogenic sources including traffic and tertiary sector sources. The study includes the air quality impact of a highway located near the incinerator named A8 and 6 industrial plants which already exist. The impact study has been compared with the results obtained from this highway impact and the 6 industrial plants which are normally operating during the last 30 years. The system has been prepared to simulate also Cadmium, Arsenic, Nickel, Lead and Benzo(a)pyrene air quality impacts. The PCDD/F air concentrations have been determined for the 16 toxic dioxins and furans as determined in the bibliography. The criteria pollutants such as CO, NOx, SO2, PM10 and O3 have also been determined according to the different EU Directives which limit the values of such a pollutants for different periods of time. [Copyright &y& Elsevier]

The levels of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were measured in foodstuffs randomly acquired in July 2006 in various locations of Tarragona County (Catalonia, Spain), which are near a hazardous waste incinerator (HWI). A total of 35 composite samples, belonging to various food groups (vegetables, pulses, cereals, fruits, fish and seafood, meat and meat products, eggs, milk, dairy products, and oils and fats) were analyzed by HRGC/HRMS. The dietary intake of PCDD/PCDFs was subsequently determined and compared with a previous survey performed in 2002. For calculations, recent data on consumption of the selected food items were used. Total dietary intake of PCDD/PCDFs for the general population of Tarragona County was estimated to be 27.81pg WHO-TEQ/day, value notably lower than that found in the 2002 study, 63.80pg WHO-TEQ/day. Fish and seafood (28%), oils and fats (22%), eggs (17%), and dairy products (11%) were the most important contributors to this intake, while pulses (1%), milk (2%), vegetables (3%) and fruits (3%) showed the lowest contribution to total WHO-TEQ. The current PCDD/PCDF intake is also considerably lower than the intake estimated in 1998 for the population of the same geographical area, 210.1pg I-TEQ/day, when a baseline study was carried out during the construction of the HWI. The present intake is also compared with the dietary intakes of PCDD/PCDFs recently (2006–2007) reported for a number of regions and countries. [Copyright &y& Elsevier]

Rapid economic growth in the last two decades in Shanghai has had a great adverse influence on its air quality. Therefore, the atmospheric pollutants of Shanghai have received much concern. In this study, concentrations of 2,3,7,8-substituted PCDD/Fs and PBDD/Fs congeners were measured in the ambient air of four districts in Shanghai. The mean atmospheric concentrations (TEQs) of total 2,3,7,8-PCDD/Fs and 2,3,7,8-PBDD/Fs were 8031fgm−3 (497.1fgI-TEQm−3) and 1358fgm−3 (304.1fgI-TEQm−3) for Jiading District, 5308fgm−3 (289.0fgI-TEQm−3) and 709fgm−3 (146.9fgI-TEQm−3) for Zhabei District, 4014fgm−3 (144.4fgI-TEQm−3) and 1239fgm−3 (256.9fgI-TEQm−3) for Pudong District, 3348fgm−3 (143.2fgI-TEQm−3) and 699fgm−3 (148.4fgI-TEQm−3) for Huangpu District, respectively. Our results showed that almost all the PCDD/Fs and PBDD/Fs congeners were partitioned into the particulate phase except the lower chlorinated or brominated ones. The logarithm of the gas/particle partitioning coefficient K p has good linear correlation with that of the sub-cooled vapor pressure p L. Concentrations of PCDD/Fs and PBDD/Fs were both positively correlated to elemental carbon in all districts except Pudong District, suggesting elemental carbon could be a good indicator for dioxins’ air pollution. It is intensively suggested that more detailed and deeper studies about PBDD/Fs should be carried out due to their relatively high atmospheric concentrations in Shanghai. [Copyright &y& Elsevier]

Abstract: Since 1971, a municipal solid waste incinerator (MSWI) with high dioxin emission levels has been in operation in Besançon, France. We recently found a 2.3-fold risk of non-Hodgkin’s lymphoma in the highest exposure zone using a Gaussian-type dispersion model as a proxy for dioxin exposure. However, the sources of PCDD/Fs in this area are a matter of controversy. The aim of this survey was therefore to examine the nature of the PCDD/F soil contamination in the surroundings of the MSWI to characterize whether more than one potential emission source could explain the presence of the PCDD/Fs. PCDD/F congener profiles were determined in 75 soil samples collected in the vicinity of the MSWI. They were compared according to the most environmentally impacted zones and to various spatial contrasts. PCDD/F concentrations ranged from 0.25 to 28.06pg WHO–TEQg−1. Two different clustering algorithms identified the same main cluster (consisting of 73 samples). The remaining two soil samples composed either one, or two clusters. All clusters showed similar congener profiles. Moreover, no contrast was observed for congener distributions between complex and simple topographies, inside and outside the city boundary, the two most and the two least exposed areas, reflecting a common fingerprint. Congener profiles indicate that the area under influence of the MSWI is not subject to other point sources of PCDD/Fs. Since, the most polluting combustion chambers were recently shut down and replaced by a new one with up-to-date pollution control, slowly decreasing dioxin concentrations in the soils are to be expected. [Copyright &y& Elsevier]

Dioxins and furans (PCDD/Fs), polychlorobiphenyls (PCBs) and hexachlorobenzene (HCB) in the ecosystem of the Lagoon of Venice were studied, in order to provide a general picture of conditions in the lagoon in terms of contamination by persistent organic pollutants (POPs). We present here novel data on atmospheric deposition, water, sediment and clam samples collected in the lagoon during the period January 2001–December 2004. Atmospheric deposition was sampled monthly at six sites located both close and far from large industrial and urban sources. Water samples were collected monthly from fifteen stations, and twenty-five samples of sediments and clams (Tapes philippinarum) were collected in four areas where clams are farmed and harvested inside the lagoon. All samples were analysed for PCDD/Fs, PCBs and HCB by HRGC/HRMS in the same laboratory. All samples examined (atmospheric deposition and water) substantially confirmed the spatial pattern reported in previously published data on sediments and atmospheric deposition: the zone surrounding the Porto Marghera petrochemical plant always had the highest levels of POPs (i.e., PCDD/Fs: atmosphere ∼6pg of 2,3,7,8-TCDD equivalents (I-TE) m−2 d−1; water 0.37pgI-TEl−1; sediment: 300ngkg−1; clam 2.8pg I-TE g−1), and the minima were found at points on the margins of the lagoon (PCDD/Fs: atmosphere ∼1pgI-TEm−2 d−1; water 0.05pgI-TEl−1; sediment: ∼5ngkg−1; clam ∼0.2pg I-TE g−1). Intermediate values were often encountered in the historical city centre of Venice and in the central part of the lagoon. To confirm this, new data on correlation between levels of PCDD/F in sediments and clams are reported, both for absolute values and for the PCDD/F “fingerprint”. There is always a clear fingerprinting signature (PCDF/PCDD>1) for samples collected near Porto Marghera, and the opposite (PCDF/PCDD<1) in the rest of the lagoon. [Copyright &y& Elsevier]

This paper reports the main results of a project to establish a Colombian inventory of dioxin and furan release vectors and sources during 2002. The project followed the methodology proposed by the United Nations Environment Program (UNEP) in the ‘Standardized Toolkit for Identification and Quantification of Dioxin and Furan Releases’, Toolkit, first issued in May 2003. The country specific, dioxin and furan emitting sources were identified, according to the sources stated in the guide material and their releases were quantified from the information gathered for each one of the processes and using default emission factors proposed in the Toolkit. The total emissions were, 945.42 g TEQ/a (grams of toxic equivalent per year). The main sources are uncontrolled combustion estimated as 46.06% of the total emissions and waste incineration as 30.05%. The most important emissions vectors are air at 52.07% and residues at 39.43% of total. Some limitations were encountered in data gathering. There are no official records for some of the subcategories that are intended to be taken into account. The per capita emission rate in Colombia is relatively low, compared to other countries with similar levels of industrial development. [ABSTRACT FROM AUTHOR]

Abstract: From 1975 to 2004, a municipal solid waste incinerator (MSWI) was operating in Montcada (Barcelona, Catalonia, Spain). Because of the potential health risks derived from emission of pollutants by the facility, especially polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), a long-term monitoring program focused on measuring the environmental levels of PCDD/Fs near the facility, and to assess the health risks for the population living in the neighborhood, was established between 1996 and 2002. A total number of 111 soil and 121 herbage samples were analyzed for PCDD/Fs during this period. Human health risks for the individuals living near the MSWI (500 and 1000 m) were also assessed before (1998) and after modernization (2000) of the facility. It included PCDD/F inhalation, dermal contact, soil and dust ingestion, and food intake. All these data are here summarized. The environmental levels of PCDD/Fs showed that the MSWI was not the main responsible of the atmospheric pollution by these compounds. In turn, human health risks for the population living in the vicinity of the facility after introduction of a modern technology were negligible in comparison with the dietary PCDD/F exposure. [Copyright &y& Elsevier]

Abstract: The thermal oxidation of 2-chlorophenol (2-CP) in air was investigated using a perfectly stirred reactor at 1atm over the temperature range 450–900°C. The relative concentration of 2-CP was 1000ppmV (equivalence ratio Φ =0.03). About fifty organic products were identified as trace species. The concentration profiles of 2-CP, carbon oxides as well as those of seventeen major organic intermediates and six non-to-lower chlorinated dioxins and furans were presented as a function of temperature for a residence time of 2s. The most abundant intermediate products were carbon monoxide, 2H-pyran-2-one, chlorobenzene, 4-cyclopenten-1,3-dione, phenol, benzofuran, 2-chlorohydroquinone and 2-indanone. These concentration profiles have revealed that temperatures of at least 900°C were needed to completely oxidize 2-CP, CO and all other organic byproducts to carbon dioxide. Reaction pathways accounting for the formation of most observed products are proposed. [Copyright &y& Elsevier]

Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in slag of fly ash from three municipal solid waste (MSW) incinerators were analyzed to observe any changes in characteristics and distribution of their congeners by melting process. Actual concentration and Toxic Equivalent (TEQ) concentration profiles of 17 major congeners of PCDDs/PCDFs for gas, fly ash and melted slag were compared. The distributions of PCDDs/PCDFs in different streams macroscopically showed similarities with the generally known profiles for emission gas from a municipal waste incinerator. The total concentrations of PCDDs/PCDFs in off-gas and fly ash have been known to be a function of incineration conditions and of air pollution control device utilization; however, their normalized distributions were independent of such conditions. The concentrations of PCDDs/PCDFs in the melted slag of fly ash were not related to the concentrations of PCDDs/PCDFs congeners in fly ash but were rather a function of the melting furnace type and operation. The total amount of PCDDs/PCDFs in the melted slag of fly ash contained almost 150–27,000 times less dioxin than that in fly ash, however, the TEQ of dioxin in the slag was reduced by 435–43,500 times, which could enable them to be utilized as recycled construction materials. In normalized TEQ concentration profiles of 17 congeners of PCDDs/PCDFs, the ratio of PCDFs to PCDDs changed from 1.32 to 2.19 by melting, which showed relatively higher portion of furans left in melted slag than those in fly ash. By comparing reduction ratios of different congeners, PCDDs (dioxins) were relatively easier to destruct than PCDFs (furans) during melting process. The most difficult congener to destruct could be octa-chlorinated dibenzofuran (OCDF) among major congeners. For slag cooling methods, dioxin concentration in TEQ of slow cooled slag by air was four times higher than that of fast cooled slag by water. Thus cooling by water is more appropriate with the added beneficial effect of producing granules/particles, which can be utilized as roadbed materials. [Copyright &y& Elsevier]

Concentrations of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were measured in foodstuffs randomly acquired in various locations of Tarragona County (Catalonia, Spain) in September 2002. A total of 36 composite samples, belonging to various food groups (vegetables, fruits, meat and meat products, fish and seafood, cereals, pulses, milk, dairy products, eggs, and oils and fats) were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry. The dietary intake of PCDD/Fs was subsequently determined. For calculations, recent data on consumption of the selected food items were used. Total dietary intake of PCDD/Fs for the general population of Tarragona County was estimated to be 59.6 pg I-TEQ/day (63.8 pg WHO-TEQ/day). Fish and seafood (33.7%), oils and fats (15.3%), cereals (14.4%), and dairy products (13.7%) were the most important contributors to this intake. This PCDD/F intake is notably lower than the intake estimated in 1998 for the same geographical area, 210.1 pg I-TEQ/day. The current PCDD/F dietary intake is below the tolerable intake range of 1–4 pg TEQ/kg body weight/day established by the WHO in 1998. Finally, the current intake is compared with the dietary intakes of PCDD/Fs recently (2001–2003) reported for a number of regions and countries. [Copyright &y& Elsevier]

To assess the influence of a new hazardous waste incinerator (HWI) on public health, a preoperational monitoring program was established during the period of construction. In this study, the levels of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) accumulated in adipose tissue of 15 autopsied subjects living in the area under potential impact of the HWI were determined after approximately 3 years of regular operations in the facility. The non-ortho PCBs 77, 126 and 169 were also determined. PCDD/F concentrations ranged between 1.5 and 41 pg WHO-TEQ/g fat (2.4 and 72 WHO-TEQ/g fat, respectively, including PCBs), with a mean value of 11 pg WHO-TEQ/g fat and a median value of 7.4 pg WHO-TEQ/g fat (22 and 13 WHO-TEQ/g fat, respectively, including PCBs). In the baseline study, the mean level of PCDD/Fs was 36 pg WHO-TEQ/g fat (61 pg WHO-TEQ/g fat, including non-ortho PCBs 77, 126 and 169), which means a reduction of 70% (64% including PCBs). This notable reduction is in accordance with the important decrease observed in recent years in PCDD/F intake through the diet. The current concentrations of PCDD/Fs in human adipose tissue, as well as recent data on PCDD/F levels in plasma and breast milk of subjects living in the vicinity of the same HWI, indicate that there is not any additional significant exposure to PCDD/Fs for this population. [Copyright &y& Elsevier]

The aim of this study was to calculate the incremental lifetime-risk to dioxins and furans (PCDD/Fs) for the population living in the surroundings of a municipal solid waste incinerator (MSWI), as well as to establish the potential reduction on human health risks as a consequence of the adaptation to the EU legislation on pollutant emissions from the MSWI stack. Analytical and modelled results were obtained. PCDD/F concentrations in environmental media were determined by means of a simple-compartment-multimedia model (air–soil–vegetation model). Predicted and measured PCDD/F concentrations in soils and vegetation were compared, and the effects of MSWI emissions in the environmental media were determined. Human health risks due to PCDD/F emissions from the MSWI were also estimated based on I-TEQ measured and modelled in various environmental media. Cancer risks due to PCDD/F emissions of the plant were 1.07E−07 and 3.08E−09, before and after installation of the clean air system, respectively. On the other hand, cancer risks due to other PCDD/F emission sources in the area were 5.54E−06 and 1.86E−06. Total PCDD/F cancer risks (including those from diet) for the population living in the vicinity of the MSWI were 1.3E−04 and 4.25E−05, respectively (67.6% of reduction). Hazard ratio for total PCDD/F exposure (including diet) decreased during the last 5 years from 1.16 to 0.38. The above data show that other emission sources of PCDD/Fs also have a notable environmental impact on the area under direct influence of the MSWI. [Copyright &y& Elsevier]