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1.
Environ Pollut ; 292(Pt B): 118395, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34687778

RESUMO

In this study, the organ distribution and exposure risk from dietary intake of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were investigated for lotus collected from Ya-er Lake, a lake in Hubei Province, Central China that was historically polluted by the chlor-alkali industry. The highest concentrations of PCDD/Fs were found in the main and fibrous lotus roots, with mean values of 48.9 ± 90.1 pg/g and 94.6 ± 143 pg/g, respectively. In all the investigated samples, Octa-CDD (OCDD) and Octa-CDF (OCDF) were the predominant congeners, at 26% and 17% of Σ17 PCDD/Fs, respectively, followed by 1,2,3,4,6,7,8-HpCDF (9%). The distribution ratios of PCDD/Fs in adjacent lotus organs indicated that PCDD/Fs accumulated easily in edible organs, such as lotus seeds, membrane and leaves. The WHO-TEQ in the edible lotus organs and the probable daily intake (PDI) of lotus products by residents were calculated: the toxic equivalents in the lotus fruit parts reached a mean of 2 pg WHO-TEQ2005/g dw, and the mean weekly intake of lotus products for adolescents living around Ya-er Lake was 2.3 pg WHO-TEQ/kg bw/week. These results suggested that long-term consumption of lotus products from Ya-er Lake presents a health hazard to residents.


Assuntos
Benzofuranos , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Álcalis , China , Dibenzofuranos , Dibenzofuranos Policlorados , Ingestão de Alimentos , Lagos
2.
Environ Pollut ; 292(Pt A): 118265, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601032

RESUMO

Although biomass fuel has always been regarded as a source of sustainable energy, it potentially emits polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study investigated PCDD/F emissions from industrial boilers fired with three types of biomass fuel (i.e., bagasse, coffee residue, and biomass pellets) via stack sampling and laboratory analysis. The measured mass concentrations of PCDD/Fs varied among the boilers from 0.0491 to 12.7 ng Nm-3 (11% O2), with the calculated average international toxic equivalent quantity (I-TEQ) from 0.00195 to 1.71 ng I-TEQ Nm-3 (11% O2). Some of them were beyond the limit value for municipal waste incineration. 2,3,4,7,8-PeCDF could be used as a good indicator of dioxin-induced toxicity of stack flue gases from biomass-fired boilers. The PCDFs/PCDDs ratios were more than 1, likely indicating the formation of dioxins in the boilers favored by de novo synthesis. The emission factor (EF) of total PCDD/Fs averaged 5.35 ng I-TEQ kg-1 air-dry biomass (equivalent to 39.0 ng kg-1 air-dry biomass). Specifically, the mean EF was 6.94 ng I-TEQ kg-1 (52.6 ng kg-1) for biomass-pellet-fired boiler, 11.8 ng I-TEQ kg-1 (74.6 ng kg-1) for coffee-residue -fired boiler, and 0.0277 ng I-TEQ kg-1 (0.489 ng kg-1) for bagasse-fired boilers. The annual PCDD/F emission was estimated to be 208 g I-TEQ in 2020 in China, accounting for approximately 2% of the total national annual emission of PCDD/Fs. The results can be used to develop PCDD/Fs emission inventories and offer valuable insights to authorities regarding utilizing biomass in industry in the future.


Assuntos
Poluentes Atmosféricos , Dibenzodioxinas Policloradas , Poluentes Atmosféricos/análise , Biomassa , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Incineração , Dibenzodioxinas Policloradas/análise
3.
Chemosphere ; 286(Pt 3): 131871, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34426291

RESUMO

Persistent Organic Pollutants (POPs) are a global threat, but impacts of these chemicals upon remote areas such as Antarctica remain unclear. Penguins can be useful species to assess the occurrence of POPs in Antarctic food webs. This work's aim was the evaluation of polychlorodibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in eggs of two penguin species, chinstrap (Pygoscelis antarticus) and gentoo penguins (Pygoscelis papua), breeding in the South Shetland Islands. Results showed a common pattern in POP levels regardless of the species, characterized by a major abundance of PCBs (98 %), followed by PBDEs (1-2%) and PCDD/Fs (<1 %). Concentrations of POPs in chinstrap and gentoo penguin eggs were 482 and 3250 pg/g l.w., respectively. PCBs, PBDEs and PCDD/Fs were found at higher concentrations in chinstrap penguin eggs, being these differences significant for PBDEs. Interspecies differences in POP levels agree well with potential trophic position differences among species due to changes in prey composition and foraging areas. POP profiles were dominated by congeners with a low degree of halogenation. Our results therefore suggest similar sources of POPs in the food webs exploited by both species and in both cases attributable to the long-range transportation rather than to the presence of local sources of POPs. TEQs were found between 1.38 and 7.33 pg/g l.w. and followed the pattern non-ortho dl-PCBs > PCDFs > PCDDs > mono-ortho dl-PCBs. TEQ values were lower than the threshold level for harmful effects in birds of 210 pg/g WHO-TEQ/g l.w.


Assuntos
Bifenilos Policlorados , Dibenzodioxinas Policloradas , Spheniscidae , Animais , Regiões Antárticas , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Furanos , Éteres Difenil Halogenados/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise
4.
J Colloid Interface Sci ; 605: 537-546, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34340038

RESUMO

Herein, a comparative investigation of the Ru-based catalysts with different kinds of supports (TiO2, Al2O3, HZSM-5 SiO2/Al2O3 = 27 and 130, respectively) for catalytic combustion of dichloromethane (DCM) has been performed. The characterization results showed that the C-Cl bond of DCM was cleaved on both the Brønsted and Lewis acid sites of the catalysts. However, the Lewis acid sites were more active than the Brønsted acid sites. The relatively strong Lewis acidity of Ru/TiO2 improved the dissociative adsorption of DCM, accounting for its superior activity. The yield of toxic by-products was strongly associated with the acid types of the catalysts. The Cl species deposited on TiO2 and Al2O3 supports interacted strongly with the Lewis acid sites, thereby promoting the electrophilic chlorination reactions and yielding more polychlorinated by-products, especially highly toxic dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). However, the Cl deposits on Ru/HZSM-5 (SiO2/Al2O3 = 27) with abundant Brønsted acid sites, mainly existed as hydrogen-bonded Cl species, with good mobility and less propensity for chlorinating carbonaceous matter. Moreover, Ru/HZSM-5 (SiO2/Al2O3 = 130) yielded the highest polychlorinated by-products and PCDD/Fs because of its poor redox ability and high surface area. Overall, this study provides valuable insights into the CVOCs catalytic combustion catalysts development.


Assuntos
Dibenzodioxinas Policloradas , Rutênio , Adsorção , Catálise , Dibenzofuranos , Dibenzofuranos Policlorados , Cloreto de Metileno , Dióxido de Silício
5.
Waste Manag Res ; 39(12): 1480-1488, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34766516

RESUMO

Chlorinated contaminants are a cause of significant concern in the development of municipal solid waste (MSW) thermal treatment techniques. This study investigates the efficacy of two calcium (Ca)-based in-furnace additives, calcium oxide (CaO), and calcined dolomite (CD), at reducing the levels of chlorinated contaminants during MSW thermal treatment. The results reveal that Ca-based additives could effectively reduce the chlorine (Cl) content by more than 76.8% and 37.3% in the gas and tar phases, respectively. The total concentration and the international total equivalent (I-TEQ) value of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) were significantly higher under the incineration condition than pyrolysis and gasification conditions. Adding CaO could reduce the total concentration and the I-TEQ value of PCDD/Fs by more than 43.4% and 36.7%, respectively. The reduction effect on PCDD/Fs was more significant in the gaseous phase and the tar phase than the solid phase. CD was more effective than CaO at reducing the chlorinated contaminants, including hydrogen chloride, Cl in the tar phase, and PCDD/Fs. Thus, adding Ca-based sorbents in the furnace during MSW pyrolysis and gasification can effectively reduce PCDD/Fs generation. Based on the experimental results, the mechanism of Ca-based sorbents on the high-temperature homogeneous reaction of PCDD/Fs formation was analysed.


Assuntos
Poluentes Atmosféricos , Benzofuranos , Dibenzodioxinas Policloradas , Poluentes Atmosféricos/análise , Benzofuranos/análise , Cálcio , Dibenzofuranos , Dibenzofuranos Policlorados , Incineração , Resíduos Sólidos
6.
Waste Manag ; 135: 437-447, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34619625

RESUMO

The current derived models for predicting polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) emissions from incineration can only be applied to a specific incinerator due to high deviation or systematic errors. And the models fail to provide quantized guidance for the operation of full-scale municipal solid waste incinerators. To address the problem, explainable Bayesian support vector regression (E-BSVR) has been established to generalized predict and maximumly reduce the PCDD/F emissions. First, forty-two PCDD/F samples were determined from a whole year experiment in a full-scale incinerator. Meanwhile, 1,2,4-trichlorobenzene(1,2,4-TrCBz), carbon monoxide, sulfur dioxide, oxynitride, particulate matter, fluoride, and hydrogen chloride were measured, as input features. Second, after box-cox transformation normalization, and hyperparameters tuning, the R-Squared and root mean square error (RMSE) of the proposed method are 0.983 and 0.044, exhibiting high accuracy. The high accuracy (R-Squared = 0.992) and generalization are also proven on the dataset with high PCDD/F emissions. Then, the performances of BSVR are compared with kernel ridge regression, multiple linear regression, and unary linear regression, indicating afar smaller RMSE of BSVR. Finally, the optimal operating parameters are calculated through local interpretable model-agnostic explanations and the partial dependence plot. Results indicate that reducing the content of organic chlorine in municipal solid waste and inhibiting the deacon reaction are important methods for reducing PCDD/F emissions. The optimal operating parameters for the maximal reduction of PCDD/F emissions are 1,2,4-TrCBz < 0.098 ug/m3, fluoride > 0.452 mg/m3. As a whole, the E-BSVR method can be used as a reliable and accurate approach for the prediction and reduction of PCDD/F emissions.


Assuntos
Poluentes Atmosféricos , Benzofuranos , Dibenzodioxinas Policloradas , Poluentes Atmosféricos/análise , Teorema de Bayes , Benzofuranos/análise , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Fluoretos , Incineração , Dibenzodioxinas Policloradas/análise
7.
J Hazard Mater ; 416: 126216, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492973

RESUMO

Thermal treatment of municipal solid waste incineration fly ash (FA) is an effective method to detoxicate FA and produce secondary material with good utilization properties, but the high temperature induced migration of carbon, chlorine, and catalytic metals from FA to flue gases can result in a considerable reformation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Herein, two typical fly ashes were thermally cotreated with sewage sludge (SS), respectively, and the decomposition and reformation of PCDD/Fs were systematically investigated. Thermal treatment effectively decomposed PCDD/Fs in all samples to a low level well meeting the reutilization criterion of 50 ng WHO-TEQ g-1. Cleavage of the oxygen bridge was identified as the primary decomposition pathway. Compared to mono-treating FA, cotreating FA with SS resulted in a better CaO-Al2O3-SiO2 ternary system for vitrification and effectively suppressed the reformation of PCDD/Fs in off-gases with inhibition efficiencies up to 96%. Based on the variation of chemical speciation of N, P, and S in SS after thermal treatment, SS appeared to be a S-N-containing inhibitor which passivated catalytic metals to suppress PCDD/Fs synthesis. The better suppression on de novo pathway than on chlorophenol-route identified by monitoring PCDD/F-fingerprints evolution further verified the suppression mechanism of passivating catalytic metals.


Assuntos
Benzofuranos , Dibenzodioxinas Policloradas , Cinza de Carvão , Dibenzofuranos , Dibenzofuranos Policlorados , Incineração , Dibenzodioxinas Policloradas/análise , Esgotos , Dióxido de Silício , Resíduos Sólidos/análise
8.
J Environ Manage ; 299: 113584, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488106

RESUMO

A field test was conducted to study the emission and distribution characteristics of dioxins during co-processing of hazardous waste in a multicomponent slurry gasifier (MCSG). The toxicity equivalent concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in all exhaust gas, waste water, and solid waste under both blank condition (i.e., feedstock was normal coal-water slurry) and test condition (i.e., feedstock mixed with hazardous waste and labeling reagents) were analyzed. Results showed that organic matter was fully degraded in the MCSG. The dioxin amount in the black water flash steam increased with the addition of hazardous waste and chlorine in the feedstock, and octachlorodibenzo-p-dioxins (OCDD) with the largest increase is the most easily formed monomer in dioxins. The dioxin amount in all samples was far below the standard limit in China and other countries. This indicates the low environmental risk from dioxins during the co-processing process. The dioxin distribution trend in solid, liquid, and gas phase during co-processing did not change: 86.63%-94.18%, 0.02%-0.13%, and 5.8%-13.23% of PCDDs were distributed in the exhaust gas, waste water, and solid waste, respectively, while 6.10%-22.95%, 0.59%-0.80%, and 76.45%-93.10% of PCDFs were distributed in the exhaust gas, waste water, and solid waste, respectively.


Assuntos
Dioxinas , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Resíduos Perigosos , Incineração , Resíduos Sólidos
9.
Ecotoxicol Environ Saf ; 223: 112541, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352580

RESUMO

Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were investigated in muscle samples from common kestrels (Falco tinnunculus), eagle owls (Bubo bubo), and little owls (Athene noctua) collected in Beijing, China. The concentrations of PCDD/Fs were in the ranges of 22.7-5280, 67.5-1610, and 68.4-3180 pg/g lipid weight (lw), while levels of dioxin-like PCBs ranged from 4.91 to 1560, 8.08-294, and 28.2-3540 ng/g lw, in common kestrel, eagle owl, and little owl, respectively. The main PCDD/Fs congener was 2,3,4,7,8-PeCDF, and CB-153 dominated the seven indicator PCBs. PCB levels have shown a decreasing trend in the last decade for the common kestrel, but not for little owl in Beijing, which exhibited higher levels of pollutants and toxic equivalency (TEQ) values than the other two species. Concentrations of PCDD/Fs, dioxin-like PCBs, and indicator PCBs differed between fledgling and adult raptors for certain species. Raptors in this study generally had a higher TEQ than the no-observed-effect level in the literature, indicating significant exposure risks to PCDD/Fs and dioxin-like PCBs in raptors, especially in adult little owls.


Assuntos
Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Aves Predatórias , Animais , China , Dibenzofuranos , Dibenzofuranos Policlorados , Bifenilos Policlorados/análise
10.
Environ Monit Assess ; 193(9): 605, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34453199

RESUMO

This study determined the indoor air levels of polychlorinated biphenyls (PCBs) in some selected public bars in Southern part of Nigeria. The result obtained was used to carry out health risk assessment of exposure to PCBs in these indoor environment.s. Air samples were obtained from the selected popular bars using polyurethane (PUF) passive samplers. PCB quantification was done using GC-MS operated in selected ionization mode (SIM). Health risk assessment from exposure of these pollutants was determining using toxicity equivalence quotient (TEQ), inhalation risk assessment (IRA), incremental life cancer risk (ILCR), and hazard quotient (HQ). The results showed the average concentration range of 0.15-0.17 µg/m3. The mean TEQ at various locations was 0.00050 ng WHO-TEQ/m3, while the calculated daily inhalation exposure values were 0.0004 ng TEQ kg-1 day-1 for adults and 0.0002 ng TEQ kg-1 day-1 for children. The values of IRA, ILCR for the children, and HQs for both adults and children were higher than the WHO permissible limits. The study revealed that both non-carcinogenic and carcinogenic risks associated with longtime exposure to PCBs in the indoor environment public bars.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Adulto , Criança , Dibenzofuranos Policlorados , Monitoramento Ambiental , Poluentes Ambientais/análise , Humanos , Exposição por Inalação/análise , Bifenilos Policlorados/análise , Medição de Risco
11.
Sci Total Environ ; 798: 149154, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333438

RESUMO

Suppressing the formation of chlorinated aromatics (Cl-aromatics) by chemical inhibitors is an important measure to reduce dioxin emission from the solid waste incineration plants. In this study, we first investigated the reduction effect of a novel inhibitor sodium thiocyanate (NaSCN) on the emission of dioxins in 2 full-scale solid waste incineration systems. Injection of NaSCN solution into the higher temperature flue gas resulted in about 60% reduction in the concentration of total tetra- to octa-chlorinated dibenzo-p-dioxins and dibenzofurans in stack flue gas. The suppression effect was further verified by a laboratory study on the chlorination of naphthalene over model fly ashes with or without NaSCN addition. By characterizing the reaction products between NaSCN and key catalysts Cu and Fe chlorides, two main suppression mechanisms were proposed: (i) reduction of highly active cupric chloride (CuCl2) and ferric chloride (FeCl3) to less active cuprous chloride (CuCl) and ferrous chloride (FeCl2), (ii) sulfidation of Cu chlorides. The laboratory study indicated that the unreacted NaSCN in the combustion flue gas could be mainly decomposed into Na2S, C3N4, Na2S2O3, NaS2, Na2SO4, CO2, SO2, NO2 and COS. These decomposition products are low toxic or can be effectively removed by the air pollution control devices. CAPSULE: NaSCN suppressed the formation of chlorinated aromatics in combustion flue gas mainly through inducing the reduction of highly active Cu (II) and Fe (III) chlorides.


Assuntos
Incineração , Dibenzodioxinas Policloradas , Dibenzofuranos , Dibenzofuranos Policlorados , Dibenzodioxinas Policloradas/análise , Resíduos Sólidos , Tiocianatos
12.
Environ Pollut ; 289: 117798, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34340177

RESUMO

The variation of municipal solid waste (MSW) components and the improvement of incinerators have an obvious effect on dioxin emissions. However, there is a knowledge gap on dioxin distribution characteristics following China's implementation of MSW classification. To reveal the fate of dioxins under ultra-low emission standards in leading cities in China, a systematic investigation was carried out in a typical modern MSW incinerator in Shenzhen, China. The dioxin mass balance was built using improved models, which included expanded samples, e.g., the leachate, the raw gas and raw ash from boiler, and the chemicals and residuals from air pollution control devices (APCDs). The results indicated a positive dioxin balance of 0.88 µg I-TEQ/t MSW according to the conventional method containing fly ash, bottom ash, and stack gas. In the new model revealing dioxin characteristics after APCDs, a higher value of 0.89 µg I-TEQ/t MSW was found due to the leachate, slaked lime, and activated carbon-containing dioxins. The distribution of dioxins in output samples of fly ash, bottom ash, stack gas, and leachate were 149.0 %, 41.8 %, 1.6 %, and 0.6 % of MSW, respectively. For incineration itself, the balance was 0.85 µg I-TEQ/t MSW, which indicated the possible release owing to the "memory effect" for the other two methods. This study provided new insight for the accurate estimation of dioxin emissions and a typical case report of MSW incineration with ultra-low dioxin emissions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Dioxinas , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cinza de Carvão , Dibenzofuranos Policlorados , Dioxinas/análise , Humanos , Incineração , Resíduos Sólidos
13.
Environ Pollut ; 289: 117869, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388555

RESUMO

Mycoremediation of unsterilized PCDD/F-contaminated field soil was successfully demonstrated by solid-state fermentation coupled with Pleurotus pulmonarius utilizing a patented incubation approach. The experiments were carried out in four setups with two as controls. The contaminated soil was homogenously mixed with solid inocula, 1:0.5 dry w/w, resulting in an initial concentration of 4432 ± 623 ng WHO-TEQ kg-1. After a 30-day incubation under controlled conditions, the overall removal (approx. 60%) was non-specific. The removal was attributed to degradation by extracellular ligninolytic enzymes and uptake into the fruiting tissue (~110 ng WHO-TEQ kg-1 of mushroom). Furthermore, less recalcitrant chlorinated metabolites were found, implying ether bond cleavage and dechlorination happened during the mycoremediation. These metabolites resulted from the complex interaction between P. pulmonarius and the indigenous microbes from the unsterilized soil. This study provides a new step toward scaling up this mycoremediation technique to treat unsterilized PCDD/F-contaminated field soil.


Assuntos
Benzofuranos , Dibenzodioxinas Policloradas , Poluentes do Solo , Benzofuranos/análise , Dibenzofuranos Policlorados , Pleurotus , Dibenzodioxinas Policloradas/análise , Solo , Poluentes do Solo/análise
14.
Sci Total Environ ; 801: 149690, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34419913

RESUMO

Updated assessment on transfer of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) from feed to food is essential for understanding human exposure risk. A controlled feeding experiment was conducted for laying hens to reevaluate the transfer characteristics of dioxin-like compounds from feed to egg. Two fortified diets (1.17 and 5.13 pg TEQ g-1 dry weight), made by blending with fly ash, were fed to laying hens for 14 days, followed by 28-days depletion. Levels of ∑TEQPCDD/Fs+DL-PCBs in eggs rapidly increased once exposure started, reaching at 1.98 and 6.86 pg TEQ g-1 lw at the end of exposure for low- and high-exposure groups, respectively, and dropped to under the European legislation (maximum levels: 5.0 pg TEQ g-1 lw) after 28-days depletion. The quantitative depletions showed that the half-lives (T1/2) of ∑TEQPCDD/Fs in eggs were 23 and 14 days for low- and high-exposure groups, respectively. The depletion and accumulation rates of PCDD/Fs were in the range of 0.026-0.151 and 0.005-0.016 day-1, respectively, representing that the T1/2 of PCDD/Fs in eggs ranged from 5 to 27 days. The depletion kinetics of DL-PCBs was not significant in egg. The hens with higher laying rates exhibited shorter T1/2 of PCDD/Fs, implying that increasing laying rate could expedite the depletion of PCDD/Fs in egg. The T1/2 of PCDD/Fs in egg were negatively correlated with the chlorine number, indicating that lower chlorinated congeners tended to be retained in the egg. Transfer rates of PCDD/Fs were in the range of 4-19%, which were lower than the previous results. These results were attributed to short exposure time and low bioavailability of PCDD/Fs in fly ash. Estimations of dietary intake highlighted the dietary risk of PCDD/Fs from feed to egg, which would pose limited adverse effects on human health.


Assuntos
Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Animais , Galinhas , Dibenzofuranos , Dibenzofuranos Policlorados , Dieta , Dioxinas/análise , Ovos/análise , Feminino , Contaminação de Alimentos/análise , Humanos , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise
15.
Mar Pollut Bull ; 172: 112884, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454391

RESUMO

Surface sediments from the Yesilirmak River and the near coastal area in the Black Sea were collected using sediment traps to assess the spatial distributions of persistent organic pollutants and find their potential sources. Analyses were carried out to determine the concentrations of the persistent organic pollutants of seventeen polychlorinated dibenzo-p-dioxins and dibenzofurans, sixteen polycyclic aromatic hydrocarbons, seven polychlorinated biphenyls, and eight organochlorine pesticides using high-resolution gas chromatography-mass spectrometry and gas chromatography-tandem mass spectrometry systems. Analysis showed that the three main components of persistent organic pollutants (polychlorinated dibenzo-p-dioxins and dibenzofurans, polycyclic aromatic hydrocarbons, and organochlorine pesticides) primary sources are industrial activities. In addition, the widespread occurrence of persistent organic pollutants in the watershed surface sediments taken from the Yesilirmak River basin showed that agricultural and urban areas are also diffuse persistent organic pollutants sources.


Assuntos
Bifenilos Policlorados , Poluentes Químicos da Água , Mar Negro , Dibenzofuranos Policlorados , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos , Poluentes Orgânicos Persistentes , Bifenilos Policlorados/análise , Rios , Poluentes Químicos da Água/análise
16.
Sci Total Environ ; 794: 148504, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34198078

RESUMO

Polychlorodibenzo-p-dioxins, polychlorodibenzo-furans (PCDD/Fs) and dioxin-like polychlorobiphenyls (DL-PCBs) enter the food chain from the environment. In this study, we report the 2008-2018 time-trends in the PCDD/F and DL-PCB contamination of milk from buffaloes fed on local forage in rural areas of the Campania region. Validated according to QA/QC criteria, the dataset (N = 808 on a total of 2068 samples, after excluding follow-up results and outliers) was computed on the upper-bound value pg WHO-TEQ2005 g-1fat. We assessed time-trends and assayed baseline contamination levels, which displayed log-normal distribution. A significant decreasing trend (p < 0.01) was observed from 2008 to 2009 and 2010; the P50-P95 range fell from 2.37-8.48 pg WHO-TEQ2005 g-1fat (N = 393) in 2008 to 1.73-4.61 in 2009 (N = 86) and to 0.67-1.46 in 2010 (N = 42). From 2010 to 2018 (N = 329), no significant variation was found among years and the related dataset fitted a log-normal distribution (p < 0.05). Occurrence descriptors indicated that the baseline contamination of dairy products (mean = 0.54; P50-P95 = 0.47-1.24) in the Campania Region was well below the EU regulatory limit in force (5.5 pg WHO-TEQ2005 g-1fat). Given the Tolerable Weekly Intake of 2 pg WHO-TEQ kg-1 body weight (bw) proposed by the EFSA for PCDD/Fs and DL-PCBs, this level of baseline contamination is discussed with regard to the orientation of food safety and food security risk connected with buffalo mozzarella cheese production.


Assuntos
Benzofuranos , Dioxinas , Poluentes Ambientais , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Animais , Benzofuranos/análise , Búfalos , Dibenzofuranos , Dibenzofuranos Policlorados , Dioxinas/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Itália , Leite/química , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise
17.
Waste Manag ; 131: 331-340, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34218066

RESUMO

Several studies have reported the release of halogenated persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) associated with open burning of municipal solid waste. Considering soil as a sink for such organic contaminants, we conducted an in-depth study on the surface soil concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and sixteen USEPA enlisted PAHs collected from thirteen zones of the two major municipal dumpsites, Kodungaiyur dumpsite (KDS) and Perungudi dumpsite (PDS) of Chennai city. Indigenous microbes from dumpsite soil samples were isolated and identified based on 16S rRNA sequencing and phylogenetic analysis. Using indigenous microbes, we have elucidated the bioavailability of the targeted organic pollutants for each site.Range of Σ17PCDD/Fs, Σ25PCBs and ∑16PAHs varied between 3.96-612 pg/g (96.0 pg/g; median), ND-182 ng/g (6.35 ng/g; median) and 0.62-3649 ng/g (64.3 ng/g; median), respectively. All the dumpsite samples showed bioavailability for POPs and PAHs. Toxicity equivalent values (TEQs) associated with dioxin-like PCBs and PCDD/Fs from the zones where dumped municipal solid wastes were collected from electronic-waste/IT-corridor/port areas and toxic PAHs from the zone receiving wastes from the industrial corridor of the city were higher than the soil permissible limit prescribed by the World Health Organization.


Assuntos
Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Hidrocarbonetos Policíclicos Aromáticos , Disponibilidade Biológica , Dibenzofuranos , Dibenzofuranos Policlorados , Furanos , Índia , Filogenia , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , RNA Ribossômico 16S , Solo
18.
Mar Pollut Bull ; 171: 112763, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34332355

RESUMO

This study determines the levels of PCDD/Fs and PCBs in Baltic fish caught in ICES areas 24, 25, and 26, and the related risk for fish consumers in relation to the newly established Tolerable Weekly Intake dose (TWI) (2 pg WHO-TEQ kg --1 body weight). The total PCDD/F/DL-PCBs toxic equivalents in the fish muscle ranged from 0.12 to 10.34 pg WHO-TEQ g - -1 wet weight. Salmon muscles contained the highest average concentration and cod the lowest, below 0.5 pg WHO-TEQ g - -1 wet weight of total TEQ. The average intake of PCDD/F/DL-PCBs (portion of fish 200 g) was 91-2420% of the TWI for children, and 30-799% of the TWI for adults. It appears that despite the decreased levels of PCDD/F and PCBs in Baltic fish, in relation to the newly established TWI dose, this decrease is not enough to make the Baltic fish safe for frequent consumers.


Assuntos
Benzofuranos , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Adulto , Animais , Benzofuranos/análise , Criança , Dibenzofuranos , Dibenzofuranos Policlorados , Dioxinas/análise , Contaminação de Alimentos/análise , Humanos , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise
19.
J Hazard Mater ; 420: 126658, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329087

RESUMO

Microplastic (MP) pellets were sampled from six sandy beaches around Taiwan in order to investigate the concentrations and compositions of POPs, including: PCDD/Fs, PBDD/Fs, PBDEs, PCBs, PBBs, and their congeners. The concentrations of PCDD/Fs on the surface (Cs) of MP pellets from the six sampling sites were from 1.9 to 14.6 pg∙g-1, while the overall concentrations within MPs (Ct) were from 95.0 to 1110.6 pg∙g-1. As PCDD/Fs were adsorbed into the inner part of MPs, a ratio of the total concentrations to surficial concentration of MPs (Ct/Cs) was as high as 355.2 times. The Ct/Cs of other POPs were also significant, such as PBDEs being found up to 8068 times, which could be attributed to artificial addition during manufacturing processes as flame-retardant substances. Primary compositions of PCDD/Fs, PBDD/Fs, and PBDEs on the MPs in our POP congener analysis were all found containing species with higher number of chlorine or bromine, which were adsorbed on the MP surface more easily due to their relative higher KOW.


Assuntos
Bifenilos Policlorados , Dibenzodioxinas Policloradas , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Microplásticos , Poluentes Orgânicos Persistentes , Plásticos , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise
20.
Chemosphere ; 285: 131392, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34242988

RESUMO

A field experiment was conducted in a modern municipal solid waste (MSW) incineration power plant to explore the feasibility of using chemical agglomeration agent anionic polyacrylamide (PAM) to reduce the atmospheric emission of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Spraying PAM solution into the cooling tower caused an obvious decrease in the volume fraction of ultrafine and fine particles with diameter of 0.3-30 µm in BF fly ash, and a significant reduction in dust content in stack gas. The increased agglomeration of particles promoted the removal of particle-phase PCDD/Fs by BF, and thus resulted in a lower atmospheric emission of PCDD/Fs. The calculated removal efficiency of PCDD/Fs by BF was almost positively proportional to the concentration of PAM solution, while inversely proportional to the average content of dusk in stack gas. Compared with the control treatment, the spraying of 0.1 g/L PAM solution enhanced the removal efficiency of total tetra-to octa-CDD/Fs (∑PCDD/Fs) from 93.8% to 97.8% by BF, and resulted in a decrease of 47.0% in the concentration of international toxicity equivalent (I-TEQ) in stack gas. During the experiment of 2 d, the spraying of PAM solution did not induce a significant change in the differential pressure of BF, and did not essentially affect the partitioning behaviors of PCDD/F homologues between flue gas and BF fly ash. In view of technical safety and low cost, PAM application is recommended for reducing the atmospheric emission of PCDD/Fs from MSW incineration system.


Assuntos
Poluentes Atmosféricos , Benzofuranos , Dioxinas , Dibenzodioxinas Policloradas , Resinas Acrílicas , Poluentes Atmosféricos/análise , Benzofuranos/análise , Cinza de Carvão , Dibenzofuranos , Dibenzofuranos Policlorados , Dioxinas/análise , Incineração , Dibenzodioxinas Policloradas/análise , Resíduos Sólidos
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