Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.869
Filtrar
1.
Sci Total Environ ; 740: 140136, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927574

RESUMO

Children are exposed to many potentially toxic compounds in their daily lives and are vulnerable to the harmful effects. To date, very few non-invasive methods are available to quantify children's exposure to environmental chemicals. Due to their ease of implementation, silicone wristbands have emerged as passive samplers to study personal environmental exposures and have the potential to greatly increase our knowledge of chemical exposures in vulnerable population groups. Nevertheless, there is a limited number of studies monitoring children's exposures via silicone wristbands. In this study, we implemented this sampling technique in ongoing research activities in Montevideo, Uruguay which aim to monitor chemical exposures in a cohort of elementary school children. The silicone wristbands were worn by 24 children for 7 days; they were quantitatively analyzed using gas chromatography with tandem mass spectrometry for 45 chemical pollutants, including polychlorinated biphenyls (PCBs), pesticides, polybrominated diphenyl ethers (PBDEs), organophosphorus flame retardants (OPFRs), and novel halogenated flame-retardant chemicals (NHFRs). All classes of chemicals, except NHFRs, were identified in the passive samplers. The average number of analytes detected in each wristband was 13 ±3. OPFRs were consistently the most abundant class of analytes detected. Median concentrations of ΣOPFRs, ΣPBDEs, ΣPCBs, and dichlorodiphenyltrichloroethane (DDT) and its metabolites (dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) were 1020, 3.00, 0.52 and 3.79 ng/g wristband, respectively. Two major findings result from this research; differences in trends of two OPFRs (TCPP and TDCPP) are observed between studies in Uruguay and the United States, and the detection of DDT, a chemical banned in several countries, suggests that children's exposure profiles in these settings may differ from other parts of the world. This was the first study to examine children's exposome in South America using silicone wristbands and clearly points to a need for further studies.


Assuntos
Poluentes Ambientais , Retardadores de Chama/análise , Praguicidas , Criança , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Organofosfatos , Silicones , América do Sul , Uruguai
2.
J Environ Sci (China) ; 97: 180-185, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933733

RESUMO

Novel brominated flame retardants (NBFRs) were investigated in Arctic air and soil samples collected from Ny-Ålesund and London Island, Svalbard, during Chinese scientific research expeditions to the Arctic during 2014-2015. The concentrations of Σ9NBFRs in the Arctic air and soil were 4.9-8.7 pg/m3 (average 6.8 pg/m3) and 101-201 pg/g dw (average 150 pg/g dw), respectively. The atmospheric concentration of hexabromobenzene (HBB) was significantly correlated with that of pentabromotoluene (PBT) and pentabromobenzene (PBBz), suggesting similar source and environmental fate in the Arctic air. No significant spatial difference was observed among the different sampling sites, both for air and soil samples, indicating that the effects of the scientific research stations on the occurrence of NBFRs in the Arctic were minor. The fugacities from soil to air of pentabromoethylbenzene (PBEB), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE), and decabromodiphenylethane 1,2-bis (pentabromophenyl) ethane (DBDPE) were lower than the equilibrium value, indicating a nonequilibrium state of these compounds between air and soil, the dominant impact of deposition and the net transport from air to soil. The correlation analysis between the measured and predicted soil-atmosphere coefficients based on the absorption model showed that the impact of the soil organic matter on the distribution of NBFRs in the Arctic region was minor. To the best of our knowledge, this work is one of the limited reports on atmospheric NBFRs in the Arctic and the first study to investigate the occurrence and fate of NBFRs in the Arctic soil.


Assuntos
Retardadores de Chama/análise , Regiões Árticas , Atmosfera , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Ilhas , Londres , Solo , Svalbard
3.
Chemosphere ; 254: 126766, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957264

RESUMO

Co-pyrolysis of brominated flame retardants (BFRs) with polymeric materials prevails in scenarios pertinent to thermal recycling of bromine-laden objects; most notably the non-metallic fraction in e-waste. Hydro-dehalogenation of aromatic compounds in a hydrogen-donating medium constitutes a key step in refining pyrolysis oil of BFRs. Chemical reactions underpinning this process are poorly understood. Herein, we utilize accurate density functional theory (DFT) calculations to report thermo-kinetic parameters for the reaction of solid polyethylene, PE, (as a surrogate model for aliphatic polymers) with prime products sourced from thermal decomposition of BFRs, namely, HBr, bromophenols; benzene, and phenyl radical. Facile abstraction of an ethylenic H by Br atoms is expected to contribute to the formation of abundant HBr concentrations in practical systems. Likewise, a relatively low energy barrier for aromatic Br atom abstraction from a 2-bromophenol molecule by an alkyl radical site, concurs with the reported noticeable hydro-debromination capacity of PE. Pathways entailing a PE-induced bromination of a phenoxy radical should be hindered in view of high energy barrier for a Br transfer into the para position of the phenoxy radical. Adsorption of a phenoxy radical onto a Cu(Br) site substituted at the PE chain affords the commonly discussed PBDD/Fs precursor of a surface-bounded bromophenolate adduct. Such scenario arises due to the heterogeneous integration of metals into the bromine-rich carbon matrix in primitive recycling of e-waste and their open burning.


Assuntos
Retardadores de Chama/análise , Polietileno/química , Bromo , Halogenação , Hidrocarbonetos Bromados/análise , Cinética , Fenóis , Pirólise , Reciclagem
4.
Environ Pollut ; 265(Pt B): 114970, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32806447

RESUMO

A better understanding of the sources of organophosphate esters (OPEs) is a prerequisite for OPE control and the establishment of related environmental policies. Sources of OPEs in 35 major inflow rivers to the Bohai Sea of China were quantitatively analyzed using three effective receptor models (principal component analysis-multiple linear regression (PCA-MLR), positive matrix factorization (PMF), and Unmix) in this paper. The similarities and differences in results from PCA-MLR, PMF, and Unmix were discussed in depth. All three models well predicted the spatial variability of the total concentrations of nine OPEs (triethyl phosphate, tri-n-butyl phosphate, triisobutyl phosphate, tri (2-ethylhexyl) phosphate, tri (2-chloroethyl) phosphate, tris(1-chloro-2-propyl) phosphate, tris(1,3-dichloro-2-propyl) phosphate, triphenyl phosphate, and triphenylphosphine oxide) (∑9OPEs) (r2 = 0.90-0.96, p = 0.000) and explained 98.4%-101.2% of the observed ∑9OPEs. The predicted ∑9OPEs values from each pairwise model were significantly correlated (r2 = 0.88-0.91, p = 0.000). Three OPE sources were extracted by all three models: rigid and flexible polyurethane foam/coating, cellulosic/acrylic/vinyl polymer/unsaturated polyester, and polyvinyl chloride, contributing 49.9%, 29.7%, and 20.5% by PCA-MLR, 57.9%, 28.6%, and 13.5% by PMF, and 47.9%, 30.8%, and 22.4% by Unmix to the ∑9OPEs, respectively. PMF was recommended as the preferred receptor model for analyzing OPE sources in water during the monitoring period because of its optimal performance.


Assuntos
Retardadores de Chama/análise , Rios , China , Monitoramento Ambiental , Ésteres , Organofosfatos
5.
Sci Total Environ ; 737: 140222, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783844

RESUMO

In the present study we examined spatial and seasonal trends in the levels of a wide suite of semi-volatile organic compounds (SVOCs) in brown trout (Salmo trutta) and mottled sculpin (Cottus bairdii) in East Canyon Creek, Utah, USA, an effluent-dominated stream during summer months. Fish samples were collected from four sampling sites, including one reference site upstream, and three sites at incremental distances downstream of the effluent discharge over multiple seasons. The samples were analyzed for 218 lipophilic contaminants, including pesticides and their metabolites, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and polybrominated diphenyl ethers (PBDEs) and other flame retardants. Some PAHs, pesticides and their metabolites, PCBs, PBDEs and other flame retardants were measured in mottled sculpin (11 analytes) and brown trout (17 analytes). Hexachlorobenzene (HCB), p,p'-DDE, BDE-47 and triphenyl phosphate (TPHP) were the most frequently detected contaminants in mottled sculpin and brown trout, while BDE-47 and p,p'-DDE were measured at the highest concentrations, reaching up to 73 and 19 ng/g wet weight, respectively. Our results indicated that snowmelt did not alter accumulation of the examined lipophilic contaminants, and no consistent seasonal differences were observed in their accumulation. A spatial pattern was observed for PBDE congeners, where lowest levels were measured in fish tissues from a reference site, and highest concentrations were measured in fish collected downstream of the effluent discharge, indicating that municipal effluent discharge contributes to the elevated PBDE levels in fish residing in this effluent-dominated stream. We further calculated screening level consumption risks following United States Environmental Protection Agency (EPA) methods, and identified the importance of considering discharge gradients in effluent-dominated systems during bioaccumulation assessments.


Assuntos
Retardadores de Chama/análise , Bifenilos Policlorados/análise , Compostos Orgânicos Voláteis , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Estações do Ano , Utah
6.
Sci Total Environ ; 739: 140049, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758951

RESUMO

The present study determined contamination levels of POPs, such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs), in oysters (Saccostrea mordax) collected throughout the seacoast of Okinawa, Japan and their geographic distribution. PCBs, DDTs, CHLs, PBDEs and HBCDs were detected in almost all the oyster samples analyzed and higher concentrations of PCBs, DDTs and CHLs were found in oysters from southwestern populated areas. On the other hand, HBCDs in oysters showed similar levels throughout Okinawa and the highest concentration in a northern rural site with less human and industrial activities, although oyster concentrations of PBDEs were relatively lower. When POPs in expanded polystyrene (EPS) buoys and polystyrene foam debris floated and drifted on coastal seawater were analyzed, extremely high concentrations of HBCDs were detected in some of these EPS buoys and polystyrene foam debris but other POPs were below the limit of detection in all the samples. To evaluate the specific exposure route of HBCDs for oysters, we further analyzed HBCD diastereomers, and PCB congeners by way of comparison, in seawater and sediment samples collected at an urban site and a rural site and estimated their biota (oyster)-sediment accumulation factors (BSAF) and bioaccumulation factors (BAF). Interestingly, the highest log BAF values were found for α-HBCD despite its lower log Kow than those of γ-HBCD and PCB congeners, although log BSAF values for HBCDs were lower than those for PCBs. Considering that α-HBCD was detected in a few polystyrene foam samples as the predominant diastereomer, oysters inhabiting the coastal region of Okinawa might be frequently exposed to micronized polystyrene foam particles containing HBCDs.


Assuntos
Poluentes Ambientais , Retardadores de Chama/análise , Hidrocarbonetos Bromados/análise , Ostreidae , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Biológico , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Japão , Poliestirenos , Inquéritos e Questionários
7.
J Chromatogr A ; 1626: 461349, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797829

RESUMO

In the present work, a very sensitive and fully automated direct immersion PAL SPME Arrow procedure, coupled with GC-MS, has been developed and validated for determination of nine phosphorus flame retardants in different types of water samples (river, drinking and rainwater). PDMS/DVB was selected among three commercially available SPME Arrows (PDMS/DVB, DVB/PDMS/CWR and PDMS/CWR), since it resulted in the best sensitivity. The important experimental parameters were optimized via a central composite design response surface methodology and as result, extraction time of 65 min, extraction temperature of 80 °C and added salt concentration of 19% (w/v), were selected as the optimum values. The optimized method showed linear response over the calibration range (2 - 500 ng L-1), with R2-values higher than 0.9937. The precision (RSD%) measured by replicate analyses (n = 7) was estimated at 2 and 100 ng L-1 and was less than 29% and 21%, respectively. The LOQ of PAL SPME Arrow, calculated as S/N = 10, was between 0.2 and 1.2 ng L-1 (for triphenyl phosphate and tris-(1­chloro­2-propyl) phosphate, respectively) with extraction efficiencies between 5.9 and 31% (for tris-(1,3-dichloro-2-propyl) phosphate and tri-n­butyl phosphate, respectively). To assess the performance of the developed technique for real samples, two river water samples, tap water from two regions and a rainwater sample were analyzed. Most of the target analytes were observed in the river samples with concentrations of 1.0 - 250 ng L-1 and the obtained recoveries at 50 ng L-1 ranged between 60 and 107%. Considering the figures of merit of the optimized method, PAL SPME Arrow-GC-MS showed to be the most sensitive analytical approach for determination of phosphorus flame retardants in water, with satisfying precision and accuracy, compared with conventional SPME-NPD, LLE-GC-MS and SPE-LC-MS/MS.


Assuntos
Retardadores de Chama/análise , Fósforo/análise , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Automação , Dimetilpolisiloxanos/química , Cromatografia Gasosa-Espectrometria de Massas , Polivinil/química , Soluções
8.
J Chromatogr A ; 1626: 461356, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797836

RESUMO

The presence of organophosphate esters (OPEs) in everyday commodities such as furniture, household appliances and baby toys have rendered these contaminants ubiquitous in environmental fates such as air, water, soils and biota. Their presence in food-related species suggests that an additional route of exposure to these esters for the general population is fish intake through diet. Their incipient toxicity and carcinogenetic behaviour make it essential to develop methods for determining OPEs in fish samples. In this paper we have developed a new method for determining 9 OPEs based on the QuEChERS extraction method followed by a simple clean-up using a novel device for selective lipid removal (LipiFiltr) and GC-MS/MS to extract these compounds from fish samples regardless of lipid content. QuEChERS salt packet optimisation and clean-up strategies such as liquid-liquid extraction, dispersive-solid phase extraction and LipiFiltr were tested. Our results showed that EN 15662 method salts and Lipifiltr were the best combination to produce efficient analyte apparent recovery (67-116%) and negligible matrix effects (<10%). Limits of detection ranged from 0.05 ng g-1 (dry weight) for TiBP and TBP to 2.00 ng g-1 (dry weight) for TCEP. Fish samples from four fish species were determined with a median concentration of ΣOPEs 5.31 ng g-1 on a wet weight basis, with TBP, TiBP and TCPP as the main contenders. Estimates of exposure and risk associated with consuming these compounds via dietary intake showed low levels of concern for the population of Tarragona.


Assuntos
Ésteres/análise , Peixes/metabolismo , Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Organofosfatos/análise , Plastificantes/análise , Medição de Risco , Espectrometria de Massas em Tandem , Adolescente , Adulto , Idoso , Animais , Criança , Dieta , Monitoramento Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem/métodos , Adulto Jovem
9.
Sci Total Environ ; 743: 140874, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758856

RESUMO

Atmospheric concentration of legacy (LFRs) and emerging flame retardants (EFRs) including 8 polybrominated diphenyl ethers (PBDEs), 6 novel brominated flame retardants (NBFRs), 2 dechlorane plus isomers (DP), and 8 chlorinated organophosphate flame retardants (OPFRs) were consecutively measured in eight major cities across Pakistan. A total of 96 samples (48 PM2.5 & 48 PUFs) were analyzed and the concentrations of ∑8PBDEs (gaseous+particulate) ranged between 40.8 and 288 pg/m3 with an average value of 172 pg/m3. ∑6NBFRs ranged between 12.0 and 35.0 pg/m3 with an average value of 22.5 pg/m3 while ∑8OPFRs ranged between 12,900-40,800 pg/m3 with an average of 24,700 pg/m3. Among the studied sites, Faisalabad city exhibited the higher concentrations of FRs among all cities which might be a consequence of textile mills and garment manufacturing industries. While analyzing the diurnal patterns, OPFRs depicted higher concentrations during night-time. The estimated risks of all groups of FRs from inhalation of ambient air were negligible for all the cities, according to USEPA guidelines. Nonetheless, our study is the first to report gaseous and particulate concentrations of FRs in air on a diurnal basis across major cities in Pakistan, offering insights into the atmospheric fate of these substances in urban areas in a sub-tropical region.


Assuntos
Retardadores de Chama/análise , Atmosfera , Cidades , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Paquistão
10.
Environ Pollut ; 266(Pt 1): 115372, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32814266

RESUMO

Global concern exists regarding human exposure to organic pollutants derived from public open spaces and indoor dust. This study has evaluated the occurrence of 18 polycyclic aromatic hydrocarbons (PAHs), 11 organophosphorus flame retardants (OPFRs) and bisphenol A (BPA). To achieve this, a new simple, efficient and fast multi-residue analytical method based on a fully automated pressurised liquid extraction (PLE) and subsequent quantification by gas chromatography coupled to electron ionization-mass spectrometry (GC-EI-MS) in selected ion monitoring (SIM) mode was developed. The developed method was applied to indoor dust (12 sampling households) and soil derived from two public open spaces (POSs). Among all compounds studied, PAHs were the most ubiquitous contaminants detected in POS soils and indoor dust although some OPFRs and BPA were detected in lower concentrations. An assessment of the incremental lifetime cancer risk (ILCR) was done and indicated a high potential cancer risk from the POS sites and some of the indoor dust sampled sites. However, key variables, such as the actual exposure duration, frequency of contact and indoor cleaning protocols will significantly reduce the potential risk. Finally, the ingestion of soils and indoor dust contaminated with OPFRs and BPA was investigated and noted in almost all cases to be below the USEPA reference doses.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Retardadores de Chama/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Compostos Benzidrílicos , Poeira/análise , Exposição Ambiental/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Organofosfatos/análise , Fenóis , Solo
11.
Environ Pollut ; 266(Pt 2): 115336, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32836048

RESUMO

Black-spotted frogs and bullfrogs from an e-waste polluted area were collected and examined for legacy and emerging organophosphorus flame retardants (PFRs) and plasticizers. Total concentrations of PFRs and plasticizers were 0.62-15 ng/g wet weight (ww) and 316-4904 ng/g ww in muscles, 2.2-59 ng/g ww and 127-5757 ng/g ww in eggs and gonads, and 1.2-15 ng/g ww and 51-1510 ng/g ww in oviducts, respectively. For muscle tissues, concentrations of ∑PFRs, triethyl phosphate, tris-(2-chloroethyl) phosphate, and tris-(chloro-2-propyl) phosphate were significantly higher in the males than females (p < 0.05). However, for reproductive tissues, eggs exhibited higher levels of those contaminants than gonads (p < 0.05). No significant sex difference in levels of plasticizers was observed in muscles. In contrast, levels for (2-ethylhexyl) phthalate, di-n-butyl phthalate, and di-iso-butyl phthalate in gonads were significantly higher than those in eggs (p < 0.05). Significantly negative linear correlations between maternal transfer ratios and log KOW were found in female frogs. Paternal transfer potentials were first significantly and positively correlated to log KOW (<6) and then decreased afterward in the males. These results indicated that parental transfer was answer for the sex-specific accumulation of PFRs and plasticizers in frogs.


Assuntos
Retardadores de Chama/análise , Animais , Ovos/análise , Monitoramento Ambiental , Feminino , Masculino , Organofosfatos , Compostos Organofosforados , Plastificantes/análise , Caracteres Sexuais
12.
Environ Sci Pollut Res Int ; 27(28): 35782-35791, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32601871

RESUMO

In this study, hexabromocyclododecane (HBCD) in riverine and estuarine sediments was investigated in Osaka, Japan. The mean total HBCD concentration detected in sediments ranged from < 0.50 to 130 ng g-1 dry weight. This exceeded the ubiquitous HBCD contamination level found globally but was lower than that in areas affected by point sources, such as textile industries and expanded polystyrene plants. Sewage effluent was one of the suspected point sources of HBCD in the study area. The HBCD concentrations in sediments were highly dependent on certain factors, such as the location of the sampling site (proximity to possible emission sources), sediment properties (silt or sand), and organic substance content. The range of the diastereomer composition of α- and γ-HBCD was wider than that in other studies. Repeatability tests (n = 3) were conducted for all samples to assess the variability in the HBCD concentrations within identical sediment samples. Some variations were observed in the HBCD concentrations and diastereomer compositions within the repeatability test results at some sampling sites; nevertheless, the same samples were extracted and analyzed in triplicate. The bromine contents of the extracts of these samples were analyzed by X-ray fluorescence, and the results agreed well with those estimated from the LC-MS/MS results. From these results, it was confirmed that several sediment samples contained heterogeneously distributed HBCD. The risk characterization ratios (predicted environmental concentration/predicted no-effect concentration) of sites with high HBCD concentrations ranged from 0.1 to 1; thus, further information is required, and the sediment HBCD levels in this region should be continuously studied.


Assuntos
Retardadores de Chama/análise , Hidrocarbonetos Bromados/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida , Monitoramento Ambiental , Sedimentos Geológicos , Japão , Rios , Espectrometria de Massas em Tandem
13.
Environ Sci Pollut Res Int ; 27(31): 39041-39053, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32642893

RESUMO

The presence of polybrominated diphenyl ethers (PBDEs) in the car is due to their use as a flame retardant additive in various car components such as dashboard, plastic parts, seat and headliner cushion foams, insulated cables, and electronic circuits. Ingestion of dust inadvertently or dermal contact to dust are significant pathways of human exposure to pollutants including PBDEs. There are no studies documenting presence of car dust associated flame retardants in Turkey. In the current study, a total of 13 PBDEs congeners were investigated in 62 car dust samples collected from Bursa province of Turkey using glass-fiber filters and a vacuum cleaner. Results of the study showed that congener concentrations were within the range of

Assuntos
Poluição do Ar em Ambientes Fechados/análise , Retardadores de Chama/análise , Adulto , Automóveis , Pré-Escolar , Poeira/análise , Exposição Ambiental/análise , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Turquia
14.
Environ Pollut ; 266(Pt 1): 115240, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32698055

RESUMO

Polybrominated diphenyl ethers (PBDEs) serve as flame retardants in many household materials such as electrical and electronic devices, furniture, textiles, plastics, and baby products. Though the use of PBDEs like penta-, octa- and deca-BDE greatly reduces the fire damage, indoor pollution by these toxic emissions is ever-growing. In fact, a boom in the global market projections of PBDEs threatens human health security. Therefore, efforts are made to minimize PBDEs pollution in USA and Europe by encouraging voluntary phasing out of the production or imposing compelled regulations through Stockholm Convention, but >500 kilotons of PBDEs still exist globally. Both 'environmental persistence' and 'bioaccumulation tendencies' are the hallmarks of PBDE toxicities; however, both these issues concerning household emissions of PBDEs have been least addressed theoretically or practically. Critical physiological functions, lipophilicity and toxicity, trophic transfer and tissue specificities are of utmost importance in the benefit/risk assessments of PBDEs. Since indoor debromination of deca-BDE often yields many products, a better understanding on their sorption propensity, environmental fate and human toxicities is critical in taking rigorous measures on the ever-growing global deca-BDE market. The data available in the literature on human toxicities of PBDEs have been validated following meta-analysis. In this direction, the intent of the present review was to provide a critical evaluation of the key aspects like compositional patterns/isomer ratios of PBDEs implicated in bioaccumulation, indoor PBDE emissions versus human exposure, secured technologies to deal with the toxic emissions, and human toxicity of PBDEs in relation to the number of bromine atoms. Finally, an emphasis has been made on the knowledge gaps and future research directions related to endurable flame retardants which could fit well into the benefit/risk strategy.


Assuntos
Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Monitoramento Ambiental , Poluição Ambiental , Europa (Continente) , Humanos , Plásticos
15.
Chemosphere ; 260: 127461, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32673865

RESUMO

Tris (1-chloro-2-propyl) phosphate (TCPP) is a chlorinated organic phosphate used in various applications as a flame retardant and plasticizer. TCPP is a known suspected carcinogen and is not effectively removed by traditional water treatments such as biological, chlorination, and UV irradiation. In this study, the UV/H2O2 reaction was employed to degrade TCPP in water. TCPP was effectively degraded in the UV/H2O2 reaction by pseudofirst-order kinetics. The second-order rate constant of the reaction between the TCPP and OH radical was determined to be 4.35 (±0.13) × 108 M-1 s-1 using the competition kinetics with nitrobenzene as a reference compound. The degradation of TCPP was affected by the amount of H2O2, pH, and coexisting water components such as HCO3-, NO3-, and humic acid. Approximately 64.2% of total organic carbon (TOC) in TCPP was mineralized in 12 h during the UV/H2O2 reaction, whereas chloride (Cl-) and phosphate (PO43-) ions were identified as ionic byproducts with the recoveries of 96% chlorine (Cl) and 50% phosphorus (P). Five organic transformation products (TPs) of TCPP were also identified using LC-qTOF/MS. Considering the identified TPs, the main degradation pathway of TCPP during the UV/H2O2 reaction was found to be OH-radical-induced hydroxylation. Finally, a 70% decrease in bioluminescence inhibition in Vibrio fischeri was observed during the UV/H2O2 reaction, and the time-toxicity profile was similar to the time-peak area profile of TPs. The result of this study implies that TCPP can be efficiently removed with significant mineralization and toxicity reduction by the UV/H2O2 process.


Assuntos
Compostos Organofosforados/química , Cloretos , Cloro , Retardadores de Chama/análise , Substâncias Húmicas , Peróxido de Hidrogênio/química , Cinética , Organofosfatos/química , Oxirredução , Fosfatos/química , Plastificantes/química , Raios Ultravioleta , Água , Poluentes Químicos da Água/análise , Purificação da Água
16.
Chemosphere ; 260: 127401, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32682128

RESUMO

Fecal matter is a useful noninvasive/nondestructive media for evaluating contaminants in wildlife, as residues therein have been observed to correlate with body burdens. Conservation detection dog-handler teams can be used to optimize the acquisition of fecal samples. To build on previous work, sentinel-species' (i.e. mink (Mustela vison) and otter (Lontra canadensis)) fecal matter was opportunistically located by a detection dog team along the tri-river system of Missoula, Montana, USA. Sediments were also collected. Samples were used to develop an analytical method from fecal matter to determine habitat exposure to the brominated flame-retardants (BFRs): polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), 2-ethylhexyl 2, 3, 4, 5-tetrabromobenzoate (EH-TBB), di (2-ethylhexyl)-2, 3, 4, 5-tetrabromophthalate (BEH-TEBP) and decabromodiphenyl ethane (DBDPE). Sediments contained PBDEs (BDE-99 and BDE-209) and EH-TBB at detection rates of 67%, 33% and 67%, respectively. BDE-99, -209 and EH-TBB were also detected in mink and otter feces, at rates of 81%, 25% and 81%, respectively; plus BEH-TEBP at 13%. BFR levels correlated positively with human population density except along the lower Bitterroot River, where BDE-209 sediment and feces levels exceeded other sites by several orders of magnitude. Fecal matter body burden estimates indicated marginal PBDE exposure. However, exposure to their replacements, EH-TBB and BEH-TEBP, were at levels that may adversely affect healthy Mustelidae populations. Proof-of-concept was achieved; validation results were within established standards for the development of analytical methods. The established application of conservation dog-handler teams to facilitate the collection of fecal matter for BFR analysis represents a valuable, but currently underutilized environmental monitoring tool.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Éteres Difenil Halogenados/análise , Animais , Cães , Retardadores de Chama/análise , Halogenação , Humanos , Hidrocarbonetos Bromados , Montana , Rios
17.
Chemosphere ; 260: 127633, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32683015

RESUMO

To investigate the status of organophosphate flame retardants (OPFRs) in indoor dust in China, published scientific studies were systematically collected and analyzed. The analysis revealed large variations among microenvironments, including offices (median: 14.59 µg/g) and e-waste workshops (median: 13.36 µg/g), with high levels of OPFRs contamination. Chlorinated organophosphate ester flame retardants (Cl-OPFRs) were the dominant OPFRs (52-75%) in most indoor dust samples; however, in e-waste workshops, aryl- and alkyl-OPFRs were the most abundant. As an alternative flame retardant to polybrominated diphenyl ethers (PBDEs), OPFRs concentrations have increased in recent years in indoor environments in China. Urban sources are of greatest concern: Shanghai (mean: 13.54 µg/g), Guangzhou (mean: 10.76 µg/g), and Beijing (mean: 9.37 µg/g) have high ΣOPFRs contamination levels in indoor dust. Compared to other countries, the OPFRs concentrations in indoor dust in all studied microenvironments from China (median: 8.81 µg/g) were low. The estimated daily intakes of ΣOPFRs by dust ingestion for adults and children were 2.12 and 11.06 ng/kg/body weight/day (average), respectively. Human exposure to OPFRs through the accidental intake of indoor dust does not pose a direct health risk to the Chinese population. However, indoor dust ingestion is an important route for human exposure to OPFRs.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Retardadores de Chama/análise , Organofosfatos/análise , Adulto , Poluição do Ar em Ambientes Fechados/análise , Pequim , Peso Corporal , Criança , Pré-Escolar , China , Contaminação de Medicamentos , Poeira/análise , Ingestão de Alimentos , Exposição Ambiental/análise , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Halogenação , Humanos
18.
Chemosphere ; 260: 127601, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32688318

RESUMO

This study evaluates the prevalence of eight priority polybrominated diphenyl ethers (PBDEs; -28, -47, -99, -100, -153, -154, -183 and -209) and six novel brominated flame retardants (NBFRs; pentabromotoluene (PBT), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenyl ethane (DBDPE)) in biosolids samples from 15 wastewater treatment plants (WWTPs) in Western Australia. Analytes were extracted using selective pressurized liquid extraction (S-PLE) and quantified by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) operated in electron impact (EI) ionization mode. ∑8PBDE levels in biosolids ranged from 11 to 18,000 µg/kg dw with a median concentration of 1800 µg/kg dw. BDE-209 was the most prevalent congener constituting a median of 98% of ∑8PBDE concentrations in samples with BDE-99, -47 and -100 each typically contributing less than 3% to total levels. NBFRs were detected in 71% of samples with ∑6NBFR levels ranging between ND-1100 µg/kg dw (median; 600 µg/kg dw). Levels of DBDPE greatly exceeded those of all other NBFRs, while the next most prevalent compounds were EH-TBB and HBB. Australia produced approximately 327,000 dry tonnes of biosolids in 2017, of which approximately 75% was beneficially utilized on farmland as a fertilizer. Based on these results, an estimated 440 kg of BDE-209 and 150 kg of DBDPE are applied to agricultural land via biosolids applications annually in Australia. This study provides the first account of NBFR concentrations in Australian biosolids.


Assuntos
Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Eliminação de Resíduos Líquidos , Agricultura , Austrália , Biossólidos , Bromobenzenos , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados/análise , Halogenação , Espectrometria de Massas em Tandem , Águas Residuárias/análise , Austrália Ocidental
19.
Environ Pollut ; 265(Pt B): 114924, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32516681

RESUMO

Novel brominated flame retardants (NBFRs) are now ubiquitous in the environment with the extensive production and application. In the present study, pentabromotoluene (PBT), hexabromobenzene (HBB) and decabromodiphenyl ethane (DBDPE) were spiked into the sediments where mudsnails (Bellamya aeruginosa) were cultivated. In the 35-day enrichment process, the highest concentration of the three NBFRs measured in mudsnail is 2.0 mg/kg, 22 mg/kg and 5.2 mg/kg dry weight (dw), respectively. The average enrichment of NBFRs in viscera was about 3 times of pleopod with the same mass. Meanwhile, the parent mudsnails can transfer NBFRs to their offspring. The removal half-life of the three NBFRs was in the range of 2.6 and 5.7 days according to the first-order kinetic equation. Several degradation products of the NBFRs were detected in mudsnail samples, which were exposed to single substance. 2,4,6-tribromotoluene was identified as degradation product of PBT; 1,2,4,5-tetrabromobenzene and 1,2,4-tribromobenzene were identified as debromination products of HBB. Possible degradation pathways were further proposed. Additionally, mudsnails after exposed to 50 mg/kg of NBFRs were observed under a scanning electron microscope, indicating that shrinkage, tissue hyperplasia and perforation occurred on the visceral surface. Such damage might be related to the accumulation of more pollutants in mudsnails viscera. As one of the few studies to explore the biological process of NBFRs, our observation could provide a scientific basis for evaluating the environmental risks of NBFRs to benthic organisms.


Assuntos
Retardadores de Chama/análise , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Água
20.
J Chromatogr A ; 1623: 461200, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505289

RESUMO

Selectivity and high throughput are important for determination of trace level of various organophosphate flame retardants (OPFRs) in environmental matrices. In this work, three selective monolithic fibers for solid phase microextraction (SPME) were prepared and evaluated. They are graphene oxide (GO)-based surface trimethyl phosphate (TMP) imprinted polymeric fiber (GO/TMP-IPF), GO-based surface tri (2-chloroethyl) phosphate (TCEP) imprinted polymeric fiber (GO/TCEP-IPF) and GO-based surface triphenyl phosphate (TPhP) imprinted polymeric fiber (GO/TPhP-IPF). The imprinting factors of GO/TMP-IPF for TMP, GO/TECP-IPF for TCEP and GO/TPhP-IPF for TPhP were tested as high as 4.3, 4.5, 10.3, respectively. The three fibers were bound to a stainless steel wire to assemble a GO-based surface molecularly imprinted polymeric fiber array (GO/MIP-FA). GO/MIP-FA-SPME device was coupled to gas chromatography-flame photometric detector and carried out simultaneous determination of TMP, TCEP and TPhP in environmental water. Under the optimal conditions, ultralow limits of quantification (1.7 ng L-1-5.0 ng L-1); linearity (>0.99); intra- and inter-day precision expressed as relative standard deviations for an array in the range of 4.9-8.6% and 5.8-8.2%, respectively, and array-to-array reproducibility in the range of 7.2-9.1% were obtained. The GO/MIP-FA-SPME technique was successfully applied for the determination of OPFRs in various environmental water samples, and the relative recoveries were found to be in the range from 72.4 to 112.0%.


Assuntos
Retardadores de Chama/análise , Grafite/química , Impressão Molecular/métodos , Organofosfatos/análise , Polímeros/química , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Resíduos Industriais/análise , Cinética , Reprodutibilidade dos Testes , Temperatura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA