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1.
Environ Sci Technol ; 57(32): 11903-11912, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37506302

RESUMO

For the past few years, short-lived unsaturated halocarbons have been marketed as environmentally friendly replacements for long-lived halogenated greenhouse gases and ozone-depleting substances. The phase-in of unsaturated halocarbons for various applications, such as refrigeration and foam blowing, can be tracked by their emergence and increase in the atmosphere. We present the first atmospheric measurements of the hydrofluoroolefin (HFO) HFO-1336mzz(Z) ((Z)-1,1,1,4,4,4-hexafluoro-2-butene, cis-CF3CH═CHCF3), a newly used unsaturated hydrofluorocarbon. HFO-1336mzz(Z) has been detected in >90% of all measurements since 2018 during multi-month campaigns at three Swiss and one Dutch location. Since 2019, it is found in ∼30% of all measurements that run continuously at the Swiss high-altitude Jungfraujoch station. During pollution events, mole fractions of up to ∼10 ppt were observed. Based on our measurements, Swiss and Dutch emissions were estimated at 2-7 Mg yr-1 (2019-2021) and 30 Mg yr-1 (2022), respectively. Modeled spatial emission distributions only partly conform to population density in both countries. Monitoring the presence of new unsaturated halocarbons in the atmosphere is crucial since long-term effects of their degradation products are still debated. Furthermore, the production of HFOs involves climate-active substances, which may leak to the atmosphere─in the case of HFO-1336mzz(Z), for example, the ozone-depleting CFC-113a (CF3CCl3).


Assuntos
Gases de Efeito Estufa , Hidrocarbonetos Halogenados , Ozônio , Hidrocarbonetos Halogenados/análise , Monitoramento Ambiental , Atmosfera
2.
Sci Total Environ ; 862: 160504, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36464056

RESUMO

Despite being regulated globally for almost three decades, halocarbon continues to play a vital role in climate change and ozone layer because of its long lifetime in the ambient air. In recent years, unexpected halocarbon emissions have been found in Asia, raising concerns about ozone recovery. As a number of studies focused on halocarbon variations and source profiles, there is an increasing need to identify halocarbon source origins. In this study, an eight-month regular air sampling was conducted at a coastal site in Hong Kong from November 2020 to June 2021, and seventeen halocarbon species were selected for extensive investigation after advanced sample analysis in our laboratory. The temporal variations of halocarbon mixing ratio enhancements were analyzed, and the spatial variations of source origins were investigated by wind sectors and backward trajectory statistics. Our results indicate lower enhancements beyond the background values for major regulated CFCs and CCl4 than later controlled HCFCs and HFCs, suggesting the greater progress of Montreal Protocol implementation for the former species. The notable high enhancement values of non-regulated halocarbons from the north direction indicate their widespread usage in China. The source apportionment analysis estimates the contributions from six emission sectors on measured halocarbons, including solvent usage (43.57 ± 4.08 %), refrigerant residues (17.05 ± 5.71 %), cleaning agent/chemical production (13.18 ± 4.76 %), refrigerant replacements (13.06 ± 2.13 %), solvent residues (8.65 ± 3.28 %), and foaming agent (4.49 ± 1.08 %). Trajectories statistical analysis suggests that industrial solvent was mainly contributed by eastern China (i.e., Shandong and YRD), cleaning agent/chemical production was spread over southeast China (i.e., YRD and Fujian), and refrigeration replacements were dominant in Hong Kong surrounding regions. This work provides insight into the progress made in implementing the Montreal Protocol in Hong Kong and the surrounding region and the importance of continuous emission control.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Halogenados , Hidrocarbonetos Halogenados/análise , Hong Kong , Poluentes Atmosféricos/análise , China , Solventes/análise , Monitoramento Ambiental/métodos , Emissões de Veículos/análise
3.
Huan Jing Ke Xue ; 43(10): 4357-4366, 2022 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-36224122

RESUMO

Volatile organic compound (VOCs) emissions from poultry and livestock facilities affect the surrounding environmental quality and human health. However, VOCs emissions from broiler houses have been less characterized, and studies of related dominant odorants, carcinogenic risk, and ozone formation potential are still lacking. To fill this research gap, VOCs pollutants emitted from a broiler house were investigated in this study. The VOCs emission characteristics of the broiler house during three different periods of broiler growth (early, middle, and later) were analyzed using gas chromatography-mass spectrometry. The results showed that 77 types of VOCs were detected, including 16 types of halogenated hydrocarbons, 21 types of alkanes, 5 types of olefins, 12 types of aromatic hydrocarbons, 15 types of oxygenated volatile organic compounds (OVOCs), and 8 types of sulfides. During the entire 42-day growth period, the concentrations of halogenated hydrocarbons, alkanes, olefin, aromatic hydrocarbons, and OVOCs in the broiler house showed few changes. However, with the growth of broilers, the intake of sulfur-containing amino acids and the fecal emission coefficient increased, resulting in the gradual conversion of the VOCs to sulfide. Therefore, emissions of sulfur-containing VOCs increased in the early and middle growth periods. Moreover, the increase in ventilation in the house during the later growth period resulted in a decrease in the sulfur-containing VOCs concentrations. The dominant odorants in the broiler house were naphthalene, ethyl acetate, acetaldehyde, carbon disulfide, dimethyl disulfide, methanethiol, methanethiol, and thiophene. Methanethiol had the highest odorous values, ranging from 2172.4 to 19090.9. Meanwhile, there were acceptable levels of carcinogenic risk in the early and middle growth periods, with a lifetime cancer risk (LCR) of 7.7×10-6 and 4.5×10-6, respectively. The average ozone formation potential (OFP) was (1458.9±787.4) µg·m-3. The results of this study can provide a scientific basis for the monitoring of malodorous substances and formulation of emission reduction strategies in broiler production.


Assuntos
Poluentes Atmosféricos , Dissulfeto de Carbono , Hidrocarbonetos Aromáticos , Hidrocarbonetos Halogenados , Ozônio , Compostos Orgânicos Voláteis , Acetaldeído/análise , Poluentes Atmosféricos/análise , Alcanos/análise , Alcenos/análise , Aminoácidos , Animais , Dissulfeto de Carbono/análise , Galinhas , China , Monitoramento Ambiental , Humanos , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Halogenados/análise , Naftalenos , Ozônio/análise , Compostos de Sulfidrila , Enxofre/análise , Tiofenos/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
4.
Environ Pollut ; 304: 119244, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35378200

RESUMO

The oceanic production and release of volatile halocarbons (VHCs) to the atmosphere play a vital role in regulating the global climate. In this study, seasonal and spatial variations in VHCs, including trichlorofluoromethane (CFC-11), methyl iodide (CH3I), dibromomethane (CH2Br2), and bromoform (CHBr3), and environmental parameters affecting their concentrations were characterized in the atmosphere and seawater of the Yangtze River Estuary and its adjacent marine area during two cruises from October 17 to October 26, 2019 and from May 12 to May 25, 2020. Significant seasonal variations were observed in the atmosphere and seawater because of seasonal differences in the prevalent monsoon, water mass (Yangtze River Diluted Water), and biogenic production. VHCs concentrations were positively correlated with Chl-a concentrations in the surface water during autumn. The average sea-to-air fluxes of CH3I, CH2Br2, and CHBr3 in autumn were 19.7, 4.0, and 7.6 nmol m-2 d-1, respectively, while those in spring were 6.3, 6.4, and -3.6 nmol m-2 d-1. In the ship-based incubation experiments, ocean acidification and dust deposition had no significant effects on VHCs concentrations. The concentrations of CH2Br2 and CHBr3 were significantly positively correlated with phytoplankton biomass under lower pH condition (M3: pH 7.9). This result indicated that CH2Br2 and CHBr3 concentrations were mainly related to the biological release.


Assuntos
Estuários , Hidrocarbonetos Halogenados , China , Monitoramento Ambiental , Hidrocarbonetos Halogenados/análise , Concentração de Íons de Hidrogênio , Rios/química , Estações do Ano , Água do Mar/química , Água
5.
Sci Total Environ ; 830: 154667, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35314219

RESUMO

During chlorination of seawater, the presence of bromide and ammonia alters the speciation of the oxidant and lead to the formation of chlorinated and brominated amines. This can affect the effectiveness of the disinfection treatment and the formation of disinfection by-products released to the environment. In this study, a Membrane Introduction Mass Spectrometry (MIMS) analytical method was developed to differentiate brominated trihalamines (i.e. tribromamine NBr3, dibromochloramine NBr2Cl and bromodichloramine NBrCl2) in synthetic and natural chlorinated seawater. A mass-to-charge ratio of m/z = 253 corresponding to the parent ion was used for the quantification of NBr3 in absence of organic matter and the signal of the fragment at m/z = 177 was chosen in presence of high concentration of organic matter. Limits of detection were 0.23 µM (49 µg Cl2/L) and 0.18 µM (38 µg Cl2/L) for m/z 253 and m/z 177, respectively. Both NBr2Cl and NBrCl2 were monitored in chlorinated seawaters with their respective parent ion at m/z = 207 and m/z = 163 but were not quantified. MIMS results also showed that reaction of brominated trihalamines with natural organic matter (NOM) was a minor pathway for 1-2 mg C/L compared to their auto-decomposition in natural or synthetic seawater. Overall, MIMS was able to unambiguously differentiate and monitor brominated trihalamines for the first time in chlorinated seawater, which was not possible by using UV measurement, titration and colorimetric methods.


Assuntos
Desinfetantes , Hidrocarbonetos Halogenados , Poluentes Químicos da Água , Purificação da Água , Aminas , Desinfecção/métodos , Halogenação , Hidrocarbonetos Halogenados/análise , Espectrometria de Massas , Água do Mar , Poluentes Químicos da Água/análise , Purificação da Água/métodos
6.
Environ Sci Pollut Res Int ; 29(28): 43004-43018, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35094283

RESUMO

Volatile halogenated hydrocarbons (VHCs) attracted many attentions due to its toxicity and persistence in the environment. In this research, a novel in situ ecological restoration reactor was applied to the degradation of VHCs in polluted river water. The optimized working condition adaptation of the in situ restoration technique was evaluated through orthogonal tests. The experiments showed that when the water depth was 0.4 m, the HRT was 5 days, and the current velocity was 1 m/s, the optimal removal efficiency of VHCs in the reactor was achieved. And the removal rates of CHCl3, CCl4, C2HCl3, and C2Cl4 reached 70.27%, 70.59%, 67.74%, and 81.82%, respectively. The results showed that both HRT and water depth were significantly related to the removal efficiency of reactor. The physiological state of the plants was analyzed by fitting rapid light curve (RLC) model, which showed that the accumulation of VHCs inhibited the photosynthetic performance of plants. Moreover, the microbial community structures of fillers were tested by high-throughput sequencing, and the findings supported that the microbial community made a great response to adapt to the changes in environment of the reactor. The relative abundance of Rhodocyclaceae increased slightly, which hinted that it had good adaptability to VHCs in polluted river water. The research results confirmed that in situ ecological restoration reactor was a potential approach for removal VHCs in polluted river water.


Assuntos
Hidrocarbonetos Halogenados , Microbiota , Fluorescência , Hidrocarbonetos Halogenados/análise , Rios , Água
7.
Sci Rep ; 11(1): 13188, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162914

RESUMO

CVD 103-HgR live, attenuated oral cholera vaccine strain is indicated for single dose immunization against Vibrio cholerae, the causative agent for cholera. The vaccine packets containing buffer powder and lyophilized CVD 103-HgR are reconstituted in water and consumed. Studies were performed to explore the viability of CVD 103-HgR in drinking waters from common sources. CVD 103-HgR vaccine was reconstituted in bottled and tap waters from the United States and Europe, and viability was measured via colony forming units assay. Chemical analysis of select water samples was used to identify chemicals that have a negative effect on CVD 103-HgR viability. CVD 103-HgR titers were stable in all bottled waters tested, including purified bottled water, bottled spring water, and sparkling waters. However, tap water from certain cities in the US and Europe affected viability and are not compatible with vaccine. Water chemistry revealed that these tap waters contained copper, likely leached from copper plumbing. These studies give high confidence in the stability of CVD 103-HgR reconstituted in a variety of bottled waters. Waters containing copper, including tap water, should not be used to reconstitute CVD 103-HgR strain oral vaccine due to the common use of copper plumbing.


Assuntos
Vacinas contra Cólera , Água Potável/microbiologia , Vibrio cholerae/fisiologia , Carga Bacteriana , Cloro/análise , Cobre/análise , Água Potável/química , Europa (Continente) , Fluoretos/análise , Hidrocarbonetos Halogenados/análise , Engenharia Sanitária , Trialometanos/análise , Estados Unidos , Vacinas Atenuadas , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/isolamento & purificação , Purificação da Água
8.
Environ Pollut ; 284: 117190, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062437

RESUMO

Due to the characteristics of ozone-depleting and high global warming potential, chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) have been restricted by the Montreal Protocol and its amendments over the world. Considering that China is one of the main contributors to the emission of halocarbons, a long-term atmospheric observation on major substances including CFC-11 (CCl3F), CFC-12 (CCl2F2), HCFC-22 (CHClF2), HCFC-141b (CH3CCl2F), HCFC-142b (CH3CClF2) and HFC-134a (CH2FCF3) was conducted in five cities (Beijing, Hangzhou, Guangzhou, Lanzhou and Chengdu) of China during 2009-2019. The atmospheric concentrations of CFC-11, CFC-12, HCFC-141b and HCFC-142b all showed declining trends on the whole while those of HCFC-22 and HFC-134a were opposite. A paired sample t-test showed that the ambient mixing ratios of HCFC-22 and HFC-134a in cities were 41.9% and 25.7% higher on average than those in suburban areas, respectively, while the other substances did not show significant regional differences. The annual emissions of halocarbons were calculated using an interspecies correlation method and the results were generally consistent with the published estimates. Discrepancies between bottom-up inventories and the estimates in this study for CFCs emissions were found. Among the most consumed ozone depleting substances (ODSs) in China, CFCs accounted for 75.1% of the ozone depletion potential (ODP)-weighted emissions while HCFCs contributed a larger proportion (58.6%) of CO2-equivalent emissions in 2019. China's emissions of HCFC-141b and HCFC-142b contributed the most to the global emission (17.8%-48.0%). The elimination of HCFCs in China will have a crucial impact on the HCFCs phase-out in the world.


Assuntos
Hidrocarbonetos Halogenados , Pequim , China , Clorofluorcarbonetos/análise , Aquecimento Global , Hidrocarbonetos Halogenados/análise
9.
Ecotoxicol Environ Saf ; 203: 110945, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32684517

RESUMO

The high-concentration wastewater produced in the industrial reverse osmosis (RO) process contains a large amount of refractory organic matters, which will have serious impacts on the natural environment and human health. Among them, contaminants can be transformed by humus-reducing bacteria based on humus. In this study, O3- assisted UV-Fenton method was applied as pretreatment. Biological activated carbon (BAC) technology in which humus-reducing bacteria were the dominant bacteria, enhanced by electron donor and Fe3+, was used to dispose of RO concentrate (ROC). The results showed that water treatment process combining oxidation with biological filtration had a positive effect on the removal of stubborn contaminants in ROC. The system was strengthened by adding electron donor and Fe3+, and the chemical oxygen demand (COD) removal efficiency was up to 80.1%. However, when the removal efficiency of UV254 absorbing pollutants reached optimal value (87.3%), that means only Fe3+ was added.


Assuntos
Carvão Vegetal/análise , Compostos Férricos/química , Substâncias Húmicas , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Filtração/métodos , Substâncias Húmicas/análise , Substâncias Húmicas/microbiologia , Hidrocarbonetos Halogenados/análise , Peróxido de Hidrogênio/química , Ferro/química , Osmose , Oxirredução , Ozônio/química , Raios Ultravioleta , Águas Residuárias/análise , Águas Residuárias/microbiologia
10.
J Agric Food Chem ; 68(22): 6084-6091, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32378893

RESUMO

Halogenated natural products (HNPs) and persistent organic pollutants (POPs) were quantified in South African sardines (Sardinops sagax) from one site in the South Atlantic Ocean and one in the Indian Ocean. At both sites, HNPs [2,3,3',4,4',5,5'-heptachloro-1'-methyl-1,2'-bipyrrole (Q1), mixed halogenated compound 1 (MHC-1), 2,4,6-tribromoanisole (2,4,6-TBA), 2'-MeO-BDE 68 (BC-2), and 6-MeO-BDE 47 (BC-3)] were 1 order of magnitude higher concentrated than anthropogenic POPs [mainly polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT), ∼3 ng/g lipids]. MHC-1 and Q1 were the major HNPs in the samples from both sites, contributing with up to 49 and 52 ng/g lipids, respectively. The same 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDE)/PCB ratio suggested that the major POPs were evenly distributed at both sites. Different ratios of Q1/MHC-1 in the samples from the Indian (∼2:1) and South Atlantic (∼1:1) Oceans indicated that the occurrence of HNPs in seafood is difficult to predict and should be investigated more in detail. The PCB levels in sardines were found to pose no risk to human consumers, whereas HNPs could not be evaluated because of the lack of toxicological data.


Assuntos
Peixes/metabolismo , Contaminação de Alimentos/análise , Hidrocarbonetos Halogenados/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Oceano Atlântico , Hidrocarbonetos Halogenados/metabolismo , Oceano Índico , Poluentes Químicos da Água/metabolismo
11.
Ecotoxicol Environ Saf ; 191: 110212, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32006868

RESUMO

Since many household products used by individuals contain flame retardants (FRs), there is more chance that these chemicals may be present in the various exhibit of the indoor environment. Despite being one of the fastest-growing economies worldwide, the contamination level, sources, products, and pathways of FRs in India, is either not known or limited. This inspired us to investigate the level, profile, spatial distribution, and sources of different classes of FRs in the indoor air. For this purpose, 15 brominated, 2 chlorinated, and 8 organophosphate FRs (OPFRs) were investigated in indoor air samples from urban and suburban sites of an Indian state of Bihar. Additionally, inhalation health risk exposure to children and the adult was estimated to predict the risk of these chemicals. Overall, ∑8OPFRs (median 351 pg/m3) was the most prominent in air, followed by novel brominated FR (∑6NBFRs) (median 278 pg/m3), polybrominated diphenyl ether (∑9PBDE) (median 5.05 pg/m3), and dechlorane plus (∑2DPs) (median 2.52 pg/m3), and accounted for 55%, 44%, 0.8% and 0.4% of ∑FRs, respectively. Generally, ∑9PBDEs (median 6.29 pg/m3) and ∑8OPFRs (median 355 pg/m3) were measured high at sub-urban sites, while urban sites had the highest level of ∑2DPs (median 2.81 pg/m3) and ∑6NBFRs (median 740 pg/m3). BDE-209 was most abundant among ∑9PBDEs, while syn-DP dominated in ∑2DPs. Likewise, DBDPE was most prevalent in ∑6NBFRs, while TMPP topped among ∑8OPFRs. The principal component analysis revealed contribution from household items, food packaging and paints, hydraulic fluid, a gasoline additive, and de-bromination of BDE-209 as the primary sources of FRs. The estimated daily inhalation exposure (DIE) indicated a relatively high risk to children than the adult. The DIE of individual FR was several folds lower than their corresponding oral reference dose (RfDs), suggesting minimal risk. However, exposure risk, especially to children, may still need attention because other routes of intake may always be significant in the case of Bihar.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Retardadores de Chama/análise , Hidrocarbonetos Halogenados/análise , Exposição por Inalação/análise , Organofosfatos/análise , Humanos , Hidrocarbonetos Halogenados/química , Índia , Organofosfatos/química , Análise de Componente Principal , Medição de Risco
12.
Work ; 65(2): 377-390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31985480

RESUMO

BACKGROUND: The aim of this study was to characterize solid particulate aerosol derived from a cutlery microenterprise and to investigate substances associated with activities performed within the work environment. OBJECTIVE: Suspended particulate matter (SPM) was collected at different locations in the cutlery workshop and near machines used by workers, using passive sampling devices fitted with polytetrafluoroethylene filters, onto which total particulate material was deposited. The substances present in the SPM were analyzed using gas chromatography-mass spectrometry (GC-MS). RESULTS: Identification of the substances was performed using the National Institute of Standards (NIST) library and automated mass spectral deconvolution and identification system. (AMDIS) software, considering at least 70% probability. The concentration of total dust, obtained using a gravimetric method, was approximately 1 mg.m-3. CONCLUSION: The toxic substances found in the SPM included halogenated hydrocarbons (containing chlorine, fluorine, and iodine) and aromatic hydrocarbons. The toxic substances included naphthalene, which is classified as carcinogenic.


Assuntos
Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Halogenados/análise , Material Particulado/análise , Poluentes Ocupacionais do Ar/análise , Brasil , Cromatografia Gasosa-Espectrometria de Massas , Utensílios Domésticos , Naftalenos/análise , Empresa de Pequeno Porte
13.
Ann Pharm Fr ; 78(1): 34-41, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31796267

RESUMO

BACKGROUND: The effect of oxygen on markers of oxidative stress has not been totally elucidated because previous studies have yielded conflicting results. METHODS: A method for the collection and gas chromatography-mass spectrometry of the halogenated volatile organic compounds in human alveolar breath is described. A transportable apparatus sampled specifically alveolar breath; the volatile organic compounds were captured in a thermal desorption tube, Carbotrap 200®. The sample was thermally desorbed from the trap in an automated gas chromatography with mass spectrometry detection and peak fragmentation. Compounds were identified by reference to a computer-based library of mass spectra. RESULTS: Trichlorotrifluoroethane, tetrafluoroethane, dichlorodifluoromethane were identified in alveolar breath of healthy volunteers after mental exercise-induced oxidative stress. The effects of halogenated alkanes were investigated on electron transport chain activity. These agents impaired the NADH oxidation suggesting an inhibition of the complex I (NADH: ubiquinone oxidoreductase) of the electron transport chain. These inhibitory effects are suspected likely to fight against oxidative stress deleterious reactions. CONCLUSION: Chemical inhibition of the oxidative burst in human body trough these halogenated inhibitors is a new concept of significant practical, medical, biological and scientific interest.


Assuntos
Testes Respiratórios/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Halogenados/análise , Estresse Oxidativo , Alvéolos Pulmonares/metabolismo , Pensamento , Compostos Orgânicos Voláteis/análise , Alcanos/análise , Testes Respiratórios/instrumentação , Complexo I de Transporte de Elétrons/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Mitocôndrias/metabolismo , Células U937
14.
J Breath Res ; 14(2): 026004, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31796655

RESUMO

Post-operative isoflurane has been observed to be present in the end-tidal breath of patients who have undergone major surgery, for several weeks after the surgical procedures. A major new non-controlled, non-randomized, and open-label approved study will recruit patients undergoing various surgeries under different inhalation anaesthetics, with two key objectives, namely (1) to record the washout characteristics following surgery, and (2) to investigate the influence of a patient's health and the duration and type of surgery on elimination. In preparation for this breath study using proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS), it is important to identify first the analytical product ions that need to be monitored and under what operating conditions. In this first paper of this new research programme, we present extensive PTR-TOF-MS studies of three major anaesthetics used worldwide, desflurane (CF3CHFOCHF2), sevoflurane ((CF3)2CHOCH2F), and isoflurane (CF3CHClOCHF2) and a fourth one, which is used less extensively, enflurane (CHF2OCF2CHFCl), but is of interest because it is an isomer of isoflurane. Product ions are identified as a function of reduced electric field (E/N) over the range of approximately 80 Td to 210 Td, and the effects of operating the drift tube under 'normal' or 'humid' conditions on the intensities of the product ions are presented. To aid in the analyses, density functional theory (DFT) calculations of the proton affinities and the gas-phase basicities of the anaesthetics have been determined. Calculated energies for the ion-molecule reaction pathways leading to key product ions, identified as ideal for monitoring the inhalation anaesthetics in breath with a high sensitivity and selectivity, are also presented.


Assuntos
Anestésicos Inalatórios/análise , Testes Respiratórios/métodos , Hidrocarbonetos Halogenados/análise , Espectrometria de Massas/métodos , Prótons , Compostos Orgânicos Voláteis/análise , Teoria da Densidade Funcional , Desflurano/análise , Eletricidade , Feminino , Humanos , Íons , Isoflurano/análise , Masculino , Sevoflurano/análise , Processamento de Sinais Assistido por Computador
15.
Chemosphere ; 233: 890-895, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340416

RESUMO

The reduction of halocarbons by NADH models and NADH under ambient conditions is reported as a new type of reactivity pointing towards a hitherto unknown disruptive pathway for NADH/NADPH-dependent processes. The reaction was studied with the omnipresent pesticide DDT, the inhalation anesthetic halothane, and several simple halocarbons. The halide-hydride exchange represents a biochemical equivalent for the reduction of halocarbons by traditional synthetic reagents like silanes (R3Si-H) and stannanes (R3Sn-H). High precision thermochemical calculations (CBS-QB3) reveal the carbon-hydrogen bond dissociation energy of NADH (70.8 kcal·mol-1) to be lower than that of stannane (SnH4: 78.1 kcal·mol-1), approaching that of the elusive plumbane (PbH4: 68.9 kcal·mol-1). The ready synthetic accessibility of NADH models, their low carbon-hydrogen bond dissociation energy, and their dehalogenation activity in the presence of air and moisture recommend these compounds as substitutes for the air-sensitive or toxic metal hydrides currently employed in synthesis.


Assuntos
DDT/metabolismo , Poluentes Ambientais/metabolismo , Recuperação e Remediação Ambiental/métodos , Halotano/metabolismo , Hidrocarbonetos Halogenados/análise , Hidrocarbonetos Halogenados/metabolismo , NAD/metabolismo , Carbono/química , Hidrogênio/química , Ligação de Hidrogênio , Indicadores e Reagentes , Silanos/química , Compostos de Estanho/química
16.
Ecotoxicol Environ Saf ; 182: 109470, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31352212

RESUMO

In the past few years, polyhalogenated carbazoles (PHCZs) have been of increasing concern because their structure is similar to that of legacy POPs. In the present study, an analytical method, including intensive cleanup and fractionation procedures in combination with instrumental parameters, was developed to determine ultratrace polyhalogenated carbazoles (PHCZs) in soil and sediment. The eluting sorbents, volume and packing of the column were optimized. Our results showed that 5 g of florisil and 4 g of silica gel under 150 mL of hexane/DCM = 3:1 presented good performance in terms of recovery and repeatability. GC-HRMS, GC-MS/MS (EI-MRM) and GC-MS (EI-SIM) were applied to compare the performance of PHCZ analysis. For sensitivity, EI-MRM presents method detection limits comparable to those of GC-HRMS and much lower than those of EI-SIM. Regarding selectivity, GC-HRMS performed better than the other two techniques since GC-HRMS can reduce interference from perfluorokerosene (PFK) and DDX (DDT, DDE, and DDD) due to its high resolution. GC-HRMS was then further optimized by shortening the run time and modifying the SIM ion. The final method was successfully applied to determine PHCZs in soil and sediment, and the target compounds had almost 100% detection frequency in the samples. The ubiquitous presence of PHCZ in soil and sediment calls for a further investigation of its source, distribution and degradation in the environment.


Assuntos
Carbazóis/análise , Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/química , Hidrocarbonetos Halogenados/análise , Poluentes do Solo/análise , Solo/química , Cromatografia Gasosa-Espectrometria de Massas , Hexanos/química , Limite de Detecção , Silicatos de Magnésio/química , Dióxido de Silício/química , Espectrometria de Massas em Tandem
17.
Artigo em Inglês | MEDLINE | ID: mdl-31192775

RESUMO

The exposure to several compounds such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), organophosphorus pesticides (OPs), polycyclic aromatic hydrocarbon (PAHs), perfluoroalkyl substances (PFASs) and polybrominated diphenyl ethers (PBDEs) is a public health issue. The European Union (EU) recommended that its member states monitor the presence of emerging contaminants, like PBDEs and PFASs, in food and in the environment to obtain an accurate estimation of exposure. The tissues of wild animals exposed to these compounds can represent a suitable indicator of environmental pollution. The aim of this work is to evaluate: (i) the occurrence of PCBs, PBDEs, PFASs, PAHs, OCPs and OPs in four game animals' meat (chamois, red deer, wild boar and roe deer); (ii) interspecies differences and (iii) human exposure. Muscle samples from seventy-nine animals were collected during the hunting season in a Northern Italy mountain area at altitudes ranging from 300 to 2500 meters above sea level. The analyses were performed with gas chromatography-mass spectrometry (GC-MS/MS) and ultra-performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS). No PBDEs were found in the samples. OCPs, OPs and PCBs were detected in almost all samples at different concentration ranges, showing higher frequency in ungulate species than in wild boar. PFAs were found only in wild boar. Anthracene and benzopyrene, among PAHs, were found only in chamois, at low concentrations. The lack of an accurate pattern of exposure as well as variable consumption by hunters does not allow accurate risk characterisation. However, a low risk for consumers can be indicated due to the frequent detection of contaminants only at trace levels, the scarce prevalence of high concentrations of some contaminants and the low consumption of game animal meat. In conclusion, the organisation of a control plan on residues in game animals would be advisable.


Assuntos
Animais Selvagens , Hidrocarbonetos Halogenados/análise , Inseticidas/análise , Carne/análise , Compostos Organofosforados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Cromatografia Líquida de Alta Pressão , Itália , Especificidade da Espécie , Espectrometria de Massas em Tandem
18.
Sci Total Environ ; 659: 561-567, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096385

RESUMO

Severe pollution of organohalogen compounds (OHCs) including PBDEs, PCBs and DDTs is demonstrated in e-waste recycling sites and metropolis in South China, but relatively little is known of their impacts on wildlife that inhabits nature reserves in this region, especially those located at the neighborhood areas of e-waste recycling sites. In the present study, PBDEs, PCBs and DDTs as well as liver histological changes were examined in common kingfisher breeding at a nature reserve (Shimentai National Nature Reserve, SNNR) near a notorious e-waste recycling site in South China. Mean ∑PBDEs (84.9 ng/g lipid weight), ∑PCBs (397 ng/g) and ∑TEQs (total toxic equivalent of coplanar PCBs, 2.68 ng/g) concentrations in kingfishers from SNNR were approximately 2-, 5-, and 4-fold higher than those detected in a reference population, respectively; suggesting contamination of the e-waste-derived OHCs in SNNR. Mean ∑DDTs concentration (2150 ng/g) in kingfishers from SNNR was also higher (~2-fold) than that from the reference samples. While ∑DDTs dominated the composition of the OHCs at both sampling sites, ∑PCBs was also important in kingfishers from SNNR, averaging 15% of ∑OHCs. Histological examination of the liver showed steatosis occurred in 60% of the kingfishers from SNNR. Birds with hepatic steatosis had significantly (p = 0.03) higher ∑TEQs than those without steatosis. Similar trends were also found for ∑PCBs and ∑DDTs, although it is not statistically significant. It therefore seems likely that the hepatic steatosis were associated with the relatively high body-burden of OHCs, although the possibility of other factors resulting in hepatic steatosis cannot be ruled out.


Assuntos
Aves , Resíduo Eletrônico , Monitoramento Ambiental , Fígado Gorduroso/veterinária , Hidrocarbonetos Halogenados/análise , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Animais , China , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/patologia , Reciclagem , Estações do Ano
19.
Environ Sci Pollut Res Int ; 26(18): 18583-18592, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31054055

RESUMO

Trihalomethanes (THMs) and adsorbable organic halides (AOX) were generated in chlorinated water. The purpose of the study was to provide a comprehensive picture of concentration distribution, the seasonal and different water source variability of THMs and AOX. Data for THMs, AOX, and other physico-chemical parameters were from 538 samples of 16 drinking water work through a 3-year sampling program which was conducted in Shandong province with typical temperate and monsoonal climate. Selected samples were considered with the influence of factors such as season, water source, and disinfectant. The THMs and AOX concentration of the samples disinfected with chlorine ranged from 2.1-105 µg/L and 11-238 µg/L, respectively. The THMs and AOX concentration of the samples disinfected chlorine dioxide ranged from N.D.-47.6 µg/L and N.D.-102 µg/L, respectively. The median concentration of THMs and AOX of samples disinfected with chlorine were 35 µg/L and 61 µg/L, much higher than chlorine dioxide, respectively. Ninety-two percent of the samples disinfected with chlorine and all samples disinfected with chlorine dioxide met Chinese drinking water standard for THMs. The ratio of tribromethane (TBM) to THMs of samples disinfected with chlorine was 19%, lower than chlorine dioxide 42%. Bromine substitution factor (BSF) of THMs and initial concentration of bromide showed weak correlation, and the Spearman correlation coefficient was 0.38. THMs and AOX concentrations showed noticeable seasonal variations with the highest median concentrations in spring. The levels of THMs and AOX in drinking water varied with different water sources and followed the order local reservoir > Yellow River reservoir > ground water. The survey results complement the database of THMs and AOX occurrence in drinking water in China, and offer a significant reference data for setting disinfections by-products occurrence in countries or regions with similar climate around the world.


Assuntos
Água Potável/química , Hidrocarbonetos Halogenados/análise , Poluentes Químicos da Água/análise , China , Desinfetantes/química , Água Potável/análise , Água Potável/normas , Água Doce/análise , Água Doce/química , Halogenação , Estações do Ano , Trialometanos/análise , Trialometanos/normas , Purificação da Água/métodos
20.
Ecotoxicol Environ Saf ; 180: 668-678, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146153

RESUMO

Persistent organic pollutants (POPs) are highly toxic organic chemicals. Lakes are one of the main sinks of POPs. POPs can be accumulated in multiple matrices in lake ecosystems and biomagnified through the food web, and thus pose a potential threat not only to lake ecosystems, but also to human health. Given their potential persistent risks, they have received much attention over the past decades. This review comprehensively summarizes the data on the levels and distributions of POPs in selected typical lake ecosystems in China and worldwide, involving water, sediments, organisms, and surrounding soils and atmosphere. It was found that current publications on POPs in Chinese lakes are mainly related to lakes in the developed eastern plain area, with only a few studies concerning the less-developed Qinghai-Tibet Plateau area. Similarly, around the world, there are more research on POPs in developed countries and less in relatively less-developed areas. Moreover, there are significant differences in the levels of POPs in different matrices in different lake ecosystems. Legacy POPs, such as polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs), were commonly detected and reported in different lakes, while emerging POPs like perfluorinated compounds (PFCs), polychlorinated naphthalenes (PCNs), Tetrabromobisphenol A (TBBPA), and hexabromocyclododecane (HCBD) were relatively less detected or reported. A comprehensive summarization on the levels and distributions of traditional and emerging POPs in lake ecosystems could be significant for further understanding the behaviors and risks of POPs in lake ecosystems.


Assuntos
Ecossistema , Lagos/química , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/estatística & dados numéricos , Cadeia Alimentar , Sedimentos Geológicos/química , Humanos , Hidrocarbonetos Halogenados/análise
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