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1.
Environ Sci Technol ; 58(13): 5695-5704, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38502526

RESUMO

The limited research on volatile organic compounds (VOCs) has not taken into account the interactions between constituents. We used the weighted quantile sum (WQS) model and generalized linear model (GLM) to quantify the joint effects of ambient VOCs exposome and identify the substances that play key roles. For a 0 day lag, a quartile increase of WQS index for n-alkanes, iso/anti-alkanes, aromatic, halogenated aromatic hydrocarbons, halogenated saturated chain hydrocarbons, and halogenated unsaturated chain hydrocarbons were associated with 1.09% (95% CI: 0.13, 2.06%), 0.98% (95% CI: 0.22, 1.74%), 0.92% (95% CI: 0.14, 1.69%), 1.03% (95% CI: 0.14, 1.93%), 1.69% (95% CI: 0.48, 2.91%), and 1.85% (95% CI: 0.93, 2.79%) increase in cardiovascular disease (CVD) emergency hospital admissions, respectively. Independent effects of key substances on CVD-related emergency hospital admissions were also reported. In particular, an interquartile range increase in 1,1,1-trichloroethane, methylene chloride, styrene, and methylcyclohexane is associated with a greater risk of CVD-associated emergency hospital admissions [3.30% (95% CI: 1.93, 4.69%), 3.84% (95% CI: 1.21, 6.53%), 5.62% (95% CI: 1.35, 10.06%), 8.68% (95% CI: 3.74, 13.86%), respectively]. We found that even if ambient VOCs are present at a considerably low concentration, they can cause cardiovascular damage. This should prompt governments to establish and improve concentration standards for VOCs and their sources. At the same time, policies should be introduced to limit VOCs emission to protect public health.


Assuntos
Poluentes Atmosféricos , Doenças Cardiovasculares , Expossoma , Hidrocarbonetos Halogenados , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Doenças Cardiovasculares/epidemiologia , Hidrocarbonetos , Hospitais
2.
J Med Chem ; 67(5): 4063-4082, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38482827

RESUMO

Dengue is a global public health threat, with about half of the world's population at risk of contracting this mosquito-borne viral disease. Climate change, urbanization, and global travel accelerate the spread of dengue virus (DENV) to new areas, including southern parts of Europe and the US. Currently, no dengue-specific small-molecule antiviral for prophylaxis or treatment is available. Here, we report the discovery of JNJ-1802 as a potent, pan-serotype DENV inhibitor (EC50's ranging from 0.057 to 11 nM against the four DENV serotypes). The observed oral bioavailability of JNJ-1802 across preclinical species, its low clearance in human hepatocytes, the absence of major in vitro pharmacology safety alerts, and a dose-proportional increase in efficacy against DENV-2 infection in mice were all supportive of its selection as a development candidate against dengue. JNJ-1802 is being progressed in clinical studies for the prevention or treatment of dengue.


Assuntos
Vírus da Dengue , Dengue , Hidrocarbonetos Halogenados , Indóis , Camundongos , Humanos , Animais , Sorogrupo , Dengue/tratamento farmacológico
3.
Environ Sci Technol ; 57(49): 20781-20791, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38010203

RESUMO

Methyl halides play important roles in stratospheric ozone depletion, but their formation mechanisms are not well defined. This study demonstrated that iron-based photochemistry significantly enhanced alkyl halide production by promoting the reaction of the representative monomer of lignin with halide ions in saline water under solar light irradiation. The methyl chloride (CH3Cl) emission from the light/Fe(III) process was 2 orders of magnitude higher than dark treatment and in the absence of iron. In addition, bromide and iodide showed better reactivity in the formation of the corresponding methyl bromide (CH3Br) and methyl iodide (CH3I). Alkyl halides identified from seawater, brackish water, and salt pan water under sunlight irradiation were positively correlated with the Fe(III) concentrations, indicating that iron-based photochemistry is ubiquitous. This work suggested that the photoinduced formation of methyl radical and redox cycling of iron triggered by the Fenton-like reaction are responsible for the enhanced release of alkyl halides. This study represents an abiotic formation pathway of alkyl halides, which accounts for a portion of the unidentified sources of halocarbons in the ocean.


Assuntos
Hidrocarbonetos Halogenados , Ferro , Fotoquímica , Água do Mar , Compostos Férricos
4.
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
5.
J Med Chem ; 66(15): 10579-10603, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37496104

RESUMO

Novel 2-arylmethoxy-4-(2,2'-dihalogen-substituted biphenyl-3-ylmethoxy) benzylamine derivatives were designed, synthesized, and evaluated in vitro and in vivo against cancers as PD-1/PD-L1 inhibitors. Through the computer-aided structural optimization and the homogeneous time-resolved fluorescence (HTRF) assay, compound A56 was found to most strongly block the PD-1/PD-L1 interaction with an IC50 value of 2.4 ± 0.8 nM and showed the most potent activity. 1H NMR titration results indicated that A56 can tightly bind to the PD-L1 protein with KD < 1 µM. The X-ray diffraction data for the cocrystal structure of the A56/PD-L1 complex (3.5 Å) deciphered a novel binding mode in detail, which can account for its most potent inhibitory activity. Cell-based assays further demonstrated the strong ability of A56 as an hPD-1/hPD-L1 blocker. Especially in an hPD-L1 MC38 humanized mouse model, A56 significantly inhibited tumor growth without obvious toxicity, with a TGI rate of 55.20% (50 mg/kg, i.g.). In conclusion, A56 is a promising clinical candidate worthy of further development.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Animais , Camundongos , Antígeno B7-H1 , Benzilaminas/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Hidrocarbonetos Halogenados/química , Hidrocarbonetos Halogenados/farmacologia
6.
Nature ; 618(7967): 967-973, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37380694

RESUMO

Observational evidence shows the ubiquitous presence of ocean-emitted short-lived halogens in the global atmosphere1-3. Natural emissions of these chemical compounds have been anthropogenically amplified since pre-industrial times4-6, while, in addition, anthropogenic short-lived halocarbons are currently being emitted to the atmosphere7,8. Despite their widespread distribution in the atmosphere, the combined impact of these species on Earth's radiative balance remains unknown. Here we show that short-lived halogens exert a substantial indirect cooling effect at present (-0.13 ± 0.03 watts per square metre) that arises from halogen-mediated radiative perturbations of ozone (-0.24 ± 0.02 watts per square metre), compensated by those from methane (+0.09 ± 0.01 watts per square metre), aerosols (+0.03 ± 0.01 watts per square metre) and stratospheric water vapour (+0.011 ± 0.001 watts per square metre). Importantly, this substantial cooling effect has increased since 1750 by -0.05 ± 0.03 watts per square metre (61 per cent), driven by the anthropogenic amplification of natural halogen emissions, and is projected to change further (18-31 per cent by 2100) depending on climate warming projections and socioeconomic development. We conclude that the indirect radiative effect due to short-lived halogens should now be incorporated into climate models to provide a more realistic natural baseline of Earth's climate system.


Assuntos
Atmosfera , Mudança Climática , Modelos Climáticos , Clima , Temperatura Baixa , Halogênios , Atmosfera/análise , Atmosfera/química , Halogênios/análise , Hidrocarbonetos Halogenados , Oceanos e Mares , Água do Mar/análise , Água do Mar/química , Mudança Climática/estatística & dados numéricos , Atividades Humanas
7.
J Pharm Biomed Anal ; 234: 115525, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37320973

RESUMO

Gas chromatography-mass spectrometry (GC-MS) is the first choice for law enforcement agencies in various countries to analyze new psychoactive substances (NPS) because of its advantages and complete databases. For synthetic cathinone-type NPS (SCat), alkalization and extraction processes before GC-MS analysis are essential. However, the base form of SCat is unstable, causing it to quickly degrade in solution and cause pyrolysis at the GC-MS injection inlet. In this study, we investigated the degradation of ethyl acetate and pyrolysis at the GC-MS injection inlet of 2-fluoromethcathinone (2-FMC), the most unstable SCat. Using gas chromatography-quadruple/time-of-flight mass spectrometry (GC-Q/TOF-MS) combined with the predicted data from theoretical calculations and the analysis of mass spectrometry (MS) fragmentation, the structures of 15 2-FMC degradation and pyrolysis products were identified. Among them, 11 products were produced during degradation, and six products were obtained from pyrolysis (two of which were the same as the degradation products). At the same time, the degradation and pyrolysis pathways of 2-FMC were provided. The balance between keto-enol and enamine-imine tautomerism triggered the primary degradation pathway of 2-FMC. The subsequent degradation started from the tautomer with a hydroxyimine structure, including imine hydrolysis, oxidation, imine-enamine tautomerism, intramolecular ammonolysis of halobenzene, and hydration to generate a series of degradation products. The secondary degradation reaction was the ammonolysis of ethyl acetate to yield N-[1-(2'-fluorophenyl)-1-oxopropan-2-yl]-N-methylacetamide and the byproduct, N-[1-(2'-fluorophenyl)-1-oxopropan-2-yl]-N-methylformamide. In the pyrolysis of 2-FMC, the major reactions were dehydrogenation, intramolecular ammonolysis of halobenzene, and defluoromethane. The achievements of this manuscript not only study 2-FMC degradation and pyrolysis but also lay the foundation for the study of SCat stability and their accurate analysis by GC-MS.


Assuntos
Hidrocarbonetos Halogenados , Pirólise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas/métodos , Iminas
8.
J Med Chem ; 66(12): 8238-8250, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37294951

RESUMO

The reactivities of halido[1,3-diethyl-4,5-diphenyl-1H-imidazol-2-ylidene]gold(I) (chlorido (5), bromido (6), iodido (7)), bis[1,3-diethyl-4,5-diphenyl-1H-imidazol-2-ylidene]gold(I) (8), and bis[1,3-diethyl-4,5-diphenyl-1H-imidazol-2-ylidene]dihalidogold(III) (chlorido (9), bromido (10), iodido (11)) complexes against ingredients of the cell culture medium were analyzed by HPLC. The degradation in the RPMI 1640 medium was studied, too. Complex 6 quantitatively reacted with chloride to 5, while 7 showed additionally ligand scrambling to 8. Interactions with non-thiol containing amino acids could not be detected. However, glutathione (GSH) reacted immediately with 5 and 6 yielding the (NHC)gold(I)-GSH complex 12. The most active complex 8 was stable under in vitro conditions and strongly participated on the biological effects of 7. The gold(III) species 9-11 were completely reduced by GSH to 8 and are prodrugs. All complexes were tested for inhibitory effects in Cisplatin-resistant cells, as well as against cancer stem cell-enriched cell lines and showed excellent activity. Such compounds are of utmost interest for the therapy of drug-resistant tumors.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/química , Compostos de Bifenilo , Técnicas de Cultura de Células , Ouro/química , Hidrocarbonetos Halogenados/química
9.
Water Res ; 234: 119810, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889094

RESUMO

Halogenated organic pollutants are often found in wastewater effluent although it has been usually treated by advanced oxidation processes. Atomic hydrogen (H*)-mediated electrocatalytic dehalogenation, with an outperformed performance for breaking the strong carbon-halogen bonds, is of increasing significance for the efficient removal of halogenated organic compounds from water and wastewater. This review consolidates the recent advances in the electrocatalytic hydro-dehalogenation of toxic halogenated organic pollutants from contaminated water. The effect of the molecular structure (e.g., the number and type of halogens, electron-donating or electron-withdrawing groups) on dehalogenation reactivity is firstly predicted, revealing the nucleophilic properties of the existing halogenated organic pollutants. The specific contribution of the direct electron transfer and atomic hydrogen (H*)-mediated indirect electron transfer to dehalogenation efficiency has been established, aiming to better understand the dehalogenation mechanisms. The analyses of entropy and enthalpy illustrate that low pH has a lower energy barrier than that of high pH, facilitating the transformation from proton to H*. Furthermore, the quantitative relationship between dehalogenation efficiency and energy consumption shows an exponential increase of energy consumption for dehalogenation efficiency increasing from 90% to 100%. Lastly, challenges and perspectives are discussed for efficient dehalogenation and practical applications.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Halogenados , Poluentes Químicos da Água , Águas Residuárias , Halogênios/química , Água , Hidrogênio , Poluentes Químicos da Água/análise , Hidrocarbonetos Halogenados/química
10.
Med Pr ; 74(1): 53-62, 2023 Mar 08.
Artigo em Polonês | MEDLINE | ID: mdl-36857730

RESUMO

BACKGROUND: Chemical substances from the halogenated aliphatic hydrocarbons group are used in industry, e.g., as intermediates in syntheses, auxiliaries, solvents in degreasing processes, and laboratory tests. Due to their harmful effects on human health and the environment, their use is often banned or limited to certain industrial uses only. MATERIAL AND METHODS: A sorbent tube containing 2 layers (100/50 mg) of coconut shell charcoal was used as a sampler for air sampling. Gas chromatography-mass spectrometry technique and the use of HP-5MS column (30 m × 0.25 mm × 0.25 µm), an oven temperature ramp program from 40°C to 250°C and selected ion monitoring mode were chosen for the determination. RESULTS: The established chromatographic conditions enable the simultaneous determination of tetrachloromethane, trichlorethane, 1,1,2-trichloroethane and tetrachloroethene in the concentration range 2-100 µg/ml. The average desorption coefficients obtained were: 0.97 for tetrachloromethane, 0.96 for trichloroethene, 0.96 for 1,1,2-trichloroethane and 0.96 for tetrachloroethene. CONCLUSIONS: The calculation of the substance concentration in the analyzed air requires the determination of the amount of substances trapped by the sorbent tube, the desorption coefficient and the air sample volume. Adequate dilution of the extract makes it possible to determine tetrachloromethane, trichloroethene, 1,1,2-trichloroethane and tetrachloroethene in ranges corresponding to 0.1-2 times the maximum admissible concentrations in the workplace air. This article discusses the issues occupational safety and health, which are the subject matter of health sciences and environmental engineering research. Med Pr. 2023;74(1):53-62.


Assuntos
Hidrocarbonetos Halogenados , Tetracloroetileno , Tricloroetileno , Humanos , Tricloroetanos , Tetracloreto de Carbono , Local de Trabalho
11.
Waste Manag ; 160: 173-181, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36848761

RESUMO

Volatile organic compounds (VOCs) emission on the working face of a large sanitary landfill in northern China was characterized in a one-year long sampling campaign. A total of 67 VOCs with average annual concentration of 2903.01 µg/m3 were detected. Ethanol was the dominant species of detected VOCs, accounting for 76.4-82.3% of the total volatile organic compounds (TVOCs) concentration. VOCs emission showed seasonal variation as the highest concentration was detected in summer and lowest appeared in winter. Furthermore, 50 VOCs identified were non-carcinogenic chemicals and 21 of them were carcinogenic chemicals. Risk assessment showed that the average total non-carcinogenic risk value (HIT) was 4.95, which far exceeded the threshold value of 1; and the average total carcinogenic risk value (RiskT) was 8.45 × 10-5, close to the limit of 1 × 10-4. That means both the non-carcinogenic and carcinogenic risks of long-term exposure to these VOCs could not be ignored. Some of the oxygenated compounds (Acrolein, Ethyl acetate, etc.), halocarbons (1,1,2-Trichloroethane, 1,2-Dichloropropane, etc.) and aromatic compounds (Naphthalene, m + p-Xylene, etc.) consisted the main contributors to non-carcinogenic risks. Meanwhile, carcinogenic risks were mainly caused by halocarbons (cis-1,2-Dichloroethylene, FREON11, etc.) and aromatic compounds (Benzene, Ethylbenzene, etc.). In addition, statistical analysis revealed that the HIT values were related to the concentrations of risk aromatic compounds, halocarbons and hydrocarbons; RiskT values were only related to the concentrations of risk aromatic compounds and halocarbons. The research results provide an important theoretical basis for occupational risk management and VOCs emission prevention in landfills.


Assuntos
Hidrocarbonetos Halogenados , Saúde Ocupacional , Compostos Orgânicos Voláteis , Resíduos Sólidos , Acroleína
12.
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
13.
J Hazard Mater ; 441: 129813, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36063714

RESUMO

Disinfection in water treatments induces microplastics (MPs) to produce various derivative products, among which the volatile organic compounds (VOCs) are still poorly understood. Ultraviolet (UV), chlorine and UV/chlorine disinfections were used to treat polypropylene (PP), polystyrene (PS) and polyvinylchloride (PVC) in this study. Modifications were observed on the MP surfaces, including melting, cracks, folds, and even forming oxygen-containing structures, resulting in the release of a diversity of VOCs. The polymer types of MPs influenced the VOCs characteristics. PP released alkanes, alkenes and aldehydes, while PVC released alkanes, alkenes and halogenated hydrocarbons. VOCs from PS were dominated by unique aromatic alkanes, alkenes and aldehydes. These derived VOCs are generated during different disinfections with distinct mechanisms. UV-C at 254 nm induced direct scission and radical oxidation on MPs. The derived VOCs were mainly bond-breaking fragments. Chlorination relied on HOCl/OCl- electrophilic reactions, resulting fewer VOCs since C-C skeleton MPs have strong resistance to electrophilic reactions. UV/chlorination promotes the generation of chlorine radicals and hydroxyl radicals, thereby causing oxidative damage. Various oxidized VOCs, such as benzaldehyde and acetophenone, were formed. The disinfection reactions can produce various VOCs from MPs, posing potential risks to the ecological environment and human beings.


Assuntos
Hidrocarbonetos Halogenados , Compostos Orgânicos Voláteis , Poluentes Químicos da Água , Purificação da Água , Acetofenonas , Alcanos , Benzaldeídos , Cloro/química , Desinfecção/métodos , Halogenação , Humanos , Microplásticos , Oxigênio , Plásticos , Polipropilenos , Poliestirenos , Cloreto de Polivinila , Raios Ultravioleta , Poluentes Químicos da Água/química , Purificação da Água/métodos
14.
Front Biosci (Landmark Ed) ; 27(11): 314, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36472117

RESUMO

Aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, mercury, nickel, thallium, titanium, zinc, carbon tetrachloride, phthalates, glyphosate, alcohol, drugs, and herbs are under discussion having the potential to injure the human liver, but allocation of the injury to the hepatotoxicant as exact cause is difficult for physicians and requires basic clinical knowledge of toxicology details. Liver injury occurs at a variable extent depending on the dose, mostly reproducible in animal models that allow studies on molecular steps leading to the hepatocellular injury. These exogenous hepatotoxins may cause an overproduction of reactive oxidative species (ROS), which are generated during microsomal or mitochondrial oxidative stress from incomplete oxygen split and trigger the injury if protective antioxidant capacities are reduced. Primary subcelluar target organelles involved are liver mitochondria through lipid peroxidation of membrane structures and the action of free radicals such as singlet radical 1O2, superoxide radical HO•2, hydrogen peroxide H2O2, hydroxyl radical HO•, alkoxyl radical RO•, and peroxyl radical ROO•. They attempt covalent binding to macromolecular structural proteins. As opposed to inorganic chemicals, liver injury due to chemicals with an organic structure proceedes via the hepatic microsomal cytochrome P450 with its different isoforms. In sum, many exogenous chemicals may have the potential of liver injury triggerd by overproduced ROS leading primarily to impairment of mitochondial functions in the course of structural mitochondial membrane dearrangement. As clinical data were often incomplete, future clinical prototols should focus on meeting liver injury criteria, exclusion of alternative causes, a robust causality evaluation management, and obtaining liver histology if clinically indicated and of benefit for the patient.


Assuntos
Hidrocarbonetos Halogenados , Metais Pesados , Animais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/metabolismo , Hidrocarbonetos Halogenados/metabolismo , Metais Pesados/toxicidade , Etanol/metabolismo , Fígado/metabolismo , Estresse Oxidativo
15.
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
16.
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
17.
Int J Mol Sci ; 23(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35328534

RESUMO

In the current study, unexplored type IV halogen⋯halogen interaction was thoroughly elucidated, for the first time, and compared to the well-established types I−III interactions by means of the second-order Møller−Plesset (MP2) method. For this aim, the halobenzene⋯halobenzene homodimers (where halogen = Cl, Br, and I) were designed into four different types, parodying the considered interactions. From the energetic perspective, the preference of scouted homodimers was ascribed to type II interactions (i.e., highest binding energy), whereas the lowest binding energies were discerned in type III interactions. Generally, binding energies of the studied interactions were observed to decline with the decrease in the σ-hole size in the order, C6H5I⋯IC6H5 > C6H5Br⋯BrC6H5 > C6H5Cl⋯ClC6H5 homodimers and the reverse was noticed in the case of type IV interactions. Such peculiar observations were relevant to the ample contributions of negative-belt⋯negative-belt interactions within the C6H5Cl⋯ClC6H5 homodimer. Further, type IV torsional trans → cis interconversion of C6H5X⋯XC6H5 homodimers was investigated to quantify the π⋯π contributions into the total binding energies. Evidently, the energetic features illustrated the amelioration of the considered homodimers (i.e., more negative binding energy) along the prolonged scope of torsional trans → cis interconversion. In turn, these findings outlined the efficiency of the cis configuration over the trans analog. Generally, symmetry-adapted perturbation theory-based energy decomposition analysis (SAPT-EDA) demonstrated the predominance of all the scouted homodimers by the dispersion forces. The obtained results would be beneficial for the omnipresent studies relevant to the applications of halogen bonds in the fields of materials science and crystal engineering.


Assuntos
Halogênios , Hidrocarbonetos Halogenados , Benzeno , Halogênios/química , Modelos Teóricos
18.
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
19.
Int J Mol Sci ; 23(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35163284

RESUMO

Heart disease requires a surgical approach sometimes. Cardiac-surgery patients develop heart failure associated with ischemia induced during extracorporeal circulation. This complication could be decreased with anesthetic drugs. The cardioprotective effects of halogenated agents are based on pre- and postconditioning (sevoflurane, desflurane, or isoflurane) compared to intravenous hypnotics (propofol). We tried to put light on the shadows walking through the line of the halogenated anesthetic drugs' effects in several enzymatic routes and oxidative stress, waiting for the final results of the ACDHUVV-16 clinical trial regarding the genetic modulation of this kind of drugs.


Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Insuficiência Cardíaca/etiologia , Hidrocarbonetos Halogenados/farmacologia , Anestésicos Inalatórios/farmacologia , Procedimentos Cirúrgicos Cardíacos/métodos , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/cirurgia , Cardiotônicos/farmacologia , Insuficiência Cardíaca/mortalidade , Humanos , Isoflurano/farmacologia , Miocárdio/patologia , Estresse Oxidativo/fisiologia , Propofol/farmacologia , Sevoflurano/farmacologia
20.
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
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