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1.
Environ Monit Assess ; 192(11): 680, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025180

RESUMO

In this study, the activities of 40K, 210Pb, 232Th, 234U, 235U, and 238U in size-segregated particulate matter (PM) were measured in the Singrauli Coalfield, India. Different isotopic compositions were found relative to natural uranium ratios. The radioactivity concentration ratios in different PM sizes [PM2.5, PM10, and suspended particulate matter (SPM)] suggested that anthropogenic sources affected the uranium isotopic compositions in the area. A different isotopic composition from the natural uranium composition was found. The correlation coefficients between the measured isotopes (40K, 210Pb, 232Th, 234U, 235U, and 238U) and meteorological factors were calculated. PM emissions were affected by the meteorological conditions, which in turn, influenced the U and Th concentrations in PM. The 232Th/238U activity ratio in particulate matter was between 0.20 and 1.54 with an average value of 0.9 ± 0.5, 0.2 to 1.1 (0.8 ± 0.7), and 0.2 to 1.2 with an average value of 0.8 ± 0.8 in PM2.5, PM10, and SPM, respectively. These range were quite different from the average crustal ratio of 3.5, indicating that the 238U concentrations were elevated in this region relative to Th. However, compared with Th, the dose contribution of U to the public was negligible. The average effective dose in public owing to inhalation of natural radioactive 40K, 210Pb, 232Th, and 234U, 235U, and 238U in the atmosphere was between 0.03 and 327 nSv year-1. These doses associated with the inhalation of particulate matter were lower than world airborne reference value as reported by UNSCEAR (2000a). Graphical abstract.


Assuntos
Neoplasias , Material Particulado , Monitoramento Ambiental , Humanos , Índia , Material Particulado/análise , Radioisótopos
2.
Environ Monit Assess ; 192(11): 676, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025262

RESUMO

Long-term aerosol optical thickness (AOT) composited data (2002-2017) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra and Aqua spacecraft was used to evaluate the temporal and spatial variability of aerosol in Xiamen city by using wavelet analysis, and the relationship between the surface mass concentrations of particulate matter with aerodynamic diameters less than 2.5 µm (PM2.5) and the AOT was analyzed by using linear regression. The results showed that AOT increased gradually from 2002 to 2011, and then decreased. AOT displayed a significant 9-month periodicity in AOT was inferred wavelet analysis. AOT also showed significant annual variability in response to changes in weather and aerosol pollution. We observed highest AOT values in April, with a monthly mean of 1.00 ± 0.18. Lowest values were observed in December, with a mean AOT of 0.52 ± 0.11. Multi-year monthly AOT fluctuations were lowest in January with a low variation coefficient (0.14), and the largest fluctuations appeared in July with a high variation coefficient (0.29). Higher AOT values (~ 1.1) were predominantly located in the southern urban areas of Xiamen and lower AOT values (~ 0.3) were mainly located in northern rural regions. The aerosol pollution was serious in April with the smallest spatial variation coefficient of 0.25, and the highest spatial variation coefficient appeared in July. Highest intraannual variability predominantly occurred in the high-value areas in the center of Xiamen. AOT values remained high in Xiamen Island throughout the year with a multi-year mean of 0.87. There was a moderate correlation between ground-based PM2.5 and MODIS AOT. Therefore, we confirm the suitability of MODIS AOT to accurately estimate PM2.5 concentration and evaluate the temporal and spatial characteristics of air quality in Xiamen.


Assuntos
Monitoramento Ambiental , Material Particulado , Aerossóis/análise , China , Cidades , Material Particulado/análise
3.
Environ Monit Assess ; 192(10): 667, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33006063

RESUMO

Dental prosthesis laboratories (DPLs) are among the workplaces where predominantly manual production takes place. In such working environments, during the manual manufacturing process, which involves fine smoothing and polishing of dental prostheses, fine particulate matter is released into the ambient air. In this study, the particulate matter (PM) concentrations and elemental content of the fine particles in the working ambient air were identified in six DPLs in Kocaeli, Turkey. PM2.5 mass concentrations, measured in all the DPLs, ranged between 80.8 and 1645 µg/m3 (mean 414 ± 406). As a result of the analyses performed with an ICP-MS device (Perkin Elmer Elan®DRC-e), trace elements of Be, Cd, Hg, and, notably, Co, Cr, Mo, and Ni were found. The researchers calculated the excess lifetime cancer risks and total hazard indexes. The average total cancer risk for all the DPLs was 8 × 10-3, which is higher than the acceptable limit of 1.0 × 10-6, and the total hazard index was 187, which is greater than the acceptable limit of 1.0. Considering these high-level risks, the study concluded that there is a need for new production methods, and strict application of occupational health and safety measures, to reduce the fine particle exposure of the workers in the laboratories. In addition, there are prescribed limit values for particulate matter only for respirable particles in working environments. The establishment of limit values, especially for PM2.5 concentrations, is important for the protection of the health of the employees.


Assuntos
Prótese Dentária , Exposição Ocupacional , Monitoramento Ambiental , Humanos , Material Particulado/análise , Turquia
4.
Artigo em Inglês | MEDLINE | ID: mdl-33008116

RESUMO

During the first outbreak of the SARS-CoV-2 pandemic the population, focusing primarily on the risk of infection, was generally inattentive to the quality of indoor air. Spain, and the city of Madrid in particular, were among the world's coronavirus hotspots. The country's entire population was subject to a 24/7 lockdown for 45 days. This paper describes a comparative longitudinal survey of air quality in four types of housing in the city of Madrid before and during lockdown. The paper analysed indoor temperatures and variations in CO2, 2.5 µm particulate matter (PM2.5) and total volatile organic compound (TVOC) concentrations before and during lockdown. The mean daily outdoor PM2.5 concentration declined from 11.04 µg/m3 before to 7.10 µg/m3 during lockdown. Before lockdown the NO2 concentration values scored as 'very good' 46% of the time, compared to 90.9% during that period. Although the city's outdoor air quality improved, during lockdown the population's exposure to indoor pollutants was generally more acute and prolonged. Due primarily to concern over domestic energy savings, the lack of suitable ventilation and more intensive use of cleaning products and disinfectants during the covid-19 crisis, indoor pollutant levels were typically higher than compatible with healthy environments. Mean daily PM2.5 concentration rose by approximately 12% and mean TVOC concentration by 37% to 559%. The paper also puts forward a series of recommendations to improve indoor domestic environments in future pandemics and spells out urgent action to be taken around indoor air quality (IAQ) in the event of total or partial quarantining to protect residents from respiratory ailments and concomitantly enhanced susceptibility to SARS-CoV-2, as identified by international medical research.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus , Dióxido de Carbono , Cidades , Habitação/classificação , Humanos , Óxido Nítrico , Material Particulado , Espanha , Compostos Orgânicos Voláteis
5.
Sci Total Environ ; 741: 140515, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887014

RESUMO

An ecologic analysis was conducted to explore the correlation between air pollution, and COVID-19 cases and fatality rates in London. The analysis demonstrated a strong correlation (R2 > 0.7) between increment in air pollution and an increase in the risk of COVID-19 transmission within London boroughs. Particularly, strong correlations (R2 > 0.72) between the risk of COVID-19 fatality and nitrogen dioxide and particulate matter pollution concentrations were found. Although this study assumed the same level of air pollution across a particular London borough, it demonstrates the possibility to employ air pollution as an indicator to rapidly identify the city's vulnerable regions. Such an approach can inform the decisions to suspend or reduce the operation of different public transport modes within a city. The methodology and learnings from the study can thus aid in public transport's response to COVID-19 outbreak by adopting different levels of human-mobility reduction strategies based on the vulnerability of a given region.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus , Cidades , Humanos , Londres , Dióxido de Nitrogênio/análise , Material Particulado/análise
6.
Sci Total Environ ; 741: 140465, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887012

RESUMO

BACKGROUND: Long-term exposure to air pollution is linked with increased risk of adverse health outcomes, but the evidence for the association between nitrogen dioxide (NO2) and mortality is weak because of the inadequate adjustment of potential confounders and limited spatial resolution of the exposure assessment. Moreover, there are concerns about the independent effects of NO2. Therefore, we examined the association between NO2 long-term exposure and all-cause and cause-specific mortality. METHODS: We included participants who were enrolled in health checkups in Okayama City, Japan, in 2006 or 2007 and were followed until 2016. We used a land-use regression model to estimate the average NO2 concentrations from 2006 to 2007 and allocated them to the participants. We estimated hazard ratios (HRs) for a 10-µg/m3 increase in NO2 levels for all-cause or cause-specific mortality using Cox proportional hazard models. RESULTS: After excluding the participants who were assigned with outlier exposures, a total of 73,970 participants were included in the analyses. NO2 exposure was associated with increased risk of mortality and the HRs and their confidence intervals were 1.06 (95% CI: 1.02, 1.11) for all-cause, 1.02 (0.96, 1.09) for cardiopulmonary, and 1.36 (1.14, 1.63) for lung cancer mortality. However, the elevated risks became equivocal after the adjustment for fine particulate matter except lung cancer. CONCLUSION: Long-term exposure to NO2 was associated with increased risk of all-cause, cardiopulmonary, and lung cancer mortality. The elevated risk for lung cancer was still observable even after adjustment for fine particulate matter.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar , Causas de Morte , Poluentes Atmosféricos/toxicidade , Exposição Ambiental/análise , Humanos , Japão , Dióxido de Nitrogênio/análise , Material Particulado/análise
7.
Environ Monit Assess ; 192(10): 624, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895739

RESUMO

Particulate matter (PM) concentrations are affected by anthropogenic emissions and sand transport jointly; however, the relative contributions from those two aspects are usually unknown. In our work, statistical analysis and back trajectories model were used to identify the dominant source in such area, by taking Yumen City as an example. We come to the conclusion that local emissions dominate the concentration of airborne pollutants, while sand transport plays a significant role on PM concentration. The conclusions were supported by the following results. (1) PM monthly mean concentrations at the two air quality stations, which are 70 km far away from each other, have the similar levels and variation trend; furthermore, a regression analysis of PM2.5 and PM10 daily concentrations between both stations indicated a significant correlation, suggesting that PM at both locations was influenced by the same emission sources; (2) statistical analysis results revealed that PM concentration has a positive correlation with wind speed, indicating the wind-blown dust and sand contribute mainly on PM concentration; (3) back-trajectory clustering analysis indicates that long-distance transport particulates from dust sources and their pathways had a significant impact on local PM concentrations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluentes Ambientais , China , Cidades , Monitoramento Ambiental , Material Particulado/análise
8.
Environ Monit Assess ; 192(10): 627, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32901375

RESUMO

Numerous health studies have linked the exposure to particulate matter with adverse health effects, while there is an increasing scientific interest in the particle metrics of surface area (SA) and lung-deposited SA (LDSA) concentration. In the present study, two integrated SA estimation methods, both based on widely used instrumentation, were applied at an urban traffic environment in Athens for a 6-month period. The first estimation method used the size distribution by number to estimate SA (average SA1 669.3 ± 229.0 µm2 cm-3), while the second method used a simple inversion scheme that incorporates number and mass concentrations (average SA2 1627.9 ± 562.8 µm2 cm-3). In pairwise comparisons, SA2 levels were found two times greater than the corresponding SA1, but exhibited a strong correlation (r = 0.73). SA1 and SA2 concentrations correlated well with the traffic-related pollutants NOx (r = 0.64 and 0.78) and equivalent black carbon (r = 0.53 and 0.51). The diurnal variation of SA1 concentrations by size range indicated traffic as a major controlling factor. Estimated LDSA (53.9 µm2 cm-3 on average) concentrations were also clearly affected by anthropogenic emissions with more pronounced associations in the 0.01-0.4 µm range (r = 0.66 with NOx and r = 0.65 with equivalent black carbon). Validating estimated LDSA through simultaneous measurements with a reference instrument revealed that the estimation method underestimates LDSA by a factor between 2 and 3, exhibiting, however, a high correlation (r = 0.79). Overall, the performance of estimation methods appear satisfactory and indicate that a trustworthy assessment of the temporal variability of SA and LDSA concentration metrics can be provided in real time, on the basis of relatively lower-cost instrumentation, especially in view of recent advances in particle sensing technologies.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Grécia , Material Particulado/análise , Emissões de Veículos/análise
9.
J Environ Sci (China) ; 97: 1-10, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933723

RESUMO

Variations of levels, possible source and air mass transmission were investigated for 16 USEPA priority-controlled PAHs in PM2.5 during 2018 Chinese Spring Festival (CSF) in Xiangyang City, central China which is the North-South pollutant airmass transport channel of China. Totally 37 samples were collected. Mass concentrations of Σ16PAHs for the Pre-CSF day (Pre-CSFD), during the CSF day (CSFD) and after the CSF day (Af-CSFD) are 33.78 ± 17.68 ng/m3, 22.98 ± 6.49 ng/m3, and 8.99 ± 4.44 ng/m3, respectively. High resolution samples showed that Σ16PAHs are higher in the morning (06:00-11:00) or afternoon (11:30-16:30), than those in the evening (17:00-22:00) and at night (22:30-05:30), whereas the result is reversed during the CSFD. Fireworks burning can obviously increase the mass concentration of PAHs. Air mass trajectory indicated that Xiangyang is a sink area of pollutants for northwest and southeast, and the sources of the northeast and southwest. The air mass only can be transmitted out through northeast and southwest. It is effective for improvement of air quality in Wuhan and Hunan to control fireworks emission in Henan and local areas. Fireworks burning was an important source for PAHs during CSFD, biomass, coal combustion, and traffic emission were the main sources of PAHs for Pre-CSFD and Af-CSFD periods. The health risk on the CSFD was higher than the acceptable levels, especially during the intensive fireworks burning, the risk value far exceed 1.0 × 10-4, controlling burning fireworks is required.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , China , Cidades , Monitoramento Ambiental , Férias e Feriados , Material Particulado/análise , Estações do Ano
10.
J Environ Sci (China) ; 97: 149-161, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933730

RESUMO

Transboundary and domestic aerosol transport during 2018-2019 affecting Bangkok air quality has been investigated. Physicochemical characteristics of size-segregated ambient particles down to nano-particles collected during 2017 non-haze and 2018-2019 haze periods were analyzed. The average PM2.5 concentrations at KU and KMUTNB sites in Bangkok, Thailand during the haze periods were about 4 times higher than in non-haze periods. The highest average organic carbon and elemental carbon concentrations were 4.6 ± 2.1 µg/m3 and 1.0 ± 0.4 µg/m3, respectively, in PM0.5-1.0 range at KU site. The values of OC/EC and char-EC/soot-EC ratios in accumulation mode particles suggested the significant influence of biomass burning, while the nuclei and coarse mode particles were from mixed sources. PAH concentrations during 2018-2019 haze period at KU and KMUTNB were 3.4 ± 0.9 ng/m3 and 1.8 ± 0.2 ng/m3, respectively. The PAH diagnostic ratio of PM2.5 also suggested the main contributions were from biomass combustion. This is supported by the 48-hrs backward trajectory simulation. The higher PM2.5 concentrations during 2018-2019 haze period are also associated with the meteorological conditions that induce thermal inversions and weak winds in the morning and evening. Average values of benzo(a)pyrene toxic equivalency quotient during haze period were about 3-6 times higher than during non-haze period. This should raise a concern of potential human health risk in Bangkok and vicinity exposing to fine and ultrafine particulate matters in addition to regular exposure to traffic emission.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar , Aerossóis/análise , Biomassa , Carbono/análise , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Tailândia
11.
J Environ Sci (China) ; 97: 85-95, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933743

RESUMO

Agriculture-oriented cities in Northeastern China have experienced frequent atmospheric pollution events. Deeper understandings of the pollution characteristics, haze causes and effects of management on local air quality are crucial for conducting integrated management approaches for the sustainable development of agriculture-oriented cities. Taking a typical agriculture-dominant city (i.e., Suihua) in Northeast China, we analyzed in detail the characteristics and causes of atmospheric pollution and evaluated the straw-burning prohibition using multisource data. The results showed a clear temporal pattern of air quality index (AQI) on an annual scale (i.e., 2015-April 2019), with two typical pollution periods occurring in late autumn and early spring. The large areas of concentrated straw burning at local and regional scales accounted for the first period (i.e., October and November), while dust emissions and farming disturbances comprised the second period. The interannual variation in pollution periods among these years was large, showing similar trends from 2015 to 2017 and the postponed late-autumn pollution period in 2018. Our evaluation has shown that the prohibition effect of straw burning significantly improved air quality in 2018, with a reduction of 59% ± 88% in the PM2.5 concentrations in October and November compared to 2015-2017. However, From October to April of the following year, the improvement effect was not significant due to postponement of straw burning to February or March. Our analysis also highlighted the roles of meteorological conditions, Therefore, combined with the promotion of straw utilization, scientifically prescribed burning considering the burning amount and location, meteorological conditions and regional transportation should be implemented.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Agricultura , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano
12.
J Environ Sci (China) ; 97: 96-101, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933744

RESUMO

Emission from burning coals is one of the major sources of the airborne particles in China. We carried out a study on the rare earth elements (REEs) in the inhalable particulate matter (PM10) emitted from burning coals and soil-coal honeycomb briquettes with different volatile contents and ash yields in a combustion-dilution system. Gravimetric analysis indicates that the equivalent mass concentration of the PM10 emitted from burning the coals is higher than that emitted from burning the briquettes. The ICP-MS analysis indicates that the contents of total REEs in the coal-burning PM10 are lower than those in the briquette-burning PM10. In addition, the contents of the light rare earth elements (LREEs) are higher than those of the heavy rare earth elements (HREEs) in the PM10 emitted from burning the coals and briquettes, demonstrating that the REEs in both the coal-burning and briquette-burning PM10 are dominated by LREEs. The higher contents of total REEs and LREEs in the coal-burning PM10 are associated with the higher ash yields and lower volatile contents in the raw coals. A comparative analysis indicates that the La/Sm ratios in the PM10 emitted from burning the coals and briquettes, being lower than 2, are lower than those in the particles from gasoline-powered vehicle emission.


Assuntos
Poluentes Atmosféricos/análise , Carvão Mineral/análise , China , Monitoramento Ambiental , Material Particulado/análise , Solo
13.
Environ Monit Assess ; 192(10): 646, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32939661

RESUMO

We investigated the associations between the daily variations of coarse particulate matter (PM10) and/or sulfur dioxide (SO2) and hospital admissions for asthma and/or chronic obstructive pulmonary disease (COPD) diseases in Kirsehir, Center of Anatolia of Turkey. We analyzed the poison generalized linear model (GLM) to analyze the association between ambient air pollutants such as PM10 and SO2 and asthma and/or COPD admissions. We investigated single-lag days and multi-lag days for the risk increase in asthma, COPD, asthma, and/or COPD hospital admissions PM10, SO2, and PM10 with SO2 per 10 µg/m3. In single-lag day model a 10 µg/m3 increase in the current day (lag 0) concentrations of PM10 and SO2 corresponded to increase of 1.027 (95% CI:1.022-1.033) and 1.069 (95% CI:1.062, 1.077) for asthma. A 10 µg/m3 increase in the current day (lag 0) concentrations of PM10 and SO2 corresponded to increase of 1.029 (95% CI:1.022-1.035) and 1.065 (95% CI:1.056, 1.075) for COPD. A 10 µg/m3 increase in the current day (lag 0) concentrations of PM10 and SO2 corresponded to increase of 1.028 (95% CI:1.024-1.032) and 1.068 (95% CI:1.062, 1.074) for asthma and/or COPD. It was found that some lag structures were related with PM10 and SO2. Significant lags were detected in some lag structures from the previous first day until the previous eighth day (lag 1 to lag 7) in the asthma, COPD, and asthma and/or COPD hospital admissions in the model created with PM10 with SO2 both in the single-lag day model and in the multi-lag day model. Our study that used GLM in time series analysis showed that PM10 and/or SO2 short-term exposure in single-lag day and multi-lag day models was related with increased asthma, COPD, and asthma and/or COPD hospital admissions in the city between 2016 and 2019 until the previous-eighth day.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Asma , Doença Pulmonar Obstrutiva Crônica , Monitoramento Ambiental , Humanos , Dióxido de Nitrogênio/análise , Material Particulado/análise , Dióxido de Enxofre/análise , Turquia
14.
Ecotoxicol Environ Saf ; 203: 111044, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888613

RESUMO

BACKGROUND: Exposure to ambient fine particulate matter (PM2.5) is associated with various adverse health outcomes. Although several mechanisms have been proposed including oxidative stress and inflammatory responses, the exact mechanism is still unknown. Few studies have investigated the mechanism linking PM2.5 and blood pressure (BP). In this study, we measured urinary metabolites and BP -related renin-angiotensin-aldosterone system (RAAS) to investigate the associations between ambient PM2.5 exposure and BP in healthy C57BL/6 mice. METHODS: The C57BL/6 mice were exposed to ambient concentrated PM2.5 or filtered air (FA) for 16 weeks. Systolic BP and diastolic BP were measured by noninvasive BP system. The urine metabolites were quantified using the untargeted metabolomics approach. The expression of RAAS-related proteins angiotensin-converting enzyme (ACE)2, angiotensin (Ang) II, Ang (1-7) and aldosterone (ALD) were measured using Western blot and ELISA kits. RESULTS: The metabolomics analysis demonstrated that PM2.5 exposure induced significant changes of some metabolites in urine, including stress hormones, amino acids, fatty acids, and lipids. Furthermore, there was an elevation of BP, increase of serous Ang II and ALD, along with the decrease of ACE2 and Ang (1-7) in kidney in the PM2.5-exposed mice compared with FA-exposed mice. CONCLUSIONS: The results demonstrated that PM2.5 exposure-induced BP elevation might be associated with RAAS activation. Meanwhile, PM2.5 exposure-induced changes of stress hormone and lipid metabolism might mediate the activation of RAAS. The results suggested that the systemic stress hormone and lipid metabolism was associated with the development of hypertension.


Assuntos
Poluentes Atmosféricos/toxicidade , Angiotensina I/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/induzido quimicamente , Material Particulado/toxicidade , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Acetilglucosaminidase/urina , Angiotensina I/sangue , Animais , Biomarcadores/sangue , Biomarcadores/urina , Hipertensão/urina , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Metaboloma/efeitos dos fármacos , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/sangue , Peptidil Dipeptidase A/sangue , Sistema Renina-Angiotensina/efeitos dos fármacos , beta-Galactosidase/urina
15.
BMJ Open ; 10(9): e039424, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963071

RESUMO

OBJECTIVE: We examined the ability of fabrics which might be used to create home-made face masks to filter out ultrafine (0.02-0.1 µm) particles at the velocity of adult human coughing. METHODS: Twenty commonly available fabrics and materials were evaluated for their ability to reduce air concentrations of ultrafine particles at coughing face velocities. Further assessment was made on the filtration ability of selected fabrics while damp and of fabric combinations which might be used to construct home-made masks. RESULTS: Single fabric layers blocked a range of ultrafine particles. When fabrics were layered, a higher percentage of ultrafine particles were filtered. The average filtration efficiency of single layer fabrics and of layered combination was found to be 35% and 45%, respectively. Non-woven fusible interfacing, when combined with other fabrics, could add up to 11% additional filtration efficiency. However, fabric and fabric combinations were more difficult to breathe through than N95 masks. CONCLUSIONS: The current coronavirus pandemic has left many communities without access to N95 face masks. Our findings suggest that face masks made from layered common fabric can help filter ultrafine particles and provide some protection for the wearer when commercial face masks are unavailable.


Assuntos
Infecções por Coronavirus/transmissão , Tosse , Máscaras/provisão & distribução , Teste de Materiais , Material Particulado , Pneumonia Viral/transmissão , Têxteis , Filtros de Ar , Betacoronavirus , Celulose , Infecções por Coronavirus/prevenção & controle , Fibra de Algodão , Humanos , Nylons , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Poliésteres , Poliuretanos , Dispositivos de Proteção Respiratória/provisão & distribução , Fibra de Lã
16.
Chemosphere ; 258: 127312, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947663

RESUMO

As recognized risk factor to pose a health threat to humans and wildlife globally, atmospheric particulate matter (PM) were collected from a North African coastal city (Bizerte, Tunisia) for one year, and were characterized for their chemical compositions, including mercury (HgPM), as well as organic contaminants (polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs)), organic carbon (OC) and organic nitrogen (ON), determined in a previous study. Then, we applied an in vitro reporter gene assay (DR-CALUX) to detect and quantify the dioxin-like activity of PM-associated organic contaminants. Results showed that average HgPM concentration over the entire sampling period was found to be 13.4 ± 12 pg m-3. Seasonal variation in the HgPM concentration was observed with lower values in spring and summer and higher values in winter and autumn due to the variation of meteorological conditions together with the emission sources. Principal component analysis suggested that fossil fuel combustion and a nearby cement factory were the dominant anthropogenic HgPM sources. Aryl hydrocarbon receptor (AhR)-mediated activities were observed in all organic extracts of atmospheric PM from Bizerte city (388.3-1543.6 fg m-3), and shows significant positive correlations with all PM-associated organic contaminants. A significant proportion of dioxin-like activity of PM was related to PAHs. The dioxin-like activity followed the same trend as PM-associated organic contaminants, with higher dioxin-like activity in the cold season than in the warm season, indicating the advantage and utility of the use of bioassays in risk assessment of complex environmental samples.


Assuntos
Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Agricultura , Poluentes Atmosféricos/análise , Cidades , Clima , Dioxinas/análise , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Receptores de Hidrocarboneto Arílico , Estações do Ano , Tunísia
17.
Chemosphere ; 258: 127310, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947673

RESUMO

We characterized the aerosol composition and sources of particulate matter (PM) in Sanmenxia, a polluted city located in the Fen-Wei Plain region of Central China. The PM2.5 concentration decreased by 18% from 72 µg m-3 in 2014 to 59 µg m-3 in 2019. All chemical species presented pronounced seasonal variations, with their highest concentrations in winter due to enhanced emissions and the frequent stagnant meteorological conditions. Nitrate was the major fraction of PM2.5 during all seasons (35-41%) except summer (25%), while sulfate was a dominant species in summer (29%) compared to other seasons (16-18%) from July 2018 to June 2019. The detailed analysis of a wintertime severe haze episode that lasted for approximately half a month demonstrated that secondary aerosols, including secondary organic aerosol, sulfate, nitrate, and ammonium, contributed 89% to non-refractory PM1 (NR-PM1), indicating the remarkable role of secondary aerosol formation in air pollution in Sanmenxia. Positive matrix factorization analysis further showed considerably enhanced low-volatility oxygenated organic aerosol (OA) and hydrocarbon-like OA during severe haze episodes, while significant contributions in semi-volatile oxygenated OA and coal combustion OA during clean periods. Severe pollution events in the city were generally associated with air masses from the southwest, and we also found that aerosol species, especially secondary aerosol species, showed distinct forenoon increases that were caused by the subsidence of air pollutants aloft. Our results highlight that future air quality improvement would benefit substantially from a more efficient control of gaseous precursors, particularly the NOx emissions from industry and vehicle emissions.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , China , Cidades , Carvão Mineral/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Poluição Ambiental/análise , Hidrocarbonetos/química , Nitratos/análise , Óxidos de Nitrogênio/análise , Material Particulado/análise , Estações do Ano , Emissões de Veículos/análise
18.
Chemosphere ; 258: 127367, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947676

RESUMO

Due to their important roles in salt-producing acid-base reactions, new particle formation (NPF), and as precursors in secondary organic aerosol (SOA) producing reactions, the atmospheric concentrations of particulate volatile amines (dimethylamine (DMA), ethylamine, diethylamine (DEA), propylamine, and butylamine) at Seoul were analyzed and evaluated. To quantify the presence of volatile amines in particulate matter with aerodynamic diameters less than or equal to a nominal 2.5 µm (PM2.5), an efficient and rapid analytical method based on in-matrix ethyl chloroformate (ECF) derivatization followed by headspace solid-phase microextraction (HS-SPME) was developed and validated using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) in the multiple reaction monitoring (MRM) mode. The annual mean concentration of the total 5 target amines was 5.56±2.76 ng/m3 and the seasonal difference was small. The concentrations of particulate amines measured in this study were lower than those observed in Zongludak, Turkey, Nanjing, China, and Jeju, Korea but slightly higher than that reported in Kobe, Japan. The concentrations of the nitrosamines (nitrosodimethylamine (NDMA) and nitrosodiethylamine (NDEA)), and of the nitramines (dimethylnitramine (DMN) and diethylnitramine (DEN)) measured along with those of the target amines were used in a simple linear regression analysis. It indicates the contribution of DMA to the formation of NDMA in all seasons (except the fall) and DEA to the formation of NDEA in the summer, while DMA and DEA did not significantly contribute to the formation of nitramines.


Assuntos
Poluentes Atmosféricos/análise , Aminas/análise , Monitoramento Ambiental , China , Dietilnitrosamina , Dimetilaminas , Dimetilnitrosamina/análise , Etilaminas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nitrosaminas/análise , Material Particulado/análise , República da Coreia , Seul , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem
19.
Chemosphere ; 254: 126822, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957270

RESUMO

Atmosphere contamination management is one of the most important features in pollution risk management. The worldwide rise in tourism increases apprehension about its probable destructive conservation influence on various aspects of global conservation. One of the principal dangers increased by tourism-based modes of travel are nanoparticles (NPs) containing potentially hazardous elements (PHEs) contamination. One example of this is island destination of Lanzarote, in Spain's Canary Islands in which we examined contamination of the local atmosphere, water and soil. Important NPs containing PHEs, (e.g. arsenic, chromium, lead, and mercury), were found in this locale. It is reasonable to assume that this pollution poses an increased environmental danger to the local biome(s). Modes of transport (i.e. by car, airplane, bus) were shown to be an important contributor to this localized contamination as demonstrated by particulate matter (PM) readings collected near the island's airport. If no measures are taken to reduce vehicle and aircraft traffic, the tendency is to increase environmental degradation will continue unabated. As this particular area of Lanzarote is also one of wine production, increased pollution has the potential for negative impacts on the region's economy.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Nanopartículas/análise , Material Particulado/análise , Emissões de Veículos/análise , Aeronaves , Aeroportos , Atmosfera , Ecossistema , Poluição Ambiental , Geologia , Ilhas , Solo , Espanha
20.
Artigo em Inglês | MEDLINE | ID: mdl-32867037

RESUMO

Seoul, the most populous city in South Korea, has been practicing social distancing to slow down the spread of coronavirus disease 2019 (COVID-19). Fine particulate matter (PM2.5) and other air pollutants measured in Seoul over the two 30 day periods before and after the start of social distancing are analyzed to assess the change in air quality during the period of social distancing. The 30 day mean PM2.5 concentration decreased by 10.4% in 2020, which is contrasted with an average increase of 23.7% over the corresponding periods in the previous 5 years. The PM2.5 concentration decrease was city-wide and more prominent during daytime than at nighttime. The concentrations of carbon monoxide (CO) and nitrogen dioxide (NO2) decreased by 16.9% and 16.4%, respectively. These results show that social distancing, a weaker forcing toward reduced human activity than a strict lockdown, can help lower pollutant emissions. At the same time, synoptic conditions and the decrease in aerosol optical depth over the regions to the west of Seoul support that the change in Seoul's air quality during the COVID-19 social distancing can be interpreted as having been affected by reductions in the long-range transport of air pollutants as well as local emission reductions.


Assuntos
Poluição do Ar/análise , Infecções por Coronavirus/epidemiologia , Monitoramento Ambiental , Pneumonia Viral/epidemiologia , Poluentes Atmosféricos/análise , Betacoronavirus , Humanos , Pandemias , Material Particulado/análise , Seul
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