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1.
Sci Total Environ ; 690: 1355-1368, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470497

RESUMO

Native and transplanted lichens were analyzed as bioaccumulators of airborne particulate matter (PM) in an eastern district of Rome, Italy, where frequent fraudulent fires are set to recover metals, mostly copper, from waste electrical and electronic equipment (WEEE). The presence of native lichens was scarce, due to the drought of spring-summer 2017, thus, sampling was extended to a neighboring area for toughening the dataset to a similar context. The magnetic analyses revealed intense properties connected to the anthropic complexity of the zone, where industrial, traffic and arson-related dusts are emitted and bio-accumulated. Magnetic and chemical analyses were compared, leading to significant linear correlations between the concentration dependent magnetic parameters (susceptibility, saturation magnetization and saturation remanence) and the concentration of heavy metals, among which copper, chrome, lead and zinc. Moreover, selected magnetic particles were chemically and morphologically characterized by Scanning Electron Microscope and Energy Dispersion System microanalyses. Magnetic particles resulted incorporated into the lichens' tissues and their composition, morphology and grain size strongly supported their anthropogenic, mostly combustion-related, origin. Even if, given the complexity of the area, it was not feasible to fully discriminate the multiple anthropogenic sources, magnetic biomonitoring of lichens, especially when combined with microtextural and compositional analyses, confirmed to be an excellent methodology for a rapid characterization of environmental pollution.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Líquens/química , Material Particulado/análise , Itália , Magnetismo , Roma
3.
N Engl J Med ; 381(8): 705-715, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31433918

RESUMO

BACKGROUND: The systematic evaluation of the results of time-series studies of air pollution is challenged by differences in model specification and publication bias. METHODS: We evaluated the associations of inhalable particulate matter (PM) with an aerodynamic diameter of 10 µm or less (PM10) and fine PM with an aerodynamic diameter of 2.5 µm or less (PM2.5) with daily all-cause, cardiovascular, and respiratory mortality across multiple countries or regions. Daily data on mortality and air pollution were collected from 652 cities in 24 countries or regions. We used overdispersed generalized additive models with random-effects meta-analysis to investigate the associations. Two-pollutant models were fitted to test the robustness of the associations. Concentration-response curves from each city were pooled to allow global estimates to be derived. RESULTS: On average, an increase of 10 µg per cubic meter in the 2-day moving average of PM10 concentration, which represents the average over the current and previous day, was associated with increases of 0.44% (95% confidence interval [CI], 0.39 to 0.50) in daily all-cause mortality, 0.36% (95% CI, 0.30 to 0.43) in daily cardiovascular mortality, and 0.47% (95% CI, 0.35 to 0.58) in daily respiratory mortality. The corresponding increases in daily mortality for the same change in PM2.5 concentration were 0.68% (95% CI, 0.59 to 0.77), 0.55% (95% CI, 0.45 to 0.66), and 0.74% (95% CI, 0.53 to 0.95). These associations remained significant after adjustment for gaseous pollutants. Associations were stronger in locations with lower annual mean PM concentrations and higher annual mean temperatures. The pooled concentration-response curves showed a consistent increase in daily mortality with increasing PM concentration, with steeper slopes at lower PM concentrations. CONCLUSIONS: Our data show independent associations between short-term exposure to PM10 and PM2.5 and daily all-cause, cardiovascular, and respiratory mortality in more than 600 cities across the globe. These data reinforce the evidence of a link between mortality and PM concentration established in regional and local studies. (Funded by the National Natural Science Foundation of China and others.).


Assuntos
Poluição do Ar/efeitos adversos , Exposição Ambiental/análise , Mortalidade , Material Particulado/efeitos adversos , Poluição do Ar/análise , Doenças Cardiovasculares/mortalidade , Causas de Morte , Exposição Ambiental/efeitos adversos , Exposição Ambiental/legislação & jurisprudência , Saúde Global , Humanos , Tamanho da Partícula , Material Particulado/análise , Doenças Respiratórias/mortalidade , Risco
4.
JAMA ; 322(6): 546-556, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408135

RESUMO

Importance: While air pollutants at historical levels have been associated with cardiovascular and respiratory diseases, it is not known whether exposure to contemporary air pollutant concentrations is associated with progression of emphysema. Objective: To assess the longitudinal association of ambient ozone (O3), fine particulate matter (PM2.5), oxides of nitrogen (NOx), and black carbon exposure with change in percent emphysema assessed via computed tomographic (CT) imaging and lung function. Design, Setting, and Participants: This cohort study included participants from the Multi-Ethnic Study of Atherosclerosis (MESA) Air and Lung Studies conducted in 6 metropolitan regions of the United States, which included 6814 adults aged 45 to 84 years recruited between July 2000 and August 2002, and an additional 257 participants recruited from February 2005 to May 2007, with follow-up through November 2018. Exposures: Residence-specific air pollutant concentrations (O3, PM2.5, NOx, and black carbon) were estimated by validated spatiotemporal models incorporating cohort-specific monitoring, determined from 1999 through the end of follow-up. Main Outcomes and Measures: Percent emphysema, defined as the percent of lung pixels less than -950 Hounsfield units, was assessed up to 5 times per participant via cardiac CT scan (2000-2007) and equivalent regions on lung CT scans (2010-2018). Spirometry was performed up to 3 times per participant (2004-2018). Results: Among 7071 study participants (mean [range] age at recruitment, 60 [45-84] years; 3330 [47.1%] were men), 5780 were assigned outdoor residential air pollution concentrations in the year of their baseline examination and during the follow-up period and had at least 1 follow-up CT scan, and 2772 had at least 1 follow-up spirometric assessment, over a median of 10 years. Median percent emphysema was 3% at baseline and increased a mean of 0.58 percentage points per 10 years. Mean ambient concentrations of PM2.5 and NOx, but not O3, decreased substantially during follow-up. Ambient concentrations of O3, PM2.5, NOx, and black carbon at study baseline were significantly associated with greater increases in percent emphysema per 10 years (O3: 0.13 per 3 parts per billion [95% CI, 0.03-0.24]; PM2.5: 0.11 per 2 µg/m3 [95% CI, 0.03-0.19]; NOx: 0.06 per 10 parts per billion [95% CI, 0.01-0.12]; black carbon: 0.10 per 0.2 µg/m3 [95% CI, 0.01-0.18]). Ambient O3 and NOx concentrations, but not PM2.5 concentrations, during follow-up were also significantly associated with greater increases in percent emphysema. Ambient O3 concentrations, but not other pollutants, at baseline and during follow-up were significantly associated with a greater decline in forced expiratory volume in 1 second per 10 years (baseline: 13.41 mL per 3 parts per billion [95% CI, 0.7-26.1]; follow-up: 18.15 mL per 3 parts per billion [95% CI, 1.59-34.71]). Conclusions and Relevance: In this cohort study conducted between 2000 and 2018 in 6 US metropolitan regions, long-term exposure to ambient air pollutants was significantly associated with increasing emphysema assessed quantitatively using CT imaging and lung function.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Pulmão/fisiologia , Enfisema Pulmonar , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono/efeitos adversos , Carbono/análise , Estudos de Coortes , Progressão da Doença , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Óxidos de Nitrogênio/efeitos adversos , Óxidos de Nitrogênio/análise , Ozônio/efeitos adversos , Ozônio/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Enfisema Pulmonar/epidemiologia , Enfisema Pulmonar/fisiopatologia , Testes de Função Respiratória , Tomografia Computadorizada por Raios X , Estados Unidos/epidemiologia
5.
Toxicol Lett ; 315: 14-22, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31400404

RESUMO

In vitro testing can facilitate the rapid assessment of next generation nicotine delivery products (NGPs) with comparisons to combustible tobacco products. In vitro assays for cytotoxicity and oxidative stress were employed at BAT (UK) and JT (Japan) to test total particulate matter (TPM) of a scientific reference cigarette and aerosol collected mass (ACM) of a commercially available E-cigarette and two tobacco heating products (THP). 3R4F TPMs were generated using the Health Canada intense (HCI) regimen, a modified regime (mHCI) for the THP ACMs and the CORESTA recommended method no. 81 for the E-cigarette ACM. Human lung cells were exposed to the test product TPM/ACMs at concentrations between 0-200 µg/ml followed by the employment of commercially available assays for endpoint analysis that included reactive oxygen species (ROS) generation, the glutathione ratio (GSH:GSSG), activation of the antioxidant response elements (ARE) and cellular viability. TPM/ACM nicotine concentrations were quantified using a UPLC-PDA technique. At both laboratories the 3R4F TPM induced significant and dose-dependent responses in all in vitro assays, whereas no significant responses could be measured for the NGP ACMs. In conclusion, both laboratories obtained comparable results across all endpoints therefore demonstrating the utility of the in vitro techniques combined with standardised test products to support the assessment of NGPs.


Assuntos
Aerossóis/análise , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nicotina/análise , Material Particulado/análise , Produtos do Tabaco/análise , Sistemas Eletrônicos de Liberação de Nicotina , Humanos , Japão , Reino Unido
6.
Environ Monit Assess ; 191(8): 528, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367959

RESUMO

The distribution and bioavailability of arsenic (As) in indoor/outdoor total suspended particulates (TSP), inhalable particulate matters (PM10), and fine particulate matters (PM2.5) in Baoding, China were investigated. The average I/O ratios for TSP, PM10, and PM2.5 were 0.52, 0.66, and 0.96, respectively. There was no significant correlation between indoor/outdoor TSP, PM10, and PM2.5. The indoor/outdoor concentrations of As surpassed the limited value of As. I/O ratios of arsenic in TSP, PM10, and PM2.5 were 0.52, 0.58, and 0.55, respectively. The contents of arsenic in different fractions were mainly affected by the total concentrations of arsenic in particulate matters (PM) rather than the particle sizes for TSP and PM10. Arsenic was mainly in non-specifically sorbed fraction (F1) in both indoor and outdoor PM2.5. The evaluated carcinogenic risk (CR) was within the safe level. The bioavailability of As increased with particle size decreasing for both indoor and outdoor PM. The potential bioavailability of As in outdoor particles was higher than that of indoor particles with the same size, especially PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Arsênico/análise , Material Particulado/química , Poluentes Atmosféricos/química , Poluição do Ar em Ambientes Fechados/análise , Arsênico/química , China , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/análise
7.
Environ Sci Process Impacts ; 21(8): 1403-1415, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31389929

RESUMO

Fine particulate air pollution (PM2.5) is a health hazard with numerous indoor and outdoor sources. Versatile monitors are needed to characterize PM2.5 sources, concentrations, and exposures in a range of locations and applications. Whereas low-cost light-scattering PM sensors provide real-time measurements with limited accuracy, gravimetric samples provide more accurate, albeit time-integrated, measurements. When used together, low-cost sensor data can be corrected to gravimetric samples. Here we describe the development of a portable PM2.5 monitor that features a low-cost sensor in line with an active filter sampler. Laboratory tests were conducted to determine (1) the accuracy and precision of PM2.5 concentrations derived from the filter sample and (2) correction factors for the low-cost sensor response to ammonium sulfate, Arizona road dust, urban particulate matter, and match smoke. Filter samples collected at 0.25 and 1.0 L min-1 had mean biases of -10% and -4%, relative to a tapered element oscillating microbalance, and a relative standard deviation (RSD) that ranged from 1% to 17%. The low-cost sensor correction factor varied with the test aerosol, sample flow rate, and between individual monitors. Gravimetric correction reduced the bias and RSD of ∼1 hour average concentrations measured by low-cost sensors in three collocated monitors. A week-long field experiment was also conducted to investigate how the monitor could be used to learn about sources of residential air pollution. Field data were used to identify: (1) pollution events resulting from cooking and use of a wood furnace and (2) variations in the number of air changes per hour inside the residence.


Assuntos
Filtros de Ar , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Habitação/normas , Material Particulado/análise , Análise Custo-Benefício , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Humanos
8.
J Environ Radioact ; 208-209: 106000, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31279226

RESUMO

To retrieve the diffusion trajectory of the 131I dispersed in the environment by the nuclear power plant accident in Fukushima in 2011, airborne particulate matter (APM) samples collected in the Tokyo metropolitan area were analyzed for their 129I contents by means of accelerator mass spectrometry. In evaluating blank levels of chemicals and filters used for collecting APM, we established the analytical procedure for determining the 129I activity of as low as 10-8 Bq for a small piece of filter samples (about 0.1 cm2). Coupled with 131I data determined just after the accident, activity ratios of 129I/131I were obtained with a mean value of 2.29 × 10-8 (±28% of a standard deviation). This value is systematically smaller than a mean value of soil samples by 16-24% and the inventory data by 27%, suggesting that 129I was partly lost from APM. As 129I can be a proxy of 131I for APM, it is possible to trace how 131I in the particulate phase spread in eastern Japan and, furthermore, evaluate the internal radiation exposure due to 131I by inhalation of 131I-containing airborne particulates.


Assuntos
Poluentes Radioativos do Ar/análise , Radioisótopos do Iodo/análise , Material Particulado/análise , Acidente Nuclear de Fukushima , Monitoramento de Radiação
9.
Sci Total Environ ; 691: 868-873, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326810

RESUMO

BACKGROUND: The health effects of particulate matter (PM) air pollution on glucose metabolism have been rarely examined in children and adolescents. OBJECTIVE: We aimed to investigate the associations between long-term PM exposure and blood glucose and prevalence of impaired fasting glucose in a large population of Chinese children and adolescents. METHODS: In 2013, a total of 11,814 children and adolescents aged 7 to 18 years were recruited from seven provinces/municipalities in China. Fasting blood sample was taken for the measurement of blood glucose. Satellite-based spatial-temporal models were used to estimate exposure to ambient submicrometer particles (PM1), fine particles (PM2.5) and thoracic particles (PM10). Cross-sectional analyses were performed using mixed-effects multivariable linear and logistic regression models. RESULTS: After adjustment for a range of covariates, every 10 µg/m3 increment in PM1, PM2.5 and PM10 concentrations was associated with 0.160 [95% confidence interval (CI): 0.039, 0.280], 0.150 (95% CI: 0.044, 0.256) and 0.079 (95% CI: -0.009, 0.167) mmol/L higher blood glucose levels, respectively. PM exposure was also associated with higher prevalence of impaired fasting glucose, but the associations did not reach statistical significance [odds ratio per 10 µg/m3 increment in PM1, PM2.5 and PM10: 1.30 (95% CI: 0.86,1.96), 1.20 (95% CI: 0.85,1.69) and 1.08 (95% CI: 0.83,1.41)]. CONCLUSIONS: We found that long-term exposure to PM air pollution was associated with increased levels of blood glucose in children and adolescents. The associations were more evident for PM1 and PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Glicemia/metabolismo , Exposição Ambiental/estatística & dados numéricos , Material Particulado/análise , Adolescente , Criança , China , Feminino , Humanos , Masculino
10.
J Environ Sci (China) ; 84: 122-132, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284903

RESUMO

A severe haze episode occurred in winter in the North China Plain (NCP), and the phenomenon of an explosive growth and sharp decline in PM2.5 (particulate matter with an aerodynamic diameter equal to or less than 2.5 µm) concentration was observed. To study the systematic causes for this phenomenon, comprehensive observations were conducted in Beijing from November 26 to December 2, 2015; during this period, meteorological parameters, LIDAR data, and the chemical compositions of aerosols were determined. The haze episode was characterized by rapidly varying PM2.5 concentration, and the highest PM2.5 concentration reached 667 µg/m3. During the haze episode, the NCP was dominated by a weak high-pressure system and continuously low PBL (planetary boundary layer) heights, which are unfavorable conditions for the diffusion of pollutants. The large increases in the concentrations of SNA (SO42-, NO3- and NH4+) during the haze implied that the formation of SNA was the largest contribution. Water vapor also played a vital role in the formation of haze by promoting the chemical transformation of secondary pollutants, which led to higher PM2.5 concentrations. The spatial distributions of PM2.5 in Beijing at different times and the backward trajectories of the air masses also indicated that pollutants from surrounding provinces in particular, contributed to the higher PM2.5 concentration.


Assuntos
Material Particulado/análise , Tempo (Meteorologia) , China , Cidades
11.
J Environ Sci (China) ; 84: 166-173, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284908

RESUMO

The primary purpose of this study was to investigate the effect of a catalyzed continuously regenerating trap (CCRT) system composed of a diesel oxidation catalyst (DOC) and a catalyzed diesel particulate filter (CDPF) on the main gaseous and particulate emissions from an urban diesel bus, as well as the durability performance of the CCRT system. Experiments were conducted based on a heavy chassis dynamometer, and a laboratory activity test as well as X-ray photoelectron spectroscopy (XPS) test were applied to evaluate the changes of the aged CCRT catalyst. Results showed that the CCRT could reduce the CO by 71.5% and the total hydrocarbons (THC) by 88.9%, and meanwhile promote the oxidation of NO. However, the conversion rates for CO and THC dropped to 25.1% and 55.1%, respectively, after the CCRT was used for one year (~60,000 km), and the NO oxidation was also weakened. For particulate emissions, the CCRT could reduce 97.4% of the particle mass (PM) and almost 100% of the particle number (PN). The aging of the CCRT resulted in a reduced PM trapping efficiency but had no observable effect on the PN; however, it increased the proportion of nucleation mode particles. The activity test results indicated that the deterioration of the CCRT was directly relevant to the increase in the light-off temperatures of the catalyst for CO, C3H8 and NO2. In addition, the decreased concentrations of the active components Pt2+ and Pt4+ in the catalyst are also important factors in the CCRT deterioration.


Assuntos
Filtração/instrumentação , Emissões de Veículos/prevenção & controle , Monóxido de Carbono/análise , Catálise , Hidrocarbonetos/análise , Óxidos de Nitrogênio/análise , Material Particulado/análise , Emissões de Veículos/análise
12.
BMC Public Health ; 19(1): 903, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286921

RESUMO

BACKGROUND: Growing evidence links household air pollution exposure from biomass-burning cookstoves to cardiometabolic disease risk. Few randomized controlled interventions of cookstoves (biomass or otherwise) have quantitatively characterized changes in exposure and indicators of cardiometabolic health, a growing and understudied burden in low- and middle-income countries (LMICs). Ideally, the solution is to transition households to clean cooking, such as with electric or liquefied petroleum gas stoves; however, those unable to afford or to access these options will continue to burn biomass for the foreseeable future. Wood-burning cookstove designs such as the Justa (incorporating an engineered combustion zone and chimney) have the potential to substantially reduce air pollution exposures. Previous cookstove intervention studies have been limited by stove types that did not substantially reduce exposures and/or by low cookstove adoption and sustained use, and few studies have incorporated community-engaged approaches to enhance the intervention. METHODS/DESIGN: We conducted an individual-level, stepped-wedge randomized controlled trial with the Justa cookstove intervention in rural Honduras. We enrolled 230 female primary cooks who were not pregnant, non-smoking, aged 24-59 years old, and used traditional wood-burning cookstoves at baseline. A community advisory board guided survey development and communication with participants, including recruitment and retention strategies. Over a 3-year study period, participants completed 6 study visits approximately 6 months apart. Half of the women received the Justa after visit 2 and half after visit 4. At each visit, we measured 24-h gravimetric personal and kitchen fine particulate matter (PM2.5) concentrations, qualitative and quantitative cookstove use and adoption metrics, and indicators of cardiometabolic health. The primary health endpoints were blood pressure, C-reactive protein, and glycated hemoglobin. Overall study goals are to explore barriers and enablers of new cookstove adoption and sustained use, compare health endpoints by assigned cookstove type, and explore the exposure-response associations between PM2.5 and indicators of cardiometabolic health. DISCUSSION: This trial, utilizing an economically feasible, community-vetted cookstove and evaluating endpoints relevant for the major causes of morbidity and mortality in LMICs, will provide critical information for household air pollution stakeholders globally. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02658383 , posted January 18, 2016, field work completed May 2018. Official title, "Community-Based Participatory Research: A Tool to Advance Cookstove Interventions." Principal Investigator Maggie L. Clark, Ph.D. Last update posted July 12, 2018.


Assuntos
Poluição do Ar em Ambientes Fechados/prevenção & controle , Doenças Cardiovasculares/prevenção & controle , Culinária/métodos , Exposição Ambiental/prevenção & controle , Utensílios Domésticos , Adulto , Poluição do Ar em Ambientes Fechados/efeitos adversos , Biomassa , Doenças Cardiovasculares/etiologia , Exposição Ambiental/efeitos adversos , Características da Família , Feminino , Honduras , Humanos , Pessoa de Meia-Idade , Material Particulado/análise , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , População Rural , Adulto Jovem
13.
Chemosphere ; 233: 852-861, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340411

RESUMO

A common strategy to improve indoor air quality in households burning coal and biomass is the introduction of advanced combustion solid fuel stoves, which can use existing fuels yet emit fewer pollutants. Chemical composition of PM is affected by numerous combustion parameters, but is often not considered in energy transitions, despite varying toxicity among chemical components. We analyzed PM2.5 emissions from combustion of solid fuels (coal, wood, and straw; whole and pelletized) in a variety of stoves (cookstoves and heating stoves; traditional and semi-gasifier, including forced versus natural draft and fixed versus reciprocating grate). To assess the effects of fuel and stove type on PM2.5 composition, we measured elemental carbon (EC), organic carbon (OC), water-soluble OC, water-soluble inorganic ions (e.g. SO42-, Cl-, K+), and organic molecular markers. PM2.5 emissions from traditional stoves were mostly carbonaceous: 76-90% organic matter (OM), 5-6% EC, and less than 2% inorganic ions. In contrast, semi-gasifier stoves emitted more inorganic PM2.5: on average, ions comprised 65%, 9% was OM, and 4% was EC. Within the semi-gasifier cookstoves, forced-draft cookstove emissions had lower OM (1-3%) and higher ion concentrations (84-88%) than the natural-draft cookstove (5-14% OM, 30-83% ions). Levoglucosan was detected in PM2.5 from combustion of wood in the traditional cookstove and biomass pellets in the natural-draft semi-gasifier cookstove, but not from wood pellets in the forced-draft semi-gasifier cookstove. Across a range of different fuels and stoves, stove type influenced emitted PM composition more than fuel type, underscoring the impact of combustion conditions on PM chemical composition.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Carbono/análise , Carvão Mineral/análise , Glucose/análogos & derivados , Material Particulado/análise , Biomassa , Culinária , Glucose/análise , Utensílios Domésticos , Produtos Domésticos , Madeira/química
14.
Chemosphere ; 233: 879-887, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340414

RESUMO

Epidemiological studies have shown that fine particulate matter (PM2.5) has adverse impacts on human health. However, limited studies have investigated the effects of short-term exposure to PM2.5 and its constituents on mortality in China. This study used the generalized linear model (GLM) to investigate the effects of PM2.5 and its constituents, including organic carbon (OC), element carbon (EC), ammonium (NH4+), nitrate (NO3-), sulfate (SO42-), on different causes of mortality in Shanghai from January 1, 2013 to December 31, 2015. The single-day lagged model and the moving average lagged model were used to examine the lagging effects of pollutants on mortality. At lag0 day, PM2.5 had a significant effect on all-cause mortality, and a 10 µg/m3 increase leads to 0.68% increase in all-cause mortality (RR 1.0068, 95%CI 1.0013-1.0123). Among the five constituents, EC had the greatest impact on all-cause mortality in Shanghai, with 10.48% increase of mortality (RR 1.1048, 95%CI 1.0266-1.1891) per 10 µg/m3 increase of concentrations, followed by OC (RR 1.0577, 95%CI 1.0277-1.0886), NH4+ (RR 1.0272, 95%CI 1.0028-1.0522) and SO42- (RR 1.0104, 95%CI 1.0003-1.0206). For respiratory diseases mortality, EC, OC, NO3- and NH4+ had significant impacts and caused an increase of mortality by 44.99% (RR 1.4499, 95%CI 1.1813-1.7794), 10.40% (RR 1.1040, 95%CI 1.0260-1.1880), 5.338% (RR 1.0533, 95%CI 1.0097-1.0989) and 7.34% (RR 1.0734, 95%CI 1.0015-1.1505) per 10 µg/m3 increase of concentrations, respectively. The cumulative effect of PM2.5 on mortality was significant in Shanghai. Except for SO42-, the RR value of the single-day lagged model was smaller than the moving average lagged model.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental/efeitos adversos , Pneumopatias/induzido quimicamente , Pneumopatias/mortalidade , Material Particulado/análise , Compostos de Amônio/análise , Carbono/análise , China , Humanos , Modelos Lineares , Nitratos/análise , Sulfatos/análise
15.
Environ Pollut ; 252(Pt B): 1648-1658, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284207

RESUMO

Particulate matter (PM) deposited on canopy surfaces could be washed off and carried in throughfall to the ground. This would help plants recapture airborne PM on their canopy surfaces and then develop a PM purification capacity. Sixteen commonly greening plant species in north China (including 13 arbor species and 3 shrub species) were selected to investigate the washing process of plant-deposited PM during precipitation events. We measured the PM wash-off mass in throughfall under canopies of 16 plant species and in atmospheric precipitation during 14 precipitation events through field positioning experiments in 2015, compared the seasonal changes and species differences in PM wash-off mass, and discussed the predominant factors resulting in the variation. The results showed that plant-deposited PM was largely washed off by precipitation. The average wash-off mass of total suspended particulate (TSP) in throughfall was 1.3 times higher than that in precipitation, at 18.3 ±â€¯0.7 kg hm-2 and 7.9 ±â€¯0.9 kg hm-2, respectively. There were significant seasonal differences in TSP wash-off mass. The value was higher in summer at 22.3 ±â€¯1.0 kg hm-2, followed by that of winter (10.8 ±â€¯0.6 kg hm-2) and spring (8.9 ±â€¯1.0 kg hm-2). TSP wash-off mass in throughfall greatly varied among plant species (F = 9.542, n = 627, p < 0.001). Of the 16 selected species, Platanus acerifolia (38.0 ±â€¯5.8 kg hm-2) showed the largest difference from that of Liriodendron chinese (8.9 ±â€¯0.6 kg hm-2) (n = 80, p < 0.001). PM wash-off mass of different particle sizes in throughfall increased with the increase of event-based precipitation. This study enhanced the quantitative understanding of plant-deposited PM washed-off by natural precipitation among plant species and seasons. The results could provide significant guidelines for the selection and allocation of plant species to improve the PM retention capacity of urban greening plants.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Plantas/química , Chuva/química , Pequim , Tamanho da Partícula , Estações do Ano , Especificidade da Espécie , Urbanização
16.
Sci Total Environ ; 690: 151-157, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31284189

RESUMO

Haze pollution has significant impacts on tourist perception and behaviour, including a sharp increase in risk perception and a decline in tourism experience quality. However, given the intervention of multiple factors, whether these impacts necessarily have a negative effect on the overall scale of regional tourism remains unknown. Hence, this paper explored the overall effect of haze pollution on domestic travel. Using 28 major cities in China as examples, we employed a two-way fixed effect panel model to investigate this issue. Combined with the comparisons between the results of different subgroups, including high cities, medium cities, low cities, outbreak cities and non-outbreak cities, this study found that there was no significant effect of haze concentration on domestic travel, but public awareness of haze pollution had a significant positive effect on that. Meanwhile, public awareness exerted a negative moderating effect of haze concentration and domestic travel. The findings are beneficial for understanding the new situation faced by the tourism industry, and several suggestions are provided for policy makers and travel agencies.


Assuntos
Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Viagem , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Material Particulado/análise
17.
Sci Total Environ ; 690: 76-84, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31284198

RESUMO

Interactions of particulate matter (PM) and respiratory tract play a crucial role in PM-related respiratory diseases. The majority of the work focuses on the oxidative stress induced by reactions between PM-borne redox-active components and lung lining fluid (LLF). The effects of PM-borne biological components are largely unknown. Of all PM-borne biologicals, bacteria, as living microorganisms, are closely related with inflammatory immune responses. However, its inhalation risk is usually determined without considering the respiratory physiological conditions. In this study, a surrogate lung fluid (SLF) with four typical antioxidants was applied to characterize the ambient bacteria, including concentrations of total bacteria/viable bacteria/culturable bacteria, metabolic activity, bacteria-derived endotoxin, as well as the community structure. Comparing to those determined by SLF, we find that use of PBS leads to an underestimation of the bacterial culturability and metabolic activity. No effect was seen regarding the number of total bacteria and viable bacteria (with intact membrane). Population structure change was seen for bacteria cultured from SLF-collected samples, when compared to that from PBS. Spore-forming bacteria, e.g., genus Bacillus, were found to be easily recovered with SLF. This implies that use of PBS could underestimate the bacteria inhalation risk, especially those bacterial endospores. Our work highlights the necessity to consider the respiratory airway environment when evaluating microbial inhalation risk.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Poluição do Ar , Antioxidantes , Bactérias , Endotoxinas , Exposição por Inalação , Pulmão , Oxirredução , Estresse Oxidativo , Tamanho da Partícula , Doenças Respiratórias
18.
Ecotoxicol Environ Saf ; 182: 109386, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31255868

RESUMO

It is highly significant to develop efficient soft sensors to estimate the concentration of hazardous pollutants in a region to maintain environmental safety. In this paper, an air quality warning system based on a robust PM2.5 soft sensor and support vector machine (SVM) classifier is reported. The soft sensor for the estimation of PM2.5 concentration is proposed using a novel approach of Bayesian regularized neural network (BRNN) via forward feature selection (FFS). Zuoying district of Taiwan is selected as the region of study for implementation of the estimation system because of the high pollution in the region. Descriptive statistics of various pollutants in Zuoying district is computed as part of the study. Moreover, seasonal variation of particulate matter (PM) concentration is analyzed to evaluate the impact of various seasons on the increased levels of PM in the region. To investigate the linear dependence of concentration of different pollutants to the concentration of PM2.5, Pearson correlation coefficient, Kendall's tau coefficient, and Spearman coefficient are computed. To achieve high performance for the PM2.5 estimation, selection of appropriate forward features from the input variables is carried out using FFS technique and Bayesian regularization is incorporated to the neural network system to avoid the overfitting problem. The comparative evaluation of performance of BRNN/FFS estimation system with various other methods shows that our proposed estimation system has the lowest mean square error (MSE), root mean square error (RMSE), and mean absolute error (MAE). Moreover, the coefficient of determination (R-squared) is around 0.95 for the proposed estimation method, which denotes a good fit. Evaluation of the SVM classifier showed good performance indicating that the proposed air quality warning system is efficient.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Teorema de Bayes , Monitoramento Ambiental/estatística & dados numéricos , Redes Neurais (Computação) , Estações do Ano , Taiwan
19.
Environ Pollut ; 253: 181-189, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31306825

RESUMO

This work explores the use of Raman micro-spectroscopy to determine sources of airborne particulate matter collected on PM2.5 air filters in Imperial Valley, California. The goal is to examine if nearby soil is a potential source of particles sampled on air filters deployed in an urbanized desert area during events of unusually high PM2.5 excursions. Particle specific composition information can be an indicator of potential origin. This can provide insights into the source of unexpectedly high proportion of large particles sampled on PM2.5 filters in the vicinity of Imperial Valley. The measured spectral correspondence between the filter and soil particles, in the size range of 2.5-10 µm, is consistent with windblown dust being a likely source of the larger (>2.5 µm) particles collected on the PM2.5 filters. Additionally, these particles were identified as components of commonly occurring crustal minerals in the vicinity of the sampling site, such as iron oxides, hydroxides, sulfides, titanium dioxides and aluminosilicates. A substantial portion of the analyzed filter particles displayed a strong broadband fluorescence signal, which is consistent with the presence of organic matter and has been recognized as a marker for soil related origin of the filter particles. Elemental carbon (soot) was found to be prevalent among the particles as well, suggesting the existence of combustion related sources. Comparison between a heavily loaded filter sample and a filter with a more typical, lower loading did not show any obvious difference in chemical compositions. In both cases the particles appeared to be of crustal origin with the prevalence of elemental carbon. The primary difference between these two filter samples appear to be their particle size distribution - the heavily loaded filter sample contained greater proportion of large particles (>2.5 µm), and was more consistent with spectral signature of soils analyzed from the region.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Solo , Filtros de Ar , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , California , Carbono/análise , Poeira/análise , Tamanho da Partícula , Análise Espectral
20.
Environ Pollut ; 253: 190-198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310869

RESUMO

Increased public awareness of the health impacts of atmospheric fine particulate matter (PM2.5) has led to increased demand and deployment of indoor air cleaners. Yet, questions still remain about the effectiveness of indoor air cleaners on indoor PM2.5 concentrations and personal exposure to potentially hazardous components of PM2.5. Metals in PM2.5 have been associated with adverse health outcomes, so knowledge of their sources in urban indoor and outdoor areas and how exposures are influenced by indoor air cleaners would be beneficial for public health interventions. We collected 48-h indoor, outdoor, and personal PM2.5 exposure samples for 43 homes with asthmatic children in suburban Shanghai, China during the spring months. Two sets of samples were collected for each household, one set with a functioning air filter placed in the bedroom ("true filtration") and the other with a non-functioning ("sham") air cleaner. PM2.5 samples were analyzed for elements, elemental carbon, and organic carbon. The major sources of metals in PM2.5 were determined by Positive Matrix Factorization (PMF) to be regional aerosol, resuspended dust, residual oil combustion, roadway emissions, alloy steel abrasion, and a lanthanum (La) and cerium (Ce) source. Under true filtration, the median indoor to outdoor percent removal across all elements increased from 31% to 78% and from 46% to 88% across all sources. Our findings suggest that indoor air cleaners are an effective strategy for reducing indoor concentrations of PM2.5 metals from most sources, which could translate into improved health outcomes for some populations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Exposição Ambiental/análise , Metais/análise , Aerossóis , Filtros de Ar , Poluição do Ar em Ambientes Fechados/análise , Criança , China , Poeira , Monitoramento Ambiental , Filtração , Humanos , Material Particulado/análise , Estações do Ano
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