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1.
Sci Total Environ ; 713: 136428, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32019009

RESUMEN

This study was designed to evaluate the occurrence and variation in concentrations, sources and cancer risk of PM2.5-bound PAHs. Airborne PM2.5-bound PAHs were sampled during a one-year campaign (2014-2015) in Anshan city, a typical iron and steel city in northeast China. A total of 374 PM2.5 samples were collected. A source-oriented positive matrix factorization (PMF) model and PAH diagnostic ratios were used to investigate the potential sources of PAHs in the atmospheric environment of Anshan, and the lifetime cancer risk of the population associated with PAHs through inhalation exposure was assessed by a PMF-ILCR model. Concentrations of PM2.5 and 16 PAHs ranged from 13.55 µg/m3 to 315.96 µg/m3 and 5.08 ng/m3 to 520.02 ng/m3, respectively. These values were higher in winter. PAH content from stationary sources and biomass combustion was higher than from other sources. Through the coefficient of divergence and localized PAH diagnostic ratio methods, we concluded that PM2.5-bound PAHs in Anshan originated mainly from the following sources: biomass combustion, vehicle emissions, fugitive dust, coking dust and natural gas emissions. Based on the source-oriented PMF model, coal combustion, fugitive dust, vehicle emissions, coking dust, and biomass combustion were the main sources contributing to PM2.5, accounting for 26.3%, 24.6%, 21.9%, 18.0%, and 6.3% of PM2.5, respectively. According to the PMF-ILCR model results, ILCR risks estimated for adults and children were respectively 1.19 × 10-5 and 8.55 × 10-6 in winter, higher than in other seasons, and higher than the threshold value (10-6). Together, vehicle emissions (diesel exhaust and gasoline exhaust), coal combustion and coking dust, contributed to over 86% of the cancer risk associated with PM2.5-bound PAHs exposure in Anshan.


Asunto(s)
Material Particulado/análisis , Contaminantes Atmosféricos , China , Ciudades , Monitoreo del Ambiente , Humanos , Hierro , Hidrocarburos Policíclicos Aromáticos , Medición de Riesgo , Estaciones del Año , Acero , Emisiones de Vehículos
2.
Chemosphere ; 243: 125440, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31995888

RESUMEN

To date no study has been able to clearly attribute the observed toxicological effects of atmospheric particles (PM) to a specific class of components. The toxicity of both the organic extractable matter (OEM2.5-0.3) and non-extractable matter (NEM2.5-0.3) of fine particles (PM2.5-0.3) was compared to that of PM2.5-0.3 in its entirety on normal human epithelial bronchial BEAS-2B cells in culture. The specific effect of the quasi-ultrafine fraction (PM0.3) was assessed, by comparing the responses of cells exposed to the PM2.5-0.3 and PM0.3 organic extractable matter, OEM2.5-0.3 and OEM0.3 respectively. Chemically, PAH, O-PAH, and N-PAH were respectively 43, 17, and 4 times more concentrated in PM0.3 than in PM2.5-0.3, suggesting thereby a predominant influence of anthropogenic activities and combustion sources. BEAS-2B cells exposed to PM2.5-0.3, NEM2.5-0.3, EOM2.5-0.3 and OEM0.3 lead to different profiles of expression of selected genes and proteins involved in the metabolic activation of PAH, O-PAH, and N-PAH, and in the genotoxicity pathways. Specifically, OEM0.3 was the most inducer for phase I and phase II enzymes implicated in the metabolic activation of PAH (AHR, AHRR, ARNT, CYP1A1, CYP1B1, EPHX-1, GSTA-4) thereby producing the highest DNA damage, felt by ATR and, thereafter, a cascade of protein phosphorylation (CHK1/CHK2/MDM2) closely related to the cell cycle arrest (P21 and P53 induction). This study underlined the crucial role played by the organic chemicals present in PM0.3. These results should be considered in any future study looking for the main chemical determinants responsible for the toxicity of ambient fine PM.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Células Epiteliales/efectos de los fármacos , Material Particulado/toxicidad , Contaminantes Atmosféricos/análisis , Bronquios/citología , Línea Celular , Daño del ADN , Humanos , Compuestos Orgánicos/toxicidad , Tamaño de la Partícula , Material Particulado/análisis
3.
Environ Monit Assess ; 192(2): 88, 2020 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-31900672

RESUMEN

The formation of an oil-suspended particulate material aggregate (OSA) is one of the weathering processes that occur after the spill of oil in marine environments, responsible for the dispersion of hydrocarbons. Oil and particle aggregates are formed from the interaction between small oil droplets and suspended particulate matter (SPM). In general, SPM are fine particles which may be inorganic minerals or organic particles in the water column. OSAs provide vertical dispersion of oil along the water column depending on the acquired density (buoyancy), and may remain near the surface, water column, or bottom of water bodies. The present study examines the formation of these aggregates through the laboratory simulation of an oil spill in the waters of the São Paulo river estuary. The main objective was to investigate the dispersion of polycyclic aromatic hydrocarbons (PAHs), verifying which estuary characteristics most influenced the formation of OSAs and in addition to determine the regions of probable ecotoxicological impact due to the negative buoyancy of the formed aggregate. The results show that there was greater dispersion to the water column, mainly of lighter PAHs, ranging from 85,804.05 ng g-1 (P11C) to 566,989.84 ng g-1 (P17C). The percentage of dispersed PAH concentration per experimental unit ranged from 9.90% in unit P2 to 75.27% in unit P18. The formation of OSAs was influenced mainly by salinity and chlorophyll a. As the most vulnerable regions, the impacts are one mouth (P2 and P4), one central region (P7, P8, and P10), and one source (P18).


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Clorofila A , Ecotoxicología , Estuarios , Sedimentos Geológicos , Material Particulado/análisis , Contaminación por Petróleo/análisis , Ríos , Salinidad
4.
Environ Monit Assess ; 192(2): 90, 2020 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-31902018

RESUMEN

Owing to the rise in population, lifestyle changes, high traffic rates in urban areas and environmental pollution, respiratory diseases have become much more prevalent on both regional and urban scales. Respiratory diseases affect over 300 million people worldwide and are thus among the major threats to humans' general well-being. The identification of underlying factors and the specification of accompanying risk areas for the temporal exacerbation of respiratory diseases are effective steps in managing the damage caused by such disorders. Here, we demonstrate a strategy for modelling the risk zone of respiratory diseases temporally, using a location-based social network (LBSN) and an artificial neural network (ANN). The main contribution of this paper is to consider the environmental and infrastructural factors and identify their relationships with the geographical locations of respiratory attacks. The study also utilizes Telegram, which is the most popular and conventional social media platform, in order to observe temporal changes in the location of respiratory attacks in Iran, in the form of a developed Telegram bot known as @respiratoryassociation. The relations between the factors behind and the location of respiratory attacks are determined using a multilayer perceptron (MLP) ANN. All the required data have been collected on a daily basis over a 5-year period from December 2013 to December 2018 in Tehran, Iran. The results indicated air pollution, especially pollution from carbon monoxide (CO) and suspended particulate matter (PM) as the most decisive factors. Following air pollution, the amount of exposure to the polluted area was determined as the second most decisive factor, which in turn increased as a result of escalations in traffic jams. Land use was determined as the third most decisive factor. Furthermore, the results revealed that the ANN performed satisfactorily, implying that the model can be used to examine the spatio-temporal behaviour of the time series of respiratory diseases with respect to environmental and infrastructural factors.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Enfermedades Respiratorias/epidemiología , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Monóxido de Carbono , Progresión de la Enfermedad , Monitoreo del Ambiente , Contaminantes Ambientales , Humanos , Irán , Material Particulado/análisis , Prevalencia
5.
Environ Monit Assess ; 192(2): 95, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31907629

RESUMEN

With the acceleration of urbanization and industrialization, atmospheric pollution has become a major issue, restricting the sustainable development of the urban environment. Since 2013, Beijing has been among China's most seriously affected regions in terms of haze pollution. Atmospheric pollution is closely linked to land use, particularly the spatial patterns of green and urban land. Therefore, the quantification of the relationship between fine particulate matter (PM2.5) concentration and its driving factors in Beijing is of considerable significance for environmental management and spatial epidemiological studies. A land use regression (LUR) model was constructed to simulate the spatio-temporal distribution of PM2.5 concentration. In this study, the independent variables (driving factors) included land use, meteorological factors, population, roads, the digital elevation model, and the normalized difference vegetation index. The five models had adjusted R2 of 0.887, 0.770, 0.742, 0.877, and 0.798, respectively. Land use and meteorological factors were the main factors affecting PM2.5 concentration. The driving factors of land use on a large scale and roads on a small scale had a significant impact on PM2.5 emissions. Beijing's PM2.5 concentrations in 2015 showed clear spatio-temporal characteristics. The highest (lowest) average PM2.5 concentration was recorded in winter (summer). In terms of spatial distribution, PM2.5 concentrations showed a "low in the northwest and high in the southeast" trend. The most polluted areas were mainly distributed in the central city and the southeastern and southwestern regions. The PM2.5 concentration boundary was essentially consistent with the boundary of land use type. Different land use types promoted or inhibited PM2.5 concentrations, with a difference of more than 20 µg/m3 PM2.5 between the two land use categories. Thus, PM2.5 concentrations should be controlled by optimizing the spatial and temporal patterns of land use.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Material Particulado/análisis , Beijing , China , Planificación de Ciudades , Estaciones del Año , Urbanización
6.
Environ Monit Assess ; 192(2): 104, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31915931

RESUMEN

In southern Chile, epidemiological studies have linked high levels of air pollution produced by the use of wood-burning stoves with the incidence of numerous diseases. Using a quasi-experimental design, this study explores the potential of participatory sensing strategies to transform experiences, perceptions, attitudes, and daily routine activities in 15 households equipped with wood-burning stoves in the city of Temuco, Chile. The results suggest that the experience of using a low-cost sensor improves household members' awareness levels of air pollution. However, the information provided by the sensors does not seem to improve the participants' self-efficacy to control air quality and protect themselves from pollution. The high degree of involvement with the participatory sensing experience indicates that the distribution of low-cost sensors could be a key element in the risk communication policies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Contaminación del Aire Interior/prevención & control , Chile , Ciudades , Participación de la Comunidad , Monitoreo del Ambiente/instrumentación , Humanos , Madera/química
7.
Environ Monit Assess ; 192(2): 116, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31942665

RESUMEN

Serious air pollution motivates governments to take control measures. However, specific emission reduction effects of various temporary emission reduction policies are difficult to evaluate. During the Asia-Pacific Economic Cooperation meeting in Beijing in 2014, the Chinese government implemented a number of emergency emission control measures in the Beijing-Tianjin-Hebei area to maintain the air quality in this region. This gave us an opportunity to quantify the effectiveness of the emission reduction measures separately and identify the efficient policy combinations for the reduction of major pollutants. In this study, we evaluated the impacts of specific emission reduction measures on the concentrations of two major air pollutants (PM2.5 and O3) under eight policy scenarios using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). Comparing these scenarios, we found that the control policies against the primary PM2.5 emission achieved the most significant results. Meanwhile, all the emission control measures raised the ozone concentrations in different degrees, which might be partly attributed to the changes of PM2.5 concentration and the ratio of NOx and VOCs caused by the emission control measures. Our results suggest that, in VOC-sensitive areas like Beijing, emergency control measures focusing on primary PM2.5 emission could lead to significant PM2.5 reduction and relatively small ozone increase, and should be considered as a priority policy. Joint emission control at the regional scale is also important especially under unfavorable meteorological conditions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/prevención & control , Política Ambiental , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Asia , Beijing , China , Monitoreo del Ambiente , Ozono/análisis , Material Particulado/análisis
8.
Environ Sci Pollut Res Int ; 27(8): 8395-8405, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31902078

RESUMEN

The particle penetration factor is an important parameter to determine the concentration of indoor particles. In this paper, a mathematical model for calculating this parameter was established by combining with the decay of the indoor PM2.5 and CO2 concentrations measured in a bedroom with an air cleaner. The convergence of the penetration factors was analyzed under different working conditions. The results show that the particle penetration factors converge to stable values within the range of 0.69 to 0.84 close to the value from the empirical formula when the indoor PM2.5 concentration decays to stable values. When the role of particle deposition is ignored, the penetration factors at the low and middle airflow modes are 0.78 and 0.69, respectively. The particle penetration factors are mainly determined by the clean air delivery rate (CADR) of the air cleaner, clearance airflow, and I/O ratio during the balanced phase when the roles of indoor particle deposition and exfiltration can be ignored. This work can provide a convenient method for the calculation of the particle penetration factor.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Tamaño de la Partícula , Material Particulado/análisis , Material Particulado/química
9.
Chemosphere ; 242: 125196, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31896208

RESUMEN

Lanzhou, an ex-heavily polluted city, was awarded "The Award for Today's Transformative Step" in 2015 World Climate Conference at Paris for its great efforts on air quality improvement since 2012. However, the health benefits from this improvement remain unclear. Therefore, we collected time-series data covering deaths, weather variables and air pollutants during the two periods (2004-2009, 2014-2017) and fitted single-pollutant models using the generalized additive models to evaluate the change of mortality risks associated with air pollutants in Lanzhou. Results showed that the annual average concentrations of respirable particulate matter (PM10) and sulfur dioxide (SO2) dropped by 19.28% and 66.29%, while the nitrogen dioxide (NO2) increased by 16.61% in 2014-2017 compared to 2004-2009. During the period 2004-2009, we found a 10-µg/m3 increase in PM10 (lag 2), SO2 (lag 0-5) and NO2 (lag 0-5) were associated with mortality increments of 0.12% (95% CI: 0.01, 0.22), 0.86% (95% CI: 0.42, 1.31) and 1.29% (95% CI: 0.70, 1.90), respectively. During the period 2014-2017, the association between PM10 and daily deaths was not significant, but we observed a 10-µg/m3 increase in SO2 (lag 0-5) and NO2 (lag 4) were related to mortality increments of 4.23% (95% CI: 1.82, 6.70) and 0.85% (95% CI: 0.19, 1.52), respectively. From 2004-2009 to 2014-2017, we observed markedly decline of mortality risk due to PM10, but not SO2 or NO2. In conclusion, the mortality risk of PM10 in Lanzhou has declined obviously after the substantially improved air quality due to the enforcement of air pollution controlling policies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Mortalidad/tendencias , Contaminación del Aire/análisis , China/epidemiología , Clima , Contaminantes Ambientales , Humanos , Dióxido de Nitrógeno/análisis , Material Particulado/análisis , Dióxido de Azufre/análisis , Tiempo (Meteorología)
10.
Chemosphere ; 242: 125299, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31896194

RESUMEN

The physicochemical characteristics are different for suspended particles (SPS) with different sizes in rivers. Here, we studied the effect of SPS (1 g L-1) with three different sizes (63-106 µm, 20-63 µm, and <20 µm) on the bioaccumulation of deuterated polycyclic aromatic hydrocarbons (phenanthrene-d10, anthracene-d10, fluoranthene-d10 and pyrene-d10) in zebrafish using passive dosing devices to maintain the freely dissolved concentrations of PAHs-d10 constant in water. The results showed that all the three grain size SPS could be ingested by zebrafish, and there was no significant difference in the amount of ingested SPS among the three grain sizes. The concentrations (lipid-normalized or not) of PAHs-d10 in zebrafish were promoted in the presence of the three different size SPS, and the PAH-d10 concentrations in zebrafish increased with decreasing particle size. Compared with the systems without SPS, the lipid-normalized concentrations of PAHs-d10 increased by 12%-72%, 34%-130%, and 60%-196%, respectively in zebrafish in systems with 63-106 µm, 20-63 µm, and <20 µm of SPS after exposure for 20 h. The stronger effect of SPS with smaller grain sizes was probably due to their lower organic carbon content, lower ratio of black carbon to organic carbon content, smaller particle size, and higher dissolved organic matter contents, which could promote the desorption of PAHs-d10 from ingested SPS and bioaccessibility of PAHs-d10 to zebrafish. This study suggests that in addition to SPS concentration, the suspended particle size should be considered in ecological risk assessment for hydrophobic organic compounds in aquatic environment.


Asunto(s)
Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Pez Cebra/metabolismo , Animales , Bioacumulación , Sedimentos Geológicos/química , Modelos Teóricos , Tamaño de la Partícula , Material Particulado/química , Hidrocarburos Policíclicos Aromáticos/química , Contaminantes Químicos del Agua/química
11.
Chemosphere ; 241: 125133, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31683427

RESUMEN

Black carbon (BC) plays a vital role in atmospheric environment and climate change. Temporal variations and transport pathways of BC in Xiamen, China with the impacts of synoptic circulation were investigated in 2014 with Aethalometer. Annual mean BC concentration was 4270 ng m-3. BC exhibited clear diurnal (seasonal) variations, with the maximum of 6182 (4755) ng m-3 at 6:00 (in spring) and minimum of 2847 (3774) ng m-3 at 13:00 (in summer). Conditional probability function analysis indicated that high BC concentrations were associated with northwesterly winds with low wind speed. Air masses originating from the East China Sea and passing along with East China Coast had the highest BC concentrations. Potential source contribution function and concentration weighted trajectory analysis suggested that major sources for BC included the surrounding region, southwestern Fujian and eastern Guangdong to the southwest, Hubei, Hunan and Jiangxi to the northwest, the East China Sea and the South China Sea. Of the nine synoptic circulation patterns, three cyclone-related patterns were associated with low BC concentrations and small biomass burning (BCbb) contributions. Of the six anticyclone-related patterns, the three cold-high circulations around winter were associated with moderate BC concentrations and large BCbb contributions. The two cold-high patterns in spring and autumn were associated with high BC concentrations and small BCbb contributions, while the warm-high pattern was associated with moderate BC concentration and small BCbb contribution. The findings provide insights into the transport mechanisms of BC with the impacts of synoptic pattern in China.


Asunto(s)
Monitoreo del Ambiente/métodos , Estaciones del Año , Hollín/análisis , Viento , Contaminantes Atmosféricos/análisis , China , Material Particulado/análisis
12.
Chemosphere ; 241: 125127, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31683440

RESUMEN

Atmospheric particulate matter (PM2.5) is associated with the morbidity and mortality of cardiovascular diseases. However, whether PM2.5 penetrates into the cells and the potential mechanisms are unknown. Hence, the study firstly indicated that PM2.5 could penetrate into the HUVEC cells, and phagocytosis, micropinocytosis, caveolin as well as clathrin mediated the internalization of PM2.5 into HUVEC cells. Particularly, the components of PM2.5-Metal, PAHs and WSC could enter into HUVEC cells mainly via the micropinocytosis, clathrin and caveolin mediated endocytosis, respectively. The current data of environmental assessments indicated that PM2.5-Metal were extremely harmful to the ecological environment and human health. Moreover, accompanying with mitochondrial fusion gene Mfn1 was increased and fission genes Opa1 and Drp1 were decreased, and the lysosome related genes LAMP2 and LAMP3 were decreased, the phenomenon that the morphology of mitochondrial and lysosome injured was observed in HUVEC cells treated with PM2.5 and/or PM2.5-Metal. These data suggest that PM2.5 and its main components depend on different endocytosis penetrate into HUVEC cells and cause the mitochondrial and lysosomal damages. Thereby, our study provides the potential mechanism of haze particles penetration into HUVEC cells and damage to organelles.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Material Particulado/toxicidad , Contaminantes Atmosféricos/análisis , Células Endoteliales de la Vena Umbilical Humana/patología , Células Endoteliales de la Vena Umbilical Humana/ultraestructura , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Dinámicas Mitocondriales/efectos de los fármacos , Dinámicas Mitocondriales/genética , Orgánulos/efectos de los fármacos , Orgánulos/patología , Tamaño de la Partícula , Material Particulado/análisis
13.
Environ Pollut ; 256: 113390, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31706768

RESUMEN

With increasingly severe air pollution, the aggravated health risks of particulate matter, especially ultrafine particles, are emerging as an urgent and sensitive topic. Considering the heterogeneity and complexity of ultrafine particles, there is insufficient evidence about their toxic effects and possible molecular mechanisms. To address this question, we analyzed the emission characteristics of quasi-ultrafine particles collected during winter in a typical coal-burning city, Taiyuan, and confirmed their contribution to lung cancer cell adhesion and metastasis. For the specific mechanism, we revealed that the endocytosis of quasi-ultrafine particles stimulated the release of HMGB1, induced NFκB-facilitated proinflammatory cytokine production through the interaction of HMGB1 with RAGE, and resulted in cancer-endothelial cell adhesion. These findings remind us of the potential effects of anthropogenic quasi-ultrafine particle pollution and provide a theoretical reference for the mitigation of tumorigenesis in a severe particulate matter contaminated environment.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Adhesión Celular/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Proteína HMGB1/metabolismo , Material Particulado/toxicidad , Células A549 , Contaminantes Atmosféricos/análisis , China , Carbón Mineral , Endocitosis/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Tamaño de la Partícula , Material Particulado/análisis , Propiedades de Superficie
14.
Environ Pollut ; 256: 113419, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31706769

RESUMEN

Ozone has become a major atmospheric pollutant in China as the pattern of urban energy usage has changed and the number of motor vehicles has grown rapidly. The Beijing-Tianjin-Hebei Urban Agglomeration, also known as the Jing-Jin-Ji Urban Agglomeration (hereafter, JJJUA), with a precarious balance between protecting the ecological environment and sustaining economic development, is challenged by high levels of ozone pollution. Based on ozone observation data from 13 cities in the JJJUA from 2014 to 2017, the spatio-temporal trends in the evolution of ozone pollution and its associated influencing factors were analyzed using Moran's I Index, hot-spot analysis, and Geodetector using ArcGIS and SPSS software. Five key results were obtained. 1) There was an increase in the annual average ozone concentration, for the period 2014-2017. Comparing the 13 prefecture-level cities, ozone pollution in Chengde and Hengshui decreased, while it worsened in the remaining 11 cities. 2) Ozone pollution was worse in spring and summer than in autumn and winter; the peak ozone pollution season was from May to September; the average ozone concentration on workdays was higher than that on non-workdays, showing a counter-weekend effect. 3) Annual average concentrations were high in the central and southern parts of the study region but low in the north. 4) Prominent positive spatial correlations were observed in ozone concentration, with the best correlations shown in summer and autumn; concentrations were high in Baoding and Xingtai but low in Beijing and Chengde. 5) Concentrations of PM10, NO2, CO, SO2, and PM2.5, as well as average wind speed, sunshine duration, evaporation, precipitation, and temperature, all had significant effects on ozone pollution, and interactions between these influencing factors increased it.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Ozono/análisis , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Beijing , China , Ciudades , Desarrollo Económico , Material Particulado/análisis , Estaciones del Año , Viento
15.
Environ Pollut ; 256: 113395, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31708281

RESUMEN

We apply convolutional neural network (CNN) model for estimating daily 24-h averaged ground-level PM2.5 of the conterminous United States in 2011 by incorporating aerosol optical depth (AOD) data, meteorological fields, and land-use data. Unlike some of the recent supervised learning-based approaches, which only utilized the predictors from the location of which PM2.5 value is estimated, we naturally aggregate predictors from nearby locations such that the spatial correlation among the predictors can be exploited. We carefully evaluate the performance of our method via overall, temporally-separated, and spatially-separated cross-validations (CV) and show that our CNN achieves competitive estimation accuracy compared to the recently developed baselines. Furthermore, we develop a novel predictor importance metric for our CNN based on the recent neural network interpretation method, Layerwise Relevance Propagation (LRP), and identify several informative predictors for PM2.5 estimation.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Aerosoles/análisis , Meteorología , Estados Unidos
16.
Environ Pollut ; 256: 113403, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31711721

RESUMEN

Both air pollution and dyslipidemias contributed to large number of deaths and disability-adjusted life lost years. Long-term air pollution exposure was related to changed blood lipids and risk of dyslipidemias. This study was designed to evaluate relationships between air pollutants, blood lipids and prevalence of dyslipidemias in a Chinese rural population exposed to high-level air pollution based on baseline data of The Henan Rural Cohort study. An amount of 39,057 participants from rural areas in China were included. The 3-year average exposure of air pollutants (PM2.5, PM10, NO2) was estimated by a spatiotemporal model. Logistic and linear regression models were employed to explore relationships between air pollutants, blood lipids (TC, TG, HDL-C and LDL-C) and prevalence of dyslipidemias. The three-year concentration of PM2.5, PM10 and NO2 was 72.8 ±â€¯2.3 µg/m3, 131.5 ±â€¯5.7 µg/m3and 39.1 ±â€¯3.1 µg/m3, respectively. Overall, increased air pollution exposure was related to increased TC and LDL-C, while decreased TG and HDL-C. Each 1-µg/m3 increment of PM2.5 was related to 0.10% (0.07%-0.19%) increase in TC, 0.63% (0.50%-0.77%) increase in LDL-C, 2.93% (2.70%-3.16%) decrease in TG, 0.49% (0.38%-0.60%) decrease in HDL-C; and 5.7% (95%CI: 3.7%-7.6%), 4.0% (95%CI: 2.1%-6.0%) and 3.8% (95%CI: 2.5%-5.1%) increase in odds for hypercholesterolemia, hyperbetalipoproteinemia and hypoalphalipoproteinemia, respectively. Stronger associations were found in male and older participants. Findings suggest that air pollutants were associated with changed blood lipid levels and higher risk of dyslipidemias among rural population. Male and elder people should pay more attention to personal safety protection.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Dislipidemias/epidemiología , Exposición a Riesgos Ambientales/análisis , Lípidos/sangre , Anciano , Contaminación del Aire/análisis , Grupo de Ascendencia Continental Asiática , China/epidemiología , Estudios de Cohortes , Exposición a Riesgos Ambientales/estadística & datos numéricos , Femenino , Humanos , Modelos Lineales , Masculino , Material Particulado/análisis , Prevalencia , Población Rural , Tiempo
17.
Chemosphere ; 242: 125226, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31698210

RESUMEN

PM2.5 and PM10 samples were collected in the semi-arid city of Xi'an in Northwest China from November 2016 to November 2017 and analyzed to assess pollution characteristics, sources, health risks, and influencing factors of 6 priority phthalate esters (PAEs). The results showed that the sum of the 6 PAEs (Σ6PAEs) was 85.5 ng m-3 in PM2.5 and 94.5 ng m-3 in PM10, being higher at the suburban site than the urban site and winter > spring > summer > autumn. The most abundant PAE was bis(2-ethylhexyl phthalate) (DEHP). PM2.5- and PM10-bound PAEs were associated mainly with the use of plasticizers plus the uses of cosmetics and personal care products, construction materials, and home furnishings. Temperature, relative humidity, and visibility had stronger influences on the concentrations of PM and PM-bound PAEs than pressure and wind speed. Pressure and relative humidity were positively correlated with the concentrations of PM and most of the PM-bound PAEs, while temperature, visibility and wind speed had negative correlations with the concentrations of PM and PM-bound PAEs. The non-carcinogenic risks of human inhalation exposure to PM-bound PAEs were in the range of 10-7 to 10-3, suggesting low non-cancer risks, which were higher at the suburban site than the urban site and higher to children than adults. The cancer risks of human inhalation exposure to PM-bound DEHP and butyl benzyl phthalate (BBP) were in the range of 10-12 to 10-10, suggesting low carcinogenic risks, being in the order of the suburban site > the urban site and DEHP > BBP. Special attention should be paid to long-term low dose exposure to PAEs in the suburb, especially in winter and spring.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Material Particulado/análisis , Ácidos Ftálicos/análisis , Adulto , Niño , China , Ciudades , Ésteres/análisis , Humanos , Exposición por Inhalación/análisis , Plastificantes/análisis , Medición de Riesgo , Estaciones del Año
18.
Chemosphere ; 242: 125132, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31669986

RESUMEN

The present study was conducted at sub-urban and rural site of Agra. The main aim of this study was to characterize WSII in terms of spatial, seasonal and formation characteristics and identify the major sources responsible for the pollution of WSII in PM2.5 particles using different source apportionment models. Since biomass burning is one of the most important sources of PM2.5 pollution in Agra, a case study was also conducted at rural site to investigate the contribution of biomass burning from cooking activities using different types of fuels. PM2.5 mass concentrations were higher at sub-urban site (91.0 ±â€¯50.8 µg/m3) than at rural site (77.1 ±â€¯48.6 µg/m3). WSII contributed 50.0% and 45.8% of annual average PM2.5 mass at both sites. The aerosols were ammonium rich and were therefore alkaline in nature. Aerosol acidity characteristics studied using AIM-II model showed that the aerosols were slightly less acidic at rural site than at sub-urban site. SO42-, NO3- and NH4+ were the major contributors of WSII and their formation was favoured mainly in winter. Although, WSII showed slight variations in seasonal and spatial characteristics, the major sources of pollution were found to be similar. Four sources were identified as biomass burning (29.1% and 27.4%), secondary aerosols (26.2% and 22.5%), coal combustion (22.3% and 26.9%) and soil dust (22.4% and 23.1%) at sub-urban and rural sites. The results of case study showed that among different types of biomass fuels cow dung cakes showed maximum PM2.5 emissions while LPG showed minimum PM2.5 emissions.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Compuestos de Amonio , Animales , Biomasa , Bovinos , Carbón Mineral/análisis , Culinaria , Polvo/análisis , Estaciones del Año , Suelo , Emisiones de Vehículos/análisis
19.
Environ Pollut ; 256: 113340, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31662257

RESUMEN

BACKGROUND: Evidence of health effects following early life exposure to short-to-medium duration of high pollution levels is extremely limited. OBJECTIVES: We aimed to evaluate the associations between: 1. intrauterine exposure to fine particulate matter (PM2.5) from coal mine fire emissions and the frequencies of general practitioner attendances and dispensations of prescribed asthma inhalers, steroid skin creams, and antibiotics during the first year of life; 2. infant exposure and those outcomes during the year following the fire. METHODS: All participants were recruited from the Latrobe Valley of Victoria, Australia. Participants' 24-h average and hourly peak mine fire-specific PM2.5 exposures from 09/02/2014 to 31/03/2014 were estimated using chemical transport modelling. Outcome data were obtained from the Australian Medicare Benefits Schedule and Pharmaceutical Benefits Scheme from each child's birth to 31/12/2016. We used negative binomial and logistic regression models to independently assess risks of the outcomes associated with every 10 and 100 µg m-3 increase in average or peak PM2.5 exposure, respectively, while adjusting for potential confounders. RESULTS: We included 286 of 311 children whose parents consented to be linked, comprising 77 with no exposure, 88 with intrauterine exposure and 121 with exposure in infancy. 10- and 100- µg m-3 increases in average and peak PM2.5 exposure during infancy were associated with greater incidence of antibiotics being dispensed during the year following the fire: the adjusted incidence rate ratios were 1.24 (95% CI 1.02, 1.50, p = 0.036) and 1.14 (1.00, 1.31, p = 0.048) respectively. No other significant associations were observed. CONCLUSION: Exposure to coal mine fire emissions during infancy was associated with increased dispensing of antibiotics. This could reflect increased childhood infections or increased prescriptions of antibiotics in the year following the fire.


Asunto(s)
Contaminación del Aire/análisis , Asma/epidemiología , Infecciones Bacterianas/epidemiología , Dermatitis Atópica/epidemiología , Utilización de Medicamentos/estadística & datos numéricos , Exposición a Riesgos Ambientales/análisis , Efectos Tardíos de la Exposición Prenatal/epidemiología , Contaminantes Atmosféricos/análisis , Asma/terapia , Infecciones Bacterianas/terapia , Niño , Minas de Carbón , Dermatitis Atópica/terapia , Prescripciones de Medicamentos/estadística & datos numéricos , Femenino , Fuego , Humanos , Incidencia , Lactante , Masculino , Material Particulado/análisis , Embarazo , Efectos Tardíos de la Exposición Prenatal/terapia , Factores de Tiempo , Victoria/epidemiología
20.
Environ Pollut ; 256: 113381, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31662259

RESUMEN

Approximately 3 billion people world-wide are exposed to air pollution from biomass burning. Herein, particulate matter (PM) emitted from artisanal cashew nut roasting, an important economic activity worldwide, was investigated. This study focused on: i) chemical characterization of polycyclic aromatic hydrocarbons (PAHs) and oxygenated (oxy-) PAHs; ii) intracellular levels of reactive oxygen species (ROS); iii) genotoxic effects and time- and dose-dependent activation of DNA damage signaling, and iv) differential expression of genes involved in xenobiotic metabolism, inflammation, cell cycle arrest and DNA repair, using A549 lung cells. Among the PAHs, chrysene, benzo[a]pyrene (B[a]P), benzo[b]fluoranthene, and benz[a]anthracene showed the highest concentrations (7.8-10 ng/m3), while benzanthrone and 9,10-anthraquinone were the most abundant oxy-PAHs. Testing of PM extracts was based on B[a]P equivalent doses (B[a]Peq). IC50 values for viability were 5.7 and 3.0 nM B[a]Peq at 24 h and 48 h, respectively. At these low doses, we observed a time- and dose-dependent increase in intracellular levels of ROS, genotoxicity (DNA strand breaks) and DNA damage signaling (phosphorylation of the protein checkpoint kinase 1 - Chk1). In comparison, effects of B[a]P alone was observed at micromolar range. To our knowledge, no previous study has demonstrated an activation of pChk1, a biomarker used to estimate the carcinogenic potency of PAHs in vitro, in lung cells exposed to cashew nut roasting extracts. Sustained induction of expression of several important stress response mediators of xenobiotic metabolism (CYP1A1, CYP1B1), ROS and pro-inflammatory response (IL-8, TNF-α, IL-2, COX2), and DNA damage response (CDKN1A and DDB2) was also identified. In conclusion, our data show high potency of cashew nut roasting PM to induce cellular stress including genotoxicity, and more potently when compared to B[a]P alone. Our study provides new data that will help elucidate the toxic effects of low-levels of PAH mixtures from air PM generated by cashew nut roasting.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Anacardium/química , Daño del ADN , Nueces/química , Material Particulado/toxicidad , Hidrocarburos Policíclicos Aromáticos/toxicidad , Células A549 , Contaminantes Atmosféricos/análisis , Biomasa , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Relación Dosis-Respuesta a Droga , Humanos , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Transducción de Señal , Factores de Tiempo
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