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1.
ACS Omega ; 7(17): 14697-14711, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35557669

RESUMEN

This paper reports on the chemical speciation and leaching behavior of a selected group of hazardous trace pollutants in lignite and lignite-petcoke blend co-combustion products from three power stations in China. The evaluation of speciation results showed that, during combustion, oxidizable elements, mainly As and Mo, bound to organic matter and sulfides in coals were mostly transferred to easily water-soluble forms or to slightly acidic states in the ashes. This manner was the most readily bioavailable condition for such an environment. The evaluation of the leaching results shows that the use of petroleum coke as co-fuel has an impact on the ash composition and on the leaching behavior of some inorganic trace pollutants such as Mo and V. The leaching results compared to the European waste acceptance criteria for landfills reveal that the Mo and As' leaching yield brand the coal combustion products as materials that necessitate preventative measures to reduce their potential leaching. Future work will be focused on the application of our novel chemical stabilization method to these coal ashes to reduce the mobility of elements such as Mo and As, and other potentially leachable elements, and on the use of the resulting ash with aggregate products as a substitute for concrete production.

4.
Environ Sci Pollut Res Int ; 29(24): 36255-36272, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35060032

RESUMEN

PM10 was collected during an EMEP winter campaign of 2017-2018 in two urban background sites in Barcelona (BCN) and Granada (GRA), two Mediterranean cities in the coast and inland, respectively. The concentrations of PM10, organic carbon (OC), elemental carbon (EC), and organic molecular tracer compounds such as hopanes, anhydro-saccharides, polycyclic aromatic hydrocarbon, and several biogenic and anthropogenic markers of secondary organic aerosols (SOA) were two times higher in GRA compared to BCN and related to the atmospheric mixing heights in the areas. Multivariate curve resolution (MCR-ALS) source apportionment analysis identified primary emissions sources (traffic + biomass burning) that were responsible for the 50% and 20% of the organic aerosol contributions in Granada and Barcelona, respectively. The contribution of biomass burning was higher in the holidays than in the working days in GRA while all primary combustion emissions decreased in holidays in BCN. The MCR-ALS identified that oxidative species and SOA formation processes contributed to 40% and 80% in Granada and Barcelona, respectively. Aged SOA was dominant in Granada and Barcelona under stagnant atmospheric conditions and in presence of air pollution. On the other hand, fresh SOA contributions from α-pinene oxidation (cis-pinonic acid) were three times higher in Barcelona than Granada and could be related to new particle formation, essentially due to overall cleaner air conditions and elevated air temperatures.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Ciudades , Monitoreo del Ambiente , Compuestos Orgánicos/análisis , Material Particulado/análisis , Estaciones del Año
5.
Environ Res ; 205: 112451, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34848209

RESUMEN

Measurements of CO2 and counting of occupants were carried out in 37 public bus trips during commuting rush hours in Barcelona (NE Spain) with the aim of evaluating parameters governing ventilation inside the vehicles and proposing actions to improve it. The results show that CO2 concentrations (1039 and 934 ± 386 ppm, as average and median, during rush hours but with average reduced occupancy due to the fair to be infected by SARS-CoV-2 during the measurement period, and measured in the middle of the busses) are in the lower range of values recorded in the literature for public buses, however an improvement in ventilation is required in a significant proportion of the journeys. Thus, we found better ventilation in the older Euro 3+ (retrofitted with filter traps and selective catalytic reduction) and Euro 5 buses (average 918 ± 257 ppm) than in the hermetically closed new Euro 6 ones (1111 ± 432 ppm). The opening of the windows in the older buses yielded higher ventilation rates (778 ± 432 ppm). The opening of all doors at all stops increases the ventilation by causing a fall in concentrations of 200-350 ppm below inter-stop concentrations, with this effect typically lasting 40-50 s in the hermetically closed new Euro 6 hybrid buses. Based on these results a number of recommendations are offered in order to improve ventilation, including measurement of CO2 and occupancy, and installation of ventilation fans on the top of the hermetically closed new buses, introducing outdoor air when a given concentration threshold is exceeded. In these cases, a CO2 sensor installed in the outdoor air intake is also recommended to take into account external CO2 contributions.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Contaminación del Aire Interior/análisis , Dióxido de Carbono/análisis , Humanos , Vehículos a Motor , SARS-CoV-2 , Transportes , Ventilación
6.
Sci Total Environ ; 800: 149486, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34391157

RESUMEN

This study evaluates geochemical and oxidative potential (OP) properties of the respirable (finer than 4 µm) fractions of 22 powdered coal samples from channel profiles (CP4) in Chinese mined coals. The CP4 fractions extracted from milled samples of 22 different coals were mineralogically and geochemically analysed and the relationships with the OP evaluated. The evaluation between CP4/CP demonstrated that CP4 increased concentrations of anatase, Cs, W, Zn and Zr, whereas sulphates, Fe, S, Mo, Mn, Hf and Ge decreased their CP4 concentrations. OP results from ascorbic acid (AA), glutathione (GSH) and dithiothreitol (DTT) tests evidenced a clear link between specific inorganic components of CP4 with OPAA and the organic fraction of OPGSH and OPDTT. Correlation analyses were performed for OP indicators and the geochemical patterns of CP4. These were compared with respirable dust samples from prior studies. They indicate that Fe (r = 0.83), pyrite (r = 0.66) and sulphate minerals (r = 0.42) (tracing acidic species from pyrite oxidation), followed by S (r = 0.50) and ash yield (r = 0.46), and, to a much lesser extent, Ti, anatase, U, Mo, V and Pb, are clearly linked with OPAA. Moreover, OPGSH correlation was identified by organic matter, as moisture (r = 0.73), Na (r = 0.56) and B (r = 0.51), and to a lesser extent by the coarse particle size, Ca and carbonate minerals. In addition, Mg (r = 0.70), B (r = 0.47), Na (r = 0.59), Mn, Ba, quartz, particle size and Sr regulate OPDTT correlations. These became more noticeable when the analysis was done for samples of the same type of coal rank, in this case, bituminous.


Asunto(s)
Carbón Mineral , Polvo , China , Carbón Mineral/análisis , Polvo/análisis , Estrés Oxidativo , Polvos
7.
Environ Int ; 157: 106818, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34425482

RESUMEN

This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015-2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O3 and the total gaseous oxidant (OX = NO2 + O3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015-2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO2 and NOx concentrations and peoples' mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO2 and between 30% and 40% in mean PM2.5 concentrations over 2020 full lockdown compared to the same period in 2015-2019. However, PM2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO2/CO ratio). Some Chinese cities showed similar increases in PM2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of ~70%. The SO2 anomalies were negative for 2020 compared to 2015-2019 (between ~25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to ~40%. The NO2/CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO2 decrease due to the general reduction in mobility (ratio of ~60%). Analysis of the total oxidant (OX = NO2 + O3) showed that primary NO2 emissions at urban locations were greater than the O3 production, whereas at background sites, OX was mostly driven by the regional contributions rather than local NO2 and O3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Pandemias , Material Particulado/análisis , SARS-CoV-2
8.
Sci Total Environ ; 795: 148728, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34328931

RESUMEN

In this work, time-series analyses of the chemical composition and source contributions of PM2.5 from an urban background station in Barcelona (BCN) and a rural background station in Montseny (MSY) in northeastern Spain from 2009 to 2018 were investigated and compared. A multisite positive matrix factorization analysis was used to compare the source contributions between the two stations, while the trends for both the chemical species and source contributions were studied using the Theil-Sen trend estimator. Between 2009 and 2018, both stations showed a statistically significant decrease in PM2.5 concentrations, which was driven by the downward trends of levels of chemical species and anthropogenic source contributions, mainly from heavy oil combustion, mixed combustion, industry, and secondary sulfate. These source contributions showed a continuous decrease over the study period, signifying the continuing success of mitigation strategies, although the trends of heavy oil combustion and secondary sulfate have flattened since 2016. Secondary nitrate also followed a significant decreasing trend in BCN, while secondary organic aerosols (SOA) very slightly decreased in MSY. The observed decreasing trends, in combination with the absence of a trend for the organic aerosols (OA) at both stations, resulted in an increase in the relative proportion of OA in PM2.5 by 12% in BCN and 9% in MSY, mostly from SOA, which increased by 7% in BCN and 4% in MSY. Thus, at the end of the study period, OA accounted for 40% and 50% of the annual mean PM2.5 at BCN and MSY, respectively. This might have relevant implications for air quality policies aiming at abating PM2.5 in the study region and for possible changes in toxicity of PM2.5 due to marked changes in composition and source apportionment.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Nitratos , Material Particulado/análisis , España , Emisiones de Vehículos/análisis
9.
Environ Int ; 156: 106732, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34197974

RESUMEN

Severe episodic air pollution blankets entire cities and regions and have a profound impact on humans and their activities. We compiled daily fine particle (PM2.5) data from 100 cities in five continents, investigated the trends of number, frequency, and duration of pollution episodes, and compared these with the baseline trend in air pollution. We showed that the factors contributing to these events are complex; however, long-term measures to abate emissions from all anthropogenic sources at all times is also the most efficient way to reduce the occurrence of severe air pollution events. In the short term, accurate forecasting systems of such events based on the meteorological conditions favouring their occurrence, together with effective emergency mitigation of anthropogenic sources, may lessen their magnitude and/or duration. However, there is no clear way of preventing events caused by natural sources affected by climate change, such as wildfires and desert dust outbreaks.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Monitoreo del Ambiente , Humanos , Meteorología , Material Particulado/análisis
10.
Environ Int ; 155: 106662, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34098335

RESUMEN

BACKGROUND: The evidence on the association between ultrafine (UFP) particles and mortality is still inconsistent. Moreover, health effects of specific UFP sources have not been explored. We assessed the impact of UFP sources on daily mortality in Barcelona, Helsinki, London, and Zurich. METHODS: UFP sources were previously identified and quantified for the four cities: daily contributions of photonucleation, two traffic sources (fresh traffic and urban, with size mode around 30 nm and 70 nm, respectively), and secondary aerosols were obtained from data from an urban background station. Different periods were investigated in each city: Barcelona 2013-2016, Helsinki 2009-2016, London 2010-2016, and Zurich 2011-2014. The associations between total particle number concentrations (PNC) and UFP sources and daily (natural, cardiovascular [CVD], and respiratory) mortality were investigated using city-specific generalized linear models (GLM) with quasi-Poisson regression. RESULTS: We found inconsistent results across cities, sources, and lags for associations with natural, CVD, and respiratory mortality. Increased risk was observed for total PNC and natural mortality in Helsinki (lag 2; 1.3% [0.07%, 2.5%]), CVD mortality in Barcelona (lag 1; 3.7% [0.17%, 7.4%]) and Zurich (lag 0; 3.8% [0.31%, 7.4%]), and respiratory mortality in London (lag 3; 2.6% [0.84%, 4.45%]) and Zurich (lag 1; 9.4% [1.0%, 17.9%]). A similar pattern of associations between health outcomes and total PNC was followed by the fresh traffic source, for which we also found the same associations and lags as for total PNC. The urban source (mostly aged traffic) was associated with respiratory mortality in Zurich (lag 1; 12.5% [1.7%, 24.2%]) and London (lag 3; 2.4% [0.90%, 4.0%]) while the secondary source was associated with respiratory mortality in Zurich (lag 1: 12.0% [0.63%, 24.5%]) and Helsinki (4.7% [0.11%, 9.5%]). Reduced risk for the photonucleation source was observed for respiratory mortality in Barcelona (lag 2, -8.6% [-14.5%, -2.4%]) and for CVD mortality in Helsinki, as this source is present only in clean atmospheres (lag 1, -1.48 [-2.75, -0.21]). CONCLUSIONS: We found inconsistent results across cities, sources and lags for associations with natural, CVD, and respiratory mortality.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Anciano , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/análisis , Ciudades , Humanos , Tamaño de la Partícula , Material Particulado/análisis
11.
J Environ Health Sci Eng ; 19(1): 907-916, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34150281

RESUMEN

PURPOSE: The aim of the present study was to investigate the effect of short-term exposure to ambient black carbon (BC) on daily cause-specific mortality, including mortality due to respiratory, cardiovascular, ischemic heart and cerebrovascular diseases in Tehran, Iran. MATERIALS AND METHODS: Daily non-accidental death counts, meteorological data and hourly concentrations of air pollutants from 2014 to 2017 were collected in Tehran. A distributed lag non-linear model was used to assess the association between exposure to BC and daily mortality. RESULTS: The mean daily BC concentration during the study period was 3.96 ± 1.19 µg/m3. The results indicated that BC was significantly associated with cardiovascular, ischemic heart disease, and cerebrovascular mortality, but not with respiratory mortality. In first model, each 10 µg/m3 increase in at lag 3, lag 4 and lag 5 were associated with cardiovascular mortality in 16-65 year age group with the relative risks (RRs) of 1.17 (95 % CI: 1.02-1.33), 1.17 (95 % CI: 1.04-1.31) and 1.12 (95 % CI: 1.02-1.24), respectively. The highest mortality rate per 10 µg/m3 increase in exposure was found for ischemic heart diseases with RR of 3.98 (95 % CI: 1.04-1.81, lag 01) for 16-65 age group. Cerebrovascular mortality was associated with 10 µg/m3 increases in non-cumulative exposure with RR of 1.17 (95 % 1.009-1.35, lag 5) in the age group ≥ 65 years. In the second model for a 10 µg/m3 increase in BC, cardiovascular mortality at specific lag days (5 and 6 days) in the age group ≤ 16 years were associated with RR of 1.34 (95 % CI 1.08-1.66) and 1.35(95 % CI 1.02-1.77), respectively. CONCLUSIONS: This study in Tehran found significant effects of BC exposure on daily mortality for cardiovascular, ischemic heart disease, cerebrovascular disease. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40201-021-00659-0.

12.
Sci Total Environ ; 779: 146380, 2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34030280

RESUMEN

We offer an overview of the COVID-19 -driven air quality changes across 11 metropolises in Spain with the focus on lessons learned on how continuing abating pollution. Traffic flow decreased by up to 80% during the lockdown and remained relatively low during the full relaxation (June and July). After the lockdown a significant shift from public transport to private vehicles (+21% in Barcelona) persisted due to the pervasive fear that using public transport might increase the risk of SARS-CoV-2 infection, which need to be reverted as soon as possible. NO2 levels fell below 50% of the WHO annual air quality guidelines (WHOAQGs), but those of PM2.5 were reduced less than expected due to the lower contributions from traffic, increased contributions from agricultural and domestic biomass burning, or meteorological conditions favoring high secondary aerosol formation yields. Even during the lockdown, the annual PM2.5 WHOAQG was exceeded in cities within the NE and E regions with high NH3 emissions from farming and agriculture. Decreases in PM10 levels were greater than in PM2.5 due to reduced emissions from road dust, vehicle wear, and construction/demolition. Averaged O3 daily maximum 8-h (8hDM) experienced a generalized decrease in the rural receptor sites in the relaxation (June-July) with -20% reduced mobility. For urban areas O3 8hDM responses were heterogeneous, with increases or decreases depending on the period and location. Thus, after canceling out the effect of meteorology, 5 out of 11 cities experienced O3 decreases during the lockdown, while the remaining 6 either did not experience relevant reductions or increased. During the relaxation period and coinciding with the growing O3 season (June-July), most cities experienced decreases. However, the O3 WHOAQG was still exceeded during the lockdown and full relaxation periods in several cities. For secondary pollutants, such as O3 and PM2.5, further chemical and dispersion modeling along with source apportionment techniques to identify major precursor reduction targets are required to evaluate their abatement potential.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , SARS-CoV-2 , España
14.
Environ Int ; 156: 106614, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34000503

RESUMEN

BACKGROUND: The recent evidence of the short-term impact of air pollution on youth cognitive functions is based primarily on observational studies. OBJECTIVES: We conducted a randomized controlled trial to assess whether purifying the air of the classrooms produced short-term changes in attention processes of adolescents. METHODS: We recruited a total of 2,123 adolescents (13-16 years old) in 33 high schools in Barcelona metropolitan area (Spain). In each school, adolescents from each class were randomly split into two equal-sized groups and assigned to two different classrooms. A set of two air cleaner devices with the same appearance (one recirculating and filtrating the air and the other only recirculating the air) was used. Each one of the devices was placed at random at one of the two classrooms. Students were masked to intervention allocation and had to complete several computerized activities for 1.5 h, including an attention test (Flanker task) to be performed at baseline and at the end of the intervention. The response speed consistency, expressed as hit reaction time standard error (HRT-SE, in ms), was measured as the primary outcome. Analyses were conducted using conditional linear regressions with classroom as strata, adjusted for variables that may differ from one class to another such as temperature, humidity and carbon dioxide concentration. RESULTS: Average levels of PM2.5 and black carbon throughout the 1.5 h of experiment were 89% and 87%, respectively, lower in the classrooms with air cleaner than in the control classrooms. No differences were found in the median of HRT-SE between classrooms with cleaned air and normal air (percent change: 1.37%, 95% confidence interval: -2.81%, 5.56%). Sensitivity analyses with secondary attention outcomes resulted in similar findings. CONCLUSIONS: Cleaning the air of a classroom to reduce exposure to air pollutants for 1.5 h did not have an impact on the attention function of adolescents. Still, in light of previous evidence suggesting an association between air pollution and attention, further experimental studies should explore other short-term timescales of exposure and age ranges.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Adolescente , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Atención , Humanos , Material Particulado/análisis , Instituciones Académicas , España
15.
Air Qual Atmos Health ; 14(7): 1071-1079, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33841587

RESUMEN

The preventive and cautionary measures taken by the UAE and Abu Dhabi governments to reduce the spread of the coronavirus disease (COVID-19) and promote social distancing have led to a reduction of mobility and a modification of economic and social activities. This paper provides statistical analysis of the air quality data monitored by the Environment Agency - Abu Dhabi (EAD) during the first 10 months of 2020, comparing the different stages of the preventive measures. Ground monitoring data is compared with satellite images and mobility indicators. The study shows a drastic decrease during lockdown in the concentration of the gaseous pollutants analysed (NO2, SO2, CO, and C6H6) that aligns with the results reported in other international cities and metropolitan areas. However, particulate matter (PM10 and PM2.5) averaged concentrations followed a markedly different trend from the gaseous pollutants, indicating a larger influence from natural events (sand and dust storms) and other anthropogenic sources. The ozone (O3) levels increased during the lockdown, showing the complexity of O3 formation. The end of lockdown led to an increase of the mobility and the air pollution; however, air pollutant concentrations remained in lower levels than during the same period of 2019. The results in this study show the large impact of human activities on the quality of air and present an opportunity for policymakers and decision-makers to design stimulus packages to overcome the economic slow-down, with strategies to accelerate the transition to resilient, low-emission economies and societies more connected to the nature that protect human health and the environment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11869-021-01000-2.

16.
Sci Total Environ ; 781: 146739, 2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-33798874

RESUMEN

Biomass burning (BB) including forest, bush, prescribed fires, agricultural fires, residential wood combustion, and power generation has long been known to affect climate, air quality and human health. With this work we supply a systematic review on the health effects of BB emissions in the framework of the WHO activities on air pollution. We performed a literature search of online databases (PubMed, ISI, and Scopus) from year 1980 up to 2020. A total of 81 papers were considered as relevant for mortality and morbidity effects. High risk of bias was related with poor estimation of BB exposure and lack of adjustment for important confounders. PM10 and PM2.5 concentrations originating from BB were associated with all-cause mortality: the meta-analytical estimate was equal to 1.31% (95% CI 0.71, 1.71) and 1.92% (95% CI -1.19, 5.03) increased mortality per each 10 µg m-3 increase of PM10 and PM2.5, respectively. Regarding cardiovascular mortality 8 studies reported quantitative estimates. For smoky days and for each 10 µg m-3 increase in PM2.5 concentrations, the risk of cardiovascular mortality increased by 4.45% (95% CI 0.96, 7.95) and by 3.30% (95% CI -1.97, 8.57), respectively. Fourteen studies evaluated whether respiratory morbidity was adversely related to PM2.5 (9 studies) or PM10 (5 studies) originating from BB. All found positive associations. The pooled effect estimates were 4.10% (95% CI 2.86, 5.34) and 4.83% (95% CI 0.06, 9.60) increased risk of total respiratory admissions/emergency visits, per 10 µg m-3 increases in PM2.5 and PM10, respectively. Regarding cardiovascular morbidity, sixteen studies evaluated whether this was adversely related to PM2.5 (10 studies) or PM10 (6 studies) originating from BB. They found both positive and negative results, with summary estimates equal to 3.68% (95% CI -1.73, 9.09) and 0.93% (95% CI -0.18, 2.05) increased risk of total cardiovascular admissions/emergency visits, per 10 µg m-3 increases in PM2.5 and PM10, respectively. To conclude, a significant number of studies indicate that BB exposure is associated with all-cause and cardiovascular mortality and respiratory morbidity.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Biomasa , Exposición a Riesgos Ambientales/análisis , Humanos , Material Particulado/efectos adversos , Material Particulado/análisis , Humo
17.
Environ Pollut ; 274: 116268, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33545528

RESUMEN

Air pollution coming from industrial activities is a matter of interest since their emissions can seriously affect to the human health of nearby populations. A more detailed study about industrial emissions is required in order to discriminate different activities contributing to pollutant sources. In this sense, gaseous pollutants (NO2, SO2 and O3) and PM10 levels has been studied in a complex industrial area in the southwest of Spain (La Rabida and the nearby city of Huelva) during the period 1996-2017. Hourly, daily, monthly and annual variations of PM10 and gaseous pollutants concentrations point to the industrial activity as the main SO2 source. Furthermore, traffic and resuspension emissions contribute to the NO2 and PM10 levels, respectively. Results from chemical composition of PM10 at both sites during the period 2015-2017 are characterized by high concentrations of the crustal components derived from natural and local resuspension. Arsenic is found to be the main geochemical anomaly at La Rabida (annual mean of 7 ng m-3), exceeding the European annual target of 6 ng m-3, which supposes a risk for the nearby population. An emission source from Cu-smelter has been identified in La Rabida and Huelva. A second source corresponding to emissions from polymetallic sulfides handling in a port area has been described for the first time in La Rabida. In addition, arsenic speciation results have identified three different As impacts scenarios as a function of the dominant wind direction, the SO2 episodes and the As extraction efficiency: impact of the Cu-smelter, impact of the bulk polymetallic sulfides and a mixed impact of both sources.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Arsénico , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Ciudades , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , España
18.
Ecotoxicol Environ Saf ; 208: 111488, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33120274

RESUMEN

Reducing the potential leaching of Mo and Ni from the fly ash (FA) of petroleum coke is an increasingly important issue as Asia and Europe's demand is expected to drastically intensify as continuing urbanisation and technological innovation demands ever more electricity. In the present study, we investigated coal combustion products (CCP) from a large coal-fired power station fed with a 56:44 coal/petroleum coke blend. Results revealed that leachable concentrations of Mo and Ni from FA were in the upper non-hazardous limit and in the inert limit, respectively (2003/33/EC). Whilst common prevention measures for Mo and Ni based on the adsorption capacity of boiler slag (BS), a mixture of BS: goethite, and jarosite, were considered insufficient to reduce the potential leaching of Mo into FA leachates, a novel chemical stabilisation method based on an aggregate product of portlandite and FA immobilised both Mo and Ni such that the resulting concentrations were below the limits established in the abovementioned 2003 EC Decision. Precipitation may be responsible for the fixation of Mo and Ni in the FA: portlandite aggregates as Ca(MoO4) and NiMoO4, respectively. The findings of this novel study support the use of this aggregate to reduce FA pollutants, which will be of particular interest to nations that remain largely coal/petroleum coke-dependant.


Asunto(s)
Ceniza del Carbón/análisis , Coque/análisis , Contaminantes Ambientales/análisis , Contaminación Ambiental/prevención & control , Molibdeno/química , Níquel/química , Contaminación Ambiental/análisis
19.
Environ Int ; 147: 106326, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33340987

RESUMEN

Given the widespread concern but general lack of information over the possibility of SARS-CoV-2 infection in public transport, key issues such as passenger personal hygiene, efficient air circulation systems, and the effective disinfection of frequently touched surfaces need to be evaluated to educate the public and diminish the risk of viral transmission as we learn to live with the ongoing pandemic. In this context we report on a study involving the collection of 99 samples taken from inside Barcelona buses and subway trains in May to July 2020. From this sample group 82 (58 surface swabs, 9 air conditioning (a/c) filters, 3 a/c dust, 12 ambient air) were selected to be analysed by RT-PCR for traces of the SARS-CoV-2 virus. Thirty of these selected samples showed evidence for one or more of 3 target RNA gene regions specific for this virus (IP2, IP4, E). Most (24) of these 30 samples showed positivity for only 1 of the 3 RNA targets, 4 samples yielded 2 targets, and 2 samples provided evidence for all 3 targets. RNA remnants were more common in surface swabs from support bars (23 out of 58) than in ambient air inside the vehicles (3 out of 12), with relatively higher concentrations of viral RNA fragments in buses rather than in trains. Whereas subway train a/c filters examined were all virus-free, 4 of the 9 bus a/c filter/dust samples yielded evidence for viral RNA. After nocturnal maintenance and cleaning most buses initially yielding positive results subsequently showed elimination of the RT-PCR signal, although signs of viral RNA remained in 4 of 13 initially positive samples. The presence of such remnant viral traces however does not demonstrate infectivity, which in the present study is considered unlikely given the fragmentary nature of the gene targets detected. Nevertheless, best practice demands that close attention to ventilation systems and regular vehicle disinfection in public transport worldwide need to be rigorously applied to be effective at eliminating traces of the virus throughout the vehicle, especially at times when COVID-19 cases are peaking. Additionally, infectivity tests should be implemented to evaluate the efficiency of disinfection procedures to complement the information resulting from RT-PCR analysis. Modelling the probability of infection whilst travelling in buses under different scenarios indicates that forced ventilation greatly reduces the risk.


Asunto(s)
COVID-19 , Vías Férreas , Humanos , Vehículos a Motor , Pandemias , ARN Viral , SARS-CoV-2
20.
Sci Total Environ ; 747: 141187, 2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-32799019

RESUMEN

Wet and dry aerosol deposition samples were collected from September 2010 to August 2012 at a remote background site in the Mallorca Isle (Western Mediterranean). Ions and major and trace elements were determined in soluble and insoluble fractions. Temporal variations of chemical components are discussed and interpreted. The overall pattern associated to long-range-transport air masses is studied: Dry/Wet deposition ratios, charges and composition depend clearly on the meteorological scenario. E.g. Dry/Wet ratio is 1:1 when air comes from North Africa, in contrast to a 1:9 ratio under the mainland Europe influence. Moreover, an innovating source apportionment study was conducted integrating both dry and wet deposition samples. Six sources were revealed, including marine aerosols (32%); two different mineral factors, African dust (15%) and regional dust (12%); two anthropogenic factors, one related to road traffic (8%) and another to regional sources (17%); and a mixed factor having biomass burning emissions and others sources (17%). Temporal variations and influence from long-range-transport air masses are also investigated. Fertilization deposition trends have also been explored, observing nutrients settling, as well as nitrate and sulphate, due to their agricultural interest. An important peak during January-February 2012 is studied in depth. Having in mind the strong impact of African dust on the global deposition budget, the analysis of elemental ratios between key dust components was investigated in order to identify major source areas affecting Western Mediterranean: Western Sahara, Algeria-Hoggar Massif and Tunisia-Libya. Differences among these regions are evident. E.g. the impact of industrial emissions is well-detected under outbreaks from Tunisia-Libya, with relatively high content of Ni and Pb.

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