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1.
Artigo em Inglês | MEDLINE | ID: mdl-32696403

RESUMO

The occurrence of local high-pollution episodes in densely populated urban areas, which have huge fleets of vehicles, is currently one of the most worrying problems associated with air pollution worldwide. Such episodes are produced under specific meteorological conditions, which favour the sudden increase of levels of air pollutants. This study has investigated the influence of the mixing layer height (MLH) on the concentration levels of atmospheric pollutants and daily mortality in Madrid, Spain, during the period 2011-2014. It may help to understand the causes and impact of local high-pollution episodes. MLH at midday over Madrid was daily estimated from meteorological radio soundings. Then, days with different MLH over this urban area were characterized by meteorological parameters registered at different levels of an instrumented tower and by composite sea level pressure maps, representing the associated synoptic meteorological scenarios. Next, statistically significant associations between MLH and levels of PM10, PM2.5, NO, NO2, CO and ultra-fine particles number concentrations registered at representative monitoring stations were evaluated. Finally, associations between all-natural cause daily mortality in Madrid, MLH, and air pollutants were estimated using conditional Poisson regression models. The reduction of MLH to values below 482 m above-ground level under strong atmospheric stagnation conditions was accompanied by a statistically significant increase in levels of NO, NO2, CO, PM2.5 and ultra-fine particle number concentrations at urban-traffic and suburban monitoring sites. The decrease of the MLH was also associated to a linear increase of the daily number of exceedances of the UE NO2 hourly limit value (200 µg/m3) and levels of air pollutants at hotspot urban-traffic monitoring stations. Also, a statistically significant association of the MLH with all-natural cause daily mortality was obtained. When the MLH increased by 830 m, the risk of mortality decreased by 2.5% the same day and by 3.3% the next day, when African dust episodic days were excluded. They were also higher in absolute terms than the increases in risk of mortality that were determined for the exposition to any other air pollutant. Our results suggest that when the prediction models foresee values of MLH below 482 m above-ground level in Madrid, the evolution of high-contamination episodes will be very favourable. Therefore, short-term policy measures will have to be implemented to reduce NO, NO2, CO, PM2.5 and ultra-fine particle emissions from anthropogenic sources in this southern European urban location.

2.
Chemosphere ; 248: 125896, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32006840

RESUMO

Biomass burning is a major air pollution problem all around the world. However, the identification and quantification of its contribution to ambient aerosol levels is a difficult task due to the generalized lack of observations of molecular markers. This paper presents the results of a yearlong study of organic constituents of the atmospheric aerosol at a rural site in southern Spain (Villanueva del Arzobispo, Jaén). Sampling was performed for PM10 and PM2.5, and a total of 116 and 115 samples, respectively, were collected and analyzed by GC/MS, quantifying 77 organic compounds. Higher levels of organic pollutants were recorded from November to March, coinciding with the cold season when domestic combustion is a common practice in rural areas. This jointly with adverse meteorological conditions, e.g. strong atmospheric stability, produced severe pollution episodes with high PMx ambient levels. High daily concentrations of tracers were reached, up to 26 ng m-3 for B(a)P and 6065 ng m-3 for levoglucosan in PM2.5, supporting that biomass burning is a major source of pollution at rural areas. A multivariate statistical study based on factor and cluster analysis, was applied to the data set with the aim to distinguish sources of organic compounds. The main resulting sources were related with biomass combustion, secondary organic aerosol (SOA), biogenic emissions, lubricating oil and soil organic components. A preliminary organic source profile for olive wastes burning was evaluated, based on cluster results, showing anhydrosacharides and xylitol are the main emitted compounds, accounting for more than 85% of the quantified compounds. Other source compounds were fatty acids, diacids, aliphatics, sugars, sugar alcohols, PAHs and quinones.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Incineração , Olea , Poluição do Ar/análise , Biomassa , Monitoramento Ambiental , Compostos Orgânicos/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Estações do Ano , Solo , Espanha
3.
Environ Sci Pollut Res Int ; 26(29): 30426-30443, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31440972

RESUMO

This study has assessed the influence of the origin of air mass on levels of particulate matter (PM10) and chemical composition (SO42- and NO3-) in the air basin of Madrid. A data set of back-trajectories of air mass arriving to this area of study from 15 June 15 2009 to 8 July 2011 has been analyzed. Firstly, the cluster analysis statistical method has been used to group the back-trajectories into 5 sets according to the angle, direction, and speed of the air mass. Afterwards, the synoptic meteorological scenarios associated with each cluster were obtained and interpreted. Subsequently, an analysis was made on the influence of these clusters on the surface levels of particulate pollutants recorded in a regional background station ("El Atazar"), as well as in two urban background stations ("Casa de Campo" and "CIEMAT"). Finally, potential source areas of PM10, SO42-, and NO3- that contributed to the increase in their background levels in the Madrid air basin were detected by analyzing residence times of trajectories. Transport of mineral desert dust is probably the main cause of the increase of regional and urban background levels of PM10 in the Madrid air basin. In the case of SO42-, relatively high levels were registered, associated with air mass coming from Southern Europe and the Mediterranean Sea. In these regions, strong emissions of SO42- are produced due to industrial combustion and maritime traffic. Otherwise, relatively high levels of NO3- were registered during meteorological situations defined by a low baric gradient in the Iberian Peninsula. This meteorological pattern favors the accumulation of emissions from local and regional sources. Besides, the main urban centers of northeastern Europe and industrial areas located in the north African coast were also identified as potential source areas of NO3-. The statistical analysis of the back-trajectories by different methods and the comparison of the results obtained with observational data confirmed that numerous industrial areas in Europe and North Africa, as well as natural ones, such as deserts, had an influence on the regional and urban background levels of mass and chemical composition of particulate matter in the Madrid air basin, under the development of specific synoptic meteorological situations. Graphical abstract.


Assuntos
Poluição do Ar/análise , Compostos Inorgânicos/análise , Material Particulado/análise , África do Norte , Poluentes Atmosféricos/análise , Atmosfera , Poeira/análise , Monitoramento Ambiental/métodos , Indústrias , Região do Mediterrâneo , Mar Mediterrâneo , Conceitos Meteorológicos , Espanha , Análise Espaço-Temporal
5.
Sci Total Environ ; 635: 1561-1573, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29605235

RESUMO

Exceedances of NO2 hourly limit value (200 µg·m-3) imply the need to implement short term action plans to avoid adverse effects on human health in urban areas. The Madrid City Council applied the stage 3 of the NO2 protocol during a high-pollution episode under stable meteorological conditions on December 2016 for the first time. This included road traffic access restrictions to the city centre (50% of conventional private vehicles based on plate numbers). In this contribution we analyse different meteorological and air quality observations, including non-standard parameters (such as number of ultrafine particles and remote sensing techniques MAXDOAS) for a better understanding of the effectivity of short-term emission abatement measures under real conditions and to identify options to improve the NO2 protocol in the future. According to our results, the inversion base height computed from vertical temperature soundings is a meaningful index to anticipate very unfavourable conditions and trigger the actions included in the protocol. The analysis of the concentration levels of the main pollutants from the Madrid air quality monitoring network indicate that only stage 3 of the protocol had a significant effect on NO2 maximum concentrations. The restrictions applied may have prevented NO2 concentrations to further increase in the city centre (up to 15%) although pollution levels in the city outskirts, outside the area directly affected by the traffic restrictions, remained unchanged or may have been slightly increased. Nonetheless, further studies are needed to estimate more precisely the effect of the measures taken and to assess potential trade-offs. Our results suggest that emissions play an important role also under very strong stability conditions although drastic measures are needed to achieve a significant impact. This highlights the importance of an appropriate timing for short-term actions and the need of permanent abatement measures related to air quality plans and policies.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Cidades , Material Particulado/análise , Espanha , Emissões de Veículos/análise
6.
Chemosphere ; 119: 769-777, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25194477

RESUMO

A detailed spatial and temporal assessment of urban NH3 levels and potential emission sources was made with passive samplers in six major Spanish cities (Barcelona, Madrid, A Coruña, Huelva, Santa Cruz de Tenerife and Valencia). Measurements were conducted during two different periods (winter-autumn and spring-summer) in each city. Barcelona showed the clearest spatial pattern, with the highest concentrations in the old city centre, an area characterised by a high population density and a dense urban architecture. The variability in NH3 concentrations did not follow a common seasonal pattern across the different cities. The relationship of urban NH3 with SO2 and NOX allowed concluding on the causes responsible for the variations in NH3 levels between measurement periods observed in Barcelona, Huelva and Madrid. However, the factors governing the variations in A Coruña, Valencia and Santa Cruz de Tenerife are still not fully understood. This study identified a broad variability in NH3 concentrations at the city-scale, and it confirms that NH3 sources in Spanish urban environments are vehicular traffic, biological sources (e.g. garbage containers), wastewater treatment plants, solid waste treatment plants and industry. The importance of NH3 monitoring in urban environments relies on its role as a precursor of secondary inorganic species and therefore PMX. Further research should be addressed in order to establish criteria to develop and implement mitigation strategies for cities, and to include urban NH3 sources in the emission inventories.


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Cidades , Monitoramento Ambiental , Estações do Ano , Espanha
7.
Environ Int ; 75: 151-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25461424

RESUMO

BACKGROUND: Few recent studies examined acute effects on health of individual chemical species in the particulate matter (PM) mixture, and most of them have been conducted in North America. Studies in Southern Europe are scarce. The aim of this study is to examine the relationship between particulate matter constituents and daily hospital admissions and mortality in five cities in Southern Europe. METHODS: The study included five cities in Southern Europe, three cities in Spain: Barcelona (2003-2010), Madrid (2007-2008) and Huelva (2003-2010); and two cities in Italy: Rome (2005-2007) and Bologna (2011-2013). A case-crossover design was used to link cardiovascular and respiratory hospital admissions and total, cardiovascular and respiratory mortality with a pre-defined list of 16 PM10 and PM2.5 constituents. Lags 0 to 2 were examined. City-specific results were combined by random-effects meta-analysis. RESULTS: Most of the elements studied, namely EC, SO4(2-), SiO2, Ca, Fe, Zn, Cu, Ti, Mn, V and Ni, showed increased percent changes in cardiovascular and/or respiratory hospitalizations, mainly at lags 0 and 1. The percent increase by one interquartile range (IQR) change ranged from 0.69% to 3.29%. After adjustment for total PM levels, only associations for Mn, Zn and Ni remained significant. For mortality, although positive associations were identified (Fe and Ti for total mortality; EC and Mg for cardiovascular mortality; and NO3(-) for respiratory mortality) the patterns were less clear. CONCLUSIONS: The associations found in this study reflect that several PM constituents, originating from different sources, may drive previously reported results between PM and hospital admissions in the Mediterranean area.


Assuntos
Poluentes Atmosféricos/análise , Doenças Cardiovasculares/mortalidade , Hospitalização/estatística & dados numéricos , Material Particulado/análise , Doenças Respiratórias/mortalidade , Doenças Cardiovasculares/epidemiologia , Cidades/epidemiologia , Humanos , Itália/epidemiologia , Metais Pesados/análise , Nitratos/análise , Tamanho da Partícula , Doenças Respiratórias/epidemiologia , Espanha/epidemiologia , Sulfatos/análise
8.
Environ Pollut ; 159(8-9): 2138-47, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21269745

RESUMO

Tropospheric ozone (O(3)) is considered one of the most important air pollutants affecting human health. The role of peri-urban vegetation in modifying O(3) concentrations has been analyzed in the Madrid region (Spain) using the V200603par-rc1 version of the CHIMERE air quality model. The 3.7 version of the MM5 meteorological model was used to provide meteorological input data to the CHIMERE. The emissions were derived from the EMEP database for 2003. Land use data and the stomatal conductance model included in CHIMERE were modified according to the latest information available for the study area. Two cases were considered for the period April-September 2003: (1) actual land use and (2) a fictitious scenario where El Pardo peri-urban forest was converted to bare-soil. The results show that El Pardo forest constitutes a sink of O(3) since removing this green area increased O(3) levels over the modified area and over down-wind surrounding areas.


Assuntos
Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Modelos Químicos , Árvores/fisiologia , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/metabolismo , Cidades , Ozônio/análise , Ozônio/metabolismo , Espanha , Árvores/classificação , Árvores/metabolismo
9.
Environ Sci Technol ; 44(23): 8814-20, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21049991

RESUMO

African dust (AD) contributions to particulate matter (PM) levels may be reported by Member States to the European Commission during justification of exceedances of the daily limit value (DLV). However, the detection and subsequent quantification of the AD contribution to PM levels is complex, and only two measurement-based methods are available in the literature: the Spanish-Portuguese reference method (SPR), and the Tel Aviv University method (TAU). In the present study, both methods were assessed. The SPR method was more conservative in the detection of episodes (71 days identified as AD by SPR, vs 81 by TAU), as it is less affected by interferences with local dust sources. The mean annual contribution of AD was lower with the TAU method than with SPR (2.7 vs 3.5 ± 1.5 µg/m(3)). The SPR and TAU AD time series were correlated with daily aluminum levels (a known tracer of AD), as well as with an AD source identified by the Positive Matrix Factorization (PMF) receptor model. Higher r(2) values were obtained with the SPR method than with TAU in both cases (r(2) = 0.72 vs 0.56, y = 0.05x vs y = 0.06x with aluminum levels; r(2)=0.79 vs 0.43, y = 0.8x vs y = 0.4x with the PMF source). We conclude that the SPR method is more adequate from an EU policy perspective (justification of DLV exceedances) due to the fact that it is more conservative than the TAU method. Based on our results, the TAU method requires adaptation of the thresholds in the algorithm to refine detection of low-impact episodes and avoid misclassification of local events as AD.


Assuntos
Poluentes Atmosféricos/análise , Poeira/análise , Monitoramento Ambiental/métodos , Poluição do Ar/legislação & jurisprudência , Poluição do Ar/estatística & dados numéricos , Política Ambiental , União Europeia , Tamanho da Partícula
10.
Anal Chem ; 81(11): 4382-8, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19425532

RESUMO

This work describes the first analytical method specifically developed for the multianalyte determination of several drugs of abuse and their metabolites in air. The methodology is based on pressurized liquid extraction (PLE) of atmospheric particles collected by means of high volume sampler equipped with quartz microfiber filters and subsequent analysis of the extracts by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Up to 17 different compounds belonging to five different chemical classes (cocainics, amphetamine-like compounds, opioids, cannabinoids, and lysergic compounds) are determined by means of this methodology. Acquisition is performed in the selected reaction monitoring (SRM) mode recording two transitions per compound (except for amphetamine). Quantitation by the internal standard method is based on the use of surrogated deuterated standards. The method has been validated in terms of linearity, accuracy, repeatability and sensitivity with satisfactory results. Absolute recoveries were above 50% for most investigated compounds. Method precision showed relative standard deviations (RSD) below 13% for all compounds, except for cannabinoids. The method limits of determination ranged from 0.35 pg/m(3) (for 2-oxo-3-hydroxy-LSD) to 22.55 pg/m(3) (for 11-nor-9 carboxy THC). Finally, as a part of the method validation, the optimized procedure was applied to the analysis of ambient air samples (fine grain-size particulates, PM(2.5)) collected at two urban background sites in Barcelona and Madrid (Spain). Results evidenced the presence of cocaine, benzoilecgonine, tetrahydrocannabinol, ecstasy, amphetamine, methamphetamine, and heroin in some or all of the samples investigated. The highest mean daily levels corresponded to cocaine (850 pg/m(3)) followed by heroin (143 pg/m(3)).


Assuntos
Ar/análise , Cromatografia Líquida/métodos , Material Particulado/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espanha
11.
Sci Total Environ ; 390(2-3): 495-506, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18045660

RESUMO

This study has investigated the influence of synoptic weather patterns and long-range transport episodes on the concentration levels of airborne particulate matter (TSP, PM10 and PM2.5) and some major ions (SO(4)(2-), NO(3)(-) and NH(4)(+)) at a background rural station in central Spain. Air mass back-trajectories arriving at the site in 1999-2005 have been analysed by statistical methods. First, cluster analysis was used to group trajectories into 8 clusters depending on their direction and speed. Meteorological scenarios associated to each cluster have been obtained and interpreted. Then, the incidence of different air mass transport patterns on particle concentrations and composition recorded at this station was evaluated. This evaluation included PM10 and PM2.5 concentrations and chemical composition data, obtained at three representative sites of the Madrid air basin during sampling campaigns carried out in the course of the 1999-2005 period. Finally, a residence time analysis of trajectories was also performed to detect remote sources and transport pathways. Significantly elevated concentrations of TSP and PM10 were observed for Northern African flows as a consequence of the transport of mineral dust. Significant inter-cluster differences were also observed for PM2.5 and secondary inorganic compounds, with the highest concentrations associated with low baric gradient situations and Southern European flows. The residence time analysis confirmed that current TSP and PM10 concentrations in central Spain are likely to be influenced significantly by long-range transport of desert dust from different desert regions in North Africa. Furthermore, emissions from continental Europe with a high time of residence in the western and central areas of the Mediterranean basin, seem to significantly influence PM2.5 and secondary inorganic aerosol concentrations in this region.


Assuntos
Movimentos do Ar , Tamanho da Partícula , Material Particulado/química , Cidades , Análise por Conglomerados , Interpretação Estatística de Dados , Espanha
12.
J Environ Monit ; 8(10): 1060-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17240912

RESUMO

Source apportionment study was performed, applying principal component analysis to the results of 221 chemical analyses of PM10 and PM2.5 samples collected daily from the industrial (but low traffic) Spanish town of Puertollano over a 14-month period during 2004-2005. Results reveal compositional variations attributable to different mixtures of natural and anthropogenic materials, mainly soil and rock dust (crustal), marine salt (only in PM10), petrochemical refinery emissions, and particles attributed to the combustion of local coal, which is unusually rich in Pb and Sb. During the study period there were 34 pollution episodes when PM10 exceeded 50 tg m(-3), mostly due to winter air temperature inversions, regional atmospheric stagnation, or African dust incursions (North African, NAF days: usually in summer). Whereas the crustal component during NAF episodes averaged 52% with a PM2.5/PM10 ratio of 0.54, this dropped to 29% and a PM2.5/PM10 of 0.67 during non-NAF days when anthropogenic materials predominated. Abnormally enhanced concentrations of pathfinder metallic trace elements provide additional evidence for source apportionment: thus aerosols with raised levels of Pb and Sb are associated with local coal combustion, Ni and V can be linked to petrochemical PM emissions, and Ti, Mn, Rb, and Ce are particularly characteristic of crustal dust incursions.


Assuntos
Poluentes Atmosféricos/análise , Metais/análise , Material Particulado/análise , Aerossóis , Poluição do Ar/análise , Indústria Química , Carvão Mineral , Monitoramento Ambiental , Tamanho da Partícula , Petróleo , Centrais Elétricas , Espanha
13.
Environ Pollut ; 125(3): 453-65, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12826423

RESUMO

Non-mineral carbon is the main component of PM10 and PM2.5 at an urban roadside site in Madrid accounting for more than 50% of the total bulk mass in winter pollution episodes. In these cases a 70-80% of the particle mass is anthropogenic. Particles of crustal/mineral origin contribute significantly to the observed PM10 concentrations, especially in spring and summer. They have also been found in the PM2.5 fraction although secondary particles are the next most important contributor in this size. Long-range transport particle episodes of Saharan dust significantly contribute to exceedence of the new daily limiting PM10 value in the urban network and at nearby rural background stations. This type of long-range transport event also influences PM2.5 concentrations. The crustal contribution can account for up to 67 and 53% of the PM10 and PM2.5 bulk mass in such cases.


Assuntos
Poluentes Atmosféricos/análise , Saúde da População Urbana , Aerossóis/análise , Aerossóis/química , Poluentes Atmosféricos/química , Carbono/análise , Fenômenos Químicos , Físico-Química , Poeira/análise , Monitoramento Ambiental/métodos , Humanos , Tamanho da Partícula , Estações do Ano , Espanha , Emissões de Veículos/análise
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