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Abstract  

In 2006, elementary schools of inner-city Lisbon, Portugal were given questionnaires to identify respiratory problems. In 1,175 children aged 5–10 years, 27.7% reported rhinitis, 2.5% reported hay fever and 25.9% reported asthma symptoms. April and August were the months with higher incidence of rhinitis, with a considerable difference nonetheless (10.5% and 2.3%, respectively.). The former trends are addressed here by using meteorological data, PM2.5, and its elemental speciation. Mann-Whitney U-tests were applied to the data sets. Significantly higher values were found for humidity, K+, NH4 +, Sb and Zn in April, and for temperature, Cl, Mg2+ and Na+ in August. Commuter and heavy-duty traffic may contribute to rhinitis episodes.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Almeida, M. Freitas, C. Repolho, I. Dionísio, H. Dung, A. Caseiro, C. Alves, C. Pio, and A. Pacheco

Abstract  

The goal of this research is to determine trends and sources of airborne particulates in the centre of Lisbon, by using speciated particulate-matter data and back-trajectory analyses. Results showed that, in 2007, the annual PM2.5 concentration exceeded the World Health Organization recommended levels. PM2.5 diurnal variability and the ratio between weekdays’ and weekends’ concentrations indicated that traffic contributed highly to decreasing air quality. Air back-trajectory analysis showed that maritime air mass transport had a significant role on air quality in Lisbon, promoting the decrease of anthropogenic aerosol concentrations.

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Abstract  

The number of children reporting rhinitis by month is compared with air pollutant concentrations in Lisbon, where they live and attend school. INAA, ionic exchange chromatography and data accessed through the internet were statistically processed with the children rhinitis data. Association between rhinitis and atmospheric variables are processed using Spearman non-parametric statistics and principal component analysis. It is pointed out that traffic, soil resuspension from traffic, meteorological conditions, and industry air pollutants contribute to respiratory trends. Ir (Pt group), a vehicle catalyst, may have some contribution.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Almeida, M. Freitas, C. Repolho, I. Dionísio, H. Dung, C. Pio, C. Alves, A. Caseiro, and A. Pacheco

Abstract  

Recent health studies evidence that epidemiological studies must be combined with accurate analyses of the physico-chemical properties of the particles in order to determine the effects of atmospheric aerosols on human health. The project “Atmospheric Aerosol Impacts on Human Health” focuses on the chemical characterization of PM2.5 aerosols with the aim to analyze the health risks associated with exposure to aerosols and understand how their chemical composition contributes to the toxicity and human health problems traditionally associated with fine particles. During one year, PM2.5 was collected daily, with a Partisol sampler, in the centre of Lisbon. The aerosols were analyzed by Neutron Activation Analysis and Ion Chromatography in order to determine their chemical composition. In parallel the clinical situation of students from the schools situated around the sampler was followed. The incidence of asthma and rhinitis episodes was registered. Results showed that students were exposed to PM2.5 concentrations that exceed the World Health Organization recommended levels. A marked sea influence in the aerosol characteristics was identified by the use of air masses trajectories and by the concentrations of chloride, sodium and magnesium.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Canha, M. Freitas, M. Almeida-Silva, S. Almeida, H. Dung, I. Dionísio, J. Cardoso, C. Pio, A. Caseiro, T. Verburg, and H. Wolterbeek

Abstract  

One Plus Sequential Air Sampler—Partisol was placed in a small village (Foros de Arrão) in central Portugal to collect PM10 (particles with an aerodynamic diameter below 10 μm), during the winter period for 3 months (December 2009–March 2010). Particles masses were gravimetrically determined and the filters were analyzed by instrumental neutron activation analysis to assess their chemical composition. The water-soluble ion compositions of the collected particles were determined by Ion-exchange Chromatography. Principal component analysis was applied to the data set of chemical elements and soluble ions to assess the main sources of the air pollutants. The use of both analytical techniques provided information about elemental solubility, such as for potassium, which was important to differentiate sources.

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