Teresa Moreno

Association between traffic-related air pollution in schools and cognitive development in primary school children: a prospective cohort study.

Background Air pollution is a suspected developmental neurotoxicant. Many schools are located in close proximity to busy roads, and traffic air pollution peaks when children are at school. We aimed to assess whether exposure of children in primary school to traffic-related air pollutants is associated with impaired cognitive development. Methods and Findings We conducted a prospective study of children (n = 2,715, aged 7 to 10 y) from 39 schools in Barcelona (Catalonia, Spain) exposed to high and low traffic-related air pollution, paired by school socioeconomic index; children were tested four times (i.e., to assess the 12-mo developmental trajectories) via computerized tests (n = 10,112). Chronic traffic air pollution (elemental carbon [EC], nitrogen dioxide [NO2], and ultrafine particle number [UFP; 10–700 nm]) was measured twice during 1-wk campaigns both in the courtyard (outdoor) and inside the classroom (indoor) simultaneously in each school pair. Cognitive development was assessed with the n-back and the attentional network tests, in particular, working memory (two-back detectability), superior working memory (three-back detectability), and inattentiveness (hit reaction time standard error). Linear mixed effects models were adjusted for age, sex, maternal education, socioeconomic status, and air pollution exposure at home. Children from highly polluted schools had a smaller growth in cognitive development than children from the paired lowly polluted schools, both in crude and adjusted models (e.g., 7.4% [95% CI 5.6%–8.8%] versus 11.5% [95% CI 8.9%–12.5%] improvement in working memory, p = 0.0024). Cogently, children attending schools with higher levels of EC, NO2, and UFP both indoors and outdoors experienced substantially smaller growth in all the cognitive measurements; for example, a change from the first to the fourth quartile in indoor EC reduced the gain in working memory by 13.0% (95% CI 4.2%–23.1%). Residual confounding for social class could not be discarded completely; however, the associations remained in stratified analyses (e.g., for type of school or high-/low-polluted area) and after additional adjustments (e.g., for commuting, educational quality, or smoking at home), contradicting a potential residual confounding explanation. Conclusions Children attending schools with higher traffic-related air pollution had a smaller improvement in cognitive development.

Child exposure to indoor and outdoor air pollutants in schools in Barcelona, Spain

Proximity to road traffic involves higher health risks because of atmospheric pollutants. In addition to outdoor air, indoor air quality contributes to overall exposure. In the framework of the BREATHE study, indoor and outdoor air pollution was assessed in 39 schools in Barcelona. The study quantifies indoor and outdoor air quality during school hours of the BREATHE schools. High levels of fine particles (PM2.5), nitrogen dioxide (NO2), equivalent black carbon (EBC), ultrafine particle (UFP) number concentration and road traffic related trace metals were detected in school playgrounds and indoor environments. PM2.5 almost doubled (factor of 1.7) the usual urban background (UB) levels reported for Barcelona owing to high school-sourced PM2.5 contributions: [1] an indoor-generated source characterised mainly by organic carbon (OC) from organic textile fibres, cooking and other organic emissions, and by calcium and strontium (chalk dust) and; [2] mineral elements from sand-filled playgrounds, detected both indoors and outdoors. The levels of mineral elements are unusually high in PM2.5 because of the breakdown of mineral particles during playground activities. Moreover, anthropogenic PM components (such as OC and arsenic) are dry/wet deposited in this mineral matter. Therefore, PM2.5 cannot be considered a good tracer of traffic emissions in schools despite being influenced by them. On the other hand, outdoor NO2, EBC, UFP, and antimony appear to be good indicators of traffic emissions. The concentrations of NO2 are 1.2 times higher at schools than UB, suggesting the proximity of some schools to road traffic. Indoor levels of these traffic-sourced pollutants are very similar to those detected outdoors, indicating easy penetration of atmospheric pollutants. Spatial variation shows higher levels of EBC, NO2, UFP and, partially, PM2.5 in schools in the centre than in the outskirts of Barcelona, highlighting the influence of traffic emissions. Mean child exposure to pollutants in schools in Barcelona attains intermediate levels between UB and traffic stations.

An introductory TEM study of Fe-nanominerals within coal fly ash.

The investigation presented here was conducted during a wider experiment on the technical feasibility and environmental impacts of tire combustion in a Brazilian coal-fired power station. Nanometric-sized crystalline phases in fly ash were characterised using energy-dispersive X-ray spectrometer (EDS) and high-resolution transmission electron microscopy (HR-TEM) images. The nanoparticles, which register abundance peaks at 10 nm and 100 nm, include iron-rich oxide (e.g. hematite), Fe-sulphate (e.g., yavapaiite: KFe(SO4)2), and Fe-aluminumsilicate glass. Individual metalliferous nanoparticles have a heterogeneous microstructure in which elements such as iron, aluminum and silicon are not uniformly distributed. HR-TEM offers a powerful analytical technique in the study of fly ash nanoparticles, providing a better understanding of the detailed chemistry of this potentially strongly bioreactive component of atmospheric particulate matter.

The Geology of Chile

This book is the first comprehensive account in English of the geology of Chile, providing a key reference work that brings together many years of research, and written mostly by Chilean authors from various universities and other centres of research excellence. The 13 chapters begin with a general overview, followed by detailed accounts of Andean tectonostratigraphy and magmatism, the amazingly active volcanism, the world class ore deposits that have proven to be so critical to the welfare of the country, and Chilean water resources. The subject then turns to geophysics with an examination of neotectonics and earthquakes, the hazardous frequency of which is a daily fact of life for the Chilean population. There are chapters on the offshore geology and oceanography of the SE Pacific Ocean, subjects that continue to attract much research not least from those seeking to understand world climatic variations, and on late Quaternary land environments, concluding with an account examining human colonization of southernmost America. During his voyage on H.M.S. Beagle , an extended visit to Chile (1834-35) had a profound impact on Charles Darwin, especially on his understanding of volcanoes, earthquakes and tsunamis. Over more recent decades scientists have come to recognize the Chilean Andes as providing the classic example of a mountain belt produced by oceanic subduction beneath a continent, as well as some of the most dramatic scenic and climatic variations on Earth. In the final chapter, the editors offer a description of a drive from the Mediterranean landscapes of central Chile to the hyperarid Atacama Desert, a contribution designed to give visitors a chance to experience for themselves the geology and scenery of this extraordinary country.

Variations in vanadium, nickel and lanthanoid element concentrations in urban air

The emission of trace metal pollutants by industry and transport takes place on a scale large enough to alter atmospheric chemistry and results in measurable differences between the urban background of inhalable particulate matter (PM) in different towns. This is particularly well demonstrated by the technogenic release into the atmosphere of V, Ni, and lanthanoid elements. We compare PM concentrations of these metals in large datasets from five industrial towns in Spain variously influenced by emissions from refinery, power station, shipping, stainless steel, ceramic tiles and brick-making. Increased La/Ce values in urban background inhalable PM, due to La-contamination from refineries and their residual products (fuel oils and petcoke), contrast with Ce-rich emissions from the ceramic related industry, and clearly demonstrate the value of this ratio as a sensitive and reliable tracer for many point source emissions. Similarly, anomalously high V/Ni values (>4) can detect the influence of nearby high-V petcoke and fuel oil combustion, although the use of this ratio in urban background PM is limited by overlapping values in natural and anthropogenic materials. Geochemical characterisation of urban background PM is a valuable compliment to the physical monitoring of aerosols widely employed in urban areas, especially given the relevance of trace metal inhalation to urban health issues.

Biomass burning contributions to urban aerosols in a coastal Mediterranean City

Mean annual biomass burning contributions to the bulk particulate matter (PM(X)) load were quantified in a southern-European urban environment (Barcelona, Spain) with special attention to typical Mediterranean winter and summer conditions. In spite of the complexity of the local air pollution cocktail and the expected low contribution of biomass burning emissions to PM levels in Southern Europe, the impact of these emissions was detected at an urban background site by means of tracers such as levoglucosan, K(+) and organic carbon (OC). The significant correlation between levoglucosan and OC (r(2)=0.77) and K(+) (r(2)=0.65), as well as a marked day/night variability of the levoglucosan levels and levoglucosan/OC ratios was indicative of the contribution from regional scale biomass burning emissions during night-time transported by land breezes. In addition, on specific days (21-22 March), the contribution from long-range transported biomass burning aerosols was detected. Quantification of the contribution of biomass burning aerosols to PM levels on an annual basis was possible by means of the Multilinear Engine (ME). Biomass burning emissions accounted for 3% of PM(10) and PM(2.5) (annual mean), while this percentage increased up to 5% of PM(1). During the winter period, regional-scale biomass burning emissions (agricultural waste burning) were estimated to contribute with 7±4% of PM(2.5) aerosols during night-time (period when emissions were clearly detected). Long-range transported biomass burning aerosols (possibly from forest fires and/or agricultural waste burning) accounted for 5±2% of PM(2.5) during specific episodes. Annually, biomass burning emissions accounted for 19%-21% of OC levels in PM(10), PM(2.5) and PM(1). The contribution of this source to K(+) ranged between 48% for PM(10) and 97% for PM(1) (annual mean). Results for K(+) from biomass burning evidenced that this tracer is mostly emitted in the fine fraction, and thus coarse K(+) could not be taken as an appropriate tracer of biomass burning.

Health effects from Sahara dust episodes in Europe: literature review and research gaps.

The adverse consequences of particulate matter (PM) on human health have been well documented. Recently, special attention has been given to mineral dust particles, which may be a serious health threat. The main global source of atmospheric mineral dust is the Sahara desert, which produces about half of the annual mineral dust. Sahara dust transport can lead to PM levels that substantially exceed the established limit values. A review was undertaken using the ISI web of knowledge database with the objective to identify all studies presenting results on the potential health impact from Sahara dust particles. The review of the literature shows that the association of fine particles, PM₂.₅, with total or cause-specific daily mortality is not significant during Saharan dust intrusions. However, regarding coarser fractions PM₁₀ and PM₂.₅₋₁₀ an explicit answer cannot be given. Some of the published studies state that they increase mortality during Sahara dust days while other studies find no association between mortality and PM₁₀ or PM₂.₅₋₁₀. The main conclusion of this review is that health impact of Saharan dust outbreaks needs to be further explored. Considering the diverse outcomes for PM₁₀ and PM₂.₅₋₁₀, future studies should focus on the chemical characterization and potential toxicity of coarse particles transported from Sahara desert mixed or not with anthropogenic pollutants. The results of this review may be considered to establish the objectives and strategies of a new European directive on ambient air quality. An implication for public policy in Europe is that to protect public health, anthropogenic sources of particulate pollution need to be more rigorously controlled in areas highly impacted by the Sahara dust.

Particle-induced oxidative damage is ameliorated by pulmonary antioxidants

This investigation focuses on the application of an in vitro assay in elucidating the role of lung lining fluid antioxidants in the protection against inhaled particles, and to investigate the source of bioreactivity in urban PM10 collections from South Wales. The Plasmid Assay is an in vitro method of assessing and comparing the oxidative bioreactivity of inhalable particles. This method has provided the basis of limited toxicological studies into various inhaled xenobiotics including asbestos, and more recently PM10. Carbon Black M120 and Diesel Exhaust Particles (DEP) were tested as PM10 surrogates, DEP displaying the greatest oxidative bioreactivity. Both urban PM2.5 (fine fraction) and PM2.5-10 (coarse fraction) (Cardiff, S. Wales, UK) caused significant damage, the coarse fraction displaying higher oxidative capacity. The soluble components were found to be responsible for most of the bioreactivity in both PM sizes. Low molecular components of fresh lung lavage were found to offer most antioxidant protection, and surrogate Epithelial Lining Fluid (sELF) showed significant amelioration of DNA damage by the coarse fraction but less effect against the fine. Overall, the coarse, soluble fraction of PM10 is a great source of oxidative bioreactivity, but natural pulmonary low molecular weight antioxidants can significantly ameliorate its effects.

Health impact assessment of a reduction in ambient PM2.5 levels in Spain

BACKGROUND Health effects linked to exposure to high air pollutant levels have been described in depth, and many recent epidemiologic studies have also consistently reported positive associations between exposure to air pollutants at low concentrations (particularly PM(2.5)) and adverse health outcomes. OBJECTIVE To estimate the number of avoidable deaths associated with reducing PM(2.5) levels in Spain. MATERIALS AND METHODS For exposure assessment, we used the US Environmental Protection Agencys Community Multiscale Air Quality model to simulate air pollution levels with a spatial resolution of 18×18 km(2). Two different scenarios were compared, namely, a baseline 2004 scenario based on Spains National Emissions Inventory and a projected 2011 scenario in which a reduction in PM(2.5) was estimated on the basis of the benefits that might be attained if specific air quality policies were implemented. Using an 18×18 km(2) grid, air pollution data were estimated for the entire Iberian Peninsula, the Balearic Islands, Ceuta and Melilla. For these strata, crude all-cause mortality rates (ICD-10: A00-Y98) were then calculated for the over-30 and 25-74 age groups, taking into account the 2004 population figures corresponding to these same age groups, selected in accordance with the concentration-response functions (Pope CA 3rd, Burnett RT, Thun MJ, Calle EE, Krewski D, Ito K et al. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution. JAMA 2002; 287:1132-41; Laden F, Schwartz J, Speizer FE, Dockery DW. Reduction in fine particulate air pollution and mortality: extended follow-up of the Harvard Six Cities study. Am J Respir Crit Care Med 2006; 173:667-72.). Health impacts were assessed using the Environmental Benefits Mapping and Analysis Program (BenMAP). RESULTS Air quality improvement was defined as an average annual reduction of 0.7 μg/m(3) in PM(2.5) levels. Using long-term health impact assessment analysis, we estimated that 1720 (673-2760) all-cause deaths (6 per 100,000 population) in the over-30 age group and 1450 (780-2108) all-cause deaths (5 per 100,000 population) in the 25-74 age group could be prevented annually. CONCLUSIONS The results showed the potential benefits in general mortality which could be expected if pollution control policies were successfully implemented by 2011. A specifically adapted BenMAP could be used as a tool for estimating health impacts associated with changes in air pollution in Spain.

2001–2012 trends on air quality in Spain

This study aims at interpreting the 2001-2012 trends of major air pollutants in Spain, with a major focus on evaluating their relationship with those of the national emission inventories (NEI) and policy actions. Marked downward concentration trends were evidenced for PM10, PM2.5 and CO. Concentrations of NO2 and NOx also declined but in a lesser proportion at rural and traffic sites. At rural sites O3 has been kept constant, whereas it clearly increased at urban and industrial sites. Comparison of the air quality trends and major inflection points with those from NEIs, the National Energy Consumption and the calendar of the implementation of major policy actions allowed us to clearly identify major benefits of European directives on power generation and industrial sources (such as the Large Combustion Plants and the Integrated Pollution Prevention and Control Directives). This, together with a sharp 2007-2008 decrease of coal consumption has probably caused the marked parallel decline of SO2, NOx and for PM2.5 concentrations. Also the effect of the EURO 4 and 5 vehicle emission standards on decreasing emissions of PM and CO from vehicles is noticeable. The smooth decline in NO2-NOx levels is mostly attributed to the low efficiency of EURO 4 and 5 standards in reducing real life urban driving NO2 emissions. The low NOx decrease together with the complexity of the reactions of O3 formation is responsible for the constant O3 concentrations, or even the urban increase. The financial crisis has also contributed to the decrease of the ambient concentration of pollutants; however this caused a major reduction of the primary energy consumption from 2008 to 2009, and not from 2007 to 2008 when ambient air PM and SO2 sharply decreased. The meteorological influence was characterized by a 2008-2012 period favorable to the dispersion of pollutants when compared to the 2001-2007.