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Schiltigheim, France

Favez O.,INERIS | Petit J.-E.,INERIS | Petit J.-E.,French Climate and Environment Sciences Laboratory | Bessagnet B.,INERIS | And 20 more authors.
Pollution Atmospherique | Year: 2012

This paper aims at gaining an insight into the PM10 daily threshold (50 ug/m3) exceedances measured by French regional air quality monitoring networks for the last four years. As almost three quarter of these exceedances happens to occur between November and April, we focus here on such winter (broadly speaking) pollution episodes. The deployment of monitoring devices allowing for a proper account of semi-volatile material within PM10 was achieved concomitantly to the development particulate pollution episodes largely influenced by ammonium nitrate (which is semi-volatile) in March-April 2007. Since then, such pollution events are frequently observed at this period of the year, notably due to stable meteorological conditions favoring the condensation of semi-volatile material into the particulate phase along with the resumption of manure spreading, which constitutes a major source of ammonium nitrate gaseous precursors (at least at some points of the year). Such pollution events, which are also related to combustion emissions (among which mobile sources) are typically preceded, from November to February, by frequent daily threshold exceedances with potentially significant influences of biomass burning (e.g. residential wood burning). The winter period is also impacted by long range transport episodes, corresponding notably to increases of ammonium sulfate relative abundances within PM10. Moreover, as traffic sites are generally the first ones showing PM10 exceedances due the increment of direct emissions and resuspension processes, mobile sources are also considered as a major target for action plans. Finally, it is underlined that the occurrence of daily threshold exceedances is highly influenced by meteorological conditions, so that the yearly number of these exceedances shows well-marked inter-annual variations, with 2009 and 2011 (and 2012, but not shown here) being significantly more polluted than 2008 and 2010. The on-going development of efficient forecasting systems still suffer lacks of detailed emission inventories and strong knowledge on the physical and chemical transformation processes of particles and their gaseous precursors within the boundary layer.

Bentayeb M.,French Institute for Public Health Surveillance InVS | Stempfelet M.,French Institute for Public Health Surveillance InVS | Wagner V.,French Institute for Public Health Surveillance InVS | Zins M.,University of Versailles | And 14 more authors.
Atmospheric Environment | Year: 2014

Introduction: Exposure to air pollution has been associated to mortality and morbidity in numerous studies. However, few studies assessed retrospectively long-term exposure at a fine spatial scale. Aims: To contribute to the assessment of long-term exposure to air pollution of participants from the French GAZEL cohort, we estimated atmospheric PM10, PM2.5, NO2, SO2, C6H6 and O3 levels at 2km resolution over France, from 1989 to 2008. Methods: The spatiotemporal concentrations of selected air pollutants were estimated at a fine scale by combining (1) the CHIMERE chemistry-transport model (2) mesh refinement and (3) data assimilation with geostatistical analyzes. Assimilated concentrations were assigned to participants according to their residential zip codes, taking into account residential history. Results: Despite a decreasing trend in concentrations for all pollutant concentrations, levels remained high in some French regions, especially for PM, NO2 and O3.Annual median concentrations at the cohort participants' zip code of PM10, PM2.5, NO2 and O3 were decreased from 1989 to 2008 by 27%, 29%, 40% and 16%, respectively. The largest decreases occurred for SO2 (86%) and C6H6 (85%).Validation showed high correlations between observations and final modeled data (R above 0.75 in 2007) for PM10, NO2 and O3. Conclusion: The modeling process enabled us to assess air pollution over 20 years (1989-2008) at a fine-geographical scale, with acceptable agreement being found between observations and models for all pollutants. © 2014 Elsevier Ltd.

Laurent O.,Laboratoire Detude Et Of Recherche En Santepublique | Benichou J.,French Institute of Health and Medical Research | Pedrono G.,SEPIA Sante | Segala C.,SEPIA Sante | And 5 more authors.
Environnement, Risques et Sante | Year: 2012

It is increasingly suspected that the health impact of air pollution may be greater among socioeconomically disadvantaged populations than among those who are better off. However, health impact assessments of air pollution generally do not take socioeconomic status into account. In this paper, we propose an approach to the quantitative estimation of the short-term impacts of environmental risk factors such as air pollution among socioeconomically contrasted populations. We do so through an illustrative case study of ambient air pollution and emergency calls for asthma attacks in Strasbourg (France). Next, we discuss the potential advantages of this approach as well as its current limitations, and then look at the research needs that must be addressed to improve its applicability. Among these, the most urgent appear to be the needs for improved exposure estimates and for large-scale epidemiological studies that use harmonized methods to investigate the modification by socioeconomic status and other factors of the effects of air pollution. Case-crossover designs offer promising perspectives for that purpose, especially as more accurate and individualized estimates of air pollution exposure become available for epidemiological studies.

Carnevale C.,University of Brescia | Finzi G.,University of Brescia | Pederzoli A.,University of Brescia | Turrini E.,University of Brescia | And 13 more authors.
Science of the Total Environment | Year: 2014

When designing air pollution reduction policies, regional decision makers face a limited budget to choose the most efficient measures which will have impacts on several pollutants in different ways. RIAT+ is a regional integrated assessment tool that supports the policy maker in this selection of the optimal emission reduction technologies, to improve air quality at minimum costs. In this paper, this tool is formalized and applied to the specific case of a French region (Alsace), to illustrate how focusing on one single pollutant may exacerbate problems related to other pollutants, on top of conflicts related to budget allocation. In our case, results are shown for possible trade-offs between NO2 and O3 control policies. The paper suggests an approach to prioritize policy maker objectives when planning air pollution policies at regional scale. © 2014 Elsevier B.V.

Ten years after their implementation, the Alsatian prefectorial orders concerning emergency measures applied in case of exceedance of alert thresholds for ozone, nitrogen dioxide and, a pioneer feature of the French region, the PM, required an update. In 2007, the ASPA was mandated by the Bas-Rhin and the Haut-Rhin Prefectures to define and assess new emergency measures. The Alsatian emissions inventory first identified the activity sectors which would be potentially targeted by the measures, and then calculated the associated emission reductions. In association with the transportation agency, 3 scenarios were retained for concentration simulation: limitation of the speed limit at 70 km/h on freeways and major urban roads, alternated traffic in towns, and a combination of both measures. Then, an integrated modelling chain, including the CHIMERE and ADMS-Urban models, was allowed to simulate, for the three scenarios, the variation of ozone during the heat wave of 2003, and the variation of nitrogen dioxide and the PM during wintry episodes, for the cities of Strasbourg, Colmar and Mulhouse. Finally, the urban cartographies of the impact of the scenarios on the concentrations were crossed with the georeferenced residence data to estimate the population affected by threshold exceedances in each case. A weak impact was obtained for speed limit reduction, while it was significant for the alternated traffic; for the PM, the concentrations fell about 10 μg/m 3 and the population exposed to threshold exceedance fell by a factor 4; for nitrogen dioxide, the concentrations were lowered by several dozen μg/m 3 and the exposed population fell by a factor 2; whereas for ozone, we noted a slight increase in the concentration and the exposed population. At the same time as the implementation of the newly developed emergency measures, the evolution of knowledge and modelling shows that it would be technically justified to differentiate the measures, pollutant by pollutant. © 2011 INRETS et Springer-Verlag France.

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