La qualité de l'air dans les agglomérations françaises : l'exemple des concentrations de dioxyde d'azote

Cet article met en évidence des types d'organisation de la pollution journalière par le dioxyde d'azote dans 54 aires urbaines françaises

Building comparable synthetic health-related indicators of air quality in cities

Working on the relationship between respiratory health and atmospheric pollution in French cities led us to adopt a perspective that considers the risk for a single city of showing high levels of respiratory health problems. The risk level in a city is dependent on population vulnerability, the city context and pollutant levels. This presentation focuses on the observation of the unequal pollution hazards in French cities on a macro-scale. The study field covers 34 French cities of more than 100,000 inhabitants. The aim is to build comparable synthetic indicators of atmospheric pollution that consider the temporal and spatial diversity within a city, and to compare the different results. The focus is on the results for nitrogen dioxide (NO2) over the 2007 and 2008 winter season. The paper presents the database and methodology used. The findings show that the spatial structure of air pollution between the cities remains globally the same whatever the indicator chosen. However, the results also show significant changes in the relative position of certain cities. When comparing the more conventional indicator calculated from mean daily concentrations in urban monitoring sites with an indicator also taking into account the concentrations observed in roadside stations, relative changes appear for more than ten cites. These findings highlight the importance of the criteria used in the choice of the indicators, and the benefit of using a set of complementary indicators in epidemiological studies

Risque, Vulnérabilité, Résilience : comment les définir dans le cadre d'une étude géographique sur la santé et la pollution atmosphérique en milieu urbain ?

This chapter offers an insight in the concept of sanitary risk in french cities. It attempts to define risk, alea and vulnerability when applied to the observation of atmospheric pollution and respiratory health.Cet article propose une réflexion sur la notion de risque sanitaire dans le système des villes françaises. Cette réflexion s'appuie sur une proposition de définition des notions de risque, d'aléa et de vulnérabilité appliquées à la santé respiratoire dans les villes françaises. On y met en évidence l'inégalité du risque selon les villes, en tenant compte des facteurs établissant l'état de santé d'une population

Les différenciations interurbaines de santé : une mesure par les hospitalisations

On examine dans ce texte la répartition de quelques diagnostics pour des pathologies respiratoires en lien avec la pollution dans les 54 aires urbaines françaises de plus de 100000 habitants en 1999. L'examen met en lumière une opposition nette entre les villes du nord et de l'est de la France où les taux de morbidité associés à ces diagnostics sont élevés et les villes du sud où ces taux sont plus faibles

La santé respiratoire dans les villes françaises : une caractérisation par les hospitalisations

A paraître dans la revue 'Environnement, Risques et Santé', c/o John Libbey EurotextA range of respiratory diseases related to air pollution has been the focus of this study. We have been looking at hospital admissions in 2000 in the largest 54 french urban areas. There is a clear regional effect, opposing northen and north-eastern cities were the level of admission is high to south-western cities were it is much weaker. City size does not matter.On a examiné les différences que la répartition de quelques pathologies respiratoires en lien avec la pollution introduit entre 54 villes françaises, à partir du fichier des hospitalisations dans les établissements publics en 2000. On met ainsi en avant une opposition entre des villes du nord et de l'est. La taille des villes semble avoir peu d'effets sur la répartition

Gold( i )-catalyzed addition of aldehydes to cyclopropylidene bearing 6-aryl-1,5-enynes

A diastereoselective, gold-catalyzed cascading cycloisomerization of alkylidene cyclopropane bearing 1,5-enynes that terminates in a cyclo-addition of aldehydes has been developed

Life Cycle Inventory for Use of Waste Solvent as Fuel Substitute in the Cement Industry - A Multi-Input Allocation Model (11 pp)

Background: The Swiss chemical industry produces large amounts of organic waste solvents. Some of these solvents cannot be recovered. A common option for the treatment of such organic waste solvents is the incineration in hazardous waste incinerators. Alternatively, the waste solvents can be used as fuel in cement production. On the one hand, solvent incineration in cement kilns saves fossil fuels such as coal and heavy fuel oil. On the other hand, fuel-bound emissions may change as well. These emission changes can either have a negative or a positive net ecological impact, depending on the chemical nature of the waste solvent used. Goal and Scope: The aim of our work was to develop a multi-input allocation model, which allows one to calculate life cycle inventories for specific waste solvents. These LCIs can then be used in further applications, e.g. a comparison of different waste solvent treatment options. Results and Discussion: A multi-input allocation model was developed that takes into account the physico-chemical properties of waste solvents such as elementary composition and net calorific value. The model is based on a set of equations and data on fuel mix, fuel composition as well as transfer coefficients for heavy metals. The model calculates "avoided inputs” and "changes in emissions” which arise from substituting fossil fuels with waste solvents. Life cycle inventories can be calculated for specific waste solvents if the elementary composition and the net calorific value are known. The application of the model is illustrated in a case study on four waste solvents. The results show that solvent incineration in cement kilns generally reduces the overall impact of clinker production because fossil fuels are replaced. A sensitivity analysis revealed that the model is especially sensitive to the fuel mix and coal properties, such as net calorific value as well as the content of nitrogen and carbon. The transfer coefficients are also uncertain, but this uncertainty is not relevant as the amount of heavy metal emitted into the atmosphere is small. Conclusions and Outlook: The proposed model serves to calculate inventory data for the combustion of liquid alternative fuels such as waste solvents in cement kilns. Although our model represents Swiss cement production conditions, it can be applied to other countries by fitting the most sensitive parameters of fuel mix and coal properties. In case the technology used is very different to the Swiss situation, the transfer coefficients also need to be adapte

A multi-national comparison of meat eaters' attitudes and expectations for burgers containing beef, pea or algae protein

Within recent years, demand as well as supply of products to replace meat, so called meat alternatives, have increased. For future products, new plant-based protein sources are of high interest. Protein from pea and especially from algae provide huge potential for human nutrition as well as for the environment. To provide insight on consumers' opinions on the development of new meat alternatives, this study investigated consumers' opinions of pea and algae burgers compared to the traditional beef burger in terms of taste, health, and environmental friendliness. It has also explored the influence of factors such as meat commitment, food neophobia, and the attitude towards vegetarians and vegans; it has then compared the findings between three European countries with different culinary backgrounds. The online survey was conducted with meat-eating participants from Germany (N=567), France (N=605), and the United Kingdom (N=562). Participants in all three countries expected pea and algae burgers to be less tasty, but healthier and more environmentally friendly compared to the beef burger. Expectations of taste, health, and environmental friendliness of pea and algae burgers were negatively influenced by higher levels of meat commitment, more negative attitudes towards vegetarian and vegan lifestyles, and higher food neophobia. Although the attitudes towards vegetarian lifestyles were generally negative, pea and algae emerged as promising protein sources because of their favorable health and environmental friendliness expectations. Nevertheless, negative taste expectations and attitudes towards meat-free diets remain a challenge for the adoption of more plant-based diets.Peer reviewe

Aftershock sequence of the 1994, Mw 6.8, Liwa earthquake (Indonesia): seismic rupture process in a volcanic arc

International audienceWe present the aftershock activity following the February 15, 1994, Mw 6.8 earthquake which was strongly felt in southern Sumatra, Indonesia, near the Great Sumatran Fault (GSF). At this place, the slip rate is supposed to be low; neverthless, three M>6 events occurred along this segment during this century. No significant instrumental microseismi-city has ever been recorded there. We use data from both the regional Indonesian network and a local seismic array operating 11 days after the mainshock during one month. Aftershocks mostly locate in a broad zone of 55x20 km 2 near two active NW-trending strike-slip segments of the GSF separated by a recent caldera, Suwoh. During the experiment, the NW segment (from Suwoh up to 15 km SE of the Ranau lake caldera, an old right-stepover pull-apart) was very active. As first suggested by the aftershock distribution and the lack of coseismic rupture at the surface, the 20 focal mechanisms determined provide evidence for various post-seismic stress adjustments on secondary faults located in the Ranau-Suwoh paleo-pull-apart graben. Less than 20% of the aftershocks are directly linked to the main rupture, a nearly pure right-lateral strike-slip faulting reaching 25 km depth. A narrow seismic gap underlines the active volcanic area of Suwoh. We conclude that the rupture process along the GSF is controlled both by volcanism and structures, and that the volcanic activity affects the mechanical properties of the crust only in a narrow zone