Implementation of various hypothetical low emission zone scenarios in Greater Paris: Assessment of fine-scale reduction in exposure and expected health benefits.

OBJECTIVES: Literature assessing the effects of policies aimed at reducing traffic-related air pollution is scarce. The aims of this study were to evaluate the expected impacts, in terms of air quality and health effects, of various hypothetical low-emission zone (LEZ) scenarios in Greater Paris for a planned intervention in 2018/2019 which combine two different perimeters and two levels of vehicles ban, and to assess those impacts according to the socioeconomic status (SES) of the population. METHODS: We evaluated the effects of four hypothetical LEZ scenarios on various stages of the full-chain model, more specifically, road traffic modelling (traffic flow, type of vehicles and related number of kilometers driven), emissions, fine scale PM2.5 and NO2 concentrations, related resident population exposure, and health effects. We computed the overall benefits of expected air pollution improvements in terms of preventable deaths and a decrease in new cases of the following three major chronic diseases: ischemic heart diseases in adults, asthma in children and low weight in full-term newborns. RESULTS: The most stringent LEZ scenario would lower the maximum level of exposure from 55 µg/m3 to 42 µg/m3 in Paris. In one year, this scenario would help prevent: 340 deaths (-0.6%) representing 114,300 life years gained, 170 low-weight full-term births (-4.9%), 130 new cases of ischemic heart disease (IHD) (-1.8%) and 2930 new cases of asthma (-3.0%) among 9.4 million residents. Residents outside the LEZ would also benefit from this scenario. Results indicated that the intervention could contribute to increasing inequalities. The comparison of scenarios underlined the value of extending the LEZ to include a wider zone (including 80 more municipalities surrounding Paris). This would lead to a more equitable spread of the benefits over the population. CONCLUSION: Traffic control policies such as LEZ are difficult to accept for some categories of commuters and economic stakeholders. As of June 2019, the concertation process for the proposed Paris LEZ is still ongoing. This work provides authorities with detailed analyses of the options for this measure as well as information on related implications. It will help decision makers prioritize which preventive measures to introduce.

Analyzing effect modifiers of the temperature-mortality relationship in the Paris region to identify social and environmental levers for more effective adaptation to heat.

Adaptation to heat is a major challenge for the Paris region (France). Based on fine-scale data for the 1,287 municipalities of the region over 2000-2017, we analyzed (time-serie design) the temperature-mortality relationship by territories (urban, suburban, rural), age (15-64 and ≥ 65) and sex, and explored how it was modified by vegetation and socio-economic indicators. Heat was associated with an increased mortality risk for all territories, age groups, sex, and mortality causes. Women aged 65 and over residing in the most deprived municipalities had a relative risk (RR) of deaths at 29.4 °C (compared to 16.6 °C) of 4.2 [3.8:4.5], while the RR was 3.4 [3.2:3.7] for women living in less deprived municipalities. Actions to reduce such sex and social inequities should be central in heat adaptation policy.

Greening is a promising but likely insufficient adaptation strategy to limit the health impacts of extreme heat.

BACKGROUND: Adapting the urban environment to heat is a public health priority in the context of climate change. Cities are now considering interventions on specific urban characteristics known to contribute to the urban heat island (UHI) such as vegetation and imperviousness. OBJECTIVES: To explore how these urban characteristics influence the temperature-mortality relationship in the Paris region. METHODS: We modeled the temperature-mortality relationship for the 1300 municipalities of the region from 1990 to 2015, while including an interaction with indicators that summarize the municipalities' main urban characteristics. Four indicators were tested: lack of green spaces, lack of trees, proportion of impervious surface, and overexposed population to a potential night UHI. RESULTS: The shape of the temperature-mortality relationship was similar across all municipalities, but with a higher slope at the highest temperatures in municipalities with less green spaces, less trees, and more impervious soil. For instance, in Paris and its close suburbs, the relative risk associated with a temperature in the 99th percentile of the temperature distribution (compared to the 50th percentile) was 2.17 [IC95% 1.98:2.38] in municipalities with 40% of their surface covered by trees compared to 2.57 [IC 95% 2.47:2.68] in municipalities with only 3% of their surface covered by trees. DISCUSSION: A lack of vegetation and a high degree of imperviousness were associated with a higher risk of heat-related mortality in the Paris region. Therefore, we can assume that interventions targeting these characteristics could reduce the health impacts of extreme heat. Such interventions should be coupled with other initiatives such as protecting the most vulnerable and promoting appropriate behaviors.

[Estimating emergency hospital admissions to gauge short-term effects of air pollution: evaluation of health data quality]. / Estimation des hospitalisations en urgence pour mesurer les effets à court terme de la pollution atmosphérique : qualité des données issues du PMSI.

The study of the short-term effects and health impact of air pollution is carrier out by the ERPURS regional surveillance program which utilizes hospitalization data obtained from the French hospital information system (PMSI) to determine these links. This system does not permit the distinction between emergency hospital admissions from scheduled ones, which cannot be related to short term changes in air pollution levels. This study examines how scheduled admissions affect the quality of the health indicators used to estimate air pollution effects. This indicator is compared to three new emergency hospitalisation indicators reconstructed based on data from the public hospitals in Paris, partly from the PMSI data and partly with data from an on-line emergency network that regroups all of the computerized emergency services. According to the pathology, scheduled admissions present a difficulty which affects the capacity to highlight the weakest risks with any precision.

The mortality impacts of fine particles in France.

INTRODUCTION: Worldwide, air pollution has become a main environmental cause of premature mortality. This burden is largely due to fine particles. Recent cohort studies have confirmed the health risks associated with chronic exposure to PM2.5 for European and French populations. We assessed the mortality impact of PM2.5 in continental France using these new results. METHODS: Based on a meta-analysis of French and European cohorts, we computed a shrunken estimate of PM2.5-mortality relationship for the French population (RR 1.15 [1.05:1.25] for a 10µg/m(3) increase in PM2.5). This RR was applied to PM2.5 annual concentrations estimated at a fine spatial scale, using a classical health impacts assessment method. The health benefits associated with alternative scenarios of improving air quality were computed for 36,219 French municipalities for 2007-2008. RESULTS: 9% of the total mortality in continental France is attributable to anthropogenic PM2.5. This represents >48,000 deaths per year, and 950,000years of life lost per year, more than half occurring in urban areas larger than 100,000 inhabitants. If none of the municipalities exceeded the World Health Organization guideline value for PM2.5 (10µg/m(3)), the total mortality could be decreased by 3%, corresponding to 400,000years of life saved per year. CONCLUSION: Results were consistent with previous estimates of the long-term mortality impacts of fine particles in France. These findings show that further actions to improve air quality in France would substantially improve health.