The environmental justice implications of the Paris low emission zone: a health and economic impact assessment

Background Reducing the mortality burden associated with urban air pollution constitutes a public health priority, and evidence of unequal exposure and susceptibility across population subgroups is growing. Many European countries have implemented low emission zones (LEZs) in densely populated city centers. Although LEZs decrease air pollution exposure and health impacts, evidence is lacking on their impact across neighborhoods and socio-economic groups. Objectives The aim of this study was to evaluate the most equitable approach to implementing the second phase of the LEZ in Paris, France. We also present a literature review of the studies evaluating the benefits associated with LEZs in Europe. Methods A health impact assessment (HIA) was conducted to quantify changes in air pollution exposure and expected health benefits by socioeconomic group and neighborhood related to four hypothetical scenarios for the second phase of the LEZ based on French Deprivation Index scores. The study focused on NO 2 and PM 2.5 as air pollutants and evaluated the impact of the LEZ on the inequitable burden of childhood asthma and all-cause premature adult mortality. We also conducted an economic evaluation associated with the LEZ benefits on prevented deaths and asthma cases. Results The scenario with the largest LEZ perimeter and the most stringent vehicle standards prevented the highest number of cases and produced the most equitable distribution of health benefits, especially childhood asthma. It is expected that 810 deaths and 3200 cases of asthma could be prevented from the LEZ extension in this scenario. These results were distributed heterogeneously across three socioeconomic (SES) groups, most noticeably with asthma cases as 230, 180, and 210 cases were avoided per 100,000 inhabitants in high, medium, and low SES groups, respectively. We found substantial economic benefits associated with LEZ, with estimates ranging from €0.76 billion to €2.36 billion for prevented deaths. The benefits associated with asthma reduction ranged from €2.3 million to €8.3 million. Discussion Conducting HIAs with a focus on equity will further inform policy makers of the impact of LEZ models on air pollution, health, and environmental justice. Developing these systematic methods and applying them to future LEZs and other air pollution policies will increase their effectiveness to reduce the burden of ambient air pollution on society and the environment.