California's early transition to electric vehicles: Observed health and air quality co-benefits

Emerging evidence for the impact of Electric Vehicle sales on childhood asthma: Can ZEV mandates help?

Growing epidemiological studies indicate a significant fraction of asthma cases can be attributed to traffic-related air pollution (TRAP). Zero emission vehicle (ZEV) mandates - one of the most forward-looking climate policies in the United States - aim to reduce TRAP by mandating automakers to sell a certain fraction of Electric Vehicles (EVs) annually; however, their public health benefits are largely unknown. We conduct the screening step of the health impact assessment (HIA) of real-world EV sales to estimate the impact of ZEV mandates in reducing childhood asthma. Using publicly available US state and national datasets, we isolate the burden of childhood asthma attributable to TRAP from 2013 to 2019 and examine the influence of EV and non-EV vehicle sales and fleets on asthma incidence and prevalence using a generalized linear mixed model. Our analyses indicate that new EV sales have reduced asthma, with one asthma case prevented for every 264 (95% CI: 113-401) new EVs on the road. The rise of new childhood asthma cases from new car sales can be prevented when non-EV sales are replaced with EV sales at an annual market share of 21.4% (7.1-41.6%). Extending our analysis to the entire vehicle fleet, we project that when EVs reach 53.0% (35.5%-76.9%), childhood asthma due to tailpipe emissions can be eradicated completely. Screening results conclude that ZEV mandates implemented over the past decade are already exhibiting measurable public health benefits, suggesting that a broader adoption could significantly reduce the asthma burden, thus we recommend a full HIA for ZEV mandates to fully assess their potential.

Remarkable results of energy consumption and CO2 emissions for gasoline and electric powered vehicle

Increasing concerns about climate change and efforts on reducing reliance on fossil fuels have led to research on electric vehicles for sustainable solutions to increasing energy demands. This study comprehensively analyzes the impact of power plant emissions on the adoption of electric vehicles in relation to air pollution. The main pollutants emitted by power plants and the potential change in emissions with the deployment of electric vehicles are assessed. Energy consumption of the vehicles was calculated. A gasoline-powered and an electric vehicle are modelled in MATLAB Simulink software. The theoretical model results of the main pollutants are compared with the power plant emissions to analyze the effect on major pollutants. This investigation aims to identify the potential CO2 emission and power requirement by transitioning to electric vehicles. Results show that energy consumption and CO2 emissions can be 111% and 82% higher than GPVs depending on the electricity generation technologies.

Fifteen Pathways between Electric Vehicles and Public Health: A Transportation-Health Conceptual Framework

The health impact of electric vehicles (EVs) is complex and multifaceted, encompassing reductions in air pollutants, improvements in road safety, and implications for social equity. However, existing studies often provide fragmented insights, lacking a unified framework to comprehensively assess these public health implications. This paper develops a comprehensive framework to summarize the health outcomes of EVs in urban areas, where the health impacts are more pronounced due to higher levels of traffic congestion and air pollution. Building on previous conceptual work that identified pathways linking general transportation and health, our model illustrates how the characteristics of EVs influence public health through various pathways compared to traditional transportation systems. Additionally, we address socioeconomic factors that introduce variability in EV-related health outcomes, emphasizing the need to consider potential health disparities in policy and intervention development. This comprehensive approach aims to inform holistic policies that account for the complex interplay between transportation, environment, and public health.

Impacts of the Chengdu 2021 world university games on NO2 pollution: Implications for urban vehicle electrification promotion

Emissions of nitrogen oxides (NOx) are a dominant contributor to ambient nitrogen dioxide (NO2) concentrations, but the quantitative relationship between them at an intracity scale remains elusive. The Chengdu 2021 FISU World University Games (July 22 to August 10, 2023) was the first world-class multisport event in China after the COVID-19 pandemic which led to a substantial decline in NOx emissions in Chengdu. This study evaluated the impact of variations in NOx emissions on NO2 concentrations at a fine spatiotemporal scale by leveraging this event-driven experiment. Based on ground-based and satellite observations, we developed a data-driven approach to estimate full-coverage hourly NO2 concentrations at 1 km resolution. Then, a random-forest-based meteorological normalization method was applied to decouple the impact of meteorological conditions on NO2 concentrations for every grid cell, the resulting data were then compared with the timely bottom-up NOx emissions. The SHapley-Additive-exPlanation (SHAP) method was employed to delineate the individual contributions of meteorological factors and various emission sources to the changes in NO2 concentrations. According to the full-coverage meteorologically normalized NO2 concentrations, a decrease in NOx emissions and favorable meteorological conditions accounted for 80 % and 20 % of the NO2 reduction, respectively, across Chengdu city during the control period. Within the strict control zone, a 30 % decrease in the meteorologically normalized NO2 concentrations was observed during the control period. The normalized NO2 concentrations demonstrated a strong correlation with NOx emissions (R = 0.96). Based on the SHAP analysis, traffic emissions accounted for 73 % of the reduction in NO2 concentrations, underscoring the significance of traffic control measures in improving air quality in urban areas. This study provides insights into the relationship between NO2 concentrations and NOx emissions using real-world data, which implies the substantial benefits of vehicle electrification for sustainable urban development.

The impact of hydrogen fuel cell heavy-duty trucks purchase subsidies on air quality

The pollutant emissions of diesel-powered heavy-duty trucks (HDTs) seriously damage the air quality. The promotion of hydrogen fuel cell HDTs through purchase subsidy policy to reduce emissions has become an important approach to control air pollution. This study focuses on the impact of hydrogen fuel cell HDT purchase subsidies on air quality in the context of China, covering the panel data of 31 Chinese cities from 2014 to 2021 and applying a two-way fixed effects model to analyze the contribution of purchase subsidies and hydrogen refueling station construction subsidies to air quality. Results show that (1) the increase in purchase subsidies could improve the air quality by around 6.1% and there is a lag effect. (2) Purchase subsidies make a larger contribution to air quality compared with construction subsidies. (3) Purchase subsidies can improve air quality by reducing carbon emissions in transport industry. In sight of these results, policy makers should emphasize the implementation of purchase subsidies and hydrogen refueling station construction subsidies and stimulate manufacturers to improve the performance of hydrogen fuel cell so as to contribute more to the environment.

Electric vehicles and health: A scoping review

BACKGROUND

The health impacts of the rapid transition to the use of electric vehicles are largely unexplored. We completed a scoping review to assess the state of the evidence on use of battery electric and hybrid electric vehicles and health.

METHODS

We conducted a literature search of MEDLINE, Embase, Global Health, CINAHL, Scopus, and Environmental Science Collection databases for articles published January 1990 to January 2024. We included articles if they presented observed or modeled data on the association between battery electric or hybrid electric cars, trucks, or buses and health-related outcomes. We abstracted data and summarized results.

RESULTS

Out of 897 reviewed articles, 52 met our inclusion criteria. The majority of included articles examined transitions to the use of electric vehicles (n = 49, 94%), with fewer studies examining hybrid electric vehicles (n = 11, 21%) or plug-in hybrid electric vehicles (n = 8, 15%). The most common outcomes examined were premature death (n = 41, 79%) and monetized health outcomes such as medical expenditures (n = 33, 63%). We identified only one observational study on the impact of electric vehicles on health; all other studies reported modeled data. Almost every study (n = 51, 98%) reported some evidence of a positive health impact of transitioning to electric or hybrid electric vehicles, although magnitudes of association varied. There was a paucity of information on the environmental justice implications of vehicle transitions.

CONCLUSIONS

The results of the current literature on electric vehicles and health suggest an overall positive health impact of transitioning to electric vehicles. Additional observational studies would help expand our understanding of the real-world health effects of electric vehicles. Future research focused on the environmental justice implications of vehicle fleet transitions could provide additional information about the extent to which the health benefits occur equitably across populations.

Air quality and health co-benefits of vehicle electrification and emission controls in the most populated United States urban hubs: Insights from New York, Los Angeles, Chicago, and Houston

Transitioning to electric vehicles (EVs) is a prominent strategy for reducing greenhouse gas emissions. However, given the complexity of atmospheric chemistry, the nuanced implications on air quality are yet to be fully understood. Our study delved into changes in PM2.5, ozone, and their associated precursors in major US urban areas, considering various electrification and mitigation scenarios. In the full electrification (FullE) scenario, PM2.5 reduction peaked at values between 0.34 and 2.29 μg.m-3 across distinct regions. Yet, certain areas in eastern Los Angeles exhibited a surprising uptick in PM2.5, reaching as much as 0.67 μg.m-3. This phenomenon was linked to a surge in secondary organic aerosols (SOAs), resulting from shifting NOx/VOCs (volatile organic compounds) dynamics and a spike in hydroxyl radical (OH) concentrations. The FullE scenario ushered in marked reductions in both NOx and maximum daily average 8-h (MDA8) ozone concentrations, with maximum levels ranging from 14.00 to 32.34 ppb and 2.58-9.58 ppb, respectively. However, certain instances revealed growths in MDA8 ozone concentrations, underscoring the intricacies of air quality management. From a health perspective, in the FullE scenario, New York, Chicago, and Houston stand to potentially avert 796, 328, and 157 premature deaths/month, respectively. Los Angeles could prevent 104 premature deaths/month in the HighE-BL scenario, representing a 29 % EV share for light-duty vehicles. However, the FullE scenario led to a rise in mortality in Los Angeles due to increased PM2.5 and MDA8 ozone levels. Economically, the FullE scenario projects health benefits amounting to 51-249 million $/day for New York, Chicago, and Houston. In contrast, Los Angeles may face economic downturns of up to 18 million $/day. In conclusion, while EV integration has the potential to improve urban air quality, offering substantial health and economic advantages, challenges persist. Our results emphasize the pivotal role of VOCs management, providing policymakers with insights for adaptable and efficient measures.

Updates in Air Pollution: Current Research and Future Challenges

Background

The United Nations has declared that humans have a right to clean air. Despite this, many deaths and disability-adjusted life years are attributed to air pollution exposure each year. We face both challenges to air quality and opportunities to improve, but several areas need to be addressed with urgency.

Objective

This paper summarises the recent research presented at the Pacific Basin Consortium for Environment and Health Symposium and focuses on three key areas of air pollution that are important to human health and require more research.

Findings and conclusion

Indoor spaces are commonly places of exposure to poor air quality and are difficult to monitor and regulate. Global climate change risks worsening air quality in a bi-directional fashion. The rising use of electric vehicles may offer opportunities to improve air quality, but it also presents new challenges. Government policies and initiatives could lead to improved air and environmental justice. Several populations, such as older people and children, face increased harm from air pollution and should become priority groups for action.

California's zero-emission vehicle adoption brings air quality benefits yet equity gaps persist

Zero-emission vehicle (ZEV) adoption is a key climate mitigation tool, but its environmental justice implications remain unclear. Here, we quantify ZEV adoption at the census tract level in California from 2015 to 2020 and project it to 2035 when all new passenger vehicles sold are expected to be ZEVs. We then apply an integrated traffic model together with a dispersion model to simulate air quality changes near roads in the Greater Los Angeles. We found that per capita ZEV ownership in non-disadvantaged communities (non-DACs) as defined by the state of California is 3.8 times of that in DACs. Racial and ethnic minorities owned fewer ZEVs regardless of DAC designation. While DAC residents receive 40% more pollutant reduction than non-DACs due to intercommunity ZEV trips in 2020, they remain disproportionately exposed to higher levels of traffic-related air pollution. With more ZEVs in 2035, the exposure disparity narrows. However, to further reduce disparities, the focus must include trucks, emphasizing the need for targeted ZEV policies that address persistent pollution burdens among DAC and racial and ethnic minority residents.

Health-based strategies for overcoming barriers to climate change adaptation and mitigation

Climate change poses an unequivocal threat to the respiratory health of current and future generations. Human activities-largely through the release of greenhouse gases-are driving rising global temperatures. Without a concerted effort to mitigate greenhouse gas emissions or adapt to the effects of a changing climate, each increment of warming increases the risk of climate hazards (eg, heat waves, floods, and droughts) that that can adversely affect allergy and immunologic diseases. For instance, wildfires, which release large quantities of particulate matter with a diameter of less than 2.5 μm (an air pollutant), occur with greater intensity, frequency, and duration in a hotter climate. This increases the risk of associated respiratory outcomes such as allergy and asthma. Fortunately, many mitigation and adaptation strategies can be applied to limit the impacts of global warming. Adaptation strategies, ranging from promotions of behavioral changes to infrastructural improvements, have been effectively deployed to increase resilience and alleviate adverse health effects. Mitigation strategies aimed at reducing greenhouse gas emissions can not only address the problem at the source but also provide numerous direct health cobenefits. Although it is possible to limit the impacts of climate change, urgent and sustained action must be taken now. The health and scientific community can play a key role in promoting and implementing climate action to ensure a more sustainable and healthy future.

Sports Utility Vehicles: A Public Health Model of Their Climate and Air Pollution Impacts in the United Kingdom

The emission benefits of shifting towards battery electric vehicles have so far been hampered by a trend towards sports utility vehicles (SUVs). This study assesses the current and future emissions from SUVs and their potential impact on public health and climate targets. We modelled five scenarios of varying SUV sales and electrification rates, and projected associated carbon dioxide (CO2) and nitrogen oxide (NOx) emissions. Multiple linear regression was used to determine the relationship between vehicle characteristics and emissions. Cumulative CO2 emissions were valued using the social cost of carbon approach. Life table analyses were used to project and value life years saved from NOx emission reductions. Larger SUVs were disproportionately high emitters of CO2 and NOx. Replacing these with small SUVs achieved significant benefits, saving 702 MtCO2e by 2050 and 1.8 million life years from NO2 reductions. The largest benefits were achieved when combined with electrification, saving 1181 MtCO2e and gaining 3.7 million life years, with a societal value in the range of GBP 10-100s billion(s). Downsizing SUVs could be associated with major public health benefits from reduced CO2 and NOx emissions, in addition to the benefits of electrification. This could be achieved by demand-side mass-based vehicle taxation and supply-side changes to regulations, by tying emission limits to a vehicle's footprint rather than its mass.