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Air pollution has a great impact on health, representing one of the leading causes of death worldwide. Previous experimental and epidemiological studies suggested the role of pollutants as risk factors for cardiovascular diseases. For this reason, international guidelines included specific statements regarding the contribution of particulate matter exposure to increase the risk of these events. In this review, we summarise the main evidence concerning the mechanisms involved in the processes linking air pollutants to the development of cardiovascular diseases.

Published Mar 27, 2018

Vidale, S., & Campana, C. (2018). Ambient air pollution and cardiovascular diseases: From bench to bedside. European Journal of Preventive Cardiology, 25(8), 818–825. https://doi.org/10.1177/2047487318766638

Rationale: Nearly 60% of U.S. children live in counties with particulate matter less than or equal to 2.5 μm in aerodynamic diameter (PM2.5) concentrations above air quality standards. Understanding the relationship between ambient air pollution exposure and health outcomes informs actions to reduce exposure and disease risk.

Objectives: To evaluate the association between ambient PM2.5 levels and healthcare encounters for acute lower respiratory infection (ALRI).

Methods: Using an observational case-crossover design, subjects (n = 146,397) were studied if they had an ALRI diagnosis and resided on Utah’s Wasatch Front. PM2.5 air pollution concentrations were measured using community-based air quality monitors between 1999 and 2016. Odds ratios for ALRI healthcare encounters were calculated after stratification by ages 0–2, 3–17, and 18 or more years.

Measurements and Main Results: Approximately 77% (n = 112,467) of subjects were 0–2 years of age. The odds of ALRI encounter for these young children increased within 1 week of elevated PM2.5 and peaked after 3 weeks with a cumulative 28-day odds ratio of 1.15 per +10 μg/m3 (95% confidence interval, 1.12–1.19). ALRI encounters with diagnosed and laboratory-confirmed respiratory syncytial virus and influenza increased following elevated ambient PM2.5 levels. Similar elevated odds for ALRI were also observed for older children, although the number of events and precision of estimates were much lower.

Conclusions: In this large sample of urban/suburban patients, short-term exposure to elevated PM2.5 air pollution was associated with greater healthcare use for ALRI in young children, older children, and adults. Further exploration is needed of causal interactions between PM2.5 and ALRI.

Keywords: respiratory syncytial virus; influenza virus; bronchiolitis; bronchitis; PM2.5

Published Mar 22, 2018

Horne, B. D., Joy, E. A., Hofmann, M. G., Gesteland, P. H., Cannon, J. B., Lefler, J. S., . . . Pope, C. A. (2018). Short-term elevation of fine particulate matter air pollution and acute lower respiratory infection. American Journal of Respiratory and Critical Care Medicine, 198(6), 759-766. doi:10.1164/rccm.201709-1883oc

The adverse health effects of air pollution have long been recognised; however, there is less awareness that the majority of the morbidity and mortality caused by air pollution is due to its effects on the cardiovascular system. Evidence from epidemiological studies have demonstrated a strong association between air pollution and cardiovascular diseases including stroke. Although the relative risk is small at an individual level, the ubiquitous nature of exposure to air pollution means that the absolute risk at a population level is on a par with “traditional” risk factors for cardiovascular disease. Of particular concern are findings that the strength of this association is stronger in low and middle income countries where air pollution is projected to rise as a result of rapid industrialisation. The underlying biological mechanisms through which air pollutants exert their effect on the vasculature are still an area of intense discussion. A greater understanding of the effect size and mechanisms is necessary to develop effective strategies at individual and policy levels to mitigate the adverse cardiovascular effects of air pollution.

Published Jan 3, 2018

Lee, K. K., Miller, M. R., & Shah, A. S. V. (2018). Air pollution and stroke. Journal of Stroke, 20(1), 2–11. https://doi.org/10.5853/jos.2017.02894

Pollution is the largest environmental cause of disease and premature death in the world today. Diseases caused by pollution were responsible for an estimated 9 million premature deaths in 2015—16% of all deaths worldwide—three times more deaths than from AIDS, tuberculosis, and malaria combined and 15 times more than from all wars and other forms of violence. In the most severely affected countries, pollution-related disease is responsible for more than one death in four.

Published Jan 1, 2018

Landrigan, P. J., Fuller, R., Acosta, N. J. R., Adeyi, O., Arnold, R., Basu, N. (Nil), Baldé, A. B., Bertollini, R., Bose-O’Reilly, S., Boufford, J. I., Breysse, P. N., Chiles, T., Mahidol, C., Coll-Seck, A. M., Cropper, M. L., Fobil, J., Fuster, V., Greenstone, M., Haines, A., … Zhong, M. (2018). The Lancet Commission on pollution and health. The Lancet, 391(10119), 462–512. https://doi.org/10.1016/S0140-6736(17)32345-0

Elevated levels of fine particulate matter,2.5 mm in aerodynamic diameter (PM2.5) are associated with increased risk of cardiovascular outcomes and death, but their association with risk of CKD and ESRD is unknown. We linked the Environmental Protection Agency and the Department of Veterans Affairs databases to build an observational cohort of 2,482,737 United States veterans, and used survival models to evaluate the association of PM2.5 concentrations and risk of incident eGFR,60 ml/min per 1.73 m2, incident CKD, eGFR decline $30%, and ESRD over a median follow-up of 8.52 years. County-level exposure was defined at baseline as the annual average PM2.5 concentrations in 2004, and separately as time-varying where it was updated annually and as cohort participants moved. In analyses of baseline exposure (median, 11.8 [interquartile range, 10.1–13.7] mg/m3), a 10-mg/m3 increase in PM2.5 concentration was associated with increased risk of eGFR,60 ml/min per 1.73 m2 (hazard ratio [HR], 1.21; 95% confidence interval [95% CI], 1.14 to 1.29), CKD (HR, 1.27; 95% CI, 1.17 to 1.38), eGFR decline $30% (HR, 1.28; 95% CI, 1.18 to 1.39), and ESRD (HR, 1.26; 95% CI, 1.17 to 1.35). In time-varying analyses, a 10-mg/m3 increase in PM2.5 concentration was associated with similarly increased risk of eGFR,60 ml/min per 1.73 m2, CKD, eGFR decline $30%, and ESRD. Spline analyses showed a linear relationship between PM2.5 concentrations and risk of kidney outcomes. Exposure estimates derived from National Aeronautics and Space Administration satellite data yielded consistent results. Our findings demonstrate a significant association between exposure to PM2.5 and risk of incident CKD, eGFR decline, and ESRD.

Published Jan 1, 2018

Bowe, B., Xie, Y., Li, T., Yan, Y., Xian, H., & Al-Aly, Z. (2018). Particulate matter air pollution and the risk of incident CKD and progression to ESRD. Journal of the American Society of Nephrology, 29(1), 218–230. https://doi.org/10.1681/ASN.2017030253

With growing agreement that credible pathways to zero carbon electricity exist, many support the notion that widespread electrification of the transportation sector will be an essential strategy for meeting scientifically-based midcentury climate goals. While transit buses have a relatively small impact on greenhouse gas emissions, they have a larger impact on urban air quality, have commercially available in-service electric models, and have historically commercialized clean technologies that enabled deployment in the rest of the heavy duty vehicle sector. This thesis seeks to understand what factors hinder or enable transit agencies to go beyond initial pilots to largely or wholly electrify their fleets, with the goal of understanding potential policies and strategies that could accelerate such a transition, without inhibiting existing or expanded transit service that also plays a key role in reducing carbon emissions, in order to improve local air pollution and support accelerated electrification of trucks and other heavy duty vehicles. Using public transit fleets in California, Kentucky, and Massachusetts as case studies, this thesis utilizes quantitative total cost of ownership and well-to-wheels greenhouse gas and air pollutant emissions analysis, and analysis of qualitative interviews with transit agency representatives to investigate the barriers, drivers, and potential solutions that could hinder or enable an accelerated yet sustainable transition to an electrified bus fleet. A total cost of ownership analysis reveals that electric buses may already be more cost effective than diesel buses in many case study utility service areas primarily due to fuel and maintenance cost savings, but are sensitive to key parameters such as annual mileage, electricity tariffs that vary widely by location, fossil fuel costs, policy context, and anticipated maintenance savings, and that cost savings from electric buses are likely to increase over time primarily due to anticipated reductions in battery costs and a faster increase in fossil fuel prices than electricity prices. While multiple agencies interviewed in California were planning to fully electrify their fleets, primarily due to political pressure and internal leadership, outside California where less supportive policies exist, fewer agencies were planning to procure additional electric buses, primarily due to high first cost and undesirable tradeoffs with maintaining or expanding transit service levels. Interview respondents reported other substantial barriers as well, such as oversubscribed discretionary grant programs, charging infrastructure costs, electricity costs, additional operational complexity, and performance uncertainty and risk, suggesting a need for multiple complementary policies to overcome these barriers and ensure agencies can transition to a new technology without impacting service. Important interventions identified include pursuing favorable electricity tariffs and electric charging infrastructure incentives through regulatory changes, and further leveraging limited public funds such as the Volkswagen settlement to develop low cost financing approaches similar to those utilized in the clean energy sector that can pledge anticipated operating savings to afford the incremental upfront cost. A set of complementary policies is then recommended to accelerate bus fleet electrification in each case study context, in order to achieve carbon reduction and air quality improvements for low income, urban communities without impacting transit service levels, and to help lead the way for the transition of other heavy duty fleets.

Published Jan 1, 2018

Blynn, K. (2018). Accelerating Bus Electrification: Enabling a sustainable transition to low carbon transportation systems. Massachusetts Institute of Technology. https://dspace.mit.edu/handle/1721.1/115600

Fossil-fuel combustion by-products are the world’s most significant threat to children’s health and future and are major contributors to global inequality and environmental injustice. The emissions include a myriad of toxic air pollutants and carbon dioxide (CO2), which is the most important human-produced climate-altering greenhouse gas. Synergies between air pollution and climate change can magnify the harm to children. Impacts include impairment of cognitive and behavioral development, respiratory illness, and other chronic diseases—all of which may be “seeded“ in utero and affect health and functioning immediately and over the life course. By impairing children’s health, ability to learn, and potential to contribute to society, pollution and climate change cause children to become less resilient and the communities they live in to become less equitable. The developing fetus and young child are disproportionately affected by these exposures because of their immature defense mechanisms and rapid development, especially those in low- and middle-income countries where poverty and lack of resources compound the effects. No country is spared, however: even high-income countries, especially low-income communities and communities of color within them, are experiencing impacts of fossil fuel-related pollution, climate change and resultant widening inequality and environmental injustice. Global pediatric health is at a tipping point, with catastrophic consequences in the absence of bold action. Fortunately, technologies and interventions are at hand to reduce and prevent pollution and climate change, with large economic benefits documented or predicted. All cultures and communities share a concern for the health and well-being of present and future children: this shared value provides a politically powerful lever for action. The purpose of this commentary is to briefly review the data on the health impacts of fossil-fuel pollution, highlighting the neurodevelopmental impacts, and to briefly describe available means to achieve a low-carbon economy, and some examples of interventions that have benefited health and the economy.

Published Dec 23, 2017

Perera, F. (2017). Pollution from Fossil-Fuel Combustion is the Leading Environmental Threat to Global Pediatric Health and Equity: Solutions Exist. International Journal of Environmental Research and Public Health 2018, Vol. 15, Page 16, 15(1), 16. https://doi.org/10.3390/IJERPH15010016

Read bios and background on this film covering the history of Old Smokey, the former incinerator, which operated from 1925 to 1970, and its environmental health impact on the West Grove community.

Published Nov 14, 2017

Law, U. of M. S. of. (2017). “Old Smokey: A Community History.” University of Miami School of Law. https://issuu.com/miamilaw/docs/ceps_oral_20history_20film_20projec

Electrification has been rapidly promoted to transform the energy source for public transit buses. Among all electric technologies penetrating the public bus fleet, battery electric buses (BEBs) dominates the market. Nevertheless, real-world energy consumption (EC) is of great concern, since BEBs are often used under congested conditions that may affect their energy and environmental benefits. This study proposes an operating mode binning method to assess on-road EC and well-to-wheel (WTW) air pollutants emissions of BEBs under complex real-world usage patterns. Second-by-second EC and operating data of two BEBs demonstrated in Macao, China is adopted to establish the EC profiles under each micro modes. Results show that EC value would be below zero in certain operation modes with negative vehicle specific power values, which suggests the regenerative brake system is effectively functioning under deceleration conditions. Average EC are estimated to be 1.7 to 4.1 kWh km−1 for BEB12 and 1.2 to 2.9 kWh km−1 for BEB10 (i.e., vehicle length of 12 m and 10 m), respectively, under all operating conditions (i.e., 18 various patterns) by average speed, loading mass and air conditioner usage. The large variation in real-world EC would proportionally affect WTW emissions of carbon dioxide (CO2) and air pollutants from BEBs. When deployed in Macao where non-fossil electricity is relatively abundant, BEB can significantly reduce WTW emissions of nitrogen oxides (NOX) and volatile organic compounds (VOC) by 60%–80%, along with considerable reductions of 10%–40% for CO2 and fine particulate matters (PM2.5). Further, the benefits related to WTW CO2 and PM2.5 emissions would not exist if BEBs are deployed in coal power-rich regions. Our measurement results and WTW emission suggests that current fuel economy testing procedure of BEB should be modified to better inform customers and policy-makers of their real-world performance and benefits.

Published Oct 17, 2017

He, X., Zhang, S., Ke, W., Zheng, Y., Zhou, B., Liang, X., & Wu, Y. (2018). Energy consumption and well-to-wheels air pollutant emissions of battery electric buses under complex operating conditions and implications on fleet electrification. Journal of Cleaner Production, 171, 714–722. https://doi.org/10.1016/j.jclepro.2017.10.017

A child's exposure to environmental pollutants can have life-long health effects. Thus it is critical to understand the potential exposure pathways. In this paper, we examine the increase in ambient PM2.5 concentrations at schools from private vehicle use for dropping children off at school. In North America, students are commonly driven to school in a private vehicle. Additionally, students walk or cycle, or take a school bus. Our vehicle surveys recorded between 23 and 116 personal vehicles at 25 schools, where enrolment ranged from 160 to 765 students. We fit a linear regression model to predict the number of vehicles at schools we did not observe within our study area, which explained 57% of the variation in our surveys. A microsimulation traffic model was created for each of the 86 schools we studied. Outputs from the traffic model were used to determine the emissions generated at each school. PM2.5 emissions varied from 0.14 to 6.38 g. Lastly, we dispersed the emissions produced by private vehicles dropping off students, which are emissions generated by unnecessary trips because students further than walking distance are provided transportation by the school board. At the drop-off location in front of the school, we found ambient concentration increases of at least 5 μg/m3, 10 μg/m3, 25 μg/m3 and 50 μg/m3 during 16.8%, 7.6%, 2.0% and 0.5% of the mornings, respectively. This research was conducted in a medium-sized North American city and should allow transferability to similar cities. We conclude that the use of private vehicles can significantly increase local concentrations, regardless of background conditions.

Published Sep 1, 2017

Adams, M. D., & Requia, W. J. (2017). How private vehicle use increases ambient air pollution concentrations at schools during the morning drop-off of children. Atmospheric Environment, 165, 264–273. https://doi.org/10.1016/j.atmosenv.2017.06.046