Jonathan Alan Patz

Air pollution exposure poses health and economic burdens, but most assessments of air pollution in the United States do not account for known variation in costs of hospital admissions and emergency department (ED) visits by race/ethnicity or region, nor do they include ambulatory care and other health-related costs. Given that medical cost data are used regularly in policy and regulatory analyses of air pollution, it is important that these data be finely resolved and comprehensive. We estimate hospital admission and ED visit costs by region, race/ethnicity, and payer type for cardiovascular, respiratory, and neurological health outcomes associated with fine particulate matter (PM _2.5 ) exposure that are included in the Environmental Benefits Mapping and Analysis Program–Community Edition. We also determine additional costs associated with outpatient surgeries, home health care, and prescribed medicines. We then apply these cost data to PM _2.5 air quality improvement scenarios to assess their effect on monetized benefit totals. Regional hospital admission and ED visit costs differ from the national average by as much as −34% to +65%. Asian Americans incur the highest per-event costs for most outcomes. White and Black Americans generally incur below-average per-event costs for hospital admissions, and Black and Hispanic Americans incur below-average per-event costs for ED visits. Additional costs greatly increase the total cost of medical events for cardiovascular disease outcomes and hospital admissions for Parkinson’s disease and respiratory diseases (ages ⩽ 18). When stratifying medical costs by race/ethnicity and region and including additional costs, monetized benefits increase by 64% under the revised National Ambient Air Quality Standard for annual PM _2.5 exposure. The effect of cost stratification is less pronounced in scenarios in which PM _2.5 reductions are more widespread. We recommend that stratified health cost data be considered for use in policy and regulatory analysis, particularly in work considering health equity implications of air pollution exposure.

British colonial urban planners in Kampala, Uganda, designed segregated neighborhoods for Europeans, Asians, and Africans, under the colonial public health guidance. No studies have investigated how these historical urban design decisions relate to modern air pollution exposure disparities in African cities. We sought to determine whether colonial‐era racial segregation of settlements in Kampala, Uganda, influences modern intra‐urban spatial distribution of ambient fine particulate matter (PM _2.5 ) concentrations in the city. Using an urban network of 52 low‐cost PM sensors, we estimated monthly PM _2.5 concentrations across Kampala from 2021 to 2022. We manually digitized and correlated 2020 satellite imagery and street maps of the three historical boundaries of European/Asian and African settlements from a 1951 map. Extreme gradient boosting trees, random forest models, and empirical Bayes kriging were used to predict gridded monthly PM _2.5 averages for the study area. We used non‐parametric statistical tests and multivariable linear regression to compare monthly PM _2.5 levels between European/Asian and African settlements. We observed significantly higher median monthly PM _2.5 concentration in African settlements (median = 33.0 μg/m ³ [interquartile range = 28.2, 39.3]) compared to European/Asian areas (median = 28.8 μg/m ³ [IQR = 25.2, 33.5]). In crude linear regression models, African settlements had a higher PM _2.5 concentration by 9.2% (95% CI: 6.4, 18.5). African settlements showed greater seasonal PM _2.5 variations and higher current social vulnerability. This study highlights the enduring influence of colonial urban planning on today's environmental health inequalities.

Food waste is a major contributor to climate change, responsible for about one-third of all human-induced greenhouse gas emissions. Despite widespread sustainability efforts, institutions of higher education are not immune from generating substantial waste. Universities also present unique opportunities to both study and intervene in consumer food waste in a controlled environment. In this scoping review, we screened 1294 articles, finding just 27 studies that directly measured food waste changes associated with strategies implemented in university dining facilities. Results indicate five primary behavioral and educational intervention methodologies employed. Environmental interventions, particularly tray removal, were among the most effective strategies, resulting in food waste reductions of 20% to 32% by weight. Passive education efforts, such as displaying informational posters, had mixed results, while financial incentives resulted in food waste reductions but may unintentionally encourage overconsumption. Combination interventions resulted in greater impact than individual interventions, though implementation challenges remain. Inconsistent waste measurement methods across studies, including whether to include both liquid and unavoidable food waste, complicate cross-study comparisons. Short intervention durations also limit insight into long-term effectiveness. While student support for sustainability initiatives is widespread, standardized auditing methods and longer-term research are needed to develop realistic and sustainable interventions that effectively reduce consumer food waste in university settings.

Background Rennes, a midsize city in France, features many opportunities for active travel. City officials seek to increase walking and cycling by 2030 to improve public health. Physical inactivity, a leading risk factor for premature mortality around the globe, has been shown to be associated with many chronic diseases including heart disease, type 2 diabetes, and cancer. Methods Using the 2018 household travel survey of Rennes residents, we apply the Health-Oriented Transportation statistical model to assess health impacts associated with population-level rates of walking and cycling. We consider two proposed mobility and climate objectives which outline sustainable transportation goals by 2030. These include a shift in transportation mode share to increase walking and cycling trips, as well as a broad reduction in vehicle miles traveled (VMT) across the metropolitan area. Results Our regression analysis demonstrated that factors of household car access and inner-city residency were predictors of prevalence (observed one-day proportion engaging in walking or cycling), participation (weekly proportion), and intensity (mean individual physical activity achieved through walking/cycling) of active travel. Age and education were additionally associated with prevalence. The 2030 mobility objective (mode share: 9% cycle, 35% walk) was associated with a reduction of 1,051 DALYs (disability-adjusted life-years), translating to $73 million USD ($23-$177) in averted costs. The climate objective (10% reduction in VMT) was associated with a reduction of 369 DALYs when replaced entirely by walking and 714 DALYs with cycling, translating to $26 million ($8-$62) and $50 million ($15-$121) saved, respectively. Conclusions Rennes residents experience high participation in active travel, particularly those in the inner city. If residents achieve the city’s active travel goals for 2030, there is potential for a large reduction in health burden and subsequent costs. Reaching these goals may require significant investment in transportation programming and infrastructure to improve active travel opportunities.

Background The prevalence of chronic disease in the US adult population varies across socioeconomic groups in the USA where approximately six in 10 adults have a chronic condition. Walking or cycling reduces the risk to many of these diseases and is influenced by the built environment, accessibility, and safety. Methods We performed multivariate logistic and linear regression on the Health-Oriented Transportation model parameters using the 2009 and 2017 US National Household Transportation surveys, restricted to adults in major metropolitan areas. Model covariates included socioeconomic and environmental characteristics. Results Using odds ratios (OR) adjusted for model covariates, we observe several significant variables in 2009 and 2017. Residents of households with no cars were more likely to walk or cycle than those with two cars; OR=5.4 (4.8, 6.0). Residents of households in a census block with population density greater than 2,5000 persons/square mile were more likely to walk or cycle than those with a population density of 2000–3999; OR=2.6 (2.3, 2.8). Individuals with a graduate or professional degree were more likely to walk or cycle than those with a high school degree; OR=2.1 (1.9, 2.2). Individuals that self-report as Black or African American, or Asian are less likely to walk or cycle than White; OR=0.60 (0.56, 0.66), OR=0.70 (0.65, 0.75). The proportional increase in all-cause mortality from estimated reductions in physical activity for African American, Asian, and Hispanic populations were 1.0%, 0.7%, 0.8%, respectively. Conclusions Access to automobiles and the surrounding population density are primary factors in the decision to walk or cycle. After adjusting for these and other factors, members of low-income, low-education, Black or African American, and Asian populations in US metropolitan areas are less likely to walk or cycle than high-income, high-education, or White populations and the discrepancy in physical activity is likely to contribute to health inequity.

Background Rennes, a midsize city in France, features many opportunities for active travel. City officials seek to increase walking and cycling by 2030 to improve public health. Physical inactivity, a leading risk factor for premature mortality around the globe, has been shown to be associated with many chronic diseases including heart disease, type 2 diabetes, and cancer. Methods Using the 2018 household travel survey of Rennes residents, we apply the Health-Oriented Transportation statistical model to assess health impacts associated with population-level rates of walking and cycling. We consider two proposed mobility and climate objectives which outline sustainable transportation goals by 2030. These include a shift in transportation mode share to increase walking and cycling trips, as well as a broad reduction in vehicle miles traveled (VMT) across the metropolitan area. Results Our regression analysis demonstrated that factors of household car access and inner-city residency were predictors of prevalence (observed one-day proportion engaging in walking or cycling), participation (weekly proportion), and intensity (mean individual physical activity achieved through walking/cycling) of active travel. Age and education were additionally associated with prevalence. The 2030 mobility objective (mode share: 9% cycle, 35% walk) was associated with a reduction of 1,051 DALYs (disability-adjusted life-years), translating to $73 million USD ($23-$177) in averted costs. The climate objective (10% reduction in VMT) was associated with a reduction of 369 DALYs when replaced entirely by walking and 714 DALYs with cycling, translating to $26 million ($8-$62) and $50 million ($15-$121) saved, respectively. Conclusions Rennes residents experience high participation in active travel, particularly those in the inner city. If residents achieve the city’s active travel goals for 2030, there is potential for a large reduction in health burden and subsequent costs. Reaching these goals may require significant investment in transportation programming and infrastructure to improve active travel opportunities.

Background: The prevalence of chronic disease in the US adult population varies across socioeconomic groups in the USA where approximately six in 10 adults have a chronic condition. Walking or cycling reduces the risk to many of these diseases and is influenced by the built environment, accessibility, and safety. Methods: We performed multivariate logistic and linear regression on the Health-Oriented Transportation model parameters using the 2009 and 2017 US National Household Transportation surveys, restricted to adults in major metropolitan areas. Model covariates included socioeconomic and environmental characteristics. Results: Using odds ratios (OR) adjusted for model covariates, we observe several significant variables in 2009 and 2017. Residents of households with no cars were more likely to walk or cycle than those with two cars; OR=5.4 (4.8, 6.0). Residents of households in a census block with population density greater than 2,5000 persons/square mile were more likely to walk or cycle than those with a population density of 2000–3999; OR=2.6 (2.3, 2.8). Individuals with a graduate or professional degree were more likely to walk or cycle than those with a high school degree; OR=2.1 (1.9, 2.2). Individuals that self-report as Black or African American, or Asian are less likely to walk or cycle than White; OR=0.60 (0.56, 0.66), OR=0.70 (0.65, 0.75). The proportional increase in all-cause mortality from estimated reductions in physical activity for African American, Asian, and Hispanic populations were 1.0%, 0.7%, 0.8%, respectively. Conclusions: Access to automobiles and the surrounding population density are primary factors in the decision to walk or cycle. After adjusting for these and other factors, members of low-income, low-education, Black or African American, and Asian populations in US metropolitan areas are less likely to walk or cycle than high-income, high-education, or White populations and the discrepancy in physical activity is likely to contribute to health inequity.

Clean energy policy can provide substantial health benefits through improved air quality. As ambitious clean energy proposals are increasingly considered and adopted across the United States (US), quantifying the benefits of removal of such large air pollution emissions sources is crucial to understanding potential societal impacts of such policy. In this study, we estimate health benefits resulting from the elimination of emissions of fine particulate matter (PM_2.5), sulfur dioxide, and nitrogen oxides from the electric power, transportation, building, and industrial sectors in the contiguous US. We use EPA's CO‐Benefits Risk Assessment screening tool to estimate health benefits resulting from the removal of PM_2.5‐related emissions from these energy‐related sectors. We find that nationwide efforts to eliminate energy‐related emissions could prevent 53,200 (95% CI: 46,900–59,400) premature deaths each year and provide $608 billion ($537–$678 billion) in benefits from avoided PM_2.5‐related illness and death. We also find that an average of 69% (range: 32%–95%) of the health benefits from emissions removal remain in the emitting region. Our study provides an indication of the potential scale and distribution of public health benefits that could result from ambitious regional and nationwide clean energy and climate mitigation policy.

The climate crisis threatens to exacerbate numerous climate-sensitive health risks, including heatwave mortality, malnutrition from reduced crop yields, water- and vector-borne infectious diseases, and respiratory illness from smog, ozone, allergenic pollen, and wildfires. Recent reports from the Intergovernmental Panel on Climate Change stress the urgent need for action to mitigate climate change, underscoring the need for more scientific assessment of the benefits of climate action for health and wellbeing. Project Drawdown has analyzed more than 80 solutions to address climate change, building on existing technologies and practices, that could be scaled to collectively limit warming to between 1.5° and 2 °C above preindustrial levels. The solutions span nine major sectors and are aggregated into three groups: reducing the sources of emissions, maintaining and enhancing carbon sinks, and addressing social inequities. Here we present an overview of how climate solutions in these three areas can benefit human health through improved air quality, increased physical activity, healthier diets, reduced risk of infectious disease, and improved sexual and reproductive health, and universal education. We find that the health benefits of a low-carbon society are more substantial and more numerous than previously realized and should be central to policies addressing climate change. Much of the existing literature focuses on health effects in high-income countries, however, and more research is needed on health and equity implications of climate solutions, especially in the Global South. We conclude that adding the myriad health benefits across multiple climate change solutions can likely add impetus to move climate policies faster and further.