Dirt in the Air
Airborne Lead Exposure and Childhood Cognition: The Environmental Influences on Child Health Outcomes (ECHO) Cohort (2003–2022)
Lisa Gatzke-Kopp et al.
American Journal of Public Health, March 2024, Pages 309-318
Methods: Residential addresses of children (< 5 years) were spatially joined to the Risk-Screening Environmental Indicators model of relative airborne lead toxicity. Cognitive outcomes for children younger than 8 years were available for 1629 children with IQ data and 1476 with measures of executive function (EF; inhibitory control, cognitive flexibility). We used generalized linear models using generalized estimating equations to examine the associations of lead, scaled by interquartile range (IQR), accounting for individual- and area-level confounders.
Results: An IQR increase in airborne lead was associated with a 0.74-point lower mean IQ score (b = −0.74; 95% confidence interval = −1.00, −0.48). The association between lead and EF was nonlinear and was modeled with a knot at the 97.5th percentile of lead in our sample. Lead was significantly associated with lower mean inhibitory control but not with cognitive flexibility. This effect was stronger among males for both IQ and inhibitory control.
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Optimal Urban Transportation Policy: Evidence from Chicago
Milena Almagro et al.
NBER Working Paper, March 2024
Abstract:
We characterize optimal urban transportation policies in the presence of congestion and environmental externalities and evaluate their welfare and distributional effects. We present a framework of a municipal government that implements different transportation equilibria through its choice of public transit policies -- prices and frequencies -- as well as road pricing. The government faces a budget constraint that introduces monopoly-like distortions. We apply this framework to Chicago, for which we construct a new dataset that comprehensively captures transportation choices. We find that road pricing alone leads to large welfare gains by reducing externalities, but at the expense of consumers (travelers), whose surplus falls even if road pricing revenues are fully rebated. The largest losses are borne by middle income consumers, who are most reliant on cars. We find that the optimal price of public transit is close to zero and goes along with a reduction in the frequency of buses and an increase in the frequency of trains. Combining these transit policies with road pricing eliminates budget constraints. This allows the government to implement higher transit frequencies and even lower prices, in which case consumer surplus increases after rebates.
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Higher air pollution in wealthy districts of most low- and middle-income countries
Patrick Behrer & Sam Heft-Neal
Nature Sustainability, February 2024, Pages 203–212
Abstract:
Air pollution is a major threat to health and the dangers are particularly acute in low- and middle-income countries where levels of exposure tend to be high and adaptation resources are often limited. However, little is known about how the burden of pollution is spread across different income groups within these countries. Understanding who is impacted by air pollution is important for designing equitable policy solutions. In this study, we used data providing high-resolution wealth estimates for more than 100 countries, combined with high-resolution estimates of air pollution, to estimate how wealth is correlated with ambient air pollution in low- and middle-income countries around the world. We found that within countries, on average, air pollution is positively correlated with wealth, but the relationship is highly heterogeneous across countries. Countries with primarily anthropogenic sources of air pollution seem to have the strongest positive correlations between pollution and wealth. The fact that air pollution and wealth are both disproportionately high in urban areas where economic activity is largely concentrated seems to drive this relationship. The spatial correlation between pollution and areas of economic opportunity highlights the urgent need to develop policies that reduce air pollution to promote more equitable economic growth.
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Fresh Air Eases Work -- the Effect of Air Quality on Individual Investor Activity
Steffen Meyer & Michaela Pagel
Review of Finance, forthcoming
Abstract:
This paper shows that contemporaneous and lagged air pollution significantly negatively affects the likelihood of German individual investors logging in and trading in their brokerage accounts, using intra-day data and controlling for investor-, weather-, traffic-, and market-specific factors. A one standard deviation increase in air pollution leads to a 1.3% reduction in the probability of logging in, which is larger than the response to a one standard deviation increase in sunshine. We argue that changes in air pollution affect productivity in cognitively demanding tasks, such as trading. Our results are robust to macroeconomic productivity shocks, non-linearities, or measurement errors.
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Driving Under the Influence of Allergies: The Effect of Seasonal Pollen on Traffic Fatalities
Shooshan Danagoulian & Monica Deza
NBER Working Paper, March 2024
Abstract:
Traffic fatalities are the leading cause of mortality in the United States despite being preventable. While several policies have been introduced to improve traffic safety and their effects have been well documented, the role of transitory health shocks or situational factors at explaining variations in fatal traffic accidents has been understudied. Exploring daily variation in city-specific pollen counts, this study finds novel evidence that traffic fatalities increase on days in which the local pollen count are particularly high. We find that the effects are present in accidents involving private vehicles and occur most frequently on the weekends, suggesting potentially the missed opportunity to avoid these fatalities. We do not find similar effects for fleet vehicles. These findings remain robust to alternative specifications and alternative definitions of high pollen count. Taken together, this study finds evidence that a prevalent and transitory exogenous health-shock, namely pollen allergies, increases traffic fatalities. Given our lack of evidence of avoidance, these effects are not mechanical and are likely driven by cognitive impairments that arise as a result of seasonal allergies.
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Effect of In utero Exposure to Air Pollution on Adulthood Hospitalizations
Nicolau Martin-Bassols et al.
Journal of Urban Health, February 2024, Pages 92–108
Abstract:
Empirical analyses have demonstrated that individuals exposed to severe air pollution in utero have worse health outcomes during childhood. However, there is little evidence on the long-term health impacts of air pollution exposure. The objective of this paper is to estimate the effect of in utero exposure to the Great London Smog of 1952 (GLS) on five health outcomes identified through a scoping review to be those most likely affected: respiratory, circulatory, neoplasms, mental health, and nervous system conditions. We use the GLS, an extreme air pollution event in December 1952, as a quasi-natural experiment to estimate the effect of exposure to air pollution in utero on adulthood health. Data from the UK Biobank is analysed for a cohort of participants born from December 1952 to July 1956. Differences in health outcomes between adults exposed and not exposed to the GLS due to their birth dates, born inside and outside London, were explored. Our primary focus is hospitalization events between 1997 and 2020 (corresponding to ages 40 to 69), as recorded in linked administrative data from the National Health Service (NHS). Specifically, the five primary outcomes are binary variables indicating that the individual had at least one hospitalization where the main cause of hospitalization is related to respiratory, circulatory, neoplasms, mental health, or nervous system conditions. The analytical sample comprised 36,281 individuals. A positive effect on adulthood hospitalizations due to respiratory conditions was observed. If exposed to the GLS in utero, the probability of at least one respiratory health-related hospitalization between 1997 and 2020 increased by 2.58 percentage points (95% CI 0.08, 4.30, p = 0.03), a 23% increase relative to the sample mean. Small effects were found for all other outcomes, suggesting that these conditions were not affected by the GLS. We do not find heterogeneous effects by sex or childhood socioeconomic status. This study found that a 5-day pollution exposure event while in utero significantly increased respiratory-related hospitalizations at ages 40 to 69 but had no impact on hospitalizations due to circulatory, neoplasms, mental health, and nervous system conditions.
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Reassessing the role of urban green space in air pollution control
Zander Venter et al.
Proceedings of the National Academy of Sciences, 6 February 2024
Abstract:
The assumption that vegetation improves air quality is prevalent in scientific, popular, and political discourse. However, experimental and modeling studies show the effect of green space on air pollutant concentrations in urban settings is highly variable and context specific. We revisited the link between vegetation and air quality using satellite-derived changes of urban green space and air pollutant concentrations from 2,615 established monitoring stations over Europe and the United States. Between 2010 and 2019, stations recorded declines in ambient NO2, (particulate matter) PM10, and PM2.5 (average of −3.14% y−1), but not O3 (+0.5% y−1), pointing to the general success of recent policy interventions to restrict anthropogenic emissions. The effect size of total green space on air pollution was weak and highly variable, particularly at the street scale (15 to 60 m radius) where vegetation can restrict ventilation. However, when isolating changes in tree cover, we found a negative association with air pollution at borough to city scales (120 to 16,000 m) particularly for O3 and PM. The effect of green space was smaller than the pollutant deposition and dispersion effects of meteorological drivers including precipitation, humidity, and wind speed. When averaged across spatial scales, a one SD increase in green space resulted in a 0.8% (95% CI: −3.5 to 2%) decline in air pollution. Our findings suggest that while urban greening may improve air quality at the borough-to-city scale, the impact is moderate and may have detrimental street-level effects depending on aerodynamic factors like vegetation type and urban form.
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Air Pollution, Wildfire Smoke, and Worker Health
Marika Cabral & Marcus Dillender
NBER Working Paper, March 2024
Abstract:
Little is known about how pollution impacts worker health and workplace safety. This paper leverages high-frequency, plausibly exogenous variation in wildfire smoke to estimate the impact of pollution on workplace injuries. Our analysis draws on unique data we construct through linking information on smoke plumes and pollution to comprehensive administrative data on workers’ compensation injury claims from Texas. We first document that wildfire smoke increases ambient air pollution -- with our estimates indicating that a day of smoke coverage is associated with an average increase in PM₂.₅ of 18.6%. We find that an additional day of smoke coverage leads to a 2.8% increase in workplace injury claims. Similar percent increases in workplace injuries are found across different types of injuries and workers. However, because of large variation in baseline injury risk, the incidence of these pollution-induced injuries is concentrated among workers in high-risk occupations, and supplemental analysis illustrates potential opportunities for improving the targeting of costly mitigation. Our estimates indicate that pollution -- and wildfire smoke in particular -- substantially harms worker health, even at pollution levels well below current and proposed regulatory standards. Overall, our findings suggest workers face unique risks from pollution and provide insights for policy aiming to address these risks.