On the Road to Recovery: Gasoline Content Regulations and Child Health, Journal of Health Economics 54 (2017): 98-123.
Gasoline content regulations are designed to curb pollution and improve health, but the impact on health has not been quantified. By exploiting both the timing of regulation and spatial variation in children’s exposure to highways, I estimate the effect of gasoline regulation on pollution and child health. The introduction of cleaner-burning gasoline in California in 1996 reduced asthma admissions by 8% in high exposure areas. Reductions are greatest for areas downwind from highways and heavy traffic areas. Stringent gasoline content regulations can improve child health, and may diminish existing health disparities.
Going Beneath the Surface: Petroleum Pollution, Regulation, and Health (R&R American Economic Journal: Applied Economics)
Governments can address the growing concern over human exposure to environmental pollution through directing cleanup efforts ex-post, regulating industry to reduce future pollution, or warning the public to encourage avoidance behaviors. While we have some evidence of the benefits of large government cleanups, we have less evidence of the benefits of mandated adoption of preventative technology. This paper quantifies the health impacts of a relatively small but widespread pollution source and explores whether the adoption of preventative technologies can improve health. I estimate the effect of exposure to leaking underground storage tanks on infant health using data on maternal addresses to identify precise proximity to sites, and leak timing data to determine exposure during gestation. By exploiting panel data on mothers, I estimate the relative difference in sibling outcomes between exposed and unexposed siblings born to mothers within two narrow distance bands from a leak site. Exposure increases both the probability of low birth weight and preterm birth by about 7-8 percent. Compliance with regulations requiring preventative technologies ultimately succeeded in mitigating the entire effect of leak exposure on low birth weight. Finally, I exploit this unique setting in which residents are unlikely to know about underground leaks to study the impact of information on avoidance behaviors.
Testing the Water: Drinking Water Quality, Public Notification, and Child Outcomes (under review)
About 1 in 12 Americans are exposed to health-based drinking water violations each year, yet we know relatively little about the health and human capital benefits of drinking water regulation. This is the first paper to study the impact of drinking water quality violations on children and adolescents in the US. I take a comprehensive approach to quantify the costs of poor drinking water quality by considering avoidance behavior (bottled water purchases), human health (stomach remedy purchases and ER visits for gastrointestinal illness), and human capital (school absences and test scores). I find that individuals successfully avoid negative health impacts of coliform bacteria only when informed immediately. Bottled water sales increase during coliform bacteria violations that require 24-hour public notice, but not during violations that require 30-day public notice, despite impacts on health, school absences and test scores. Timely public notification is a cost-effective way to induce avoidance behavior and protect health when water quality is poor.
A Little Pain for Birth Weight Gain: Influenza Vaccine Match Rate and Neonatal Health (with Desislava Byanova and Joseph Acquah)
Research studying short and long-run impacts of influenza are predominantly focused on flu pandemics, when the negative implications are most stark. However, many of these pandemics occurred in the early 20th century before the substantial decline in influenza-related mortality driven by new medical technologies and advancement in hygiene practices. Consequently, the impact of the modern day non-pandemic influenza season may be substantially different from the impact of pandemics occurring in the early part of the 20th century. This paper exploits exogenous variation in vaccine match rate quality and addresses the endogeneity of seasonal influenza severity and vaccination rates by using absolute humidity and an exogenous vaccine supply shock as instruments, in order to quantify the impact of seasonal influenza severity and vaccine effectiveness on birth outcomes in a developed, modern day context. Findings indicate that a one-standard-deviation increase in the vaccine match rate or the vaccination rate leads to a 4 percent or 2 percent decrease in the probability of low birth weight and a 9 percent or 4 percent decrease in the probability of preterm birth, respectively.
Aerobic Capacity and Pollution at Schools
As required by the Clean Air Act, the EPA sets National Ambient Air Quality Standards (NAAQS) to protect public health, including the health of sensitive populations such as children. Exiting research has documented the effect of pollution on severe health outcomes, such as hospitalizations for asthma and infant death. However, lacking information on less extreme measures of respiratory health, standards for criteria pollutants have been set without full knowledge of the health consequences of air pollution for children. Less extreme effects on respiratory health, even among non-asthmatic children, are possible at levels even below the EPA’s thresholds, but these effects are difficult to measure. I use a more sensitive measure, aerobic capacity (VO2max), to study the impact of air pollution on respiratory health at levels below current NAAQS thresholds. I combine school-grade level data from the California Physical Fitness Test from 2009-2017 with local air pollution and weather data to estimate the impact of fluctuations in daily pollution levels on testing dates on student aerobic capacity. Ozone affects child aerobic capacity at levels even below the EPA thresholds. I explore heterogeneous effects by race, ethnicity, income, and gender, and find effects are especially large for disadvantaged groups.
The Impact of Maritime Emissions Standards on Air Quality and Infant Health (with Jamie Hansen-Lewis)
The bulk of ship traffic occurs near coastlines and pollution from ship exhaust is a major component of poor air quality on populated US coasts. In this paper, we measure the effect of maritime fuel emissions standards on air quality and infant health.
We employ the predictions of an atmospheric aerosol transport model to form a rigorous scientific prior on the change in air pollution from maritime emissions standards at a given location accounting for the atmospheric dispersion, disposition, and chemical interactions of pollution once emitted. We combine these predictions with administrative data of air quality and births to estimate the policy’s outcomes and to directly compare the ex-post changes in air pollution from the policy with the ex-ante scientific predictions. We find that the introduction of maritime emissions control areas around the US West Coast led to a substantial 65% average fall in sulfur dioxide concentrations as well as a 5.0% fall in fine particulate matter and 6.8% fall in coarse particulate matter. Consistent with the air quality improvements, we find a 2.7% average reduction in the incidence of low infant birth weight due to the policy. While we cannot reject that the ex-ante and ex-post estimates are the same, we estimate that roughly 75% of the intended fine particulate matter improvements were actualized.
Selected Work In Progress
The Effect of Free School Meals on Household Food Purchases: Evidence from the Nielsen Consumer Panel (with Katherine Yewell)
The Effect of Immigration Enforcement on Immigrant Health Care Utilization and Spillovers to Native Health (with Chloe East)