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I examine the effect of school indoor air quality (IAQ) on academic outcomes. I utilize a quasi-natural experiment, in which IAQ-renovations were completed at virtually every school in a single Texas school district at different points in time, combined with a panel of student-level data to control for many confounding factors and thereby uncover the causal effect of IAQ-renovations on academic outcomes. Results indicate that performance on standardized tests significantly improves while attendance is unresponsive to improvements in IAQ. Rough calculations suggest that IAQ-renovations may be a more cost-effective way to improve standardized test scores than class size reductions.

Published Nov 2, 2014

Stafford, T. M. (2015). Indoor air quality and academic performance. Journal of Environmental Economics and Management, 70, 34–50. https://doi.org/10.1016/j.jeem.2014.11.002

Cognitive performance is critical to productivity in many occupations and potentially linked to pollution exposure. We evaluate this potentially important relationship by estimating the effect of pollution exposure on standardized test scores among Israeli high school high-stakes tests (2000-2002). Since students take multiple exams on multiple days in the same location after each grade, we can adopt a fixed effects strategy estimating models with city, school, and student fixed effects. We focus on fine particulate matter (PM2.5) and carbon monoxide (CO), which are considered to be two of the most dangerous forms of air pollution. We find that while PM2.5 and CO levels are only weakly correlated with each other, both exhibit a robust negative relationship with test scores. We also find that PM2.5, which is thought to be particularly damaging for asthmatics, has a larger negative impact on groups with higher rates of asthma. For CO, which affects neurological functioning, the effect is more homogenous across demographic groups. Furthermore, we find that exposure to either pollutant is associated with a significant decline in the probability of not receiving a Bagrut certificate, which is required for college entrance in Israel. The results suggest that the gain from improving air quality may be underestimated by a narrow focus on health impacts. Insofar as air pollution may lead to reduced cognitive performance, the consequences of pollution may be relevant for a variety of everyday activities that require mental acuity. Moreover, by temporarily lowering the productivity of human capital, high pollution levels lead to allocative inefficiency as students with lower human capital are assigned a higher rank than their more qualified peers. This may lead to inefficient allocation of workers across occupations, and possibly a less productive workforce

Published Oct 1, 2014

Lavy, V., & Roth, S. (2014). The Impact of Short Term Exposure to Ambient Air Pollution on Cognitive Performance and Human Capital Formation. National Bureau of Economic Research, 1–40. https://doi.org/10.3386/w20648

Investigate whether air pollution affect academic performance of school children in California using fixed effect least squares regression and fixed effect quantile regression. This issue has not be studied previously by economists; the two studies in the epidemiological literature considering it would not be considered as measuring causal effects by economists. Quantile regression allows us to investigate how pollution affects different parts of the achievement distribution, and has not been used previously in this literature.

Published Apr 1, 2014

Avol, J. C. H. J. S. Z. ; E. (2014). Pollution, Test Scores and the Distribution Of Academic Achievement: Evidence From California Schools, 2002-2008. https://www.smu.edu.sg/sites/default/files/economics/shea2014/presentation/pollution_talk_april_2014_ham2.pdf

Background: Inhaling fine particles (particulate matter with diameter ≤ 2.5 μm; PM2.5) can induce oxidative stress and inflammation, and may contribute to onset of preterm labor and other adverse perinatal outcomes.

Objectives: We examined whether outdoor PM2.5 was associated with adverse birth outcomes among 22 countries in the World Health Organization Global Survey on Maternal and Perinatal Health from 2004 through 2008.

Methods: Long-term average (2001–2006) estimates of outdoor PM2.5 were assigned to 50-km–radius circular buffers around each health clinic where births occurred. We used generalized estimating equations to determine associations between clinic-level PM2.5 levels and preterm birth and low birth weight at the individual level, adjusting for seasonality and potential confounders at individual, clinic, and country levels. Country-specific associations were also investigated.

Results: Across all countries, adjusting for seasonality, PM2.5 was not associated with preterm birth, but was associated with low birth weight [odds ratio (OR) = 1.22; 95% CI: 1.07, 1.39 for fourth quartile of PM2.5 (> 20.2 μg/m3) compared with the first quartile (< 6.3 μg/m3)]. In China, the country with the largest PM2.5 range, preterm birth and low birth weight both were associated with the highest quartile of PM2.5 only, which suggests a possible threshold effect (OR = 2.54; CI: 1.42, 4.55 and OR = 1.99; CI: 1.06, 3.72 for preterm birth and low birth weight, respectively, for PM2.5 ≥ 36.5 μg/m3 compared with PM2.5 < 12.5 μg/m3). Conclusions: Outdoor PM2.5 concentrations were associated with low birth weight but not preterm birth. In rapidly developing countries, such as China, the highest levels of air pollution may be of concern for both outcomes.

Published Apr 1, 2014

Fleischer NL, Merialdi M, van Donkelaar A, Vadillo-Ortega F, Martin RV, Betran AP, Souza JP, O´Neill MS. 2014. Outdoor air pollution, preterm birth, and low birth weight: analysis of the World Health Organization Global Survey on Maternal and Perinatal Health. Environ Health Perspect 122:425–430;  http://dx.doi.org/10.1289/ehp.1306837

Polycyclic aromatic hydrocarbons (PAH) are major toxic air pollutants released during incomplete combustion of coal. PAH emissions are especially problematic in China because of their reliance on coal-powered energy. The prenatal period is a window of susceptibility to neurotoxicants. To determine the health benefits of reducing air pollution related to coal-burning, we compared molecular biomarkers of exposure and preclinical effects in umbilical cord blood to neurodevelopmental outcomes from two successive birth cohorts enrolled before and after a highly polluting, coal-fired power plant in Tongliang County, China had ceased operation. Women and their newborns in the two successive cohorts were enrolled at the time of delivery. We measured PAH-DNA adducts, a biomarker of PAH-exposure and DNA damage, and brain-derived neurotrophic factor (BDNF), a protein involved in neuronal growth, in umbilical cord blood. At age two, children were tested using the Gesell Developmental Schedules (GDS). The two cohorts were compared with respect to levels of both biomarkers in cord blood as well as developmental quotient (DQ) scores across 5 domains. Lower levels of PAH-DNA adducts, higher concentrations of the mature BDNF protein (mBDNF) and higher DQ scores were seen in the 2005 cohort enrolled after closure of the power plant. In the two cohorts combined, PAH-DNA adducts were inversely associated with mBDNF as well as scores for motor (p = 0.05), adaptive (p = 0.022), and average (p = 0.014) DQ. BDNF levels were positively associated with motor (p = 0.018), social (p = 0.001), and average (p = 0.017) DQ scores. The findings indicate that the closure of a coal-burning plant resulted in the reduction of PAH-DNA adducts in newborns and increased mBDNF levels that in turn, were positively associated with neurocognitive development. They provide further evidence of the direct benefits to children's health as a result of the coal plant shut down, supporting clean energy and environmental policies in China and elsewhere.

Published Mar 19, 2014

Tang, D., Lee, J., Muirhead, L., Li, T. Y., Qu, L., Yu, J., & Perera, F. (2014). Molecular and Neurodevelopmental Benefits to Children of Closure of a Coal Burning Power Plant in China. PLOS ONE, 9(3), e91966. https://doi.org/10.1371/JOURNAL.PONE.0091966

Introduction: The Port of Charleston, one of the busiest US ports, currently operates five terminals. The fifth terminal is being planned for expansion to accommodate container ships from the proposed Panama Canal expansion. Such expansion is expected to increase traffic within local vulnerable North Charleston neck communities by at least 7,000 diesel truck trips per day, more than a 70% increase from the present average rate of 10,000 trucks per day. Our objective was to measure the current particulate matter (PM) concentrations in North Charleston communities as a baseline to contrast against future air pollution after the proposed port expansion. Methods: Saturation study was performed to determine spatial variability of PM in local Charleston neck communities. In addition, the temporal trends in particulate air pollution within the region were determined across several decades. With the BGI sampler, PM samples were collected for 24 hours comparable to the federal reference method protocol. Gravimetric analysis of the PM filter samples was conducted following EPA protocol. Results: The range of the PM10 annual average across the region from 1982 to 2006 was 17.0-55.0 μg/m3. On only two occasions were the records of PM10 averaged above the 50.0 μg/m3 national standard. In the case of PM2.5, the annual average for 1999-2006 ranged from 11.0 to 13.5 μg/m3 and no annual average exceeded the 15.0 μg/m3 PM2.5 annual standard. Conclusions: Although ambient PM levels have fallen in the Charleston region since the 1960s due to aggressive monitoring by the stakeholders against air pollution, local air pollution sources within the North Charleston neck communities have consistently contributed to the PM levels in the region for several decades. This baseline assessment of ambient PM will allow for comparisons with future assessments to ascertain the impact of the increased truck and port traffic on PM concentrations.

Published Mar 12, 2014

Svendsen, E. R., Reynolds, S., Ogunsakin, O. A., Williams, E. M., Fraser-Rahim, H., Zhang, H., & Wilson, S. M. (2014). Assessment of Particulate Matter Levels in Vulnerable Communities in North Charleston, South Carolina prior to Port Expansion. Environmental Health Insights, 8, EHI.S12814. https://doi.org/10.4137/EHI.S12814

Long-term exposure to traffic pollution has been associated with adverse health outcomes in children and adolescents. A significant number of schools may be located near major roadways, potentially exposing millions of children to high levels of traffic pollution, but this hypothesis has not been evaluated nationally. We obtained data on the location and characteristics of 114,644 US public and private schools, grades prekindergarten through 12, and calculated their distance to the nearest major roadway. In 2005-2006, 3.2 million students (6.2%) attended 8,424 schools (7.3%) located within 100 m of a major roadway, and an additional 3.2 million (6.3%) students attended 8,555 (7.5%) schools located 100-250 m from a major roadway. Schools serving predominantly Black students were 18% (95% CI, 13-23%) more likely to be located within 250 m of a major roadway. Public schools eligible for Title I programs and those with a majority of students eligible for free/reduced price meals were also more likely to be near major roadways. In conclusion, 6.4 million US children attended schools within 250 m of a major roadway and were likely exposed to high levels of traffic pollution. Minority and underprivileged children were disproportionately affected, although some results varied regionally.

Published Feb 5, 2014

Kingsley, S. L., Eliot, M. N., Carlson, L., Finn, J., Macintosh, D. L., Suh, H. H., & Wellenius, G. A. (2014). Proximity of US schools to major roadways: A nationwide assessment. Journal of Exposure Science and Environmental Epidemiology, 24(3), 253–259. https://doi.org/10.1038/jes.2014.5

In addition to the morbidity and mortality concerns of outdoor air pollution, studies have shown that air pollution also generates problems for children's cognitive performance and human capital formation. High concentrations of pollutants can affect children's learning process by exacerbating respiratory illnesses, fatigue, absenteeism and attention problems. The purpose of this work is to analyze the possible contemporary effects of PM10 and other different air pollutants on standardized test scores in Chile. It examines results for 3,880 schools in the Metropolitan, Valparaiso and O’Higgins regions for children in fourth, eight and tenth grades between 1997 and 2012. Data for particulate matter (PM10 and PM2. 5), carbon monoxide (CO), nitrogen oxide (NOx) and ozone (O3) were interpolated at school level using a kriging methodology. The results suggest that higher annual P M10 and O3 levels are clearly associated with a reduction in test scores. Nonetheless, as of 2012 many municipalities in these Chilean regions are still exceeding the annual P M10 international standard quality norm (50 micrograms per cubic meter) by 15 micrograms per cubic meter on average. Efforts to reduce pollution below this norm in the most polluted municipalities would account for improvements in reading and math test scores of 3. 5 percent and 3. 1 percent of a standard deviation, respectively.

Published Dec 1, 2013

Miller;, S., & Vela, M. (2013). The Effects of Air Pollution on Educational Outcomes: Evidence from Chile. Inter-American Development Bank.

Background
Although studies suggest that exposure to pollutants is associated with race/ethnicity and socio-economic status (SES), many studies are limited to the geographic regions where monitoring stations are located.

Results
SES and race/ethnicity were related to predicted concentrations of both PM2.5 and O3 for census tracts in North Carolina. Lower SES and higher proportion minority population were associated with higher levels of PM2.5. An interquartile range (IQR) increase of median household income reduced the predicted average PM2.5 level by 0.10 µg/m3. The opposite relationship was true for O3. An IQR increase of median household income increased the predicted average O3 measure by 0.11 ppb.

Conclusions
The analyses demonstrate that SES and race/ethnicity are related to predicted estimates of PM2.5 and O3 for census tracts in North Carolina. These findings offer a baseline for future exposure modeling work involving SES and air pollution for the entire state and not just among the populations residing near monitoring networks.

Published Oct 1, 2013

Gray, S. C., Edwards, S. E., & Miranda, M. L. (2013). Race, socioeconomic status, and air pollution exposure in North Carolina. Environmental Research, 126, 152–158. https://doi.org/10.1016/j.envres.2013.06.005

Climate change is a health threat no less consequential than cigarette smoking. Increased concentrations of greenhouse gases, and especially CO 2, in the earth's atmosphere have already warmed the planet substantially, causing more severe and prolonged heat waves, temperature variability, air pollution, forest fires, droughts, and floods, all of which put respiratory health at risk. These changes in climate and air quality substantially increase respiratory morbidity and mortality for patients with common chronic lung diseases such as asthma and COPD and other serious lung diseases. Physicians have a vital role in addressing climate change, just as they did with tobacco, by communicating how climate change is a serious, but remediable, hazard to their patients. © 2013 American College of Chest Physicians.

Published May 1, 2013

Bernstein, A. S., & Rice, M. B. (2013). Lungs in a warming world: Climate change and respiratory health. Chest, 143(5), 1455–1459. https://doi.org/10.1378/chest.12-2384