Air Pollution and Student Learning in Pakistan

Overview & Synopsis

Ambient air pollution is a major health risk, but its implications for human capital formation are not well understood, particularly in low- and middle-income countries where exposure is high. This paper estimates the causal effect of sustained exposure to fine particulate matter on primary-school learning in rural Punjab, Pakistan. The paper combines longitudinal student achievement data from the Learning and Educational Achievements in Punjab Schools project with high-resolution satellite-based fine particulate matter estimates. To address endogeneity of pollution to local economic activity, the analysis exploits plausibly exogenous variation generated by open burning of agricultural residue interacted with wind direction, constructing school-year measures of upwind fire exposure as instruments for local fine particulate matter. The instrumental variable estimates show that higher school-year fine particulate matter significantly slows learning, with larger effects in mathematics than in language subjects. The results are consistent with impacts operating during instructional months: pollution exposure during the school year predicts lower achievement, while exposure during vacation months has little explanatory power. The findings show statistically imprecise heterogeneity by age and gender, opposite to patterns found in comparable settings. The analysis is organized around a simple framework in which learning depends on attendance, cognition, effort, and instructional quality, each a function of exposure to poor air quality. Pollution increases student absences, but this attendance channel explains only a small portion of the total effect, implying that most of the learning loss is non-attendance-related and likely operates through the framework’s other channels — direct effects on cognition, reduced effort, and degraded instructional quality.