Foetal Exposure to Air Pollution and Students' Cognitive Performance: Evidence from Agricultural Fires in Brazil*

This paper examines the impact of foetal exposure to air pollution from agricultural fires on Brazilian students' cognitive performance later in life. We rely on comparisons across children who were upwind and downwind of the fires while in utero to address concerns around sorting and temporary income shocks. Our findings show that agricultural fires increase ${\text{PM}}_{2.5}$, resulting in significant negative effects on pupils' scores in Portuguese and Maths in the $5\text{th}$ grade through prenatal exposure. Back-of-the-envelope calculations suggest that a 1% reduction in ${\text{PM}}_{2.5}$ from agricultural burning has the potential to increase later life wages by 2.6%.