São Paulo, the major sugarcane-producing state in Brazil, commands over a fifth of the world's sugarcane production.
This paper examines how the transition from manual pre-harvest burning to mechanical harvesting affected public health across São Paulo municipalities.
Using a difference-in-differences design that exploits variation in municipal sugarcane land share, we find that greater exposure to the technical change reduced hospitalizations for respiratory and circulatory diseases.
Most distinctively, we document reductions in pollution-linked congenital anomalies and in respiratory mortality among children under five. Adult mortality from respiratory and circulatory causes shows no effect.
We directly confirm the smoke mechanism: fire incidence on sugarcane fields and particulate matter concentrations fell exclusively during the harvest season, and hospitalization reductions were disproportionately concentrated in those same months.
Robustness is corroborated by wind direction: municipalities downwind of sugarcane areas benefited more. Placebo tests across other diagnostic groups confirm that effects concentrate precisely where the biological mechanism predicts.
Keywords: Sugarcane Burning; Technical Change; Health Outcomes; Air Pollution. · JEL Codes: Q52, Q55, I18.