Women exposure to household air pollution after an improved cookstove program in rural San Luis Potosi, Mexico.

•Kitchen and patio PM2.5 levels using solid fuels in a Mexican rural context.•The impact evaluation lost validity because of non-comparable groups.•“Real scenario” analysis: an alternative evaluation of factors related to air pollution exposure.•Wealthier households are more likely to present patterns of fuel-devices stacking.•Improved cookstoves in good conditions or LPG can reduce daily PM2.5 exposure up to 10 µg/m3.