Early-Life Exposure to Tap Water and the Development of Cognitive Skills

To improve drinking water accessibility and safety in rural China, the Chinese government launched the rural drinking water program in the 1980s. As part of the program, tap water infrastructure has been constructed in rural areas to supply tap water to rural residents. This policy intervention provides a unique opportunity to examine the impact of early life exposure to tap water on children’s cognitive achievement in later life. Using data extracted from the China Family Panel Studies (CFPS), we find that one additional year of exposure to tap water in early life increases average cognitive test score by 0.109 standard deviations for a sample of rural children aged 10-15 in 2010. The effect is larger for children whose fathers are less-educated. Event study estimates confirm that the beneficial impacts are concentrated in early life with limited additional impact after the time window.