Why is the risk of lead poisoning greater in the areas where the water is purer?

The risk of lead poisoning is greater in areas with purer water because the absence of certain minerals can lead to increased corrosion of lead pipes and Plumbing fixtures. In low-mineral or "soft" water, the lack of calcium and magnesium can cause water to become more aggressive in leaching lead from pipes. Consequently, when lead pipes are present, even relatively clean water can become contaminated, posing a significant health risk, particularly in older infrastructure.