Benjamin Q. Huynh, PhD; Elizabeth T. Chin, PhD; Mathew V. Kiang, ScD

Question  What is the extent and impact of lead-contaminated drinking water in Chicago, Illinois?

Findings  In this cross-sectional study, an estimated 68% of children younger than 6 years in Chicago are exposed to lead-contaminated drinking water, with 19% of affected children using unfiltered tap water as their primary drinking water source. Predominantly Black and Hispanic blocks were disproportionately less likely to be tested for lead yet disproportionately exposed to contaminated drinking water.

Meaning  Childhood lead exposure from drinking water is widespread in Chicago, with racial inequities in both testing rates and exposure levels.