Study finds 129,000 Chicago children under 6 have been exposed to lead-contaminated water

CHICAGO (CBS) — A study released Monday estimated that about 129,000 Chicago children under 6 have been exposed to lead in drinking water.

The study also found that predominantly Black and Latino populations were disproportionately less likely to be tested for lead, but also disproportionately exposed to contaminated drinking water.

The study, published in the journal JAMA Pediatrics, found that 68 percent of children 6 and under in Chicago have been exposed to lead-contaminated drinking water – and 19 percent of those children use unfiltered tap water as tehri primary source of drinking water.

Investigators used a retrospective assessment of lead exposure based on 38,385 household lead tests collected from January 2016 until September 2023. The information was publicly available from Department of Water Management records.

Machine learning and microsimulation were then used to estimate childhood lead exposure citywide, the study said.

The study defined water to be contaminated if the majority of the tests within a census block had 1 part per billion or more of lead concentration on the second draw. This value was chosen on the grounds that no amount of lead in drinking water at all is considered safe, and because 1 ppb is the limit for detection in lead water tests.

The study warned that increased blood lead levels in children can cause cognitive development deficits and other health hazards.

“The impact of low-level, long-term exposure to lead-contaminated drinking water may not be easily identifiable at the individual level,” the study said. “Instead, it could cause population-level increases in adverse health outcomes, such as lower population-level mean IQ or increased preterm births, underscoring the need for reduced exposure to lead-contaminated drinking water.”

The study also concluded that Black and Latino households disproportionately drink bottled water, while white households disproportionately drink tap water. But the study emphasized that bottled water is not necessarily less contaminated with lead than tap water – as the U.S. Food and Drug Administration sets the lower limit for lead in bottled water at 5 ppb. The study also found that using filtered tap water doesn’t necessarily prevent lead exposure either.

“The racial and ethnic disparities present are indicative of the myriad ways environmental racism can manifest. Lower screening rates, lower consumption of tap water, and higher levels of lead exposure among predominantly Black and Hispanic blocks may indicate mistrust toward water sources or lack of community engagement from relevant authorities,” the study said. “Neighborhoods with high-risk estimates as well as low screening rates were largely clustered in the South and West sides of the city, corresponding to the city’s geographic history of segregation and disinvestment.”

The City of Chicago says lead testing in the city shows the water meets the standards of the U.S. Environmental Protection Agency.

Chicago has 380,000 lead service lines. City officials have estimated it will cost up to $9 billion to replace all of them.

This past November, the Biden administration announced a $336 million low-interest loan for Chicago through the Water Infrastructure Finance and Innovation Act to replace up to 30,000 lead pipes.

The study was authored by Benjamin Huynh and Elizabeth Chin of Johns Hopkins Bloomberg School of Public Health, and Mathew Kiang of the Stanford University School of Medicine.