(NEW YORK) — The Biden administration recently announced a proposal that would require all lead water service pipes to replaced in the United States within the next decade.

The proposal, led by the Environmental Protection Agency (EPA), is an attempt to protect Americans from lead exposure, which can cause severe health issues in children and adults, including developmental delays, kidney damage and pregnancy complications.

There are more than 9.2 million lead pipes throughout the country, but there are certain states that would particularly benefit from the proposal.

Four states — Florida, Illinois, Ohio and Pennsylvania — contain nearly 40% of all lead service lines in the U.S. at more than 3.63 million total, according to an April 2023 report from the EPA.

Dr. Aaron Packman, professor of civil and environmental engineering at Northwestern University and director of the Northwestern Center for Water Research, said there are two issues in Illinois: one being the government-owned city water infrastructure and the other being the lines people own individually on their properties.

“The issue with the city infrastructure, a lot of it is old … and it’s been under maintained over the last few decades because of decreasing federal funding available for water infrastructure,” he told ABC News. “The bigger issue we have now is that lead was widely used to connect the water mains in the street to people’s houses.”

He continued, “And so there are enormous numbers of these lead service lines, as they’re called, that are in people’s front yards or coming into their apartment building or school, and it’s harder for city governments typically to conduct work on private property.”

Residents of Chicago, in particular, would be greatly impacted by the initiative because nearly 400,00 lead water pipes are located in the city — the most of any city in the U.S. In the early 20th century, an agreement negotiated between plumbers’ unions and the lead industry resulted in a requirement of using lead in pipes, “so they’re just everywhere,” Packman said.

Considering the monumental challenge of replacing so many lines, the EPA has made an exception and is allowing Chicago to take 40 to 50 years to replace its pipes, according to local media reports.

“This is long-term fallout from bad industrial governmental decisions 50-plus years ago,” Packman said. “It’s larger cities, older cities with older infrastructure and are more densely populated or more built up, all of those factors make this take longer, be more challenging.”

Pennsylvania may also benefit from the proposal. In Philadelphia, similar agreements around the same time period also resulted in lead being required in the city’s pipes.

Additionally, a February 2023 report from the nonprofit Environment America revealed that despite Pennsylvania law requiring schools to test some taps for lead every year, a loophole allows districts to avoid testing taps by holding a public meeting to discuss the issue.

As of 2018, Pennsylvania was one of the states with the highest blood levels reported among kids, Centers for Disease Control and Prevention (CDC) data shows.

According to the CDC, children under the age of 6 are at greatest risk for health problems due to lead exposure, which can affect growth and development.

“For children, we see developmental delays and behavior problems related to lead exposure, because it is a very potent neurotoxin,” Dr. Ruth McDemott-Levy, professor & co-director of the Mid-Atlantic Center for Children’s Health and the Environment, at Villanova University, told ABC News. “And so, if we don’t catch it quickly enough … we’re talking about lifelong problems for the child and, that can affect the ability to perform well in school, to get a decent paying job.”

But it’s not just children. Adults can also suffer health consequences from lead exposure including high blood pressure, gastric discomfort and kidney issues, McDermott-Levy said.

Additionally, if a pregnant woman is exposed to lead over a long period or has prior high blood levels, the toxin can cross the placenta to the fetus and increase the risk of miscarriage, neurocognitive damage, premature birth or low-birth weight, according to the CDC.

She added that the proposed rule would really benefit low-income families of color, who are most impacted by lead exposure, including in water. For a city like Philadelphia, which is considered the nation’s poorest large city by poverty rate, according to 2022 Census Bureau data, that would certainly be the case.

“For example, we filter our water; it’s just a given that’s what we do and we can do that,” McDermott-Levy said. “But not everyone can afford that or can keep up with changing the filter and all of those sorts of things. So, I think it’s going to have the greatest impact on low-income people of color.”

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