The water crisis in Flint, Michigan, may have reduced fertility rates and increased miscarriages and fetal deaths, according to new research exploring one impact of lead poisoning on the population.
The number of fetal deaths ― pregnancies that lasted longer than 20 weeks but didn’t result in a live birth ― increased 58 percent from 2014 to 2016, when the city had higher amounts of lead in its water, researchers found. The number of live births declined 12 percent.
Overall, “between 198 and 276 more children would have been born had Flint not enacted the switch in water,” according to the working paper by Daniel Grossman of West Virginia University and David Slusky of the University of Kansas. Using other Michigan cities for comparison, the pair looked at fertility and fetal death rates in Flint before and after the city’s water became contaminated with lead.
“It’s a tragic but unintentionally well-set-up natural experiment,” Slusky said in an interview.
Flint is one of many American cities that installed lead water pipes in the 20th century, despite dangers including child brain damage and a range of health problems. The deadly neurotoxin has since been banned from most household applications, but millions of lead water service lines are still in use around the country. Rather than replace them, federal law requires cities to add chemicals to their water so it forms a protective coating on the inside of the pipes, thereby preventing corrosion that allows lead particles to leach into people’s drinking water. Flint failed to treat its water correctly after changing its water source to the Flint River in 2014.
Most of the effects of leaded water can only be observed through population-level analysis. As water utilities love to point out, even if somebody has documented higher lead levels in his or her blood, that person can’t definitively say what caused the increase. It could have been the water, but it also could have been dust from old paint or lead-contaminated dirt.
Slusky noted that the increase in fetal deaths was similar to an increase observed by researchers in Washington, D.C., after a chemical treatment change caused the water to leach lots of lead from the city’s old pipes. A 2014 study by Virginia Tech’s Marc Edwards revealed that fetal death rates rose as much as 63 percent in the District of Columbia after treatment changes spiked the city’s water with lead in 2001.
Edwards said in an email that other researchers will probably replicate the Flint results, which he said seemed larger than he expected. Edwards previously estimated that the D.C. lead crisis was 20 to 30 times worse than the one in Flint.
“The magnitude of the effect appears to be larger than I would predict based on the exposures that we think occurred ― but what we think is also very often wrong,” Edwards said in an email.
Officials in Washington never admitted their mistakes poisoned thousands of residents in the city, and officials in Flint and the Michigan state government denied Flint’s water was unsafe ― at least until a local pediatrician, Dr. Mona Hanna-Attisha, conducted research revealing late in 2015 that lead levels in Flint kids’ blood had doubled. The city of Flint, which at the time was under the control of an emergency manager appointed by Michigan Gov. Rick Snyder (R), almost immediately resumed buying water from Detroit instead of pumping from the Flint River.
Since then, extensive state, federal and independent testing of Flint’s water has shown lead levels below the Environmental Protection Agency’s “action level,” the agency’s threshold for requiring a water utility to remediate. The EPA’s regulation is notoriously porous; not even Flint got cited for a violation at the height of its crisis.
The Lead and Copper Rule, as the regulation is known, doesn’t require utilities to get rid of lead pipes if the poison is present in a town’s water. The EPA is currently revising the rule, though it’s hard to tell from a white paper the agency released last year how aggressive the revised regulation will be on lead pipes.