Lead Poisoning Of Our Children Is Underreported In U.S.
We've all heard about the lead poisoning in Flint, Michigan -- which could seriously affect the children of that city. But most people don't realize that Flint is only a small portion of the problem of lead poisoning in the United States. It turns out that millions of children are likely affected -- and most of them go undiagnosed or treated.
We’ve long known that despite all our efforts to clean up lead, we have a serious problem with lead poisoning in American children — it’s an egregious and preventable public health issue that just won’t go away.
And it seems the problem is even worse than we thought. Researchers at the Public Health Institute reported Thursday in the journal Pediatrics that the overall number of children with elevated blood lead levels as of 1999-2010 in the US was 1.2 million, or double what the Centers for Disease Control and Prevention had reported. (The number is likely even higher now, since testing rates have only declined since 2000.) These kids who are never tested or reported to the CDC also aren’t receiving treatment.
Some states are doing much worse than others, according to the researchers. In the 11 states in dark blue on the map above, including Arizona and Florida, more than 80 percent of children with lead poisoning were not tested by their pediatricians or local health departments. For the other 28 states with data (in medium and light blue), anywhere from 40 to 60 percent of lead-poisoned children weren’t tested.
As for the 12 states in gray, researchers were unable to determine how many cases of lead poisoning were missed, because these states don’t share any data with the CDC.
So how are we failing to account for so many lead-poisoned children?
The answer (as well as the solution) is pretty straightforward. We don’t test enough children for lead, and as a result, lead poisoning cases in the US go undetected. If doctors were to test more children and if states were to mandate testing for more at-risk populations, then more children suffering from lead poisoning would get the treatment they so desperately need. It might also mean we’d get more serious about dealing with the threat of lead itself.
In 1984, 17 percent of all American preschool children had blood lead levels that exceeded 15 micrograms per deciliter, or μg/dL. But thanks to the ban of leaded paint in 1978 and the gradual phaseout of leaded gasoline in the mid-1970s, BLLs in preschool children have continued to decline overall, so that in 2014 just 0.53 percent of children tested in the US had elevated BLLs of 10 μg/dL or greater — once a threshold for the harmful effects of lead.
In 2014, the CDC found that 4.2 percent of children test, or half a million, had elevated blood lead levels of 5 (μg/dL) or greater. But Eric Roberts, the lead author of the new paper in Pediatrics, and colleagues suspected this number was incomplete.
“People talk about the great public health victory over lead, which is true, but I think it kind of blinded us,” he said.
To calculate how many lead poisoning cases in the US might be unreported, Roberts and his colleagues used the CDC’s National Health and Nutrition Examination Survey (NHANES). They also used census data on housing, race, poverty, and region of residence (all known risk factors of lead exposure) to determine rates of lead poisoning. The researchers then compared their numbers with the CDC’s reported confirmed lead poisoning cases and found that nearly 600,00 children suffering from lead poisoning (blood lead levels 10 μg/dL or greater) were not counted. And this is a conservative estimate because the CDC’s threshold for lead poisoning is now 5 μg/dL.