The problem with lead poisoning in children is that it can’t be treated, only prevented, and it can begin affecting someone during their mother’s pregnancy if she’s exposed to lead. A new study performed by lab testing service Quest Diagnostics with results announced this week shows an alarming number of kids in some parts of the country have unsafe levels of lead in their blood, and there isn’t anything that we can do about it once they’ve been exposed.

The study was simple enough: researchers went back in blood test records and analyzed tests belonging to millions of kids under 6. The results were tragically predictable. Generally, lead levels went down over the period that the samples were taken, which ran from 2009 to 2015.

While only about 3% of kids nationwide had dangerously high lead levels, up to 10% of children in areas of the Rust Belt where there’s older housing stock do.

While any lead in a child’s blood is bad, the Centers for Disease Control and Prevention actually have a number that’s they’re threshold for concern. That’s five micrograms per deciliter, and the percentage of kids tested with lead levels that high or higher jumps along with the amount of housing stock built before 1950 in an area… and the amount of poverty.

In some Zip codes, 1 in 7 children suffer from dangerously high blood lead levels [Washington Post]

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