NPR:
“Lead problems with the water in Flint, Mich., have prompted people across the country to ask whether they or their families have been exposed to the toxic metal in their drinking water, too. When it comes to assessing the risk, it’s important to look in the right places.
Even when municipal water systems’ lead levels are considered perfectly fine by federal standards, the metal can leach into tap water from lead plumbing....
When there is a problem with lead in drinking water, service lines are the most likely culprit. Service lines are like tiny straws that carry water from a utility’s water main, usually running below the street, to each building. In older cities, many of them in the Midwest and Northeast, these service lines can be made of pure lead.
Dr. Bruce Lanphear has spent decades researching low-level lead exposure, and his work is often cited by the Centers for Disease Control and Prevention. He says that while blood lead levels have been reduced drastically in recent decades, even levels as low as 5 micrograms per deciliter can lower IQs and increase the risk of attention and behavioral problems in children. For adults, lead exposure can cause kidney problems and high blood pressure.
Because it would be unethical to expose people to a known toxin, clear data are lacking on exactly how much lead a person must be exposed to before it shows up in the blood or triggers health and behavioral problems. Public health officials say that removing all lead from a person’s environment is the best course of action.”
