U.S. health agencies on Wednesday warned that certain blood tests for lead poisoning may give results lower than the actual level of lead.
As a result, some children under 6, along with pregnant and nursing women, may need retesting, the Food and Drug Administration and Centers for Disease Control and Prevention said.
The lead poisoning tests are made by Magellan Diagnostics. The tests should no longer be used for blood samples drawn from a vein, the agencies said. Those kinds of blood draws are usually done in labs.
Magellan blood tests from finger or heel pricks – the method usually used for children – are considered accurate. The company makes the only lead test used in doctor offices and clinics and that test uses blood from finger or heel sticks.
The agencies said women and parents should ask their doctor about retesting. Candidates include anyone whose blood was drawn for the test and who had a blood lead level of 10 micrograms or less per deciliter. While no level is considered safe, the federal safety limit is half that level.