Test may underestimate lead levels in children's blood

Certain tests to detect lead poisoning could produce faulty results, regulators warn

Certain tests to detect lead poisoning could produce faulty results, regulators warn

The warning is based on data that indicates that the tests, made by Magellan Diagnostics, could throw up results that are lower than the actual level of lead in the blood, according to the U.S. Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC). The FDA believes the testing issue may date to 2014, but said the scope of the problem wasn't clear until March, when Magellan provided new information as part of the FDA's review of its newest lead test.

This photo provided by Magellan Diagnostics shows the company's LeadCare Plus device used to test lead levels in blood. The warning applies to all four of Magellan Diagnostics' lead testing systems: LeadCare; LeadCare II; LeadCare Plus; and LeadCare Ultra. At this time, all LeadCare systems can be used with blood from a finger or heel stick, including the LeadCare II system - a system found in many doctors' offices and clinics. There are also other blood tests doctors and labs may use that are not Magellan, and those are not affected.

Lead exposure can lead to serious health problems, and is particularly unsafe to infants and young children. The CDC also recommends that women, who are now pregnant or nursing and were tested in this manner while pregnant or nursing, get retested.

Shuren says testing should be re-done in kids under 6 years of age who had a blood test result of 10 micrograms per deciliter or less. Shuren added that while the Magellan LeadCare system is the only FDA-cleared test specifically for lead and the primary source of lead testing for doctor's offices and clinics in the USA, it is "not the only method of testing", he said. The most common way to check children's blood is through a finger or heel stick.

Jeffrey Shuren, director of FDA's Center for Devices and Radiological Health (CDRH), said that most patients won't be affected the issue, as the majority of lead testing is done using capillary blood, and about half of all tests are processed using other unaffected methods, such as graphite furnace atomic absorption spectroscopy (GFAAS). He added that the agencies are looking into potential causes (such as the type of tubes or chemicals used during processing), and to "confirm there is no problem with the capillary blood test".

Some adults are also at risk for lead exposure, including those who work with products or materials that contain lead, the FDA said.

The CDC warns that "no safe blood lead level in children has been identified". Low-level lead exposure, even at blood lead concentrations below 5 g/dL, can increase the risk of intellectual and academic disabilities in children, and is linked to higher rates of behavioral disorders such as hyperactivity and attention deficits, and lower birth weight.

"We take this issue very seriously and will be working closely with our local health departments and health care providers to ensure they are aware of the recommendations and offering retesting as appropriate", said Dr. Eden Wells, chief medical executive of MDHHS.

Lead exposure doesn't cause noticeable symptoms, however it can damage childrens' IQ.

Children and infants are particularly vulnerable to the neurotoxic effects of lead poisoning.