The Food and Drug Administration and Centers for Disease Control and Prevention (CDC) have issued a warning that certain lead tests manufactured by Magellan Diagnostics might provide inaccurate results for some children and adults in the U.S. CDC recommends that parents of children younger than 6 years of age should consult a healthcare professional about whether they should be retested, as should currently pregnant women and nursing mothers who have been tested for lead exposure. Jeffrey Shuren, MD, director of FDA’s Center for Devices and Radiological Health, has said that the agency is aggressively investigating this complicated issue” to determine the cause of the inaccurate results and resolve the problem.

The warning is based on currently available data that indicate Magellan lead tests, when performed on blood drawn from a vein, might provide results that are lower than the actual level of lead in the blood. The problem seems to affect all four of Magellan’s lead testing systems—LeadCare, LeadCare II, LeadCare Plus, and LeadCare Ultra—and FDA believes it could date back to 2014. However, the issue does not seem to extend to LeadCare tests performed with a finger or heel stick sample. At this time, the agency states that all LeadCare systems can still be used with blood obtained in this manner, including the LeadCare II system, which is found in many doctors’ offices and clinics.

Concurrent with the release of FDA’s warning, Magellan Diagnostics separately informed institutions with LeadCare testing systems about this problem. In this notice, Magellan stated that the company is working with FDA to address the concerns with venous samples as quickly as possible.