Lead testing systems made by Magellan Diagnostics may provide inaccurate results for some children and adults, the Food and Drug Administration and Centers for Disease Control and Prevention warned Wednesday. “The FDA is deeply concerned by this situation and is warning laboratories and health care professionals that they should not use any Magellan Diagnostics’ lead tests with blood drawn from a vein,” said Jeffrey Shuren, M.D., director of the FDA’s Center for Devices and Radiological Health. “The agency is aggressively investigating this complicated issue to determine the cause of the inaccurate results and working with the CDC and other public health partners to address the problem as quickly as possible.” CDC recommends that health care providers retest children under age 6, currently pregnant women and nursing mothers who had a venous blood lead test result of less than 10 micrograms per deciliter using a Magellan Diagnostics’ LeadCare analyzer at an onsite health care facility or offsite laboratory.