UPDATE 1-Certain lead tests could produce faulty results - U.S. regulators

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May 17 (Reuters) - Certain tests used to detect lead exposure could provide inaccurate results for some children and adults in the United States, U.S. regulators warned on Wednesday.

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 is deeply concerned ... and is warning laboratories and health care professionals that they should not use any Magellan Diagnostics' lead tests with blood drawn from a vein," Jeffrey Shuren, director of the FDA's Center for Devices and Radiological Health, said in a statement. (http://bit.ly/2pW5Bsj)

Currently, the FDA believes the issue may date back to 2014, the agency said, adding that Wednesday's warning is for all four of Magellan Diagnostics' lead testing systems: LeadCare, LeadCare II, LeadCare Plus and LeadCare Ultra.

Some laboratories offer other methods of lead testing and they are not believed to be affected at this time, the FDA noted.

Lead exposure can affect nearly every system in the body, produces no obvious symptoms, and frequently goes unrecognized, potentially leading to serious health issues.

The CDC's threshold for elevated lead is 5 micrograms per deciliter of blood. Even a slight elevation can reduce IQ and stunt childhood development.

The CDC on Wednesday recommended retesting children younger than six years if their test was conducted using blood drawn from a vein using any Magellan tests and received a result of less than 10 micrograms per deciliter (ug/dL).

The agency also urged women who are currently pregnant or nursing and were tested in this manner, to get retested.

Since last year, Reuters has identified more than 3,300 U.S. neighborhood areas with documented childhood lead poisoning rates double those found in Flint, Michigan.

Despite decades of U.S. progress in curbing lead poisoning, millions of children remain at risk. Flints disaster is just one example of a preventable public health crisis that continues in hotspots coast to coast, Reuters has found. (Reporting by Natalie Grover in Bengaluru; Editing by Maju Samuel)