ALBANY, N.Y. (AP) -- A group of 14 attorneys general has asked Congress to launch an investigation of the herbal supplements industry and to consider giving the U.S. Food and Drug Administration stronger oversight of the industry, New York Attorney General Eric Schneiderman announced.

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"When consumers take an herbal supplement, they should be able to do so with full knowledge of what is in that product and confidence that every precaution was taken to ensure its authenticity and purity," Schneiderman said Thursday.

Schneiderman alleged in February that DNA tests on certain store-brand supplements found none of the herbs on the labels. Industry groups and some consumer advocates have criticized Schneiderman's test method, saying DNA testing is unable to identify highly processed plant material.

GNC, one of the retailers targeted by Schneiderman, said last week that it has provided him test results from independent labs showing its products were safe and properly labeled, and has agreed to add DNA testing to its quality control procedures.

Under federal law, herbal supplements, vitamins and other dietary supplements are subject to far less rigorous oversight than pharmaceutical products.

Schneiderman noted research that has found some herbal supplements to contain high levels of heavy metals like lead, mercury, and arsenic, and a study that found a popular herbal supplement designed to reduce menopause symptoms may have caused severe liver damage in certain women.

"The FDA has long been aware of problems in the dietary and herbal supplement supply chain, from dubious ingredient sourcing to a failure to carry out proper testing on finished products," the attorneys general said in their letter sent Thursday to Kansas Sen. Jerry Moran and Pennsylvania Rep. Joe Pitts, chairmen of the subcommittees dealing with product safety and health.

Schneiderman's letter is co-signed by the attorneys general of Connecticut, District of Columbia, Hawaii, Idaho, Indiana, Iowa, Kentucky, Massachusetts, Mississippi, New Hampshire, Northern Mariana Islands, Pennsylvania, and Rhode Island.


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