The U.S. Food and Drug Administration (FDA) has directed cigarette companies to provide detailed information on their products by June, when the agency for the first time will begin studying the composition of cigarettes in detail, the  Associated Press reported Jan. 18.

Tobacco companies also must give the FDA any research they have conducted on the effects of cigarette ingredients.

The FDA will classify the ingredients, determine their relative harm, and possibly ban some ingredients or combinations thereof. Information protected under trade-secret laws won't be publicly disclosed, but the FDA is mandated to publish a list of harmful and potentially dangerous ingredients by the middle of next year.

"Tobacco products today are really the only human-consumed product that we don't know what's in them," said Lawrence R. Deyton, the director of the FDA's Center for Tobacco Products.