Similar claims in the past have not been confirmed, the agency said.
The Campaign for Safe Cosmetics said that a third of the 33 red lipsticks examined by an independent lab contained a level of lead exceeding 0.1 parts per million - which is the FDA's limit for lead in candy. The FDA does not set a limit for lead in lipstick.
In the group's report, "A Poison Kiss: The Problem of Lead in Lipstick," some of the brands testing positive for lead were L'Oreal's Colour Riche "True Red" (0.65 ppm) and "Classic Wine" (0.58 ppm), Cover Girl Incredifull Lipcolor "Maximum Red" (0.56 ppm), Christian Dior Addict "Positive Red" (0.21 ppm), and Maybelline's Moisture Extreme "Cocoa Plum" (0.19 ppm) and "Midnight Red" (0/18 ppm).
The organization commissioning the lipstick study said its goal is to pressure companies to remove toxic chemicals from their products and replace them with safer alternatives. The lead tests were conducted by an independent laboratory last month on red lipsticks bought in Boston, San Francisco, Minneapolis and Hartford, Conn., the organization said.
The FDA said concerns about lead in lipstick have been raised occasionally in the print media and on the Internet.
"These concerns have not generally been supported by FDA's own analysis of products on the market. In the present case, we are looking into the specific details of the issues raised," said Stephanie Kwisnek, a spokeswoman at the FDA. "We will need to confirm the factual basis of these reports independently in order to determine what action, if any, may be needed to protect public health."
The trade association representing the cosmetic industry acknowledged "negligible" levels of lead in some lipsticks, but said it is not intentionally added.
Lead may be found in certain colorants, or is a by-product of raw materials such as zinc oxide, titanium dioxide, ozokerite (mineral wax or paraffin) and petroleum-based ingredients (petrolatum, mineral oil) that are introduced into the production process.
"Consumers are exposed daily to lead when they eat, drink water and breathe the air," said John Bailey, an executive vice president at the Cosmetic, Toiletry and Fragrance Association. "The average amount of lead a woman would be exposed to when using cosmetics is 1,000 times less than the amount she would get from eating, breathing, and drinking water that meets Environmental Protection Agency drinking water standards."