NEW YORK (CNNMoney.com) -- A significant proportion of lipstick manufactured in the United States and used by millions of American women contains surprisingly high levels of lead, the Campaign for Safe Cosmetics said Thursday.

According to new product tests, 61 percent of brand-name lipsticks tested contained detectable levels of lead, which can be toxic if ingested.

The top brands testing positive for lead included L'Or�al Colour Riche "True Red," L'Or�al Colour Riche "Classic Wine," Cover Girl Incredifull Lipcolor "Maximum Red" and Dior Addict "Positive Red," the group said.

The FDA said it is aware of concerns about lead in lipstick and is following up on the report, a spokeswoman said.

"These concerns have not generally been supported by FDA's own analysis of products on the market," the spokeswoman said. "In the present case, we are looking into the specific details of the issues raised."

Federal regulation covers lead levels in lipstick coloring, she said.

An industry representative said the products tested by the CSC meet FDA standards.

"The FDA has set daily safe levels for lead exposure for adults, children and pregnant women," said John Bailey, the executive vice president for the Science Cosmetic, Toiletry, and Fragrance Association, a trade group representing the cosmetics industry. "The agency also has set strict limits for lead levels allowed in the colors used in lipsticks."

In a statement, L'Or�al Group said it "is committed to upholding the highest standards of safety for all the products it makes and sells. Each and every ingredient used in our products has been thoroughly reviewed and tested by our internal safety team."

Procter & Gamble (Charts, Fortune 500), the company that owns Cover Girl, said it follows a "very rigorous scientific process" in evaluating its products and the ingredients used to make them.

"P&G stands behind the safety of our products because of the standards we set and the rigid requirements imposed by our industry," the company said.

A spokeswoman for Christian Dior cosmetics was not available for comment.

According to the Campaign for Safe Cosmetics, one-third of the tested lipsticks exceeded the FDA's limit for lead in candy - a standard established to protect children from directly ingesting lead. Pregnant women and young children are particularly vulnerable to lead exposure.

"Lead builds up in the body over time and lead-containing lipstick applied several times a day, every day, can add up to significant exposure levels. The latest studies show there is no safe level of lead exposure," Mark Mitchell, M.D., president of the Connecticut Coalition for Environmental Justice said in the CSC statement.

The lead tests were conducted by an independent laboratory over the month of September on red lipsticks bought in Boston, Hartford, Conn., San Francisco and Minneapolis, according to the CSC.

The Campaign for Safe Cosmetics, established in 2002, is made up of women's, public health, labor, environmental health and consumer-rights groups including the Breast Cancer Fund, Clean Water Fund and National Environmental Trust.