Rep. Carolyn Maloney, D-N.Y., introduced a bill on Wednesday that would require the National Institutes of Health to research whether menstrual hygiene products that contain chemical additives like chlorine and fragrances are health risks. The Robin Danielson Act of 2014 would ask the Federal Drug Administration to monitor and publish information on the presence of these contaminants in a broad range of products such as pads, liners, cups and sponges used by millions of American women.

“American women spend over $2 billion per year on menstrual hygiene products,” Maloney said. “This bill will help determine the health effects of the entire range of hygiene products and provide women with the information they need to make informed choices.”

About half of the U.S. population uses menstrual hygiene products, but consumers are kept in the dark about what’s in them. For a product so intimately connected to women’s health, advocates say that the lack of disclosure of what’s in these products could pose a danger.

“Internally worn products, such as tampons and cups, are worn in the most absorbent part of the body, off and on for literally decades, yet there is a paucity of independent research that addresses the potential risks associated with these and other menstrual products,” Chris Bobel, a public health advocate and author of “New Blood: Third Wave Feminism and the Politics of Menstruation,” said in a statement after Maloney introduced her bill.

It is the sixth time that Maloney has proposed the bill, named for a victim of toxic shock syndrome (TSS), a rare, life-threatening bacterial infection afflicting menstruating women using high-absorbency tampons. This time, however, the tide could be slowly turning, with activists launching a global conversation on menstruation.

The bill was introduced a day after health activists celebrated the first global Menstrual Hygiene Day to combat the stigma that’s attached to women’s periods and improve menstrual hygiene. The statistics are devastating. One in three women lacks access to safe washing facilities and sanitary products, according to the World Health Organization, resulting in girls missing many days of school when puberty hits. They also develop higher rates of cervical cancer likely because of poor hygiene.

The Society for Menstrual Cycle Research, a nonprofit organization that works with Maloney, said the legislation pushes for transparency on the chemicals used near some of a woman’s most absorbent and sensitive tissues. TSS sparked a wave of concern in the late 1970s, but a subsequent response regarding the use of chemicals remains lacking.

When Johnson & Johnson temporarily discontinued multiple lines of o.b. tampons in 2010 and permanently removed its extra-absorbent line from distribution, it refused to provide any information on the reasons behind its decision.

Ingrid Johnston-Robledo, president of the research society, said the connection between certain menstrual hygiene products and consumers’ accounts of irritation, yeast infections and bladder infections have not been sufficiently investigated.

There are “all kinds of rumors that we need to get on the bottom of,” she said. “[But] we need to be careful about not spreading the word that tampons are evil.”

Researchers at the Canadian Medical Association reported in a 1996 study that contact dermatitis was linked to the use of Always sanitary napkins. The Campaign for Safe Cosmetics, an advocacy group, warns of the danger of accumulated exposure to toxic chemicals, such as dioxins, which are used to bleach tampons and make fibers look white. Dioxins are carcinogens and have been linked to endometriosis and disruptions of the hormone system, according to the campaign.

Other disruptors include pesticides, used to grow nonorganic cotton, and fragrances, whose composition are considered trade secrets but have been known to contain harmful chemical substances such as phthalates.

“There are many who believe that the multibillion dollar menstrual hygiene industry will regulate itself, and because the potential risks associated with these products are not front page news, it’s easy to believe that there isn’t a real problem that needs to be addressed,” Maloney said. “That’s why it’s important to continue raising awareness.”