The average menstruating person will spend about five years of their total reproductive lifespan using an estimated 11,000 tampons, sanitary pads, panty liners and other menstrual products, experts say. What if some of those menstrual aids contain heavy metals or potentially toxic chemicals linked to chronic diseases and reproductive and developmental problems? Past research has found tampons and other menstrual products may contain chemicals such as perfluoroalkyl and polyfluoroalkyl substances, or PFAS; plasticizers, also known as phthalates; and volatile organic compounds, or VOCs, emitted as gas or fragrances from many consumer products. All these chemical groups have been shown to disrupt the body’s endocrine system , which regulates sexual development, metabolism, blood sugar, mood, sleep and more.

Recently, a small pilot study found arsenic and lead in organic and nonorganic tampons — and while the levels were small, there is no safe level of exposure to lead, according to the U.S. Environmental Protection Agency .

However, that study was unable to determine whether heavy metals might leach from tampons into the body, thus making any potential health impact unknown, said senior study author Kathrin Schilling, assistant professor of environmental health sciences at Columbia University’s Mailman School of Public Health in New York City. “I do not want people to panic, but to be aware that heavy metals have been found in these menstrual products,” Schilling said.