Tear gas is wrecking periods, French activists say, and they want it banned

A French collective called Lacrymos du sang — tear gas of blood — says it has gathered thousands of testimonies from protesters and bystanders who blame police tear gas for unusually painful periods, cramping and off-schedule bleeding. The group, made up of activists and health workers, plans to publish its findings on November 17, though some accounts are already posted to its Instagram. One 20-year-old, Maëva, described periods ten times more painful than usual the day after being teargassed; another, Camille, reported severe pain and heavy bleeding just two days after her period had ended.

The scrutiny lands on a protest movement that has rocked France since September. On October 17 alone, police fired 22,000 canisters, many of them before peaceful rallies turned into some of the worst rioting and looting in years. Earlier in the movement, a canister fired at close range shattered the jaw of 14-year-old Eden in a Paris suburb, leaving him largely toothless and eating through a straw. Investigators are also looking into the death of a 59-year-old man whose family blamed tear gas exposure, after an autopsy found acute cardiorespiratory failure.

The French effort was inspired by research out of Portland after the 2020 Black Lives Matter protests, according to midwife Johanne Voahangy-Nirina, who is part of the collective. That survey of 2,200 people found more than half reported cramping, heavier bleeding and other health problems after tear gas exposure, sometimes lasting for days, and it was the first peer-reviewed study to confirm a link between the gas and abnormal menstruation. Transgender people taking testosterone, which normally stops menstruation, told Oregon Public Broadcasting that cramps and bleeding returned after exposure.

Voahangy-Nirina said the collective hoped to match or beat the Portland sample size but did not expect more than 10,000 testimonies within weeks. She said several women who never attended a protest — people who simply lived, shopped or walked their dogs nearby — also reported unusually painful periods, which she argued means stress alone cannot explain the pattern. She added that the chemical's indiscriminate reach extends to women police officers too.

Scientists are still piecing together why. Solenne Rougeux Fernandez Garcia, a doctoral researcher in neuroendocrinology at Paris-Saclay University and a member of Lacrymos du sang, said the CS compound in most tear gas, including the type used by French police, breaks down into molecules that include a thyroid endocrine disruptor. The UN High Commissioner for Human Rights warned in 2020 guidelines that tear gas in large doses can cause tissue necrosis in the respiratory and digestive tracts, pulmonary oedema and internal bleeding. Amnesty International has documented more than 500 cases of tear gas misuse worldwide since 2018, some in France, and flagged weak regulation of its composition and poor training for officers who deploy it.

For now, protesters are adapting. Student Zon, 24, said the days of carefree marches are over: people now arrive with scarves, masks, goggles and eye drops. Her friend Val, 23, said several friends had complained of pelvic pain and unusually painful periods after exposure at earlier protests, and credited online platforms and independent media with keeping the issue visible. All eyes now turn to the collective's November 17 release — and to whether it shifts the debate over a weapon France insists is less-lethal.