‘No link between talcum powder and ovarian cancer’
A major US government-led study published Tuesday found no link between ovarian cancer and the use of talcum powder in the genital area, citing data from more than 250,000 women. The paper appeared in the influential Journal of the American Medical Association (JAMA), which also published an editorial praising the research methods and calling the findings "overall reassuring."
For decades, some women have used talcum powder for genital hygiene to absorb odor and moisture -- either through direct application or via underwear, sanitary pads, tampons or diaphragms. The practice is more common among older generations. But its use has grown controversial because of reported cancer risks, reports BBC.
In 2018, US pharmaceutical giant Johnson & Johnson was ordered to pay out $4.7 billion to 22 women who had claimed that asbestos in the company's talcum powder products caused them to develop ovarian cancer. An appeal is underway.
In the 1970s, concerns arose over possible contamination of the mineral talc with asbestos, which often form alongside each other in nature. Some studies showed a higher risk of ovarian cancer among users of talcum powder, which was suspected of entering the ovaries via the vagina and uterus.
But the link remained contested because of the overall low number of studies conducted, with some of them criticized for a methodology that introduced recall bias among participants, while others were not statistically conclusive. The effect is also difficult to isolate because ovarian cancers themselves are rare: only 1.3 percent of all women risk being affected in their lifetimes.
In the new JAMA paper, led by Katie O'Brien of the National Institute of Environmental Health Sciences, researchers synthesized data from four large studies, which encompassed data from a quarter of a million women from 1982 to 2017.
The studies surveyed participants every year or two on a diverse set of questions related to health, including the use of talcum powder. The hope was that by scaling up the number of participants, it would be possible to discern weak effects with statistical validity, which would have been undetectable on a smaller population.