I’m rummaging in my make-up bag, checking the ingredients of face powders, eyeshadows and blushers. The reason I’m covering my rug in sparkly beige powder is that these products containing talc could also have traces of something that shouldn’t be there, something deadly: asbestos.The spark for this interest was Hannah Fletcher, 48, a mother-of-two from Oxshott, Surrey, and once a City high-flyer. In 2017, she was diagnosed with mesothelioma, a cancer that had affected the lining of her abdomen. It’s hard to treat and, once diagnosed, 55 per cent of patients die within a year. But Fletcher’s doctors also advised her to call a lawyer, as mesothelioma is almost exclusively caused by exposure to asbestos. When her cancerous tissue was examined, a pathologist concluded that, in their opinion, Fletcher’s cancer was caused by exposure to asbestos in her talc-based cosmetics. She decided to sue the US companies that made her favourite products. The judgment in the New York case named these as Avon, Estée Lauder and Clinique. On the eve of her trial in 2020, the companies offered Fletcher a settlement, although she can’t tell me how much as she has signed a non-disclosure agreement. ‘Dozens’ of lawsuits in the US have now been filed by British women against cosmetics companies, says Fletcher’s lawyer Harminder Bains, a partner at the London firm Leigh Day. Bains has one case set for trial next year, while other law firms have cases set for trial later this year. The reason these are being brought in the US, says Bains, is that ‘the way the current law stands in the UK, it would be difficult to succeed with these cases [here]. The law in the US [makes it] easier to succeed in these cases.’ Fletcher believes it was important to take action: ‘It felt like all this trauma and horrific impact on our lives had been so unnecessary. I’m really angry, because my life has been devastated.’As part of my investigation for the BBC Radio 4 podcast Talc Tales, which came out in the summer, I found that talc is used in powder-based cosmetics to ensure they glide on smoothly and to stop them caking (check your product labels for talc, talcum powder and/or magnesium silicate). It’s also a main ingredient in talcum powder, which women have historically been encouraged to pat on their babies’ bottoms or their own perineum. This naturally occurring deposit is often found with asbestos minerals in the ground. Both are formed under similar conditions and made of the same chemical elements. So if you have talc in the earth, you could have asbestos, too.Asbestos can cause deadly diseases as it breaks down into microscopic fibres that can easily be inhaled. Owing to their long, thin shape, the fibres penetrate deep into the lungs and beyond. As the fibres can’t be broken down by our bodies, they remain, eventually causing lung cancer or mesothelioma.The issue of asbestos contamination in talc has been discussed at cosmetics companies as far back as the 1970s, but only became a public scandal when it made its way to the courts in the 2010s. Hannah, whose mesothelioma was diagnosed in 2017, sued three beauty brandsBack in the 70s, Johnson & Johnson had the lion’s share of the talcum powder market. It owned its own talc mines, and the sweet-smelling Baby Powder was in bathroom cabinets around the world. But internal memos appear to show that the company was aware of asbestos being found in its talc supply tests from at least 1971 to the early 2000s. Three independent labs tested samples and had all found asbestos fibres. Then, in 1973, Johnson & Johnson’s head of research went to its mines in Vermont and reported that in the talc, ‘occasionally, sub-trace quantities of tremolite or actinolite are identifiable. And these might be classified as asbestos fibre.’When I put this to the company, Johnson & Johnson told me ‘one of these tests did show less than 1/100th of one per cent asbestos in the material’ but that ‘the testing was “hectic”’ and ‘the findings couldn’t be replicated’.Many more internal memos were examined during a court case launched in the US in 2018, when 22 women and their families alleged that Johnson & Johnson’s talc products caused them to develop ovarian cancer. They all regularly used talcum powder on their genitals and they were all seriously ill. Some died before the end of the trial. The jury found Johnson & Johnson’s talcum powder products did contain asbestos and that the company had failed to adequately warn users of the risk of harm posed. The jury found this failure caused or directly contributed to the deaths, or the cancers affecting, the 22 women. The company was ordered to pay around £1.5 billion in punitive damages – one of the biggest pharmaceutical payouts of all time.Johnson & Johnson eventually stopped using talc in its Baby Powder in 2023 but still maintains the product was safe, saying sales were declining due to ‘misinformation around the safety of the product, and a constant barrage of litigation advertising’. The company told me, ‘Allegations that our talc could pose harm to consumers is a concern that Johnson & Johnson took very seriously. Time and again, the independent testing proved that Johnson’s Baby Powder was free of asbestos.’Earlier this year, I sent newly bought versions of eight make-up products I use that contain talc – from expensive blushers and bronzers to high-street eyeshadow – to Brunel University’s Experimental Techniques Centre in London for testing. Using the most sensitive microscope, the scientists found one asbestos fibre in each sample from a dry shampoo and an eyeshadow palette. I was told at least three fibres have to be found to confirm the asbestos came from the make-up, despite having strict protocols to ensure its lab wasn’t the source of the contamination.This isn’t the first test of its kind. In 2021, the UK government’s Office for Product Safety and Standards (OPSS) ordered tests of 60 low-cost eyeshadows and face powders and 24 ‘child-appealing’ make-up products. In one of the latter, an asbestos fibre was found, and two of the low-cost samples had three and five asbestos fibres. The OPSS told me, ‘The levels found during the tests did not demonstrate a breach of the Cosmetics Regulation.’ Bains says, ‘There is no safe level.’ The law governing cosmetics is vague. In the UK there is no regulation setting out how talc-based cosmetics should be tested for asbestos; the industry’s voluntary standard is based on a testing method drawn up in 1976. Unfortunately, says geologist Sean Fitzgerald, it’s not sensitive enough to catch all the asbestos fibres that might be in the talc: ‘The problem we identified is that it takes tens of thousands of asbestos fibres to get a response using this testing method.’But still, these tests find only trace amounts of asbestos fibres in cosmetics. Do these low levels pose a health risk? Dr Astero Klampatsa, mesothelioma and lung cancer immunologist at the Institute of Cancer Research in London, says we don’t know how many asbestos fibres it takes to cause cancer. ‘Cases have occurred even with brief or low-level exposures to asbestos. The only real way to say that we are in a safe level is if we have no asbestos exposure at all.‘So using a beauty product that might contain one fibre of asbestos poses minimal risk. If we say that one uses this product over time continuously, then this risk increases, because it’s cumulative. However, even with these multiple uses, the overall risk remains very, very low. Saying all that, I would advise avoiding any unnecessary exposure. I would choose a talc-free product.’ But this advice came too late for Hannah Fletcher, whose cancer has now spread and can’t be treated.Estée Lauder, which also owns Clinique, denied liability and said, ‘The Estée Lauder Companies is committed to selling safe products – we only use talc that is tested and certified as asbestos free.’ Avon told me, ‘Any talc used by Avon is the highest quality cosmetic grade and has been tested to confirm that it does not contain asbestos.’Bains is currently working on dozens of similar cases. ‘What really needs to be hammered home here is that it’s not just talcum powder. It’s in cosmetics like blusher, face powder, eyeshadow,’ she says. ‘And it wasn’t just in products many years ago. It’s in products now.’How They Made us Doubt Everything: Talc Tales is available now on BBC SoundsSarah M Lee/Eyevine, Getty Images