• It might be quite the opposite! The study itself concludes that “for individuals with mixed exposures to asbestos, all exposures should be considered”.

    Yes, but the study still shows that people with no environmental exposure still got cancer. It’s still explicitly stating that talc exposure is asbestos exposure. If J&J’s argument is that these researchers made their product look more dangerous than it is by including people with environmental asbestos exposure in their studies – whether by accident, or for nefarious purposes – and therefore creating a false link between talc and cancer, this paper side-steps that issue entirely by including people with and without known exposure, and showing that talc exposure is equivalent to environmental exposure.

    If J&J is saying what I think they are saying, then the researchers made these products look more harmful than they were, and included people who would have been harmed by other exposure to asbestos but concealed that fact in the study.

    Proving that they concealed this information would be difficult, I think, though it would be devastating not only to their bank accounts, but to their careers more generally. Emory, Maddox, and Kradin’s study explicitly states:

    One hundred forty subjects with documented exposures to cosmetic talc were initially reviewed. Exposures were identified through sworn deposition testimonies and answers to sworn interrogatories provided from subjects, parents, and spouses. Sixty-five subjects were excluded due to recalled occupational or paraoccupational exposures to other sources of asbestos.

    So, that wouldn’t even be a lie of omission. It would be straight academic malpractice. Their academic careers would be over.

    • Yes, but the study still shows that people with no environmental exposure still got cancer.

      There’s no denying that asbestos in talc products cause cancer, but the argument is “to what extent”?

      For instance, why doesn’t the study have a control group (i.e. no talc and no other exposure to asbestos)? That would at least give some idea of the risks from using talc compared to no talc use.

      The way the study is set up, it’s like comparing smokers who had a pack a day vs those who had 1.5 packs a day. Where are the non-smokers?

      It seems that the loser in this case would come out severely damaged: on one hand, you’ve got shareholders and a possible countersuit for defamation, and on the other hand you have a career ending outcome. I would hate to be either party!

      • It’s true, the results are weaker than if they had done a comparison study, but a lot of medical research is just post-facto observation reports. Like, to do a proper double blind study here, you’d have to start with healthy people and then knowingly expose some of them to something you suspect may be a carcinogen.

        That’s not going to pass the ethics board.

        You can look at people who have already gotten cancer and try to lump them into those who have used talc-based products and those who haven’t, but then how do you actually measure the impact of the talc there? Do you look at the number of patients who did use talc-based products vs those who didn’t? Those might just reflect the rate at which those products are used among different subsets of the population.

        The key bit here is that the kind of cancer they’re looking at – mesothelioma – is known to be caused by asbestos. It’s also known that talcum powder contains asbestos. So, the observational link here is seeing whether people with mesothelioma have had known significant exposure to environmental asbestos and how much exposure they’ve had to talc-based products. And if you can see in your observations that higher or more prolonged exposure to talc is correlated with increased mesothelioma rates, and can assume that these people – based on their own memories – have not been exposed to environmental asbestos at a rate higher than any other average person, then environmental exposure becomes an independent factor and you can assert the correlation between talc exposure and cancer rates.