So people kind of knew asbestos was harmful wayyy before it mostly stopped being used in 1979 (USA). But, it was still used constantly in many industries and ended up everywhere. What do you think is an example of something we find out is DRASTICALLY harmful 10-50 years from now? My guess would be screen time.
To be fair, asbestos is still all over the place. They did this fun thing where they just reclassified different asbestos structures into different categories and banned some of them.
My guess for another substance that isn’t asbestos will be either PFAS or we’ll finally find out what all these micro/nanoplastics are doing to us.