Yeah thats interesting about cookware. Teflon is known to cause health issues in certain contexts: https://www.ecowatch.com/teflons-toxic-legacy-dupont-knew-for-decades-it-was-contaminating-wate-1882142514.html

Interesting though, what studies have been conducted to look at that?

I imagine not many, as pharma will generally not fund studies that could limit profits by proving products unsafe. I imagine in the next few decades there will be many pharma drugs uncovered to be unsafe that were previously thought to be safe. It's just like cigarettes.