The impact and use of lead by romans has has been debated, but there is indication that they used lead cookware, although admittedly more for wine than food.
They also used it for their water piping which wasn’t too good. Then again, looking at what’s going on, it is an interesting question if we can rule out some similar effect for the weird decline of previously sane people like the former Mayor of New York. They may have been assholes all along, but it’s also clear that so thing changed.