Ignoramus15604 fired this volley in
:

I believe, strongly, that mercury is demonized way beyond its actual
harmfulness, due to allowable concentrations becoming ever more
stringent. You can actually count the people damaged by merciry, by
hand.

It was once a much larger problem. So-called "mad hatter's disease" was
caused by continual exposure to mercury compounds.

As Ed suggested in another reply, it has a nasty tendency to accumulate
at the top of the food chain.

It CAN be chelated and removed from a living body, but it's a difficult
and lengthy process.

Lloyd