They also observed that we pee pretty much all the mercury we ingest, but that methyl-mercury is the one we absorb, accumulate, and that is highly toxic.

Removing the filling seems like a great way to inhale more of the stuff. How do they prevent that from happening?

I had one removed about 7 years ago. The dentist fitted a dam to avoid fragments being ingested and to minimise vapor inhalation, and (if I recall correctly) he advised me to breathe as gently as possible during the crucial stage of removal.

> Dentists fought for quite a while but I don't think they are in use anymore.

The anti-dentites won.

I think the dentists are still in use :-)

The dentists fight it because the science mostly says they’re harmless. Trust me, there’s plenty of money to be made removing the old fillings (which actually is the most dangerous time for mercury contamination) and replacing them with composites. Dentists are incentivized to do so. They just don’t want to cause unneeded hysteria.