We have mercury thermometers in our first aid kit and also the new digital ones.  No hazard in a mercury thermometer as long as it's intact.
Asbestos removal was a big thing in the 80s. 
Very expensive to have it done.  Hazmat suits, respirators, taken to a special dump 60 miles away, etc.
However, if you knew a guy who new a guy you could get it removed on the down low.
Regular people just couldn't afford to go the $$ route.
Lead paint in the old houses (pre-1970 usually) was also an issue.  Kids would eat the chips, particularly in the poor neighborhoods where the parents didn't watch their kids.
Lookup how cars burning leaded gas affected the population years ago.  They say it lowered IQs by a significant amount due to lead's affect on the brain.

Really? Mold filling the residence?

Sometimes mildew builds up in the shady areas along the outside walls of my house or garage. When it shows up, I hit it with a power washer.

Agreed. I never played with mercury, but I do recall using mercury thermometers. Weren’t there even infamous mercury toys and radioactive science kits? My residence is filled with mold and
Asbestos. It was the way of the olden times.

If you make it past the childhood diseases and avoid accidental death you can live a long time.

I recall playing with mercury as a kid. Not a lot but did it.  Usually got it from thermometers.

Also messed with asbestos my father had laying around.  Seeing if it would burn.

The heating ducts in our house were covered in asbestos.

"Nobody Knows Nuffin"