My tenants have pre-exisiting health issues so I think it would be in my best interest to tell them ASAP and let them know I'm releasing them from their lease and that they will need to be out by the end of the month. 

But we do have a County Health Department that deals with mold claims.

I already pay for their kids schooling (property taxes), section 8, health care and food stamps with the 100K a year I pay in federal income tax a year.Apparently some people are bad at economics.

If you feel the home is causing you health problems, I recommend you move to another rental where you can feel safer.

The intent was to maximize small businesses' ability to maintain liquidity, retain their employees and recover from this health crisis as quickly as possible. 

I purchased under my name in cash because the agreement was time sensitive given the seller’s declining health and offer deadline.

I operate a couple recovery homes, and work with people who have mental health issues.

Since the city is involved you can try and get the health and safety department  (might be the same as building) involved and they may find the home to be in such poor shape that the tenants need to leave. 

Could I be liable for any health issues (real or perceived) that may arise with future tenants?

I think if there is any possibility of it create a health hazard (even a small one) I would address immediately.