landlord negligence/health issues

My family has been in the same rental unit for the past six years. Shortly after we moved in, the water heater was replaced by the on site maintenance person.
Just a couple of months ago, after a township inspection of rental units, we learned that our gas water heater was never properly vented at installation. Both of my children have suffered from nosebleeds each winter, which my husband and I had attributed to "dry, winter air". Both my son and myself have chronic sinus issues, which we have attributed to indoor and outdoor allergies.

From what I've learned by searching online, an improperly vented gas water heater can be quite dangerous and harmful to one's health. Although the water heater is now properly vented, do I have any recourse against my landlord if any of my family's health problems are attributed to at some point to the water heater?