Are mice droppings and urine toxic?
I live in a country house and the basement is insulated from the ground floor with pink insulation. Over the years, there have been several mouse infestations in the basement, between the suspended ceiling and the mineral wool. They dug holes in the wool and left a lot of feces. I would like to know if their traces are toxic for humans, and would you recommend changing the insulation?
Yes, the presence of mice and their droppings is definitely a health risk for humans. Mice sometimes carry dangerous viruses (hantavirus) and humans can contract it by breathing in particles contaminated with excrement, urine and saliva from infected animals. Here is our page about preventing rodent and insect infiltration -
How to get rid of insects & rodents safely & humanely
And yes, we would strongly recommend removing the contaminated insulation, but that is a job best done by professionals to avoid adding contaminated dust to the air and surfaces of your home. After removing the insulation and before reinstalling new insulation, be sure to do a thorough cleaning.
When all the contaminated insulation is removed is the time to find where they are getting in and take measures to seal those openings to prevent it from happening in the future.
Before you begin re-insulating, note that pink fiberglass insulation is not the ideal insulation for crawlspaces or basements, as it is susceptible to moisture damage. EPS rigid foam boards or Rockwool would be a better alternative. Both are more suitable for potentially humid environments, and Rockwool in particular is made with recycled stone dust, that would be our preference.