Can wearing your shoes inside your house make you sick?
A study at the University of Arizona found that on average there are 421,000 bacteria on the outside of shoes! The bacteria included E. Coli, which can cause intestinal infections, Listeria, which can cause problems for pregnant women, Klebsiella which can cause urinary tract infections, and Serratia ficaria, which can cause respiratory infections. One study found that 24% of all shoes had E. Coli present!
In addition, toxins are brought in on your shoes. A study found at Baylor found that people who lived near asphalt roads that had been sealed with coal tar have an increased risk of cancer, presumably from the toxins. Other toxins tracked inside included gasoline, pesticides and fertilizer from lawns.