Contaminated nail polish can lead to a fungal infection, yes. Anyone who used it on toes that were already infected would have transferred the nail fungus to the brush and into the solution. Often polish seals the tissue and can encourage fungus-friendly environment as well. So it isn’t atypical for someone to remove their nail polish and discover an infection has developed. The experts here at Dallas Podiatry Works recommend an antifungal polish that can help slow the growth of these germs in the nail tissue. You should also thoroughly disinfect all of your pedicure tools after every use.