Mythbusters tested storing toothbrushes outside the bathroom and found it doesn't really make a difference. https://go.discovery.com/tv-shows/mythbusters/video

Mythbusters tested storing toothbrushes outside the bathroom and found it doesn't really make a difference. https://go.discovery.com/tv-shows/mythbusters/videos/surprise-toothbrush-minimyth https://go.discovery.com/tv-shows/mythbusters/videos/surpris...