Tip of the week: Close the lid by DrSteakleyDDS • June 6, 2013 You should not keep your toothbrush near a toilet. The airborne particles from the flush can travel up to a distance of 6 feet. Yuck! If you have a small restroom, the best you can do is close that lid when you flush! Remember to change out your toothbrush every three months or after an illness.