When you want to remove mildew stains, reach for white vinegar first. It can be safely used without additional ventilation and can be applied to almost any surface –bathroom fixtures and tile, clothing, furniture, painted surfaces, plastic curtains, and more. To eliminate heavy mildew accumulations, use it full strength. For light stains, dilute it with an equal amount of water. You can also prevent mildew from forming on the bottoms of rugs and carpeting by misting the backs with full-strength white vinegar from a spray bottle.