Urine stains on plastic toilet seats are problematic and embarrassing. Scouring cleansers will permanently scratch the surface of the toilet seat and leave most of the stain behind. Chlorine bleach will kill the germs but will hardly put a dent in the discoloration that urine leaves. Consider a safer, gentler way to remove the yellow and brown buildup. Baking soda paste and a little elbow grease removes this unattractive sight, leaving a clean, fresh appearance.
Spray a germ-killing cleaner, such as Clorox Clean-up, on the toilet seat stains. Let the product sit on the surface for 5 to 10 minutes. Wipe the area with a damp rag.
Mix ¼ cup of baking soda with ½ cup of warm water in a small bowl. It should have a paste-type consistency. Smear this mixture onto the stained areas, and let it sit for 15 to 20 minutes.
Use a scratch-free scouring sponge dipped in water to scrub the stained toilet seat. Scrub in a circular motion, wetting the sponge periodically.
Reapply paste on stained areas, and repeat scrubbing until the yellow/brown stain is gone. Rinse well with clear water.
Spray the surface again with Clorox Clean-up (or a similar germ-killing cleanser), and wipe with the damp rag. This will give the toilet seat a fresh look and smell.