How to Sanitize and Clean Plastic PET Bottles

PET or PETE plastic, also known as polyethylene terephthalate, is used to make bottles for everything from carbonated beverages to salad dressings and shampoos. It's recyclable as well as reusable, but reuse requires careful cleaning and sanitizing first. Wash bottles as you would any drinking glasses, and then they're ready to sanitize with a mild bleach solution.

Rinse out any residue or liquids originally stored in the PET plastic bottle, then wash the bottle in hot, soapy water as you would with dishes, drinking glasses, or food storage containers. Use a scrubby sponge to remove anything caked and dried inside the bottle, or simply let the bottle soak for at least 10 minutes to help loosen the material before scrubbing. A bottle brush also helps for hard-to-reach areas.

Whenever washing PET or any type of plastic, it's a good idea to let the item dry completely before filling it with another substance or before placing the lid back on the bottle to help prevent bacterial growth. Though PET may be reused indefinitely, it's best not to reuse PET bottles with scratches inside, as those scratched areas could harbor bacteria.

PET plastics are the type with a triangular recycle symbol on the bottom, with the number 1 in the center of the symbol. Even though PET plastics are safe for food use and are one of the most common plastics used for food packaging, it's best to not place foods or beverages in PET plastics that once held chemical products that aren't meant for consumption, just in case any residual product is still in the bottle.

Sanitizing kills or removes germs still lingering after washing the bottle, while cleaning generally removes dirt and debris, but not necessarily germs. Sanitizing doesn't kill viruses, while disinfecting does, but disinfecting usually involves chemicals. Disinfecting generally isn't necessary in normal circumstances, but sanitizing keeps the plastic safe for storing beverages.

To sanitize PET plastics, or virtually any glass or plastic suitable for holding beverages or foods, rinse the item in a mild bleach solution of 1 teaspoon bleach per quart of water. Let the bottle air dry before replacing the lid or adding anything to the bottle. If the bottles were somewhat dirty before, let them soak for 10 minutes or so in the bleach water. If desired, put the lid on the bottle with the bleach solution in it, shake the bottle gently, then dump the liquid out.

Though regular washing of a water bottle is enough to keep it clean enough to use for workouts or while at work, it's a good idea to sanitize it at least once per week. For plastic that smells musty or if you see mildew or mold in the bottle, soak the bottle in the bleach solution for several hours once you've washed and rinsed it out. Even if you use the PET plastic bottle to store water for plants, it's a good idea to keep the bottle as clean as possible so the water within it stays clean.