Can I use vinegar and baking soda to kill mold in my cooler?

Yes, white vinegar kills most mold species and baking soda scrubs without scratching plastic. Apply undiluted vinegar for 10–15 minutes, scrub with a baking soda paste, rinse with hot water, and dry completely. For musty smells, repeat and leave the lid open in sunlight. Avoid mixing bleach with vinegar.