If a paper towel is thrown away, it will usually biodegrade, especially if it’s not coated with chemicals or plastic. Since it’s made from paper, it breaks down naturally in the environment within a few weeks.However, if it’s thrown into regular trash and goes to a landfill, it may take longer to decompose due to lack of air and moisture. It’s better to compost used paper towels (if they don’t have chemicals) so they return to the soil safely.