Reasons why we love our Rainbow Bamboo Toothbrushes : they are made of sustainably sourced MOSO bamboo, which is not only an amazing eco-friendly resource, but is also clean on both the micro (BPA-free) and macro (biodegradable) levels. The soft wave bristles clean your teeth gently and efficiently for a healthy smile.We give back : 10% of the profits from Rainbow sales go to social and environmental causes.The American Dental Association recommends changing your toothbrush every 3 months. Bamboo can change color over time, which is completely normal.Children should be supervised at all times while brushing their teeth. Do not let your child bite or chew on toothbrushes.