Nail polish bottles can be emptied by using acetone or nail polish remover since acetone can thin and break down nail polish.
Nail polish contains ingredients such as formaldehyde, toluene, phthalates, and others. Although these ingredients are not harmful to humans, as long as the nail polish is used as directed, they can cause harm to the environment if they aren't disposed of properly.
Even though they are small glass bottles, empty nail polish bottles can be hard to recycle. Instead of just throwing them away, there are several creative ways to reuse them.