The toxic styrene leak near Cincinnati is one of many chemical spills that have polluted the air or water in or near Ohio. Here's a look at some others.

A train car in Whitewater Township, Ohio, was discovered to be leaking styrene, which is used to make plastic and fiberglass and is highly flammable.

Residents in an Ohio community where a dangerous chemical leak occurred have been allowed to return to their homes. An evacuation order was issued shortly after styrene, a toxic and flammable chemical that is used to make plastic and rubber,