Anything can be harmful to the environment - cities, farming, resorts, chemical industries - if not constructed and operated properly.
Chemical industries get a bad rep as they handle truly nasty materials that are poisonous and persistent. However, the majority of times there is no harm as proper controls are in place. When there is an incident it gets a lot of publicity.
This is similar to plane crashes and landslides - no one cares about them most of the time, but when something happens, it's bad and newsworthy.
Chemical industries are essential to maintaining our way of life - they make antibiotics, fertilizer, paints, plastics, fibers. Like so many things the risk and the benefit must be understood and managed.