I've done a lot of cross-country exploring of the USA by motorcycle in the past, and it always shocked me how obviously harmfully polluted the air can be in residential areas neighboring industrial activity.

I don't understand how it continues unchecked. Sometimes I'd spend as little as an hour breathing the stuff and my nose and throat would be sore for days afterwards.

My assumption is the residents are too poor so they lack representation and likely are employed by the same companies behind the pollution. The government should be more actively monitoring these industrial activities and protecting its citizens from their negligence.