Money's not a universal solution. But in this particular case it would help. If re plant owners had to pay for the damage they inflicted on those around them, then given a choice between a site where they had to pay because people were there and a site where they did not have to pay because people were not there, what would they choose?

Also, enforcing economic solutions does not necessarily prevent adding other non economic solutions. For an economic activity, such as production of these chemicals, economic solutions can go a really really long way to bettering behavior.