Having more than passing familiarity with this, the mechanisms to close down a factory due to pollution are long, agonizing, expensive for the city and its people, and unlikely to succeed.

Part of this is an ever moving, never quite enough demand for "actual studies" and evidence. If you provide an epidemiology study, they'll demand clinical trials. Clinical trials? Not generalizable, bring on the epidemiology. But you haven't done a proper toxicology study....