Scientists keep warning us, common chemicals we're all exposed to — in food, cosmetics, hygiene products, furniture — are altering our hormones and spurring diseases. Much like visible pollution, exposures are disproportionately harming vulnerable communities. So why do US regulators say there’s nothing to worry about? Get a primer on this terrifying class of chemicals and the scientific controversy around them. Go home prepared to report on this grand experiment taking place on all of our hormones and health.