An occupational health and safety clinic in Windsor, Ontario, expressed its concerns about the health of former workers at a foundry and insulation plant in Sarnia to the Canadian Auto Workers union early in 1998. The workers suffered cancer, respiratory and hearing problems, and heart disease. An investigation of their workplace exposures ensued. Researchers obtained government documents that showed the history of ineffectual regulation at Sarnia and some of the highest levels of asbestos--hundreds of times over the legal limits--ever recorded in Canadian workplaces.