A study by state and federal health officials say it’s safe to live near the nation’s largest lead smelter. A two-year study of people living near the Doe Run Smelter in Herculaneum finds they are not exposed to unhealthy levels of arsenic and cadmium, which are suspected cancer causers. The Missouri Department of Health and the federal Registry for Toxic Substances and Disease have studied urine samples for two years. Some trace amounts of cadmium have been found on fruits and vegetables grown near the smelter. But they say it’s okay to eat them occasionally if they’ve been cleaned thoroughly.