Mike Kasavich, a lifelong coal miner, exits "the hole" after a 10-hour morning shift at the Mathies coal mine in western Pennsylvania. Black lung disease is increasing among miners, yet they are struggling to get disability reimbursement for the illness. Spencer Platt/Getty Images hide caption

itoggle caption Spencer Platt/Getty Images

Dan Gates, with Albuquerque's Air Quality Division, measures pollen in the air. Despite a 1994 city ban on trees like mulberry, elm and cottonwood, residents have to wait decades for existing trees to die before pollen levels likely will go down. Jeff Brady/NPR hide caption

itoggle caption Jeff Brady/NPR