In 2011, NPR correspondent Howard Berkes noticed an anomaly in the sidebar of a government report on the Upper Big Branch mine disaster in West Virginia. It suggested that there was an extraordinarily high rate of black lung disease among the coal miners who'd been killed in the explosion. And it set him on a decade-long investigation to understand the cause of a hidden epidemic, the toll it took on miners and their families, and why government agencies had failed to prevent it.
You can find more of Howard's landmark reporting on black lung disease on the episode page.
