Contributing Correspondent Dennis Normile talks about a long-term study involving the survivors of the Hiroshima and Nagasaki bombings. Seventy-five years after the United States dropped nuclear bombs on the two cities in Japan, survivors are still helping scientists learn about the effects of radiation exposure. Also this week, Sarah talks with Winnie Lau, senior manager for preventing ocean plastics at Pew Charitable Trusts about her group’s paper about what it would take to seriously fight the flow of plastics into the environment. This week’s episode was produced with help from Podigy. Listen to previous podcasts. About the Science Podcast Download a transcript (PDF).