Science Friday 2021-07-23 Share Share this on Facebook (Opens in a new window) Share this on Twitter (Opens in a new window) Share this via Email Surgeon General, Blockchain. July 23, 2021, Part 1 Shellfish Deaths, Chemical Safety, Humpback Songs. July 23, 2021, Part 2 Hosted by Ira Flatow and John Dankosky Produced by Science Friday and WNYC Studios