Lead is a study in contradictions. It’s dense enough to stop an X-ray, but soft enough to scratch with your fingernail. It’s heavier than steel and iron, but also more flexible.  And, despite evidence of its toxicity, humans have been using it for all sorts of things for thousands of years.  In this edition of our series “The Element of Surprise,” we hone in on this notorious heavy metal. What chemical properties make lead so harmful? How did something so dangerous become so ubiquitous? And if medical authorities acknowledge no amount of lead exposure is safe – especially for children – why do so many of us have lead in our water and our homes? Featuring Justin Richardson, Bruce Lanphear, and Chakena Perry. This episode was produced by Kate Dario. For the full credits and transcript, go to outsideinradio.org.  SUPPORT To share your questions and feedback with Outside/In, call the show’s hotline and leave us a voicemail. The number is 1-844-GO-OTTER. No question is too serious or too silly. Outside/In is made possible with listener support. Click here to become a sustaining member of Outside/In.  Follow Outside/In on Instagram or join our private discussion group on Facebook. LINKS Radiolab dedicated an episode to the scientist that was trying to estimate the earth’s age, and unintentionally helped get rid of leaded gasoline in the process. It’s wild and worth a listen.  A comprehensive history of leaded gasoline and an in-depth investigation of how the lead industry lobbied cities to use lead pipes.  Gerald Markowitz and David Rosner have published numerous books covering the American lead industry and lead’s lasting public health impacts.  The EPA has robust resources about how to deal with lead exposure and how to minimize your risk.  Learn more about your ad choices. Visit megaphone.fm/adchoices