March 15, 2011 11:20 pm Could Japan's Radiation Be a Threat Here? A local specialist sorts through the facts and myths on radiation and explains potassium iodide tablets. US & World Videos 8:59 Raise a julep to the Kentucky Derby: The Lineup 0:32 Five people arrested in 2006 Philadelphia cold case 0:19 Body of missing kayaker found in the Schuylkill River 2:00 Police officer placed on administrative duty after killing dog that attacked a man 0:51 Police officer shot and killed 1 of 4 dogs that attacked a 53-year-old man