For years, Boston University School of Public Health Professor Dr. Michael Siegel has been skeptically questioning a particularly ominous allegation regarding the dangers of secondhand smoke. According to ASH (Action on Smoking and Health) and other groups, "Even for people without [certain] respiratory conditions, breathing drifting tobacco smoke for even brief periods can be deadly. For example, the Centers for Disease Controls [CDC] has warned that breathing drifting tobacco smoke for as little as thirty...