The annual E-Cigarette Summit in Washington, DC, is perhaps the most eclectic conference in tobacco control. Consumer advocates, vape shop owners, academics, [...] all gathered on May 17, as they have for the past several years.

Perhaps more than anything, the conference is a rare opportunity to publicly levy questions at higher-ups in the Food and Drug Administration (FDA), an agency not known for its transparency. So it didn’t take long for attendees to rise during the Q&A sessions and ask [...] why the FDA has continued to communicate so poorly the “continuum of risk”—the idea that some nicotine products are significantly safer than others.