Lawmakers want shopkeepers to remove e-cigarettes that were not authorized by the F.D.A. Retailers say it is not that simple.

Read More E-Cigarettes, United States Politics and Government, Smoking and Tobacco, Regulation and Deregulation of Industry, Youth, Nicotine, Advertising and Marketing, Food and Drug Administration, World Health Organization, Blumenthal, Richard, Brown, Sherrod, Durbin, Richard J, Sanders, Bernard, Wyden, Ron