Coast to coast, cities are feeding dangerous misperceptions and making it harder for smokers to quit.Today, cigarette smoking remains the No. 1 cause of preventable death in the United States. So why are cities and towns coast to coast taking harm-reduction alternatives off the shelves while allowing Marlboros to remain?

Last month, San Francisco banned the sale, including the online sale, of e-cigarettes. Around the same time, Brookline, a Boston suburb, did the same thing. Livermore, Calif., followed suit. Also moving in this direction are Morristown, N.J., Blufton, S.C., and Seattle.

With an uptick in teen vaping, parents and residents are understandably worried about our youth picking up a bad habit. But in their eagerness to tackle one problem, these municipalities are revealing a deep misunderstanding of vaping, ignoring the unintended consequences of bad policy, and putting many more lives at risk.

As the FDA acknowledges, nicotine “is most harmful when delivered through combustible tobacco products.” Vaping doesn’t release the toxins that come from burning tobacco and that lead to lung cancer, emphysema, and heart disease. By itself, nicotine is addictive — but not toxic.

As a result, Public Health England considers e-cigarettes 95 percent safer than traditional cigarettes for adult smokers; and in 2015, Britain’s Royal College of Physicians stated that e-cigarettes are “likely to be beneficial to public health.” In fact, the U.K. views e-cigarettes as so much better than traditional smoking that several hospitals there are now providing them as a part of their anti-smoking efforts. What’s more, The New England Journal of Medicine published British research finding that smokers who use e-cigarettes are twice as successful at quitting as those who rely on other approaches. And now a similar American study has arrived at the same result: Daily e-cigarette use “was associated with a 77% increased odds of prolonged cigarette smoking abstinence over the subsequent two years.”