E-cigarettes help smokers kick the tobacco habit, but are they safe?

E-cigarettes are far from universally accepted as a public health tool; regulators are agonizing over whether to restrict them as “gateway” products to nicotine addiction and tobacco smoking, or embrace them as treatments for would-be quitters. A big issue is the lack of long-term scientific evidence to support the safety and effectiveness of e-cigarettes, prompting critics to warn of the dangers of their unregulated use. Read more here.