Reports of lung injuries from e-cigarettes splash across the news these days, but the nicotine-delivery devices are also spawning a quieter worry: whether users risk long-term health effects that may not manifest for decades. Studies in animals and people are now starting to probe whether e-cigarettes pose chronic risks to the lungs and cardiovascular system.

E-cigarettes are battery-powered devices containing nicotine and other substances, such as solvents that dissolve the nicotine and flavorings that enhance their appeal. Heat converts the mix into an aerosol that users inhale. Manufacturers tout e-cigarettes as tools to help smokers quit, although data are mixed. But one thing is clear: Millions of young people who didn’t smoke cigarettes have taken up vaping. And given that e-cigarettes vary more than conventional cigarettes in their chemical composition, “We’re asking medical science to do a huge, heavy lift” to pinpoint health impacts across people, says James Stein, a preventive cardiologist at the University of Wisconsin in Madison.

He and others believe they have no choice but to try. This month, the National Heart, Lung, and Blood Institute gave a boost to studies of acute and chronic effects when it announced supplemental funds for ongoing e-cigarette research, on which the institute will spend $23 million this year.

Source: American Association for the Advancement of Science

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