E-cigarettes are replacing real butts with those that have battery-powered cartridges and emit a vapor mix of nicotine and water. According to proponents, they’re odorless, help smokers quit and don’t expose people to secondhand smoke. But as Seyfarth Shaw associate Sara A. Eber explains on the Employment Law Lookout Blog, U.S. health officials and legislators aren’t ready to give e-smokes the green light.

Although scientists agree they have less nicotine than traditional cigarettes, experts say there’s no way to tell what the long-term side effects will be on users and third parties. The U.S. Food and Drug Administration expresses similar concerns and plans to propose new rules to regulate them soon.