The U.S. Food and Drug Administration believes the popular electronic cigarette alternative poses some kind of danger to its users, but the evidence it has to back up that claim is rather slim.

The FDA pointed to the 50 times over the last year when users complained to the FDA that they were injured in one way or another by e-cigarettes. While this is an increase, the previous five years saw about 10 complaints filed per year. It is still a small amount when one considers the fact that 21 percent of all adult smokers have tried an e-cigarette.

The complaints range from burns to respiratory problems to nicotine poisoning.

Some of the problems reported include people inhaling secondhand e-cigarette vapor and becoming sick to the gizmo exploding in a smoker's mouth.

The FDA is also taking into consideration the recent spate of people reporting that they were sickened by their e-cigarette to the point where they felt it necessary to call their local poison control office.

Between these two problem sources the FDA believes it has to do something.

"Both together does suggest there are more instances going on," said David Ashley, director of the office of science at the FDA's tobacco division, adding that the FDA believes many more problems are going unreported.

E-cigarettes are battery-powered cigarette-shaped devices filled with liquid nicotine that is heated to create an inhalable mist. They were first brought here from China in 2007 and have gained popularity as a way to both quit smoking and allow people their nicotine fix while in places that ban smoking. These are not yet regulated by the FDA, but that is a situation that is about to change.

The government organization has sponsored some research into the impact e-cigarettes have on people. On one side there are the problems that have caused injuries, and then there is the idea that e-cigarettes act as a gateway product for young people to smoking real cigarettes.

"Some evidence suggests that e-cigarette use may facilitate smoking cessation, but definitive data are lacking," Dr. Priscilla Callahan-Lyon of the FDA's Center for Tobacco Products wrote in a recent medical journal article.

Proponents argue that the devices allow users to inhale the addictive nicotine without having to ingest the harmful tar products found in tobacco products.

There is no time frame on when the FDA plans to implement any type of regulation, but it has expressed its intention of doing so at some point.

Some in the e-cigarette market welcome some oversight.

Miguel Martin, president of Logic Technology, an e-cigarette maker, said "Clearly, because of the business opportunities, you have companies in an unregulated environment that are importing without checks and balances," he said, adding that while Logic pays attention to quality control, "some other companies just are not having the same diligence or focus."