Fifty years ago, the U.S. surgeon general issued a landmark report warning Americans of the profound health risks from smoking cigarettes. Millions of Americans eventually quit; millions more tried to quit. Many wished they had been warned decades earlier.

Last week, the federal government moved to control a new, higher-tech smoking risk. The federal Food and Drug Administration proposed a sweeping set of rules to crack down on what officials called the “wild west” of electronic cigarettes.

E-cigarettes are battery-powered cylinders that heat up nicotine-infused liquids to create vapor. The e-cigarette smoker inhales — some of these devices even mimic a cigarette with a glowing light at the tip — and then puffs out a white mist.

The proposed FDA rules focus, rightly, on two areas:

• Children: The FDA proposes to ban the sale of e-smokes to anyone under age 18.

• Public awareness: E-cigarette manufacturers would be required to divulge the ingredients in their products. That will help researchers and potential smokers to better understand the risks that e-cigarettes pose to health.

The scientific debate is still simmering about the dangers of e-cigarettes. Unlike traditional cigarettes, e-smokes do not contain tobacco or some of the other harmful chemicals proven to cause cancer. So e-cigs may be less harmful than traditional cigarettes, and could help smokers trying to quit.

But there is mounting evidence that electronic cigarettes pose significant health risks. One recent, preliminary study concluded that the nicotine-laced vapor “promoted the development of cancer in certain types of human cells much in the same way that tobacco smoke does,” the New York Times reported.

Meanwhile, more young people are being drawn to the product. The National Youth Tobacco Survey found last year that 1 in 10 high schoolers had tried “vaping,” as it is known. That was double the number in the previous year. That number is likely rising, to the alarm of public-health experts who say the dangers of e-cigarettes are still far from established.

The FDA is taking a sound approach with its focus on curtailing e-cigarette sales to youngsters, warning adults about the dangers and promoting more research. It’s hard to say if e-cigarettes will always be a niche sales product, or will spawn a Mad Men-style generation of vapers.

If you’re tempted to vape, understand what we know and don’t know about the risks. Tough federal scrutiny now will help clear away confusion so millions of Americans one day won’t regret their choice.