The Military Times PT365 blog reports that “once a curiosity at mall kiosks, e-cigs are popping up on tobacco shelves, in smoke shops and at military exchanges, which began carrying the battery-powered devices within the past two months. Since May, sales of e-cigs in the Army and Air Force exchanges alone topped 28,600.”

The piece continues: “But as e-cigs grow in popularity, government regulators and the military services are sorting out what rules should apply to these accessories, which turn a nicotine-infused liquid like propylene glycol or vegetable glycerine into an inhalable vapor.”