And when business owners call the county to ask about legality, health officials already recommend forbidding the practice.

LONG-TERM STUDIES SCARCE

No long-term studies have been done on the burgeoning device. And the results so far on human health are muddled by a lack of comprehensive research and by industry-funded studies.

That’s not to say there aren’t reasons to be concerned. People with asthma, heart disease and respiratory disease have already been warned off. The World Health Organization and the U.S. Centers for Disease Control are both advocating for more research to be done.

“There have been some studies done on the products and 10 known agents have been found that are known to cause cancer or reproductive toxicity,” Oxtoby said. “We think that is too big of a health risk to expose the population to.”

Meanwhile, 48 state attorneys general, including Arizona’s, have asked the Food and Drug Administration to get involved. The agency has yet to look at electronic cigarettes.