Electronic cigarettes are displayed for sale at Tasty Vapor in Oakland, Calif. (Ben Margot/AP)

The California Department of Public Health on Wednesday issued a warning about the dangers of e-cigarettes, as states across the country consider new regulations for the booming industry.

In a report issued Wednesday, the department urged legislators to regulate e-cigarettes like tobacco products. The growing popularity of the new devices presents a particular risk to children and teenagers, who increasingly report using them, the department said. Department of Public Health Director Ron Chapman told reporters Wednesday the department will begin a public education campaign warning of the dangers posed by e-cigarettes.

Chapman said he is particularly concerned about the variety of flavors in which the nicotine-containing liquid used in e-cigarettes is available.

“The availability of e-cigarettes in a variety of candy and fruit flavors such as cotton candy, gummy bear, chocolate mint and grape makes these products highly appealing to young children and teens,” Chapman wrote.

Electronic cigarettes, which vaporize liquid that contains nicotine, are different enough from regular cigarettes that existing laws do not regulate them. Dozens of states are considering new regulations, some backed by the e-cigarette industry itself and others pushed by health advocates.

The product also represents a major growth opportunity for tobacco companies, whose sales have slid as smoking rates of tobacco smoking have dropped. More than 200 e-cigarette companies operate in the United States, according to industry analysts, but five of them account for a little more than 80 percent of the market. Industry analysts at Wells Fargo estimated in 2013 that the e-cigarette market is likely to grow to $10 billion annually by 2017.

And while scientists have studied the health effects of regular cigarettes for decades, studies on the impacts of e-cigarettes are just beginning. The California report cited studies that show the vapor produced by e-cigarettes contains at least 10 chemicals known to cause cancer or birth defects. The report also cited preliminary studies that suggest e-cigarettes cause lung irritation and inflammation similar to that caused by tobacco cigarettes.

Industry advocates say e-cigarettes are much safer than traditional cigarettes, and they back restrictions on sales to minors. For regular smokers, the industry has positioned the product as a cessation tool, similar to  nicotine gum or patches. They also criticized the California report for omitting studies that reached different conclusions.

“It’s an overly alarming piece of propaganda that uses cherry-picked studies and turns what is a complex public health topic into a black-and-white issue,” said Greg Conley, president of the American Vaping Association. “What’s most disgraceful is that they are telling California smokers that if they’ve tried the gum and the lozenge and the patch and it hasn’t worked for them, they might as well keep smoking.”

Conley pointed to three clinical trials that measured the effectiveness of e-cigarettes in helping smokers give up traditional cigarettes, none of which was cited in the California report.

Health officials cited their own reports that show e-cigarette users are less likely to quit smoking. They are alarmed by the growing use of e-cigarettes by young adults and those under legal smoking age. More eighth-graders, 10th-graders and 12th-graders are using e-cigarettes than traditional cigarettes, according to state and federal surveys, and about 20 percent of e-cigarette users have never smoked traditional cigarettes.

California also has seen a marked rise in the number of reports to poison control centers of children having consumed e-cigarette vapor or liquid. The number of cases involving children 5 and younger tripled in just a year.

Officials pointed to television and radio advertisements promoting e-cigarettes, four decades after traditional cigarette advertisements were banned from the airwaves. In 2013, Kantar Media Intelligence estimated the e-cigarette industry spent more than $80 million promoting its products.

The federal Food and Drug Administration has proposed adding warning labels and ingredient lists to e-cigarette packaging, although new rules could be years away.

Health departments in Arkansas, Oklahoma and Tennessee have issued warnings similar to California’s, and more than half of all U.S. states have passed some level of regulation of e-cigarettes.