They are gaining in popularity but are e-cigarettes safe? After spotting a young woman ‘vaping’ on the Toronto subway line a few weeks ago, I decided to take a look at the topic.

An electronic or e-cigarette is a cylinder-shaped canister made of plastic or stainless steel that looks like a regular cigarette. A little battery system heats and vaporizes a liquid, ‘smoke juice,’ which may contain nicotine, propylene glycol, polyethylene glycol or other chemicals. An indicator light glows during inhalation, similar to a regular cigarette. E-cigarettes are sold in various flavours, like menthol and cherry, liquor flavours like piña colada and peach schnapps, and candy flavours like chocolate, gummy bear and bubble gum. This ‘vapor bar’ in New York offers more than 80 flavours.

In Canada, e-cigarettes containing nicotine are not approved for sale, yet they can be purchased over the Internet. “Nicotine is a drug, and e-cigarettes containing nicotine are drug-delivery devices. Health Canada has always treated them as such, which makes Canada’s laws governing these devices among the most restrictive in the world,” says Matthew B. Stanbrook, MD, PhD, in a recent editorial in the Canadian Medical Association Journal.

South of the border in the United States it’s an entirely different story as e-cigarettes are currently sold there without any regulatory oversight. Manufacturers are spending heavily on celebrity endorsements, TV ads, NASCAR sponsorships, and product giveaways including starter packs in swag bags at the Oscars and starting this month, 1 million free products at nightclubs. The $1.5-$1.7 billion market tripled in size last year, but that growth may change soon because the FDA is expected to clamp down with new regulations as early as the end of October.

So are e-cigarettes safe?

E-cigarettes do not contain the tar and combustion ingredients that regular cigarettes have, but that doesn’t necessarily make them safe. Without regulation, nobody knows what chemicals they are actually inhaling, if those chemicals are safe or if labelling is accurate. Propylene glycol, for example, is a known irritant. The American Lung Association says, “In initial lab tests conducted by the FDA in 2009, detectable levels of toxic cancer-causing chemicals were found, including an ingredient used in anti-freeze, in two leading brands of e-cigarettes and 18 various cartridges.” The FDA also found that the nicotine delivered by one brand was highly variable from cartridge to cartridge.

Are e-cigarettes a good alternative for smokers who want to quit?

Maybe, but ‘safer’ and ‘safe’ are two entirely different things. And so far, the evidence for smoking cessation success is slim. One study in New Zealand, reported in The Lancet, showed that e-cigarettes were modestly effective for helping people quit compared to nicotine patches, with a success rate of 7.3% for e-cigarettes versus 5.8% for nicotine patches as measured at a six-month endpoint. Not exactly a panacea.

Nicotine is an addictive substance, no question there. Experts on both sides of the border are warning that this new nicotine delivery system could hook a new generation. The CDC is alarmed about the marketing efforts targeting youth as the percentage of adolescents using e-cigarettes doubled to 10% in 2012 compared to 4.7% the year before. “About 90 percent of all smokers begin smoking as teenagers,” said Tim McAfee, M.D., M.P.H., director of the CDC Office on Smoking and Health, “We must keep our youth from experimenting or using any tobacco product. These dramatic increases suggest that developing strategies to prevent marketing, sales, and use of e-cigarettes among youth is critical.”

The National Association of Attorneys General added significant heft to the need for regulation in a letter to the FDA, signed by more than 40 officials. Local governments like the state of New York and cities and towns north of Boston however, are tired of waiting for federal regulations and are looking at putting their own bans into place.

It will be interesting to see how the FDA rules on this in a few weeks. At a bare minimum, way more research needs to happen to answer key questions about product safety and whether e-cigarettes are good long-term alternatives for people who want to quit smoking.