Just as cigarette smoking drops to its lowest level in years, e-cigarette use, a.k.a. "vaping," is exploding among middle and high school students. Teens may blow off the trend as harmless, but experts think otherwise.

"It's important to understand that this is a drug delivery system. In some ways, calling it 'vaping' almost makes it sound benign and not dangerous," says Dr. Stephen Thornton, a medical toxicologist and emergency room physician.

What are e-cigarettes? Initially marketed as smoking cessation devices, e-cigarettes are electronic nicotine delivery systems that use lithium-ion battery operated devices to heat up and vaporize a flavored, liquid solution called e-juice. The user then inhales the vaporized solution. 

What's in the e-juice? The e-juice usually contains nicotine extract, which is mixed with propylene glycol (typically used in inhalers) and flavorings, like mint, fruit loops, gummy bears and passion fruit.

Since solutions aren't currently regulated by the FDA, buyers have no way of knowing how much nicotine is in a product, including those that claim to contain zero nicotine.

"Right now many manufacturers are putting whatever they want in it, including potentially harmful chemicals," says Jamie Katz, a youth drug and alcohol prevention coordinator.

What are the risks? Chemicals found in e-cigarette vapor include aldehydes (formaldehyde, acetaldehyde, acrolein and acetone); diacetyl, a highly toxic chemical linked to lung disease; volatile organic compounds found in car exhaust; and heavy metals like nickel, lead and chromium. 

"Unfortunately, we still need more time to know exactly what kind of short or long-term problems you're going to get from exposure to these chemicals," Thornton says. "Some products are probably safe if you eat or drink them, but once you start inhaling them into the lungs and you start vaporizing them, it changes the dynamics."

In the short-term, users may be more prone to viral infections in the lungs and asthmatic types of reactions. Hospitals are also treating more people with traumatic injuries related to the devices exploding in their faces or in their pockets.

"I don't think people appreciate how much power is in the devices in order to get the heat that vaporizes the solution," Thornton says. "If you think about it, you're holding up a grenade to your face and if it goes off, that's going to be a very bad story." 

What's the appeal? According to Katz, kids think vaping is cool, healthier than smoking cigarettes, and a stress reliever.

Leaving no odors other than a light, fruity scent, e-cigarettes are easy to conceal in a pocket or purse. They often resemble pens or USB flash drives, like JUUL, which is especially popular among kids.

Then, there's the celebrity effect. "An adolescent sees celebrities like Leonardo DiCaprio and Katherine Heigl using these products openly in public, and there's that diminished sense that it's not a harmful product," says Kevin Kufeldt, an adolescent treatment center program manager.

Vape "cloud chasing" competitions featured online, in which people blow clouds and do tricks with e-cigarettes add to the attraction.

Creating a new generation of addicts? With candy flavored solutions and labels like Unicorn Milk, Cotton Candy and Zombie Juice, many experts believe that e-cig marketers are specifically targeting kids. 

"I doubt there's a 45-year-old guy out there who says 'Man, I really need to have my spearmint bubble gum vape today,'" Thornton says.

A JUUL pod contains 59 milligrams of nicotine per milliliter of liquid, which the manufacturer says is equivalent to the amount of nicotine in a pack of cigarettes.

"On a milligram per milligram basis, nicotine is ten times more potent than heroin," Kufeldt says."Kids will tell me they think they actually smoke more with e-cigarettes than with a traditional cigarette because they can use more often throughout the day."

Research suggests that teens who vape are more likely to smoke cigarettes later. Many users also vape substances like synthetic cannabinoids, fentanyl, Xanax and marijuana.

Talk to your kids. Promote a healthy lifestyle, discuss the harmful effects of addictive substances on the body, and talk about healthier ways to manage stress.

"Parents can influence their kids' decision to vape," Katz says. "Talk to your children about your expectations and why you don't want them to use e-cigarettes. You can expect them to live tobacco free."

Take this quiz to see how much you know about this controversial topic...

Globally, which two drugs claim the most lives?

A. Heroin

B. Opium

C. Alcohol

D. Nicotine

Answers: C and D

What is the average age kids first try addictive substances?

A. 16

B. 13

C. 8

D. 12

Answer: D

The legal age to purchase e-cigs ranges between 18 and 21, depending on your state or municipality. How are kids obtaining the products?

A. Friends

B.  Online

C. Parents

D. All of the above

Answer: D

Sources: Dr. Stephen Thornton; Kevin Kufeldt

POISON ALERT!

Many youngsters find and ingest the e-juices, mistaking them for candy or actual juice. Liquid nicotine is extremely poisonous. Symptoms include nausea, vomiting, tremors and rapid heart beat. In severe cases, seizures and death can occur.

Sources: Dr. Stephen Thornton; American Association of Poison Control Centers

Christa Melnyk Hines is a nationally published freelance journalist and author. She and her husband are the parents of two middle school-aged sons. Her latest book is Happy, Healthy & Hyperconnected: Raise a Thoughtful Communicator in a Digital World.