Deerfield Beach, Florida (CNN) Emergency rooms in South Florida are filling up with patients suffering from synthetic drug overdoses, and the problem is getting worse due to a device that's ostensibly supposed to help people quit smoking.

Vaporizer pens are becoming the new way for drug users to not only get high, but do it discreetly -- at times right under the noses of police, parents and teachers.

And it is no local phenomenon. From big cities like St. Louis to small villages in upstate New York, these vape pens are popping up more frequently in drug busts, and the steady rise of abuse is alarming communities across the country.

E-cigarettes, or vape pens, have been around for more than a decade but have boomed in popularity recently because of marketing to nicotine users looking for a safer alternative to smoking cigarettes. Also fueling the trend is the accessibility of oil concentrates. A vape pen creates an inhalable vapor with a small inner coil that slowly heats, creating a vapor that is inhaled.

Water-soluble synthetics are easily converted into liquid concentrate that can go into the device cartridges and be vaped just like nicotine and other legal substances. It makes it nearly impossible to tell what is inside someone's vape. It could be nicotine, marijuana concentrate, or fruit-flavored, nicotine-free "e-liquid," popular among kids. Or worst of all, it could be a deadly concoction of chemicals, often a product of China, known as synthetic drugs.

"It's the concealment method; we don't know what is in a vape pen until we actually have it tested by a forensic laboratory," said Supervisory Special Agent John Scherbenske of the U.S. Drug Enforcement Administration.

Vaping in the ER

Just a few weeks ago in Deerfield Beach, Florida, Lt. Ozzy Tianga of the Broward Sheriff's Office arrested a man high getting on "flakka" with a vaporizer pen. Flakka is a deadly and cheap synthetic drug also known as "$5 insanity," and it's causing huge problems for law enforcement.

Days later, a man who'd been high on flakka was discharged from Fort Lauderdale's Holy Cross Hospital, only to go into the bathroom, vape more drugs and overdose again, said Dr. John Cunha, an emergency room physician there.

"I have had patients in my practice in the emergency room that I have walked in on that are actually vaping at the bedside," Cunha said. "...Someone could be sitting in their room in the emergency room and they could be vaping in between being seen by medical professionals, and we would have no idea what they are taking."

The scariest part is the rate at which it's trending.

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Spending an afternoon in Deerfield Beach with Tianga, driving down a few miles of the main drag, Federal Highway, we passed at least a half-dozen vape shops and most of them still had temporary signs -- an indication they were brand new.

"Every time I drive, I see another store," Tianga said.

There are currently no federal minimum age or youth restrictions for e-cigarettes, according to the DEA, although most states and cities have passed laws banning the sale to minors.

One small town in upstate New York, Victor, even put a six-month moratorium on any new vaporizer stores after community outcry over the difference in federal laws regulating vape pens in comparison to cigarettes.

But the discretion of the device is the most common complaint among law enforcement, city officials, parents, teachers, and medical personnel.

Tianga said he often encounters people with vape pens, and he's left to wonder what's inside them, or what the user might be high on.

"These individuals can smoke it right in front of you. And many of times these vapes have no scent, or because they are a chemical substance the scent can be changed. It could be a fruit smell. It could be no smell at all," Tianga said. "An e-cigarette is not your traditional drug paraphernalia. So it's much more difficult for a law enforcement officer to establish probable cause to determine this is actually a device intended for the consumption of narcotics."

Hard to know who's vaping drugs

It only takes a quick search to find examples on social media of students bragging about getting high in class, in their bedrooms, discreetly with the help of vapes.

"Look on Instagram," said Barbara Carreno, spokeswoman for the DEA national headquarters in Washington. "You'll see many thousands of posts by young people, snickering about smoking it in class."

Gone are the days of getting caught smoking pot in school because you smelled like a skunk.

Among the most popular vaped synthetics, Scherbenske said, are the so-called "legal weeds" -- K2 and Spice, synthetic drugs that mimic other drugs in many ways, but can have severe side-effects, too.

"They sit in the back of the room, and they think it's funny," Tianga said. "They are vaping, and what they are vaping -- again -- I cannot determine. From the smell I cannot determine. I actually have to get the pen out of their hand and there is very few field test kits that will tell you exactly what they are vaping."

Tianga now travels around Broward County educating teachers, parents, residents, doctors and emergency response personnel about the dangers.

At a Deerfield Beach community forum, Tianga gave a chilling presentation that got audible reactions. Thirty-three people have died so far this year in Broward County from synthetic drug overdoses, with two more suspected deaths under investigation.

The mayor of Victor, the upstate New York town that temporarily banned them, said many of the concerns were about the number of teens using the devices.

"It's kind of like the Wild West of vaporing," Mayor Jason Ashton said. "There was no zoning or code laws in place to prevent or to say where that kind of store could go," "When the outcry started and I was getting phone calls daily, one idea floated out was the put a hold on it. Find out what we can and can't do. What this product really is. Does the outcry really demand this attention? It gives us time to mitigate the problem and do research. We've found that science hasn't kept up with the trend."

'The future of pot'

It's a frightening combination -- both synthetics and vaporizers' gaining popularity -- each presenting new challenges to law enforcement used to dealing with the set rules of traditional drugs.

Rising usage of synthetics are being blamed for major spikes in murders in Washington, D.C.

But vape shop owners, several who tell us they never sell to anyone under 18, say the devices are helping people, not hurting them.

Carly Cromer, who manages Save on Vape in Deerfield Beach, said the goal isn't to attract people to start using nicotine.

"As an industry, it's to get people to quit smoking," Cromer said, noting that it's unfair to label the industry based on people who are abusing a product.

In Denver, where marijuana is legal, vape pen manufacturers say the ability to regulate intake with a concentrate inside a vape pen is essential for users who want to have more control over what they smoke.

Steve Berg, chief financial officer of O.Pen Vape, calls it "the future of pot."

The trend is too new for there to be data to crunch, to back up what police officers and emergency room doctors are seeing.

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Jim Hall, a drug abuse epidemiologist at Nova Southeastern University, said there are methods of tracking almost every other type of ingestion, from smoking to shooting, to oral consumption.

"But not vaping," he said.

That's going to start changing, because it's trending upward, Hall said.

"We know that synthetics are being vaped. We know that kids are using synthetics," he said.

Some findings from studies touching on the subject are disturbing.

The Centers for Disease Control and Prevention said in April that e-cigarette usage among middle- and high-schoolers tripled between 2013 and 2014. Usage among high-schoolers was 13.4% last year.

Most telling, Hall said, is that some kids had never smoked before. They are new users.

Cunha predicts that by the time the research catches up, the problem will be too big to control.

"I think that these devices do have a role in helping people get off of actual cigarettes and that they may be proven safer in that case, but in the hands of teenagers and drug abusers, they are definitely a very dangerous thing to have," he said.