Medical experts are concerned about marijuana “dabbing,” a potentially dangerous way of using the drug. Dabbing appears to be increasingly popular among young people in New York City, according to The New York Times.

According to the Drug Enforcement Administration (DEA), dabbing is a method used to convert marijuana into a concentrate. It uses butane, which is highly flammable, to extract THC from the cannabis plant. THC is the psychoactive chemical in marijuana. This process has resulted in violent explosions, the DEA noted.

While marijuana in its traditional plant form has a THC concentration of about 20 percent, the wax used for dabbing can have a concentration of up to 80 percent, according to the DEA.

“In this process, shredded or ground up plant material is stuffed into a glass, metal, or plastic pipe, with a filter on one end and then the butane is forced in the open end of the pipe,” the DEA explains in a brochure. “As the butane goes through the pipe, the THC within the plant material is extracted and forced through the filter, usually into a receptacle. The receptacle is then heated to burn off the remaining butane, creating a butane gas.”

Dabbing is popular among teenagers, as well as workers on Wall Street, the article notes. Many people use vaporizers and vape pens, which are similar to e-cigarettes. They squeeze the extract into the chamber inside the pen and inhale.

The marijuana extract, also known as shatter, butter and honey, is on the radar of federal law enforcement officials. “We monitor any type of new twist on drug use in order to warn the public of its danger,” James J. Hunt, special agent in charge of the DEA’s New York division. “Not only is the method of production explosive, but the use has serious physical and psychological side effects.”