US authorities slapped a temporary ban Wednesday on chemicals used to make so-called "fake marijuana" that has been used as a legal alternative to pot.
The Drug Enforcement Administration said it was using its emergency authority to temporarily control the five chemicals used for products with names such as "Spice," "K2," "Blaze," and "Red X Dawn," which are labeled as incense to mask their intended purpose.
"Over the past year, smokable herbal blends marketed as being 'legal' and providing a marijuana-like high, have become increasingly popular, particularly among teens and young adults," the DEA said in a statement.
"These products consist of plant material that has been coated with research chemicals that mimic THC, the active ingredient in marijuana, and are sold at a variety of retail outlets, in head shops and over the Internet."
The DEA said however that the products have not been approved for human consumption and there is no oversight of the manufacturing process.
The banned chemicals are JWH-018, JWH-073, JWH-200, CP-47,497, and cannabicyclohexanol, which are used to make "fake pot" products.
The DEA action makes possession or sale of the chemicals or the products that contain them illegal for at least one year while a review is conducted.
"The American public looks to the DEA to protect its children and communities from those who would exploit them for their own gain," said DEA acting administrator Michele Leonhart.
"Makers of these harmful products mislead their customers into thinking that 'fake pot' is a harmless alternative to illegal drugs, but that is not the case."
The substances are already banned in 15 US states and several European nations.
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