"There is so much we don't know about the health impacts of these products."

E-cigarettes have been officially banned in San Francisco, the first city in the US to do so. City officials voted unanimously on Tuesday to outlaw e-cigarettes, citing health reasons, noting that no available product has undergone premarket review by the US Food and Drug Administration to date. Stores in the city will no longer be permitted to sell vaporisers, while it will also now be illegal for online retailers to deliver related products to addresses in San Francisco. The move has been criticised by Juul Labs, which is based in the city and is recognised as the most popular provider of e-cigarettes in America. In response, a Juul Labs spokesperson argued that the ban will create "a thriving black market" in the area.

"This full prohibition will drive former adult smokers who successfully switched to vapour products back to deadly cigarettes, deny the opportunity to switch for current adult smokers, and create a thriving black market instead of addressing the actual causes of underage access and use," said Juul's Ted Kwong.

CNN reports that the measure has been approved by Mayor of San Francisco London Breed, with the policy set to come into effect six months after it becomes an effective policy. "There is so much we don't know about the health impacts of these products, but we do know that e-cigarette companies are targeting our kids in their advertising and getting them hooked on addictive nicotine products," said Breed. "We need to take action to protect the health of San Francisco's youth and prevent the next generation of San Franciscans from becoming addicted to these products."