The regulators at America's Food and Drug Administration (FDA) could be forgiven for wanting a cigarette break. They rushed to meet a September 9th deadline to decide whether more than 6.5m e-cigarette products made by over 500 companies can remain on the market.
E-cigarettes have attracted keen government attention in recent years. More and more young people begin vaping (吸电子烟). In 2019 America's surgeon-general called vaping an epidemic (流行病) among you people, animadverting in particular products with "kid-friendly" flavours, such as oranges and grapes. Later that year more than 450 people in America suffered from a mysterious and severe lung illness that was linked to vaping.
Other countries, including Brazil, India and Singapore, have already banned e-cigarettes. So what goes into them, and how bad are they really?
The devices use an electric charge to vaporise (蒸发) a dose of nicotine (尼古丁) (accompanied, often, by various flavouring chemicals) . Nitrosamines, a family of chemicals causing cancers, have been found in e-cigarette vapour. Metallic particles from the device's heating element, such as nickel and cadmium, are also a concern. High exposure to these can increase the risk of cancer. It also contains harmful substances that can damage tissue or DNA, and which are thought to come mostly from flavourings.
Then there is nicotine. Besides being addictive, it is known to have a harmful effect all around the body. Scientists have done research on animals and humans, which suggests that exposure to nicotine at an early age could make users more influenced to other addictive substances later in life.