As cigarettes lose favor, tobacco companies pin their hopes on the fast-growing e-cigarette market,

Over the past decade, as health agencies promoted it as a smoking cessation aid and cigarettes continued to lose favor, the e-cigarette industry has grown rapidly.

However, the e-cigarette industry is facing a reckoning. Governments are seeking to restrict the sale of disposable e-cigarettes due to growing concerns about addiction among young people and non-smokers.

The CEO of the UK e-cigarette company Totally Wicked, and chairman of the Independent British E-Cigarette Trade Association, Marcus Saxon, stated: "The e-cigarette market is valued between $3 billion and $4 billion. You can estimate that intelligence also indicates that the illegal market could be as high as two-thirds of that amount."

As cigarette revenues decline, large tobacco companies are hoping to profit from the rapidly growing e-cigarette market. Owen Bennett, a global tobacco and cannabis equity researcher at Jefferies, told CNBC: "The traditional cigarette model is facing increasing pressure from declining sales."

As of October, 28 countries have banned the sale of e-cigarettes. Countries such as the UK, Germany, France, Ireland, and Belgium are exploring how to ban the sale of disposable or single-use e-cigarettes as they continue to gain popularity in the market.

However, implementing such regulations may be a tough battle.

Jasmin Kooja, a senior research associate at the Tobacco and Alcohol Research Group at the University of Bristol, stated: "What we are seeing in the US is that e-cigarettes have begun to stabilize, and I think they are starting to decline slightly. So I think we may not see greater growth."

"I think we have reached the peak popularity of e-cigarettes, but how long it will take for their popularity to decline remains to be seen."