BERLIN, Sept. 20 (Xinhua) -- The International tobacco fair InterTabac started in the city of Dortmund on Friday. This year's highlights were e-cigarettes and shishas, covering several halls of the approximately 40,000-square-meter exhibition space in Dortmund's Westfalenhalle.

"As a trendy type of relaxation, the water pipe is becoming increasingly popular", Sabine Loos, CEO of the fair's host commented on Friday.

The trend towards e-cigarettes was intensifying, the German association of the e-cigarette trade announced at InterTabac on Friday.

According to the association, electric vaporizer and accessories generated revenues of between 600 and 650 million euros in Germany in 2019, increasing by up to 25 percent compared to last year.

However, the German Cancer Research Center (DKFZ) warned that although e-cigarettes were "very probably much less harmful" than tobacco cigarettes, they were "not harmless lifestyle products".

"Non-smokers should not use e-cigarettes because of the unknown long-term effect on health", the DKFZ wrote at the end of 2018.

According to the German cigarette association (DZV), smokers in Germany spent more money on cigarettes than last year.

In the first half of 2019, cigarette sales in Germany amounted to around 11.4 billion euros (12.57 billion U.S. dollars), five percent more than in the same period last year although this increase was partly caused by higher prices.

As a reaction to tests by the DKFZ, several states in Germany, such as North Rhine-Westphalia, Hamburg and Lower Saxony are demanding a ban on smoking in cars if minors or pregnant women are onboard.

It should be "natural not to smoke" in the presence of minors or pregnant women, said Klaus Reinhardt, president of the German Medical Association (GMA). "Where this insight is lacking, the state must intervene."

In Germany, around 120,000 people die because of smoking every year, according to German Cancer Aid.

The number of young smokers in Germany has decreased significantly over the last years because of advertising bans, higher taxes on tobacco products and the raising of the legal age limit from 16 to 18 years.

However, German Cancer Aid is estimating that around 24 percent of adults and seven percent of children and adolescents in Germany smoke.