PARIS -- As the number of countries to pass anti-smoking laws in Europe increases, so do sales of electronic cigarettes. And on Jan. 2 Spain joined the wave of countries to ban smoking in enclosed public space, opening another market for e-cigarette manufacturers, according to AFP.

"We have seen sales grow by 30 percent each year since 2007 when we launched our product," said a spokesman for EdSylver, one of the leading makers of the product invented in China in 2004.

While electronic cigarette manufacturers contend that their product, which simulates the sensation of a cigarette and can contain nicotine, is not harmful to smokers or others around them, some health experts reject that claim. At a World Health Organization conference in Uruguay in November, one of its leading anti-tobacco experts Eduardo Bianco said electronic cigarettes "sabotaged smoking prevention efforts," which were designed to encourage people to quit, AFP reported.

The French national office for smoking prevention said the purpose of the e-cigarette was "ambiguous" and condemned its sale in pharmacies. The French National Committee Against Tobacco has also come out against the product. "This product offers no medical support for quitting smoking, there are some countries that have banned it. For the moment, this product has not been evaluated in a scientific way," added Professor Yves Martinet, head of the French National Committee Against Tobacco.

For their part, tobacco retailers deny that sales of the device are increasing, according to AFP. "It doesn’t sell at all; some of our members still have stocks from last year," said Gerard Bohelay, head of an association of tobacco retailers in Paris.