Showbiz celebrities are known to have a knack for selling merchandise. But if Chinese regulators have their way, stars may have to be consumers of the products they endorse before they can make millions by hawking them on video screens and billboards.

In a draft revision of the law that governs advertising practices, submitted to the National People's Congress this week, a new clause was added that dictates the behavior and responsibilities of whoever recommends a product or service to the public.

It has been widely interpreted as an effort to curb celebrity endorsements that go against common sense.

If the law is changed, Taiwan singer and actor Jiro Wang might lose his two-year, NT$10 million ($335,000) deal representing a brand of sanitary pads. He claims his qualifications for endorsing this brand include buying the product for his girlfriend and not feeling embarrassed about it.

Other male stars such as Show Lo, Bolin Chen and Yoga Lin also endorsed this feminine hygiene product but may not be able to do so if they want these ads to reach a vast audience. (Taiwan and Hong Kong stars are paid astronomical amounts for such gigs mainly because of their fan bases on the mainland.)

Veteran star Liu Xiaoqing often appears in commercials that tout the virtues of plastic surgery, but in interviews she categorically denies that, despite widespread suspicion, she has ever undergone such treatments herself.

US actress Cybill Shepherd showed a similar self-contradiction in 1987 when she promoted the American Beef Industry Council but in interviews admitted she was a vegetarian. She ended up being removed from the campaign.

Sometimes, there is a palpable condescension and hypocrisy on the part of celebrities who appear in advertisements. They seem to imply that "I'd rather be caught dead than be seen using this product."

But advertisers, who still pay big money to associate their products or services with known quantities in the entertainment industry, may be caught off guard and lose a bundle when these expensive "representatives" get into trouble.

When teen idol Kai Ko was busted for drugs by the Beijing police, the dozen or so companies that had hired him to hawk their wares suddenly found themselves in a dilemma. Some quickly removed him from their advertising campaigns, while a few, smaller domestic businesses said they would "go through this difficult time with him".

Unlike Hollywood stars who limit their commercial exposure for fear of diluting their public image, Chinese celebrities get most of their income from endorsement deals, and the popularity of these stars is often measured by the deals they make and the sum total of earnings they get from them.

raymondzhou@chinadaily.com.cn