By Zheng Yi

A series of Chinese made shampoos endorsed in TV commercials by kung fu movie star Jackie Chan reportedly contain a cancer-causing chemical, according to a Hong Kong-based magazine.

The manufacturer, however, strongly denied the herb-infused products pose any danger to users.

Next Magazine said Wednesday that the Bawang Chinese Herbal Essence Shampoo Series, Bawang Hair Darkening Shampoo, and Royal Wind Shampoo produced by B&W International Group contained dioxane.

However, the magazine did not say how much chemical was found in the products during testing. In the ads, Chan said he initially turned down the chance to endorse the shampoo but changed his mind after washing his full head of hair with it. He also said he was pleased the shampoos use herbs instead of chemicals.

An unidentified employee at B&W told the Global Times that they use small quantities of dioxane in their shampoo products, and claimed it is not harmful to people.

Dioxane is irritating to the eyes and the respiratory tract, and is suspected of causing damage to the central nervous system, the liver and the kidneys.

The chemical is classified by the International Agency for Research on Cancer as a carcinogen, and is classified in California as a cause of cancer.

B&W issued a statement Wednesday, saying the magazine exaggerated the problem and accused it of inaccurate reporting.

The company said their products are manufactured in accordance with the laws of China, and have met the safety requirements of both Hong Kong and the mainland.

It added their products are in compliance with US and European Union standards.

The company warned that it reserves the right to take legal action against the magazine over the article.

"The concentration of dioxane in the products is far below the safety limit, and the products will not cause impact to human health," the statement said.

The company suspended trading in the Hong Kong Stock Exchange Wednesday. Its share price dropped by 14.116 percent to $5.05.

Jackie Chan, the recognizable spokesman for Bawang Chinese Herbal Essence Shampoo Series, did not comment on the report.

However, workers at his Hong Kong agency said they trusted the quality of the shampoos, ifeng.com reported Wednesday.