By Zhao Ran

As much as 80 percent of bee propolis products in the domestic market is tree gum that has been adulterated in order to save on production costs, the CCTV show Weekly Quality Report said on Sunday.

Experts said that while tree gum does not have undesirable health effects, it does not have the same health value as genuine bee resin.

Propolis is a resinous substance bees collect from tree buds. Bee propolis contains antioxidants called flavonoids, which are thought to possess qualities that boost the immune system, as well as help maintain healthy blood fat, blood pressure and blood sugar levels.

Statistics from the China Bee Products Association (CBPA) show that while the annual average output of bee propolis in the country is 300 tons, the actual sale of propolis is over 1,000 tons a year.

According to the report, the current price of an 80-gram bottle of bee propolis is 148 yuan ($ 22.53). However, nearly 90 percent of the product is made up of tree gum, which only cost 200 yuan ($30.44) per kilogram.

The report said the tree gum being passed off as bee propolis is a kind of adhesive resin extracted from the buds of poplar trees. The appearance of this tree gum is very similar to that of genuine bee resin.

Zhang Dexin, a specialist researcher of bee products at Beijing Defengtang Health and Technology Company, told the Global Times that this is a common practice used by many manufacturers to save on costs.

"Tree gum has no significantly bad effect on people's health. However, there are no curative effects for patients who take propolis with tree gum to reduce blood pressure or blood sugar levels. Some of the raw materials used by manufacturers are even worse than tree gum," Zhang said.

The fake propolis products not only contain tree gum, but also quercetin and rutin, extracted chemical powder that contains flavonoids, CCTV reported.

Jia Yaguang, deputy secretary-general of the Chinese Health Care Association, told the Global Times Monday that most bee propolis products are registered as healthcare products.

Some products have failed to obtain registration numbers from the State Food and Drug Administration because they do not meet the required standards.

However, these substandard products are still available on the market, and the authorities cannot supervise them because of the lack of a registration number, Jia said.