Samples of caterpillar fungus from markets of poor quality, tests show

PUBLISHED : Friday, 31 July, 2009, 12:00am
UPDATED : Friday, 31 July, 2009, 12:00am

Some of the Chinese caterpillar fungus sold in local markets for use as a medicinal herb does not deserve its high price, a university study finds.

Chinese University tested 15 samples of caterpillar fungus and 10 capsule products collected from shops in Sheung Wan, Kowloon and the New Territories last month.

Among the fungus samples, five were found to contain another type of fungus that looked similar to the real thing but might cause dizziness and vomiting.

One sample was found to have been soaked in potassium alum to make it heavier, meaning it could be sold for a higher price, but the industrial chemical was also likely to cause vomiting, the study said.

In traditional Chinese medicine, the caterpillar fungus is deemed effective in curing persistent coughs and improving human immunity. It grows in alpine grass areas as the fungus invades a caterpillar, kills it and grows. The current price in Hong Kong is between HK$60 and HK$100 per gram.

Pieces of iron were found in some samples, apparently used to prevent the fungus from breaking during transport.

Packaged or cheap samples were of especially poor quality, said department of biology professor Paul But Pui-hay, who initiated the study.

'We found all three packaged samples we took had some fake materials added in them,' he said. 'And those priced under HK$60 per gram often had more problems as well.'

Professor But called for consumers not to buy packaged or cheap samples of caterpillar fungus.

Similar quality problems were also found in the capsule versions. Two products that claimed to be made from the caterpillar fungus were actually made from a much cheaper medical herb.

Most of the products labelled as caterpillar fungus failed to clearly state the substances and composition of the capsules, misleading shoppers, Professor But said.

The study did not reveal the brands or information regarding the retailers.

'We believe that intermediary businessmen should take the major responsibility for the malpractice, and we have reflected the problems to the relevant government departments,' he said.