Consumer watchdog found contaminants in all prepackaged edible fungi it tested

Hong Kong’s consumer watchdog said after testing 28 samples of prepackaged edible fungi sold on the market, 12 samples were found to contain at least 1 type of pesticide, while all contained metallic contaminants though unlikely to cause any significant health risk.

From August to September 2022, the Consumer Council sourced 10 samples of black fungus, 9 of white back black fungus, and 9 snow fungus from major retail outlets, with prices ranging from HK$12 to HK$99 per pack, equivalent to a unit price of HK$7.9 to HK$130.3 per 100g.

The council said on Thursday that although pesticides and metallic contaminants were found in the samples, the amount detected was small, and as consumers tend to consume a limited serving size of edible fungi each time, in which the overall risk is not significant.

The test found 2 black fungus samples and 2 white back black fungus samples, each contained 1 pesticide residue, but by using a conversion factor to extrapolate residues in their fresh state, estimates were below the limits for fresh edible fungi under the Hong Kong Pesticide Residues in Food Regulation (Pesticide Regulation).

Meanwhile, among the snow fungus samples, 1 to 5 types of pesticide residues were detected in 8 samples. One sample labeled “organic” was found with residues of 4 types of pesticides, of which the level of Abamectin B1a would reach the maximum residue limit of the Pesticide Regulation.

“However, for a 60kg adult, assuming no other dietary exposure to the pesticide in question, would need to consume 207g of the sample - about 21 bowls cooked - per day to pose a health risk,” the council noted.

The council urges the industry to conduct regular product tests to ensure pesticide residues in their products comply with the relevant regulations.

Separately, the watchdog reminded members of the public to avoid soaking the fungi for too long in view of the possible risk of Bongkrekic Acid Poisoning.

It said consumers should note that soaking at room temperature should not be too long, usually no more than 2 hours; otherwise, it should take place in a refrigerator.

“This is because soaked snow fungus, black fungus, and white back black fungus are more susceptible to contamination by the bacterium Burkholderia cocovenenans, which may produce toxic bongkrekic acid.

“This toxin, once produced, cannot be destroyed by washing or cooking and may cause abdominal pain and vomiting, or in severe cases, cause deranged liver function and even death,” it added.