Customs officers are investigating after two brands of beauty masks were found to have excessive levels of potentially harmful bacteria - one exceeding the standard by 3,300 times.
This follows tests by the Consumer Council on 40 paper face masks which claim to have a whitening or moisturising effect, or both.
The council said the bacteria found in the DPC Hydro Whitening Mask and the Tiffanye Lavender Facial Mask could cause skin infections.
The DPC mask had 3.3 million units of bacteria per gram, 3,300 times the 1,000 units set by the China National Health Inspection hygiene standard for cosmetics.
The Tiffanye mask had 36,000 units, 36 times the standard.
Hong Kong does not have its own standard for such products.
The two samples were also found to have yeast and mould counts exceeding the mainland standard.