A mullet and a fishcake in Hong Kong had been found to contain malachite green in the Center for Food Safety's Southeast Asian food safety survey, the Center said on Tuesday.

Three hundred food samples, including snacks, soups, main dishes, rice, pasta and noodles, desserts, sauces and spices, and drinks, were collected from more than 100 retail outlets. All passed microbiological tests, it said.

But a sample of Thai steamed mullet and a deep-fried fishcake contained malachite green at levels of 0.87 ppm and 0.012 ppm. The Center noted the levels were unlikely to pose adverse health effects upon normal consumption.

The center had asked the vendors to stop selling and dispose of the affected food. It had traced the source and issued warning letters to the operators concerned.