Tests of another 11 freshwater fish samples, five from local sources and six imported, have found no trace of malachite green, the Health, Welfare & Food Bureau says.

Big head, grass carp, grey mullet, tilapia and mud carp were sampled.

The bureau has so far tested 96 samples of 14 types of freshwater fish - 49 local and 47 imported. Malachite green has been detected in 15 samples, all imported. A freshwater grouper was found to contain the highest level of the hazardous substance.

All imported samples of grey mullet, tilapia, milk fish, seabass, mud carp and yellow eel have tested negative for malachite green.