The public are advised not to consume cockles from Sungai Geting near here for fear that the shellfish may be contaminated by an algae phenomenon known as the 'red tide.'

The sale of the cockles from the area is also prohibited until the toxin level of the water has been assessed by the state Fisheries Department.

State Health Department director Datuk Ahmad Razin Ahmad Mahir said the high level of toxins in the red algae is poisonous and could be fatal.

"The prohibition period depends on the next round of checks by the Fisheries Department.

"The allowed level is at 80 micrograms/100 grams tissue. However, the level now is at 3,000 micrograms which is very dangerous," said Razin after a visit to Sungai Geting on Sunday.

According to him, warning notices have already been circulated to all outlets selling seafood.

He added that cockles from other rivers are safe to be consumed.

Meanwhile, Universiti Malaya senior research fellow, Prof Dr Leaw Chui Pin said those who suffered from the red algae toxin will show symptoms such as shortness of breath, numbness and muscle paralysis.

In fact, in certain cases, it could even be fatal.

Red algae has been detected in Sungai Geting since 2001.

At that time, six individuals suffered food poisoning with one of them met his untimely demise due to consuming shellfish from the river.

The growth of red algae is a natural phenomenon and a large presence of such algae will cause the river water to appear red.

In a related development, State Fisheries Department director Mohd Zain Saad revealed that the presence of red algae had not affected the income of local fishermen.

According to him, the fishermen could still collect shellfish from other rivers as the red algae was only found in Sungai Geting.

The prohibition order from selling shellfish from Geting River was enforced since September 10.

So far, no case of food poisoning has been reported.