Vizhinjam ‘seafood poisoning’: searching for marine algal toxins in fish becoming an onerous task, say officials

The investigations into the seafood poisoning incident at Vizhinjam is pointing to a dead end as searching for marine algal toxins in fish is like searching for a needle in a haystack because there is no easy way of identifying which fish/seafood might be contaminated.

Food Safety officials point out that the forensic report on the viscera samples of those who died of “seafood poisoning” alone can provide clarity on what caused the deaths, even though the angle of marine algal toxins – ciguatoxin or the deadly neurotoxin, tetrodotoxin – is being probed .

No stool or blood samples seem to have been collected from the deceased. Food safety authorities have also ruled out possible contamination through spoilage or unhygienic storage conditions

“We could not get samples of the fish that had been consumed by the people who fell sick. With fish roe emerging as the possible contaminated item that was commonly consumed by all those who fell ill, including the deceased, we are collecting samples of fish roe from Muttom in Tamil Nadu. Central Institute of Fisheries Technology (CIFT) has given us a list of big fishes (from which roe is usually collected), the samples of which are also being collected and sent to CIFT for toxicology studies,” an official said.

Food Safety officials are thus collecting samples of red snapper (chempalli), barracuda (cheelavu), trevally (vatta) and amberjack from major suppliers’ end for toxicology studies. They term this a wild goose chase, searching for the elusive marine algal toxin

“We are working within severe limitations because you need to invest a lot of money and time for regular surveillance of fish coming into the market to detect possible toxins. Our food labs are not equipped to test for toxins in food and we are not aware that there are any accredited labs in Kerala which can test for marine toxins in human samples. CIFT studies only fish samples and toxicology studies are time consuming,” an official explained.

A team of officials, including those from Food Safety department, CIFT, Fisheries department and Kerala University of Fisheries and Ocean Studies are drawing up an action plan on how surveillance studies on fish can be taken up on a regular basis.