Adulteration
It is suspected that the large loads of fish seized were laced with formalin, a carcinogenic substance, in a bid to extend their shelf life.
Image Courtesy. Peter Grabowski /Wiki Commons

On June 24, fish lovers in Kerala were in for some worrying news. 6,000 kg of fish was seized at the state border checkpost at Walayar in Palakkad. The seized fish, mainly prawn and shrimp being brought in from Andhra Pradesh, were found to be laced with formalin, a carcinogenic substance.

This was done as part of Operation Sagar Rani led by the Joint Food Safety Commissioner (Administration), Food Safety Intelligence officials from Kozhikode and Ernakulam, and the district Food Safety Squad in Palakkad.

To add to this, 9,500 kg of prawn was seized on Monday night from Thoothukudi and Kanyakumari. The shipment, on its way to Kollam in Kerala, is also believed to be laced with formalin.

But what is this substance and why is it causing so much panic among fish eaters?

What is formalin?

Formalin is derived from formaldehyde, which is a substance that is carcinogenic to humans. Mixed in the right proportion with water, the paste is used for embalming and preventing the decay of dead cells. Formalin ,which contains 37–40% formaldehyde, is used in mortuaries and labs.

Formalin is often used to preserve fish, which is an easily perishable food whose value depends on its freshness. And when fish is imported from another state, to prevent rot during transport, fish traders resort to using formalin, even though formalin consumption is harmful to human beings.

How does formalin affect humans?

There are several risks associated with ingesting formalin – having even 30 ml of a solution, which contains as little as 37% formalin, can kill a fully grown adult. Once ingested, formalin releases toxins into the body, and the sustained ingestion of formalin can eventually lead to cancer.

Breathing even the smallest amount of formaldehyde gas can lead to pneumonia and bronchitis.

If formaldehyde is present in the air at a level more than 0.1 ppm, people could experience a burning sensation in their eyes, nose and throat, apart from coughing and sneezing. They could also experience nausea and skin irritation.

If formalin reaches the stomach, a person could experience stomach ache and nausea. Even if the fish or vegetables treated with formalin are cooked, it doesn’t stop the formalin from releasing the toxins into the body.

How do you detect it?

Union Agriculture Minister Radha Mohan Singh launched a kit devised by the Central Institute of Fisheries Technology (CIFT) to help detect if fresh fish has been treated with formalin. The kit contains strips of paper and a reagent solution. If anyone suspected their fish is adulterated, they should first rub the fish with the paper and then put a drop of the solution on the paper. If it turns dark blue, it means the fish is contaminated.

Other ways of detecting if the fish has been contaminated includes checking if the fish has rubbery flesh, red gills or hard scales. Of course, none of these methods are fool-proof and the only way to know for certain if a fish has been contaminated is to send it to a lab for testing.

What will the Kerala government do now?

State Health Minister KK Shailaja addressed a press conference in Thiruvananthapuram and assured that the government would take strict action against those contaminating fish with formalin. The Health Minister said, “Operation Sagar Rani mission was started last year as there were suspicion that poisonous fish was being transported to Kerala from other states. This is a complicated issue and does not pertain only to the Health Department. Hence, action can’t be taken in a hurry.”

For now, the fish seized have been sent to labs in the state to detect the presence of formalin. The labs have been asked to deliver the results as soon as possible.