There’s good news for the city’s fish lovers. After a nationwide scare of fish laced with formalin, a cancer-causing chemical preservative, 27 samples collected from fish markets across the city by The Hindu have tested negative for the chemical.
Formalin is formaldehyde in water and is routinely used in mortuaries to preserve bodies. Fish traders have found this chemical to extend the storage life of the catch and to give it an appearance of freshness.
Over the last few weeks, there has been an uproar after many States found rampant use of the chemical in fish meant for consumption, putting consumers at risk. The Goa government had even banned fish imports from other States as a precaution.
Test drive
To get to the bottom of the quality concerns, The Hindu collected 27 samples of saltwater and freshwater fish from three retail markets — Four Bungalows in Andheri (West), Saki Naka in Andheri (East) and Godrej Nature’s Basket, Bandra — and two wholesale points: Sassoon Dock and Dadar fish market.
To buy or not to buy: Fish from Andhra Pradesh are on display at a market in the city on Sunday.
The samples were of the most commonly consumed fish: bombil, mandeli, halwa, pomfret, rohu, papda, katla, hilsa, tangra and rawas. The samples were collected from the five points on July 19 and 20, and were sent for testing at the Central Institute of Fisheries Education (CIFE) in Versova. The reports, which The Hindu received on Saturday, revealed that all samples had tested negative for formalin.
“This shows that the catch coming to Mumbai is not contaminated by the chemical,” Dr. Gopal Krishna, director and vice-chancellor of CIFE, said. The institute falls under the Indian Council of Agricultural Research. Dr. Krishna said the tests were carried out using a CIFT kit, a tried and tested and accurate method.
The method
According to Amjad K. Balange, senior scientist from the Fisheries Resources Harvest and Post Harvest Management Division of CIFE, who carried out the tests with principal scientist B.B. Nayak, the paper strip from the kit is rubbed on the surface of the fish a few times and a drop of solution mixed with a reagent from the kit is put on it.
“The reaction takes place within two minutes. If the strip remains unchanged or becomes slightly grey, it means that there is no formaldehyde. If the strip turns light blue, it means slight contamination of formaldehyde and a dark blue colour means high contamination,” Mr. Balange said.
He said the kits are equipped to detect formaldehyde level of 4ppm and above. “Almost all fish have presence of formaldehyde in their body naturally. If they are laced with additional formaldehyde, the level most probably will be 4ppm or above. Thus, these kits are reliable to understand contamination if any,” he said.
Ingesting large amounts of formalin can cause abdominal pain, vomiting, coma, renal injury and possible death. The International Agency for Research on Cancer of the World Health Organisation has classified formaldehyde as ‘carcinogenic to humans’ with sufficient evidence for causing nasopharyngeal cancer with occupational exposure, although no carcinogenicity has so far been established through the ingestion route.
Fish traders get easy access to the chemical and are often forced to use it due to lack of good quality ice harvest centres and warehousing facility for bulk storage.
(With inputs from Esha Mitra)
