MARGAO: In a shocking revelation, the first fish formalin report of July 12, 2018 that had blown the lid off the import of carcinogenic formalin laced fish into the State has been accessed under RTI, and Herald investigated the claims made in the report and observed certain discrepancies.
First, the report (which was subsequently overridden by another updated report which became the basis of FDA Minister Vishwajit Rane’s statement of formalin being within permissible limits) is actually a testimony of how Goa government failed to act even when the alleged kingpin had confessed.
Page 2 of the report titled “Raid at Wholesale Fish Market, Margao, Goa to check the presence of Formalin in Fish” reveals that FDA Chemist Pundalik Gawde tested fish samples randomly from all the 17 vehicles and the prescribed Schiff’s Reagent Test revealed that all the samples from all trucks showed dark pink to purple colour which is a positive test for formalin. The darker the colour the more is the concentration of formalin. All this despite the fact that fishes being preserved in a mix of ice and formalin and yet the level of concentration of formalin in fish was high.
More shocking details emerged thereafter. The report says “Shri M. Ibrahim, President of Wholesale Fish Market Association, Partner of Quality Exports situated at Cuncolim IDC, informed that he is taking the responsibility of all the vehicles, detained by us”. Despite this, Goa Police never detained Ibrahim nor did the State government find his trade harmful to the people of Goa.
However, the most blatant shocker is when the report says, “He insisted on the second analysis report put from FDA laboratory”. The second laboratory report which was revealed to the public talked of formalin within permissible limits and a clean chit for the formalin laced fish import business in Goa.
How accurate is the Schiffs Reagent Test?
The Schiffs test is very accurate at extremely lower levels of concentration of formaldehyde, also called formalin. The spot report stated that that the samples showed dark pink to purple colour. Levels of formalin below 5ppm or micrograms per litre result in light pink colour, whereas higher the concentration, the colour changes to dark pink (magenta) to violet, which is often confused with purple colour.
The Schiffs Reagent Test was developed in 1866 by H Schiff as spot test for formaldehyde using basic fuschin and sulfur dioxide. Over the years the test improved with the use of pure para-rosaniline hydrochloride, the chemical that creates the shades of pink color through the reaction of para-rosaniline, formaldehyde and sulfur dioxide. The test was specifically designed for formaldehyde at extremely low concentrations, however, it can detect other aldehydes at higher concentration. More importantly, the test doesn’t show a false positive. The colour of the solution does not change to pink with any chemical other than aldehyde. So any claims by Ibrahim that the test is faulty is completely baseless.
Could Schiffs Reagent detect any other Aldehyde as claimed by the FDA director?
The Shiff’s Test is extremely selective and virtually specific for formaldehyde. This was clearly stated in a research paper titled ‘Quantitative Determination of Formaldehyde in the Parts Per Hundred Million Concentration Level’ published in the Journal of the Air Pollution Control Association published in 2012 tested Shiff’s Reagent on several aldehydes such as cinnamaldehyde, crotonaldehyde, butryaldehyde, chloroacetaldehyde and many others. It was revealed that higher aldehydes failed to give positive reactions even in 10% concentrations. Only two aldehydes gave positive reactions, acetaldehyde and propionaldehyde. Acetaldehyde and propionaldehyde are detected with the concentration levels were five ppm. Lower concentrations gave no detectable response.
This implies that unless the higher concentration of other aldehydes were added by the suppliers deliberately, since Shiff’s Reagent would not test positive for the fish for aldehydes other than formaldehyde.
