Indian market traders are spray-painting and dying fruit to make it appear more natural and boost sales, it has been claimed.

Footage passed to The Independent shows a man at stall in Dehli applying the paint to a mound of unripe lychees.

Despite the filmmaker warning him of the dangers, the trader explains he cannot wait for them to ripen and needs the money to survive.

India's food adulteration epidemic has long been an issue of concern, with food safety officers warning that milk, oil and spices are most commonly altered, along with fresh fruit and vegetables.

In 2015, India’s food regulator found 20% of Indian food had been adulterated in some way or misbranded.

Dyes and chemicals are used by some farmers to disguise unripe or rotting fruits and vegetables, including known carcinogens malachite green and calcium carbide.

Produce can also be coated in silicone or wax to give it a fresh-looking shine and to act as a preservative.

Professor Anthony Dayan, retired toxicology academic from Barts hospital, said consumption of malachite green had particularly alarming health implications.

“Low doses of malachite green over a long period damage the liver and the kidneys, and are associated with cancer,” he told The Independent.

“Most industrial grades of malachite green may contain quantities of arsenic, it's not by any means a benign compound.”

He also questioned the motivation behind food alteration, asking: “What are you disguising underneath? Is it rotten? Is it covered with fungus? Is it fit to eat?

“The best case scenario is it will be unpleasant, and in the worst case, it could be very harmful indeed.”

Dr Vikram Patel, Professor of International Mental Health at the London School of Hygiene and Tropical Medicine, said farmers were facing crippling pressure to stay in business, which pushes some to drastic measures to increase the yield they send to market.

“Indian farmers are in considerable distress," he told The Independent.

“Many of them have very small holdings and are increasingly finding competition from larger agricultural operations.

“Globalisation of agriculture threatens the livelihood of farmers which, along with climate uncertainty, makes farming a risky profession.

“I wouldn't be surprised at all if farmers were resorting to this measure.”

Calcutta resident, who asked to be identified only as Ramma M, told how difficult it was to buy produce at her local market for fear it had been contaminated with toxic chemicals.

She told The Independent: "I've seen vendors locally merrilly dipping vegetables in a bucketful of green colour, one can see clearly that it is dye.

"I have protested time and again but I never get a response.

"The only choice left for people like me who don't want to eat these chemicals is we don't buy them if we see buckets of dye nearby.”

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