But when Rahman returned home, he was shocked. The mangos were too sour to eat. The flavor of the mangos was also quite strange. "I have read in the newspapers that they use chemicals in fruits, but I couldn't believe I would become a victim," said Rahman.

'Madhumas,' the month of sweet fruits, is back again. But so are the unscrupulous traders trying to make a cheap variety of unripe fruits look ripe, juicy and of high quality in order to sell them at exorbitant prices.

The fruits of madhumas include mangos, jackfruit, lychees, watermelon, pineapple, papaya and banana, which are now to be found in the city's markets and bazars. But it is widely alleged these days that the fruits are artificially ripened using harmful chemicals. In addition, unscrupulous traders try to attract and deceive customers by using toxic colors. Vegetables and fish are also subject to various adulteration processes.

To ripen fruit artificially, a chemical named ethylene oxide is widely used. After using ethylene, green fruits automatically enter a ripened stage due to a bio-chemical reaction. On the outside the fruits looks attractive.

"All ripe fruits produce ethylene oxide naturally. But the artificially-made chemical that is used to dodge the immature stage is very harmful. The additional levels of ethylene causes cancer," said Dr MZH Bhuiyan, Director of the Institute of Food Science and Technology (IFST)

Meanwhile, the Ministry for Industry has requested the Bangladesh Standards Testing Institute (BSTI) to investigate the problem. However, senior officials of BSTI said, "We are allowed to inspect only processed and packaged food products. Fruits and vegetables are not listed by us as authorized items."

"The Department of Agriculture should take the responsibility because the suspected items are agricultural products," they suggested.

But the use of chemicals is not restricted to agricultural products such as fruits and vegetables. It has also been alleged that some dishonest traders tarnish fish using formaline, a chemical that keeps the fish fresh-looking. Formalin is usually used in morgues to keep dead bodies from rotting.

Dr. Bhuyan told Starcity, "Formalin is a kind of poison. High doses of it can cause death. If some traders are using formalin with fish, then the poison will act slowly in the human body, a process called 'slow-poisoning.'"

Dr. Bhuyan warned that regular consumption of food contaminated with chemicals can cause severe diseases in the long term. Legislation must be implemented to stop the adulteration of food with harmful chemicals, he added.