A variety of vegetables available in city markets can pose serious health hazards as they have been found to be high in toxic content.

The root cause? Rampant use of banned pesticides.

A recent study by the Chittaranjan National Cancer Institute has revealed that many vegetables, instead of providing nutrients to the body, can irreparably damage several biological functions.

The bulk of the vegetables sold in the city are sourced from the districts covered by the study — North and South 24-Parganas, Howrah, Hooghly, Nadia, Burdwan and the two Midnapores.

“The pesticide remains in vegetables can cause neurological and blood disorders, lung ailments and affect the reproductive system of women. Agriculture workers are as prone to risks as consumers,” said Manas Ranjan Roy, the principal investigator of the study.

“The sharp rise in the number of patients suffering from Parkinson’s and Alzheimer’s, too, can be attributed to indiscriminate use of pesticides and air pollution.”

Prolonged exposure to raw pesticides (common among agricultural workers) or consumption of pesticide-infected vegetables can result in leukaemia and cancer of the skin, lips, stomach and prostrate.

“Around 99 per cent of individuals chronically exposed to agricultural pesticides suffer from more than one neurobehavioral problem, compared with 23.5 per cent among the rest,” said Sreeparna Chakraborty, a researcher.

Complaints of chronic fatigue, excessive sweating, tingling of limbs, persistent headache, muscle stiffness, blurring of sight and numbness in feet are “significantly higher” among those exposed to pesticides.

Pesticides can also cause loss of weight and appetite, irritability, insomnia and other behavioural disorders. Among women, the most likely effects are irregular menstruation, abortion and stillbirth.

Experts have also warned about the presence of bacteria, such as Salmonella (typhoid and para-typhoid) and E coli (food poisoning), in vegetables grown at Dhapa.

The study has found that pesticides declared as “extremely hazardous” and “severely hazardous” by WHO are being widely used by farmers.

In the “extremely hazardous” category are methyl parathion (marketed as Folidol and Metacid) and phosphamidon (Chemidon 40 SL). In the other group are carbofuran (marketed as Tatafuran, Furadon), dichlorvos (Nuvan) and monocrotophos (Nuvacron, Monocil).

Officials blamed the laxity of the agriculture department for the violation of the ban on pesticides. “For effective implementation of the ban, there should be co-ordination among agriculture, health and environment departments. But such interface is absent,” said a health department official.

Agriculture department officials said they were not sure to what extent banned pesticides were being used. Sources said some distributors were supplying banned pesticides in collusion with a section of government officials.