Studies have revealed heavy metals and pesticides residue in common vegetables and fruits in Bangladesh above permissible levels, posing serious health risks for people, especially for children and women.
The studies were conducted by Bangladesh Agricultural University and Bangladesh Agricultural Research Institute (BARI) and funded by Bangladesh Food Safety Authority (BFSA).
The study on vegetables found above permissible level of cadmium, chromium, led and cobalt in eight vegetables, including potato. Pesticide residues were found on a large scale in staple fruits.
The key findings of the studies were disclosed at a research dissemination programme organised by BFSA at its auditorium in the capital on Sunday.
The study titled 'heavy metal in vegetables and associated human health risk management' was led by Professor Shafiqul Islam and Dr Mohammad Ghulam Kibria of BAU.
The researchers collected samples from six districts in Dhaka and Mymensingh divisions and tested nine types of vegetables, including potato, brinjal, okra, tomato, cabbage, cucumber and country beans.
Several vegetables, including brinjal, country beans, cucumber, okra, pointed gourd, and red amaranth, contain high levels of harmful heavy metals such as lead, chromium and cadmium.
Among these, the highest levels of contamination were detected in red amaranth.
According to the researchers, long-term consumption of vegetables contaminated with heavy metals poses serious health risks, including cancer.
Samples of potatoes, brinjal, okra, tomatoes, red cabbage, pointed gourd, cabbage, cucumber, and beans were collected from various district markets and tested.
Red amaranth was found to contain 704.32 micrograms of cadmium per kilogram or kg, far exceeding the maximum tolerable level of 190 micrograms a kg.
Other vegetables such as brinjal (275.66 micrograms/kg), cucumber (349 micrograms/kg), and tomato (195 micrograms/kg) also showed dangerous levels of cadmium, with the highest contamination found in samples collected from Narayanganj district.
The concentration of heavy metals (As, Cd, Pb, Cr, Ni, and Co) in vegetables varied widely across the six districts of Bangladesh.
Among the selected heavy metals, lead and cobalt concentrations in all the vegetables were found to be above the permissible limit, while cadmium levels exceeded the limit in most of the collected samples.
In contrast, arsenic and nickel concentrations remained below the permissible limit in all the vegetables from the study areas.
Meanwhile, tests on 320 samples of mango, litchi, Indian plum (ber) and guava revealed pesticide residues at harmful levels in approximately 10 percent of the samples.
Meanwhile, senior scientific officer of the Bangladesh Agricultural Research Institute (BARI), Dr Mohammad Delwar Hossain, led the research titled "Monitoring of Pesticide Residues and Their Associated Health Risk Assessment in Fruits".
His team tested 320 samples - 80 each of mango, litchi, Indian plum (ber), and guava. Pesticide residues were found in 39 samples, accounting for 12.19 per cent of the total. The highest pesticide contamination was detected in litchi (18.8 per cent), while mango had the lowest (8.8 per cent).
The fruit samples were collected from Dhaka, Rajshahi, Pabna, and Bogura. Of the contaminated samples, 30 exceeded the maximum residue limit (MRL).
Chairman of BFSA Md Zakaria, Prof Md Iqbal Rouf Mamun of Dhaka University, Dr Shamsad Begum Quraishi of Bangladesh Atomic Energy Commission, also spoke on the occasion.
Researchers, however, observed high variation in the concentration of heavy metals in vegetables was observed across the six districts of Bangladesh, largely due to differences in soil contamination.
Vegetables should not be grown in contaminated areas, and surface and groundwater near industrial sites should be avoided for irrigation.
Red amaranth, which showed a high accumulation of most heavy metals, should not be cultivated in such areas.
It is crucial to screen vegetables and develop varieties with lower uptake of heavy metals like As, Cd, Cr, Pb, and Ni to reduce health risks.
Awareness campaigns should be promoted to discourage the consumption of vegetables from contaminated areas, and the BFSA should enforce regulations and conduct regular surveillance at market hubs to assess cultivation areas, said the researchers in recommendations.
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