The American Chemical Society (ACS), one of the world’s largest scientific societies, has identified the presence of cadmium in rice, beyond permissible levels, a finding also supported by the country’s scientists. The cereal is the main staple of 160 million Bangladeshis. The ACS recently conducted research on rice samples from Bangladesh, Sri Lanka, Cambodia, Ghana, India, Italy, Japan, Nepal, Spain, Thailand, the US and France.
According to the ACS study, Bangladesh has the dubious distinction of topping the list among the 12 countries, while Sri Lanka has secured the second position.
The ACS study shows the presence of 0.01 to 0.3 parts per million (ppm) of cadmium per kilogram in Bangladeshi rice. It noted that this trend was rising. It further said that high cadmium content in rice was found in some places of Bangladesh, but not across the country.
Cadmium reacts with calcium and people may suffer from cancer and diseases of the heart, lungs, kidneys and bones, if cadmium is present in food, the scientists said.
Prof. Zahir Uddin of the Bangladesh Agricultural University (BAU) was associated with the study, which was carried out in Rangpur region last year.
“This requires further studies, since it is an initial finding. We apprehend that the presence of cadmium in this region is high. Phosphate fertilisers are the major culprit responsible for the presence of this heavy matter in rice grain, which is highly cancerous,” the researcher said.
He added that a huge quantity of cadmium is deposited in the soil of lower Bangladesh, which is the rice bowl of the country, along with the northern plains.
Prof. Imamul Huq, former chairman of the Bangladesh Council of Scientific and Industrial Research (BCSIR), said, “Untreated industrial effluents are also responsible for the deposits of cadmium in the soil. Cadmium enters the rice through the plants from contaminated water in the fields.”
Untreated tannery wastes are being directly dumped into rivers, canals and crop fields, he pointed out, adding that different dyeing and garments factories are also responsible for producing cadmium-rich wastes, which find their way into wetlands, where rice is grown.
Prof. Huq further said the World Health Organisation’s (WHO’s) permissible limit of cadmium in rice, is a maximum of 0.22ppm.
“Stopping its sources is the only way of preventing cadmium from entering human bodies. Japanese scientists have also suggested raising soybean on cadmium-contaminated soil, but this soybean must be destroyed and should not be used for human consumption, as well as for use by fish, livestock and poultry,” said Prof. Huq, who is also a soil expert.
Prof. Dr Mahbubar Rahman, vice-chancellor of Bangabandhu Sheikh Mujibur Rahman Agricultural University, said, “The presence of cadmium in food is very normal, but, it is a worrying matter that cadmium above permissible limits has been found.”
Cadmium is a heavy metal, he said, adding, “Industrial wastes produce heavy metal and cadmium comes from untreated industrial effluents.” Dr Mala Khan, a senior scientific officer of BCSIR, said cadmium does not exist in normal soil. However, many electronic objects, such as batteries, cause cadmium deposits in the soil.
“It is a toxic matter. It would affect the human body if it exists above permissible limits in food,” the scientist observed.
Dr Gazi Zainal Abedin, senior scientific officer of Soil Resource Development Institute (SRDI), said that in a survey of the much-used fertilisers available in markets across the country, some 14 out of 17 samples have been found to be adulterated, last year.
He said that the percentage of adulterated fertilisers as per SRDI report were: urea, 2 per cent; triple super phosphate (TSP), 25 per cent; di-ammonium phosphate, 21 per cent; single super phosphate (SSP), 33 per cent; muriate of potash (MOP) 11 per cent, mixed fertiliser, (NPKS) 80 per cent; zinc sulphate, 80 per cent; sulphate of potash (SOP), 30 per cent; boron, 40 per cent; magnesium sulphate, 14 per cent; gypsum, 21 per cent; organic matter, 47 per cent; and other fertilisers, 29 per cent.
Such adulterated fertilisers are also responsible for the deposits of cadmium in the soil, which may contaminate the soil. Cadmium may enter the food chain through plants, the SRDI scientist observed.
-With The Independent input
