Low-arsenic rice discovered in Bangladesh
Scientists identify aromatic rice with very low arsenic content and higher concentrations of essential nutrients, selenium and zinc – published in Biomedical Spectroscopy and Imaging
Millions of people worldwide are regularly exposed to arsenic through drinking water and eating rice grown in soil and water containing high amounts of arsenic. Long-term exposure can lead to the development of different types of cancer as well as serious cardiovascular, neurological, and other health problems. Scientists have now identified aromatic rice from Bangladesh that has far lower arsenic concentrations than found in non-aromatic rice. The other important benefit is that it contains higher amounts of selenium and zinc. The discovery is reported in Biomedical Spectroscopy and Imaging.
Rice is the staple food of over three billion people. Because the rice plant is highly efficient at absorbing arsenic from soil and water, it is reported to be the highest arsenic-containing cereal. For Bangladeshis, rice is their staple food and they consume on average half a kilogram of rice daily.
A team of scientists led by Dr. Parvez Haris from De Montfort University, Leicester, UK is carrying out research to remove arsenic from water and to identify ways of reducing human exposure to arsenic through diet.
Haris and his team have already demonstrated that exposure to the more toxic inorganic arsenic species is greater in people who eat more rice. In this latest work, published in Biomedical Spectroscopy and Imaging, the De Montfort University team – along with Dr Michael Watts from the British Geological Survey, Keyworth, Nottingham, UK – has identified varieties that are low in arsenic but high in essential trace elements such as selenium and zinc.
Earlier studies showed high concentrations of arsenic in Bangladeshi rice, but the rice samples were mainly from regions where the irrigation water contains higher levels of arsenic. The team carried out a detailed study on rice from the greater Sylhet region in the north-east of Bangladesh, which generally has a lower groundwater arsenic concentration. The team analyzed 98 rice samples using a technique called Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) to determine total arsenic and also arsenic species in a selected group of samples.
The results showed Sylheti rice to have a far lower arsenic concentration than similar types of rice from other regions of Bangladesh. Results also showed that the arsenic concentration in aromatic rice was 40% less than non-aromatic varieties and that it also contained higher concentrations of the essential elements selenium and zinc.