BAU's new irrigation method cuts arsenic in rice by 40%, saves water

Researchers at Bangladesh Agricultural University (BAU) have introduced a new irrigation technique, named 3F4D, aimed at reducing arsenic levels in rice.

According to the research, the 3F4D method can reduce inorganic arsenic levels in rice by up to 40 percent, while also saving 65 to 80 percent of the water used for irrigation.

The research was conducted under the project titled ‘Development of Breeding and Water Management Technologies for Safe and Nutritious Rice Production’ with technical support from the Japan International Cooperation Agency (JICA).

Dr Md Rafiqul Islam, a professor in the Department of Soil Science at BAU, stated on Wednesday (May 7), "Symptoms of arsenic poisoning include spots on the body, nausea, bright red mucous membranes, and severe diarrhea. Long-term exposure can lead to serious health issues such as cancer, and kidney and liver failure. The severity of arsenic contamination in the country's groundwater is worsening due to environmental pollution. Since water is crucial for rice cultivation, arsenic tends to accumulate in rice through the food cycle. However, the concentration of arsenic in rice varies due to differences in arsenic levels in water across regions."

He explained that the newly developed 3F4D method ensures the production of safe rice without compromising yield. By significantly reducing the use of irrigation water, this approach offers a practical solution for safeguarding public health and promoting sustainable rice production in regions affected by groundwater pollution.

"The study examined the impact of arsenic over three consecutive Boro seasons, comparing the effects of the 3F4D, 3F7D, mid-season drainage, and no drainage methods. The results of these methods were also contrasted with those of conventional continuous waterlogging and alternative waterlogging and drainage (ADWB) methods," he added.

The results revealed that with the 3F4D method, soil moisture decreased by approximately five percent after four days of drainage, and the redox potential (electrical measurement) increased to between 150 and 500 millivolts. This created an oxygen-rich (oxidative) environment, which effectively reduced arsenic absorption by rice plants.