Kolkata, June 21 -- A team of scientists from Imperial College London and Jadavpur University has identified a naturally occurring soil bacterium, Bacillus subtilis, that can help tackle two major agricultural and public health challenges - arsenic contamination in rice and the spread of antibiotic-resistant bacteria in farmland.

The researchers found that the harmless bacterium, commonly present in healthy soil, produces a sticky coating known as a biofilm that traps arsenic and prevents it from reaching rice roots. It also produces a natural antibiotic-like substance called sublancin, which kills drug-resistant bacteria in the soil without harming beneficial microbes.

"Every year, millions of farmers in West Bengal, Bihar and Uttar Pradesh unknowingly grow rice in arsenic-contaminated soil. At the same time, antibiotic-resistant 'superbugs' are spreading through the same farmlands.

This is a single natural solution to tackle both these issues," said Arnab Majumder, principal investigator at Imperial College London, who led the study.

Scientists involved in the project said the intervention is particularly significant because it does not rely on chemical treatment. "Nature has already built the tool. We are simply learning to use it at the right temperature, at

the right time," Majumder added.

The study found that at temperatures between 30degC and 35degC - conditions increasingly common in India due to climate change - the bacterium becomes more effective, trapping up to 74 per cent more arsenic and producing the highest levels of sublancin. This temperature range aligns with projected warming scenarios for the Indo-Gangetic Plain.

More than 50 million people in India are estimated to be exposed to arsenic-contaminated groundwater, with West Bengal among the worst-affected regions.

Prof Tarit Roychowdhury of Jadavpur University, who led the field trials in West Bengal, said the results were validated under real farming conditions in the Gangetic delta.

The findings have been published in the Journal of Hazardous Materials. Scientists, however, cautioned that large-scale field deployment will require further testing.

Published by HT Digital Content Services with permission from Millennium Post.