IIT Guwahati Research Uncovers How Blue-Green Algae Can Remove Lead from Water
Publish Date:08-07-2026
IIT Guwahati Research Uncovers How Blue-Green Algae Can Remove Lead from Water
· The research provides a sustainable and environment friendly method of solve lead contaminated water challenge in the country
GUWAHATI, 8th July 2026: Indian Institute of Technology Guwahati researchers have developed a biological material that can remove lead from contaminated water.
According to a report released in 2020 by UNICEF and Pure Earth, more than 275 million children in India had blood lead levels at or above hazardous levels. Another report from Central Ground Water Board (CGWB) revealed that over 20 to 30 percent of groundwater samples tested across major Indian cities were found to exceed the World Health Organization's safe limits.
Though there are multiple conventional water treatment methods, which use chemical precipitation, membrane filtration, or ion exchange processes, they are often expensive, consume large amounts of energy, and generate secondary pollutants. Due to such limitations, researchers around the globe are working towards finding an environmentally friendly and renewable alternative for this problem.
In a first-of-its-kind study, the IIT Guwahati research team, led by Prof. Debasish Das, Professor, Dept. of Biosciences and Bioengineering, has identified cyanobacteria, commonly known as blue-green algae, that can be used to absorb lead from contaminated water. A key feature of this approach is the vast availability of these algae, in village ponds, lakes, reservoirs, paddy fields, and slow-moving freshwater bodies.
Based on their research, the team found that the sticky, sugar-rich material found in algae, called exopolysaccharides (EPS), absorbed the highest amount of lead from water.
Explaining findings of the research, Prof. Debasish Das, said. “In our recent study, we found that EPS organism can remove lead (66.2%), one of the most toxic heavy metals, from polluted water. It can form associations with fungi to form cyanolichens, enrich soil by fixing nitrogen, and act as a natural biofertiliser to boost agricultural productivity.”
To understand how the EPS absorbs lead from water, the researchers used different techniques to examine the material's composition and its interaction with lead. They found that naturally occurring chemical groups in the material bind lead particles, making it effective at removing lead from contaminated water. The research team also found that blue-green algae naturally changes its chemical composition to capture lead.
The findings of this research have been published in the Journal of Environmental Chemical Engineering, in a paper co-authored by Prof. Debasish Das along with Prof. Tapas Kumar Mandal, Professor, Department of Chemical Engineering, and Dr. Abhijeet Mahana, Postdoctoral Fellow at IIT Guwahati.
As the next step, the research team plans to evaluate the performance of EPS using real industrial wastewater containing mixtures of toxic metals. The team also plans to work upon recyclability of the biosorbent and develop a scalable system that can be used for continuous water treatment.
In controlled laboratory experiments, the exopolysaccharides (EPS) produced by blue-green algae successfully removed up to 66.2% of toxic lead from contaminated water.
Disclaimer - The research described in this release is at a laboratory stage. The findings are subject to further validation and should not be interpreted as final or ready for commercial application.
