Prelims: Current events of national and international importance | Environment
Why in News?
Recently, scientists at the IIT Guwahati have developed a biological material using cyanobacteria (blue-green algae) that can remove lead from contaminated water.
- Cyanobacteria (blue‑green algae) – Commonly found in ponds, lakes, reservoirs, paddy fields, and slow‑moving fresh water bodies.
- Material – Exopolysaccharides (EPS), a sticky, sugar‑rich substance secreted by algae.
- EPS Mechanism – Blue‑green algae grow in ponds or paddy fields; their cells secrete sticky, sugar‑rich EPS molecules that naturally bind lead.
- Algae further adjust their composition to trap and hold lead particles.
- Efficiency – EPS can remove 66.2% of lead, one of the most toxic heavy metals present in water.
- Additional Benefits – Cyanobacteria form cyanolichens with fungi, enrich soil, fix nitrogen as a natural biofertiliser, and boost agricultural productivity.
- Conventional Methods – Traditional methods like chemical precipitation, membrane filtration, and ion exchange are costly, energy‑intensive, and polluting.
- Biological approaches offer greener, renewable, and eco‑friendly alternatives.
Reference
The Hindu | Blue-green algae can remove lead from water
