IIT-G Develops Low-Cost Natural Method to Remove Lead from Water Using Cyanobacteria

On November 29, 2025, researchers from the Indian Institute of Technology (IIT) Guwahati announced a groundbreaking development in environmental science: a sustainable and low-cost method for removing lead from contaminated water using cyanobacteria. This innovative approach addresses one of the world’s most pressing environmental issues, particularly the contamination of water resources.

Understanding the Problem of Lead Contamination

Lead is recognized as one of the most toxic pollutants, with serious health implications affecting over 800 million children globally, including approximately 275 million in India alone. Lead commonly enters water systems through various means:

• Industrial discharge
• Agricultural runoff
• Old and deteriorating water pipelines

Once introduced into water bodies, lead can persist for decades, accumulating in living organisms and leading to severe health problems, including:

• Neurological issues
• Cardiovascular diseases
• Kidney damage
• Developmental disorders in children

Traditional Methods of Lead Removal

Conventional methods for removing lead from water typically involve chemical treatments and synthetic absorbents. However, these methods often come with significant drawbacks:

• High costs
• Generation of secondary pollutants

These limitations highlight the urgent need for more effective and sustainable solutions to combat lead pollution in water resources.

Bioremediation: A Natural Solution

To tackle the challenges associated with lead contamination, the research team at IIT Guwahati turned to bioremediation—a natural process in which microorganisms, such as cyanobacteria, clean up contaminated environments. Cyanobacteria are photosynthetic microorganisms that naturally occur in soil and water, playing a vital role in restoring ecological balance.

The Role of Phormidium corium NRMC-50

The researchers specifically focused on a light-dependent lead-bonding cyanobacterial species known as Phormidium corium NRMC-50. The team conducted extensive research on different components of this cyanobacterium to identify which parts were most effective at absorbing and removing lead contaminants from water.

The study revealed that exopolysaccharides (EPS), a component of the cyanobacterium, exhibited an impressive lead removal efficiency of 92.5% from contaminated water. This high efficiency demonstrates the potential of using cyanobacteria as a natural biosorbent for lead removal.

Advantages of the Cyanobacterial Method

According to Professor Debasish Das, a co-author of the study, the cyanobacterial biosorbents offer several advantages:

• Minimal energy input required
• Scalability without the need for sophisticated infrastructure
• Overall treatment costs estimated to be 40-60% lower than conventional methods
• Comparable or superior efficiency in metal removal

This economic benefit, combined with the eco-friendly nature of the method, positions it as a sustainable alternative for industries and municipalities seeking affordable solutions to water contamination.

Environmental Benefits Beyond Lead Removal

The potential of cyanobacteria extends beyond lead removal. The researchers demonstrated that these microorganisms can also absorb various environmental pollutants, including:

• Pesticides
• Herbicides
• Hydrocarbons
• Synthetic dyes
• Industrial chemicals

Furthermore, the metals absorbed by the cyanobacteria can be recovered and transformed into valuable products such as bio-char, bioplastics, or biofuels. This aspect adds an economic incentive to the bioremediation process, making it not only a solution to pollution but also a potential source of sustainable materials.

Future Steps and Implementation

Looking ahead, the research team at IIT Guwahati aims to scale the process from laboratory settings to pilot-scale treatment systems. The next phase involves testing the method in real wastewater streams to evaluate its effectiveness in practical applications.

The researchers are optimistic about the potential impact of their findings on environmental remediation practices, particularly in regions heavily affected by lead contamination.

Conclusion

The development of a low-cost, natural method for removing lead from water using cyanobacteria marks a significant advancement in the field of environmental science. By leveraging the natural capabilities of microorganisms, this approach not only addresses a critical public health issue but also offers a sustainable solution that can be implemented on a larger scale.

Note: The findings of this research have been published in the Journal of Hazardous Materials and highlight the importance of innovative solutions in combating environmental challenges.