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Context:

India faces an escalating crisis of environmental degradation, where air, water and soil contamination are eroding the quality of life. Traditional clean-up approaches are costly and often generate secondary pollution, making biological solutions increasingly essential. Bioremediation—using living organisms to detoxify polluted environments—has emerged as a sustainable and scalable alternative.

What is bioremediation?

Bioremediation literally means “restoring life using biology.” It relies on microorganisms such as bacteria, fungi, algae, and plants to break down or immobilise pollutants like oil, pesticides, plastics, and heavy metals.
These organisms metabolise contaminants as food, converting them into harmless by-products such as water, carbon dioxide, or simple organic acids. Some microbes can also transform toxic metals into non-leaching forms, reducing their mobility in soil and groundwater.

Types of Bioremediations:

In Situ Bioremediation: Pollutants are treated directly at the contaminated site without excavation. Examples: oil-eating bacteria sprayed on marine spills or microbes injected into polluted aquifers.

Ex Situ Bioremediation: Contaminated soil or water is removed and treated in controlled facilities (bioreactors, biopiles) and returned once detoxified. This method allows better control of microbial growth conditions.

How bioremediation works?

Creating conditions for microbial action: Bioremediation works by either adding specialised microorganisms to a polluted environment or by modifying local conditions so that naturally occurring microbes can thrive. The goal is to encourage microbial activity that targets specific contaminants.

Harnessing the natural abilities of microbes: This approach relies on the inherent capacity of bacteria, fungi, algae and certain plants to dismantle harmful substances. These organisms have evolved biochemical pathways that allow them to use pollutants as food or nutrient sources.

Microbial metabolism of contaminants: During bioremediation, microbes metabolise toxic compounds, using them for energy or growth. As they consume these contaminants, they initiate a series of biochemical reactions that break down complex chemicals into simpler, non-toxic compounds.

Conversion into harmless end products: The pollutants are ultimately transformed into environmentally benign substances such as water, carbon dioxide, simple organic acids or mineral forms. These end products can be safely reabsorbed into the surrounding soil, air or water.

Why India needs bio-remediation?

India’s rapid industrialisation, urban expansion, and population growth have pushed ecosystems to a tipping point. Pollution now affects 70% of surface water, over 30% of groundwater blocks, and nearly one-third of India’s land shows signs of degradation (CPCB & ICAR). Conventional remediation technologies thermal treatment, incineration, chemical oxidation are costly, energy-intensive, and often produce secondary pollution. Bioremediation, by contrast, offers a biological, decentralised, and sustainable solution for restoring ecosystems at scale. 

Water pollution crisis

• CPCB data (2023) shows that over 72,000 MLD of sewage is generated, while treatment capacity is only ~32,000 MLD.
• Rivers like the Ganga, Yamuna, Sabarmati, and Musí receive massive loads of untreated wastewater, industrial toxins, heavy metals, and pharmaceutical residues. 

Soil contamination

• India generated 62 million tonnes of solid waste annually (MoHUA, 2022), with landfills leaching toxins into soil and groundwater.
• Agricultural soils across Punjab, Haryana, and Andhra Pradesh show pesticide residues far exceeding FAO safety limits. 

Industrial hotspots

• Oil leaks from refineries, petrochemical complexes, and ports (e.g., Ennore, Visakhapatnam, Mumbai) create persistent contamination.
• Ennore Creek, Tamil Nadu: A 2017 oil spill resulted in widespread ecological damage. Indigenous oil-eating bacteria such as Alcanivorax and Pseudomonas were deployed in subsequent remediation experiments, improving recovery speed.

Bioremediation as an economically viable option:

Bioremediation costs are 30–60% lower, depending on pollutant complexity.
It is especially suitable for large, diffuse contamination, where industrial-scale technologies become financially unfeasible.

What are the opportunities and risk associated for India?

What are the challenges associated in the adoption of bioremediation in India?

Lack of site-specific microbial and pollution profiles: Most Indian polluted sites have not been mapped for their microbial ecology, contaminant composition, or soil–water chemistry. CPCB (2022) identifies over 4,400 polluted river stretches, but fewer than 5–7% have undergone microbial profiling required for precision bioremediation.

Complex Mixtures of Pollutants: Indian waste streams often contain mixed contaminants heavy metals, pesticides, hydrocarbons, pharmaceuticals, making remediation harder.

Climatic Extremes Affect Microbial Survival: India’s environmental conditions—extreme heat, monsoon flooding, fluctuating pH—can reduce microbe survival. Optimal microbial performance typically occurs between 25–35°C, but landfill temperatures often exceed 50°C.

Absence of unified national standards: India lacks a centralised bioremediation protocol, similar to US EPA or EU standards. States follow their own guidelines, leading to inconsistent performance.

Unclear regulations for genetically modified (GM) microbes: India’s GMO laws focus on agriculture and pharmaceuticals, not environmental deployment. No dedicated guidelines exist for open-field release of engineered microbes. Approval processes are slow and risk-averse, discouraging innovation. 

How other countries are doing in bioremediation adoption?

Japan

Integrating Bioremediation into Urban Waste Systems. Japan systematically uses plant–microbe combinations (phytoremediation + bioremediation).

• Constructed wetlands in Tokyo and Osaka use native microbes to treat municipal wastewater.
• Soil bioremediation for industrial sites is supported by government subsidies.

European Union

The EU invests heavily through programs like Horizon Europe and LIFE+.

• Cross-border projects use microbial consortia to clean oil-contaminated coasts (e.g., Spain–Portugal–France Atlantic initiative).
• Former mining sites in Poland, Romania, and Bulgaria use fungi and bacteria to immobilise heavy metals.

China

China treats bioremediation as part of national soil policy.

• The Soil Pollution Prevention and Control Law (2019) mandates biological remediation options.
• Genetically enhanced bacteria are used to break down petrochemical waste in industrial parks.

Government initiatives supporting Bioremediation in India:

Support for Innovation and Startups through DBT–BIRAC

The Department of Biotechnology (DBT) and the Biotechnology Industry Research Assistance Council (BIRAC) have played a major role in building India’s bioremediation ecosystem.

• Through the Biotechnology Ignition Grant (BIG) and other early-stage funding schemes, the government provides financial support, incubation facilities, and mentoring to startups developing microbial formulations, enzymatic cleaners, biosensors, and waste-to-value solutions.
• These funds encourage translation of laboratory discoveries into on-ground technologies, bridging the gap between research institutions and industry. 

National River Conservation Plan (NRCP)

• Under NRCP, several polluted river stretches have adopted microbial consortia, constructed wetlands, and bio-augmentation techniques to improve water quality.
• Pilot projects have demonstrated reduction in Biochemical Oxygen Demand (BOD), foul odour, and sludge accumulation, especially in small tributaries and urban drains. 

Namami Gange Programme

Namami Gange has been a major testing ground for bioremediation.

• The programme has funded pilot-scale deployment of microbial treatments in drains feeding into the Ganga, especially in Uttar Pradesh and Uttarakhand.
• Bioremediation units—using bacterial cultures, enzymes, and floating treatment wetlands—have helped reduce organic pollution and improve dissolved oxygen levels in targeted stretches.
• These methods serve as interim or supplementary solutions until long-term infrastructure such as STPs is completed. 

Research and Field Implementations by CSIR–NEERI

The Council of Scientific and Industrial Research – National Environmental Engineering Research Institute (CSIR–NEERI) is at the forefront of bioremediation R&D in India.

• NEERI develops microbial consortia, biofilms, and enzyme-based technologies for treating sewage, industrial wastewater, oil spills, and contaminated soils.
• It collaborates with state governments and municipal bodies to conduct on-ground pilots in drain restoration, biomining of landfills, and sludge reduction. 

Conclusion:

Bioremediation offers India a promising pathway to restore polluted ecosystems in a cost-effective and sustainable manner. With strong regulation, scientific investment, and public participation, it can transform India’s approach to environmental management and support a cleaner, healthier future.

Source: The Hindu