Engineering Enzymes to Break Down Microplastics in Sewage and Wastewater

At Bioglobe, our commitment to pioneering enzyme-based solutions for raw sewage remediation is unwavering. As the global environmental crisis intensifies, one of the most pressing challenges we face is the persistent contamination of water systems with microplastics. These tiny plastic particles, often less than 5 millimetres in size, originate from larger plastic debris degrading or are deliberately manufactured at small scales — and they have now become ubiquitous in waterways worldwide. Recent scientific breakthroughs, such as those achieved by researchers at Cornell University, have introduced exciting new possibilities for tackling microplastic pollution using engineered enzymes.

In this article, we explore the cutting-edge development of novel enzymes capable of breaking down polyethylene terephthalate (PET) plastics in the harsh and complex conditions found in sewage sludge. We examine how this advancement complements Bioglobe’s mission to transform raw sewage into clear, organic water and its potential implications for the future of wastewater treatment.

The Microplastic Menace in Water Systems

Microplastics have become a global environmental concern due to their persistence and harmful effects on aquatic ecosystems, human health, and food safety. These particles are now detected not only in oceans but also in freshwater systems, soils, and even atmospheric dust. Their small size allows them to be ingested by marine life and enter the food chain, raising alarm over bioaccumulation and toxic effects.

Wastewater treatment plants (WWTPs) are often the first barrier preventing microplastics from entering natural waterways. However, current treatment processes are not fully effective at removing all microplastic contaminants. Many particles escape treatment and are discharged into rivers, lakes, and oceans, further exacerbating pollution. This problem is compounded by the complexity of sewage sludge, which contains a mixture of organic matter, microbes, chemicals, and microplastics — creating an extremely challenging environment for plastic degradation.

Polyethylene Terephthalate (PET) and Its Role in Microplastic Pollution

Polyethylene terephthalate, or PET, is one of the most widely produced plastics globally. Used extensively for packaging, especially in bottles and containers, PET is prized for its durability, clarity, and recyclability. Despite these qualities, PET is a significant contributor to microplastic pollution due to improper disposal and fragmentation over time.

Because PET is resistant to natural degradation, it accumulates in the environment, breaking down only very slowly under sunlight and mechanical forces. The challenge for wastewater treatment is to develop effective methods for breaking down PET particles at the micro or even nano scale, preventing them from being released back into water systems.

Traditional Approaches to Microplastic Removal

Conventional wastewater treatment involves physical filtration, sedimentation, and chemical treatment processes designed primarily to remove organic matter and pathogens. While effective in many respects, these methods are less successful in targeting microplastics due to their small size and diverse chemical properties.

Mechanical filtration can capture larger microplastic particles, but smaller particles often pass through. Chemical treatments are not selective enough and can lead to secondary pollution or damage beneficial microbial communities. As a result, the presence of microplastics in treated effluent remains a significant issue.

The Promise of Enzyme-Based Remediation

Enzymes are biological catalysts that accelerate chemical reactions without being consumed in the process. They offer remarkable specificity and efficiency, making them ideal candidates for targeted pollution remediation. Enzyme-based approaches to wastewater treatment are increasingly attractive because they can operate under mild conditions, reduce reliance on harsh chemicals, and promote biodegradation.

At Bioglobe, we have long championed enzyme technologies for organic remediation, transforming raw sewage into clear water by breaking down complex organic compounds safely and effectively. The emerging use of engineered enzymes to degrade plastics represents a significant extension of this capability.

Cornell University’s Breakthrough: Engineering a PET-Degrading Enzyme

A team of researchers at Cornell University has recently announced the successful engineering of a novel enzyme capable of breaking down PET plastics even within the complicated environment of sewage sludge. This is a remarkable advance given the difficulty of enzyme activity in sewage, where various inhibitors, fluctuating pH levels, and competing substances often hamper catalytic function.

What Makes This Enzyme Special?

The enzyme engineered at Cornell is a variant of PETase, a naturally occurring enzyme discovered in bacteria that can consume PET as a carbon source. The Cornell researchers employed protein engineering techniques to improve the enzyme’s stability, activity, and robustness so it can function efficiently in sewage conditions.

Key features include:

• Enhanced Thermal Stability: The enzyme maintains activity at the higher temperatures common in sewage treatment facilities.
• Resistance to Inhibitors: It is less affected by the diverse chemicals and microbial products present in sewage sludge.
• Increased Catalytic Efficiency: It breaks down PET polymers faster than previous natural or engineered variants.
• Capability to Target Microplastics: The enzyme effectively degrades PET particles at micro and nano scales, converting them into harmless by-products such as terephthalic acid and ethylene glycol.

How This Innovation Aligns with Bioglobe’s Mission

Bioglobe’s mission is to harness enzyme-based technologies to remediate raw sewage organically, turning contaminants into clear water free from harmful substances. The ability to incorporate PET-degrading enzymes into existing sewage treatment processes represents a powerful opportunity to address microplastic pollution, a stubborn and escalating environmental threat.

This enzyme could be integrated into our remediation systems at various points, such as:

• During Primary Treatment: Where large solids are removed, enzymatic treatment could begin breaking down plastic fragments early on.
• In Anaerobic Digestion or Sludge Treatment: The enzyme could enhance the breakdown of microplastics embedded in sludge, improving both water quality and sludge management.
• In Final Effluent Polishing: To remove residual microplastics before treated water is released or reused.

Environmental and Public Health Implications

Reducing microplastics in treated wastewater has far-reaching benefits:

• Protecting Aquatic Life: Microplastics are ingested by fish and invertebrates, causing physical harm and toxic effects.
• Safeguarding Human Health: Humans consume seafood contaminated with microplastics, and emerging research suggests these particles may pose health risks.
• Preserving Ecosystems: Microplastics disrupt natural processes and degrade habitats.
• Improving Water Quality: Cleaner water supports biodiversity, agriculture, and human use.

By advancing enzyme technologies capable of degrading microplastics, Bioglobe supports a cleaner, safer environment for all.

Challenges and Future Directions

While the Cornell breakthrough is promising, several challenges remain before widespread adoption:

• Scaling Production: Manufacturing engineered enzymes at industrial scale must be economically viable.
• Integration into Treatment Plants: Optimising dosage, delivery methods, and retention times is essential for effectiveness.
• Regulatory Approval: New biotechnologies must undergo rigorous testing to ensure safety and environmental compatibility.
• Comprehensive Microplastic Targeting: PET is a major microplastic component, but other polymers like polyethylene, polypropylene, and polystyrene require different approaches.

At Bioglobe, we are actively researching complementary enzymes and synergistic microbial communities to broaden the spectrum of degradable plastics.

Bioglobe’s Commitment to Innovation and Sustainability

Our leadership in enzyme-based remediation reflects a broader commitment to sustainable, eco-friendly water treatment technologies. By collaborating with academic institutions, investing in research, and continually refining our enzyme blends, we strive to stay at the forefront of innovation.

We envision a future where:

• Enzyme-enhanced sewage treatment plants are standard.
• Microplastic pollution is significantly curtailed.
• Communities have access to clean, safe water resources.
• Environmental restoration and industrial efficiency go hand in hand.

Conclusion

The engineering of enzymes capable of breaking down PET microplastics in sewage represents a significant milestone in environmental biotechnology. Cornell University’s breakthrough aligns seamlessly with Bioglobe’s vision to develop natural, enzyme-driven remediation solutions that turn raw sewage into crystal-clear water.

As we move forward, the integration of such innovations will be crucial in addressing the microplastic crisis, protecting ecosystems, and promoting human health. At Bioglobe, we remain dedicated to advancing enzyme technologies, ensuring cleaner water for future generations, and setting new standards for sustainable wastewater treatment.

For further information about Bioglobe’s enzyme remediation technologies and how we are revolutionising wastewater treatment, please contact us or visit www.bioglobe.co.uk.

Bioglobe offer Enzyme pollution remediation for major oil-spills, oceans and coastal waters, marinas and inland water, sewage and nitrate remediation and also agriculture and brown-field sites, globally.

For further information:
BioGlobe LTD (UK),
22 Highfield Street,
Leicester LE2 1AB
Phone: +44(0) 116 4736303| Email: info@bioglobe.co.uk