By Noor Faezah Mohd Sani and Fairus Muhamad Darus

A single plastic bag can take centuries to break down, slowly fragmenting into microplastics that now contaminate every corner of the planet. These tiny particles, measuring less than 5 mm, have been detected in oceans, rivers, soil, drinking water, and even the food we consume. Recent scientific reports have revealed the presence of microplastics in human blood, lungs, breast milk, and placentas, highlighting a concerning intrusion of plastic into our biological systems.

The scale of the problem is immense. Globally, more than 430 million tonnes of plastic are produced each year, with the figure is expected to double by 2050. In Malaysia, an estimated one million tonnes of plastic waste are generated annually, placing the country among the top contributors of mismanaged plastic waste in Southeast Asia. As plastic continues to accumulate, attention is now turning towards a remarkable natural ally: bacteria capable of breaking down plastic.

The persistent challenge of plastic waste

Conventional waste management methods have struggled to keep pace with the escalation of plastic use. Landfilling and incineration only delay the environmental burden, while recycling rates remain low. In Malaysia, the national plastic recycling rate is estimated at around 30 per cent, hampered by contamination and the high cost of sorting multiple types of polymers.

This growing crisis has pushed scientists to explore innovative, sustainable alternatives. One promising avenue is microbial biodegradation, where bacteria produce enzymes capable of breaking down synthetic polymers into simpler, harmless compounds.

Plastic-degrading bacteria: nature’s tiny recyclers

Interest in plastic-degrading bacteria surged in 2016 when Japanese researchers discovered Ideonella sakaiensis, a bacterium capable of digesting polyethylene terephthalate (PET), the plastic commonly used in beverage bottles. Since then, other bacterial genera such as Pseudomonas, Bacillus, and Rhodococcus have shown the ability to break down plastics like polystyrene and polyethylene.

These microorganisms deploy specialised enzymes, such as PETase and MHETase that cleave long plastic polymers into smaller molecules, ultimately converting them into water, carbon dioxide, and biomass.

Developments in Malaysia

Malaysia’s tropical environment and rich microbial diversity make it an ideal landscape for discovering new plastic-degrading bacteria. Research teams across Universiti Malaya (UM), Universiti Kebangsaan Malaysia (UKM) and Universiti Malaysia Terengganu (UMT) have begun isolating local bacterial strains from landfills, mangrove soils and wastewater sites.

Early studies have reported local isolates capable of degrading low-density polyethylene (LDPE) films under laboratory conditions, though the degradation rate remains slow, but these findings signal strong potential for Malaysia to contribute to global biotechnological innovations in plastic waste management.

Opportunities and limitations

Despite its potential, microbial degradation of plastics remains in the early stages of real-world application and is constrained by several key limitations.

First, the degradation process is typically slow, with most bacterial strains requiring weeks or even months to break down plastics, which restricts their feasibility for large-scale waste management.

Second, many bacteria exhibit narrow polymer specificity, meaning they can degrade only one type of plastic, even though actual waste streams contain complex mixtures of polymers.

Third, scaling the technology for industrial use presents significant challenges because producing bacterial enzymes in high volumes, ensuring their stability, and maintaining consistent performance in outdoor or variable environmental conditions involve high costs and technical complexity.

Malaysia’s role in a bio-circular future

Malaysia has outlined commitments through its Roadmap Towards Zero Single-Use Plastics 2018–2030, aiming to curb plastic consumption, strengthen recycling ecosystems, and promote green innovation. Incorporating bacterial biodegradation technologies into this national agenda could accelerate progress towards a more circular, bio-based economy.

Greater investment in research grants, public–private partnerships, and pilot demonstration facilities will be essential for Malaysia to take the lead in Southeast Asian microbial biotechnology.

Conclusion

Microplastics may be microscopic in size, but their environmental and health impacts are vast. As they continue to infiltrate ecosystems and human bodies, the urgency for sustainable solutions grows stronger. Harnessing plastic-eating bacteria offers an inspiring avenue toward reducing plastic pollution as one grounded in scientific innovation and the resilience of natural systems.

While bacterial biodegradation is not a standalone solution, it represents a vital piece of a broader strategy involving reduced plastic use, improved waste management, and stronger environmental policies. With continued research and strategic national support, these “tiny heroes” may one day play a major role in freeing our planet from the mounting burden of plastic pollution.

-- BERNAMA

Noor Faezah Mohd Sani and Fairus Muhamad Darus are lecturers at the Faculty of Applied Sciences, Universiti Teknologi MARA.