For a long time, plastic pollution has mainly been caused by petroleum-based materials that are difficult to degrade, which break down into harmful microplastics. But now, we may have a feasible alternative.
The latest research by a top government research institution under the Ministry of Chemicals and Fertilizers in India shows that polylactic acid (PLA), a compostable polymer, can safely degrade in the Indian soil environment without leaving persistent microplastic pollution.
This study monitored PLA microplastics in the soil environment for 30, 60, 90, 120 and 180 days. The results showed that the pollution level dropped significantly: the number of particles per kilogram of soil decreased from 287 to only 18 after 180 days, demonstrating that it can nearly completely degrade under natural conditions.
Research indicates that PLA not only degrades over time but also integrates into the soil ecosystem; in contrast, traditional plastics persist for decades and continuously break down into microplastics.
Core research conclusions
Within 180 days, the number of PLA microplastics per kilogram dropped sharply from 287 to 18. During the same period, traditional plastics showed almost no significant degradation. No toxic residues were detected after PLA degradation, and the heavy metal content met international safety standards. Soil organisms, such as earthworms, maintained normal physiological activity when exposed to PLA, which was in stark contrast to their response when exposed to petroleum-based plastics. S K Nayak, the former director-general of the Central Institute of Petrochemical Engineering and Technology (CIPET) in India, stated: "The latest research results clearly reveal the behavioral differences of various materials in the environment. Traditional plastics are difficult to degrade and persist in the soil as microplastics for a long time; in contrast, PLA can rapidly decompose under light and soil conditions and achieve true biodegradation. Scientific analysis and biological tests have confirmed that PLA is basically converted into simple compounds that can be absorbed by organisms within 180 days. This proves that PLA does not cause long-term microplastic pollution and is a scientifically verified sustainable alternative."
Vikram Bhanushali, the president of the Indian Compostable Polymers Association (ICPA), added, "This research is a significant milestone, confirming that PLA and PLA-based materials can effectively biodegrade under Indian environmental conditions without leaving harmful residues. It reinforces the application value of certified compostable materials in areas where biodegradability is needed to prevent the accumulation of non-recyclable plastic waste. PLA materials can safely return to nature, providing a reliable supplement to the existing waste management system. More importantly, this research provides strong scientific support for India to further refine its policy framework, allowing truly biodegradable materials to be formally incorporated into the core strategies of environmental protection, circular economy, and sustainable development. These science-based strategies will improve responsible lifecycle management paths, drive industry investment and innovation, accelerate the development of next-generation eco-friendly packaging materials, and position India at the forefront of scientifically led sustainable material management."
Avantika Saraogi, the executive director of Balasore Sugar Mills Limited, said, "This research is of great significance to the Indian bioplastics industry. Previously, most discussions were based on perception, but now there is scientific evidence that materials like PLA can naturally decompose without causing long-term damage to the environment."
Report summary: PLA has demonstrated outstanding practical biodegradation performance in the natural environment of India (light, soil), and biological tests have further confirmed that it can support the natural processes of soil, while traditional plastics will continuously accumulate and remain for a long time.
