The most commonly used plastics packaging materials – PE and PP – can fully biodegrade in nature within two years, according to a landmark study.
The research conducted by UK university Imperial College London, the Standard and Industrial Research Institute of Malaysia (SIRIM), and UK scale-up Polymateria, examined the biodegradation of PE and PP samples with incorporated biotransformation masterbatch technology from Polymateria compared with virgin PP samples.
The materials underwent accelerated weathering testing correlated to the real-world outdoor environment, biodegradation testing to measure biodegradability of the material in soil, and ecotoxicity testing.
Samples incorporating biotransformation technology transformed into a bioavailable wax when exposed to the environment with no microplastics, while the virgin samples without the technology persisted as plastics, the study showed.
The findings, published in a special Materials Degradation edition of Nature Portfolio, revealed that the environmentally safe wax was then fully consumed by microbes as measured through biodegradation testing conducted in Malaysia, leaving no traces of the original material behind.
No significant changes in soil microbiota
Additional ‘first-of-its-kind’ metagenomics analysis demonstrated no significant changes in soil microbiota composition.
It showed higher metabolic activity compared with virgin plastics controls, which the researchers suggested highlights the bioavailability of these materials and their ability to be consumed by microbes that naturally occur in the soil.
The enzymes used by microbes to process the wax were the same as the ones used to digest natural oils or butter, in-depth analysis revealed.
“Uncovering pathways through which polyolefin plastics can fully biodegrade is a remarkable discovery,” said Dr Jose Jimenez Zarco, associate professor in Synthetic Biology at Imperial College London, who led the microbial research.
“We now know how plastics materials previously thought to be almost indestructible can safely return to nature. We are excited to be seeing this approach having real-world impact on tackling plastics pollution.”
Biodegradation testing
SIRIM, Malaysia’s governmental testing and certification body, carried out the biodegradation testing.
Polymateria has previously said that its biotransformation technology can be ‘time-controlled’ according to a product’s shelf-life, and given a ‘Recycle By’ date to promote recycling to consumers.
Manufacturers can therefore use it to make totally recyclable and biodegradable products such as cups, bottles, fruit packaging, dairy pots and hot food containers, it added.
“We are proud to have contributed to this cutting-edge research together with Imperial College London and Polymateria,” said Muhammad Zuhayr, senior researcher from SIRIM.
“According to the Malaysia Plastics Sustainability Roadmap (2021-2030), a significant proportion of plastics in Malaysia are not recycled or managed through appropriate end-of-life pathways, contributing to leakage into the environment.
“This highlights the importance of continuing to strengthen waste management systems while expanding the availability of sustainable material solutions.”
‘A major milestone’
Dr Florence Huynh, vice-president of Innovations at Polymateria and a lead author of the study, said: “As a science-led company, this publication marks a major milestone on our mission to tackle plastics pollution.
“It proves that common plastics materials can fully biodegrade in the open terrestrial environment. The research will give policymakers and industry renewed confidence that scalable solutions do exist for the 32 per cent of plastics packaging waste that leaks into the environment each year globally.”
More than 300 brand owners across Asia – from globally recognised names to regional leaders – are said to be rapidly adopting the biotransformation technology as an antidote to the high levels of plastics leakage in the region.
They join established users across stadiums in the UK. The technology is also being rolled out in emerging markets such as Africa.
