Mater-BI appears to show biodegradation in the marine environment

05.12.2017

At the high-level side event “Together against marine litter and micro-plastics” held at the UN Environment Assembly in Nairobi (Kenya), Christophe De Boissoudy, managing director of Novamont France, presented the vision ofNovamont on the solution to the problem of plastic waste in the environment.

Novamont, he said, is working towards a circular economy model by repositioning biobased and biodegradable plastics in the larger context of the need to recover organic waste for its return to soil through compost. The inherent biodegradability of plastics must be related to each specific environment. This is the reason why, in order to avoid misleading communications, it is essential that the term “biodegradable” is associated only with the relevant degradation environment (where) and its related conditions (how much and how long).
According to Mr De Boissoudy, “Before talking about biodegradation in the marine environment, it is important to remember that 80% of the plastics found at sea is of terrestrial origin. Therefore, we need an efficient waste management in the mainland in order to avoid leakage and we have to block litter before it reaches the sea. The marine environment must be protected in the mainland. Waste must be sorted, collected, recycled, biodegraded in the mainland. Thus, paradoxically, compostability and biodegradability in soil is even more important than biodegradability in the sea, for the sake of the marine environment.”
Biodegradable plastics have been widely studied over the last 20 years. Many national and international standards have been adopted to show biodegradability in industrial composting, home composting and soil (e.g. EN 13432, ASTM D6400, ISO 18606, EN 17033). These standards define the ability of plastics to biodegrade totally (how much) under different conditions without adverse effects towards the environment, in industrial composting, home composting, in soil.
When samples of the various types of Mater-Bi bioplastic were exposed to marine sediments, these were observed to undergo biodegradation, which was established in the laboratory by measuring the metabolism of marine microbes fed with the plastic. Biodegradation exceeded 90% (absolute or relative to the reference material) in less than one year. The biodegradation results were verified by Certiquality within the EU pilot programme "Environmental Technology Verification (ETV).
These results, which were obtained under laboratory conditions, have been further confirmed by Nora-Charlotte Pauli, Jana S. Petermann, Christian Lott, Miriam Weber, who wrote, in “ROYAL SOCIETY-OPEN SCIENCE: Macrofouling communities and the degradation of plastic bags in the sea: an in situ experiment”: “Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies”

(http://rsos.royalsocietypublishing.org/content/4/10/170549).