UK – biodegradable polymers study indicates their environmental credentials

Over the last decade, the performance and availability of biodegradable polymers (BDPs) has developed strongly, driven by increasing interest in sustainable development, desire to reduce dependence upon finite resources and changing policies and attitudes in waste management. Most of the biodegradable polymers on the market or in development are based on renewable raw material feedstocks from agriculture or forestry.



A new report Biodegradable Polymers and Sustainability: Insights from Life Cycle Assessment has been prepared by Richard Murphy (Imperial College London), and Ian Bartle, on behalf of the UK National Non-Food Crops Centre.



The report reviews current knowledge on the environmental impact of BDPs, primarily from Life Cycle Assessment (LCA) studies but also from a survey of opinion on BDPs among interested parties in the BDP and bio-polymer fields.



Conclusions



The findings are that:

Available LCA results usually show that BDPs have advantages over petro-chemical based polymers in several environmental impact categories including typically fossil energy consumption and global warming potential

BDPs have favourable eco-profiles for many applications due to their relatively low energy in manufacture, CO2 ‘‘neutral‘‘ status for their agriculture/forestry-based organic carbon content, renewability and end-of-life value from compost or energy recovery.

Disposal at end-of-life is a significant phase in the life cycle for capturing environmental benefit from BDPs.

Changes in waste management practices in UK should provide improved disposal options for BDPs

BDPs can offer the potential to add value and environmental benefit through the use of by-products, co-products and wastes from other UK industries.

Further research is needed on emissions (especially of methane) from BDPs in domestic and municipal composting and on modelling of likely future UK waste management practices applicable to BDPs.

Further development is needed to establish an appropriate LCA database on BDPs.

Certified labelling and Environmental Product Declarations (EPDs) to ISO 14025 offer good ways for presenting the environmental credentials of BDPs to consumers and businesses.

Several classes of BDPs made from renewable raw materials (RRMs) have a positive role to play in advancing UK‘‘s move towards greater sustainability by reducing environmental impacts over their life cycles. This role is likely to become more significant in the future. LCAs should be used to verify and update this view for specific cases on an ongoing basis. Advances in BDP manufacturing processes are likely to improve their environmental performance still further compared to conventional plastics, which already benefit from economies of scale