Why EN13432 Specifies 90% biodegrdable during 180 days, what aobut the rest 10%?
Biodegradability does not exist as a legal concept when discussing bioplastics. Compostability does, and the European standard EN13432 has certified the compostability of packaging materials in the UK since 2002. This asks for a minimum of 90% biodegradation in composting over a 180-day period.
The blogpublished earlier in the week made the statement that as these only decompose to 90% that residual plastics remain thereafter. This is incorrect. The current best laboratory test considers CO2 evolution in relation to a?known biodegradable material, e.g. cellulose.
Ninety percent is the pass limit in the biodegradation test for two reasons: firstly, since the test uses naturally occurring microbes and materials (compost) there is some variability.
And secondly, not all of the biodegradable plastic will be converted to CO2, because during the metabolism of the substrate (biodegradable plastic), water and biomass are also produced. However, given these other products may be?consumed or used by other means or microbes in the compost, it is not?possible to measure them accurately.
Details can be checked from the URL: https://www.edie.net/blog/Compost-degrade-recycle-the-truth-about-plastic-bags/6098222