How to measure biodegradation

By knowing the exact nature of the material concerned, it is possible to know a priori if it will easily biodegrade or not. 

Starch, cellulose and sugars quickly biodegrade (several days or weeks). (Co)polyesters (PBAT, PBAT-stareh, PHA, PBS, PBSA) biodegrade less easily (several months). However, some materials almost do not biodegrade this is the case for PET, polyolefins (PE, PP) and PVC which take several hundred years to biodegrade. PLA degrades very quickly in compost (several weeks) but a lot longer at room temperature (several years). 

It is useful to know these elements prior to more specific tests. In particular, this allows us to question the validity of a biodegradation test before concluding when the response observed is different to that obtained a priori. 

The principle is simple. The samples tested, previously weighed in their initial state, are exposed to previously established biodegradation conditions (landfill, compost or in natural water bodies, in the open air, etc.). 

The norms NF EN ISO 846 of August 1997 and ISO 15985 of Deceniber 2004 (Appendix B) propose methods to calculate the loss of mass for sampled incubated under aerobic and anaerobic laboratory conditions. 

---