11. See biodegradation , styrofoam, and Polystyrene # Extruded _ polystyrene _ foam. 12. The article on biodegradation has data on some other plastics, as well. 13. As yet, very little is known about pesticide biodegradation under such conditions. 14. Biodegradation can be accomplished by synthesizing polymers with hydrolytically unstable linkages in the backbone.15. It has a major role in natural biodegradation . 16. TCA was one of the remaining groundwater pollutants for which biodegradation has not been resolved, 17. In the environment, PETN undergoes biodegradation . 18. Biodegradation of PDLA is slower than for PLA due to the higher crystallinity of PDLA.19. In these landfills, there are many microorganisms which speed up the biodegradation of plastics. 20. I made a further edit at polystyrene about biodegradation at another editor's request.