One of the most important things to understand when reviewing the Sustainable concepts of biodegradability and compostability is the definitions of both.
Biodegradation: Biodegradation is the chemical breakdown of materials in the following environments:
- Aerobic Environment (with oxygen) i.e. compost facility
- Anaerobic Environment (without oxygen) i.e. landfill
Biodegradation can be measured in several ways. Aerobic degradation can be measured by the amount of oxygen consumed in the process or the amount of carbon dioxide produced. Anaerobic degradation can be measured by the amount of methane produced from the process. In either case, plastics that are tested to be biodegradable, ideally degrade into more basic elements that some might view as organic matter or earth type material.
There are several often used ASTM standards and test methods used to determine the biodegradability of plastics.
- ASTM D5511-02: Standard Test Method for Determining Anaerobic Biodegradation of Plastic Materials Under High-Solids Anaerobic-Digestion Conditions.
- ASTM D6400-04: Standard Specification for Compostable Plastics.
Why is this important for you? Users of reclosable zipper bag packaging want to be able to purchase a bag that is easily biodegradable. ASTM D5511-02 tests plastics to determine if they will biodegrade in an anerobic environment (no oxygen) similar to a landfill environment. Landfill environments are common in the US. ASTM D6400-04 tests plastics to determine if they will biodegrade in an aerobic environment (oxygen present) similar to a composting environment. Composting environments and facilities are much much less common than landfills in the US.
Minigrips NEWGreenLine Biodegradable Reclosable Zipper Bags are ASTM D5511-02 tested to biodegradable. Find out more by clicking on the GreenLine link.