What are biodegradable and compostable products?
What is the difference between compostable and biodegradable?
Compostable Plastic is plastic which is “capable of undergoing biological decomposition in a compost site as part of an available program, such that the plastic is not visually distinguishable and breaks down to carbon dioxide, water, inorganic compounds, and biomass, at a rate consistent with known compostable materials (e.g. cellulose). and leaves no toxic residue.” American Society for Testing & Materials (ASTM).
In order for a plastic to be called compostable, three (3) criteria must be met:
- Biodegrade – break down into carbon dioxide, water and biomass at the same rate as cellulose (paper).
- Disintegrate – the material is indistinguishable in the compost, that it is not visible and needs to be screened out.
- No Eco-toxicity – the biodegradation does not produce any toxic material and the compost can support plant growth.
Biodegradable Plastic is plastic which will degrade from naturally occurring microorganisms, such as bacteria, fungi etc. over a period of time. Note, that there is no requirement for leaving “no toxic residue”, and as well as no requirement for the time it needs to take to biodegrade.
How long will these products take to break down?
Biocompostable products do not decompose on their own. They must enter the composting process. This entails putting them into the soil with food, yard waste and other organic materials. Once the biocompostable product enters the compost system, it will decompose over a few months.
Decomposition time is dependent on two factors. One factor is the way in which biodegradable products are disposed of. Biodegradables are best disposed of in a commercial composting system, as commerical compost piles contain large amounts of moisture, are kept at a high heat and are aerated frequently. In commercial composting systems bioplastics are expected to degrade within 180 days. Within a home composting system, where high levels of heat are not able to be reached and where aeration depends on how often the owner is willing to turn their pile, bioplastics can take more than 180 days to degrade. Another factor is product thickness. The thicker a product is the longer it will take to degrade. Many commercial facilities grind or cut products such as biodegradable cutlery in smaller pieces to decrease degradation time.
What are corn plastics/ PLA?
PLA is polylactic acid and is made from corn starch. It is a bioplastic that is both compostable & biodegradable.*
How are the PLA products (cutlery, bags, cups etc.) manufactured?
They are made by processes which are similar to how plastic products are made – injection molding, extrusion or thermal formed.
How long will the corn-based cutlery take to decompose or compost?
The PLA (corn derived) cutlery and any other products made from PLA (cups, biobags etc.) take longer to biodegrade and perhaps are best composted in a commercial facility. However, they can be composted at home and may take 180 days or more to biodegrade.
Are PLA products edible?
While our PLA products are generally non-toxic, they are not recommended for human consumption. If accidentally ingested, most small pieces of PLA would pass harmlessly through the gastrointestinal tract and are eliminated in the stool. If pain or discomfort occurs, please consult a doctor.