BIO-DEGRADABLE PLASTICS

There is a new product group on the market known as biodegradable plastics. They are now becoming more popular for shopping bags, disposable plates and cutlery and garden matting. However the environmental benefits of this product type can be varied depending on some important manufacturing and raw material characteristics.

While it is difficult to provide clear evidence that biopolymer plastics are more environmentally preferable than fossil-fuel plastics, they are a positive trend likely to deliver this benefit as the industry matures and the technology improves.

Biodegradable materials can be compared environmentally on the following production and material characteristics:

(1) Does the biopolymer product actually degrade in the environment under natural conditions? Some products entering the market fail in this regard. You can get assurance that the product degrades in the environmental through labelling or information stating that the product has met the requirements of the Good Environmental Choice Label, OK Compost Label from Europe or other international standards specifically measuring degradability.

(2) Seek from the manufacturer a declaration that the corn or potato starch used in the product does not come from genetically modified organisms (GE) and has not been grown in newly established agricultural lands which may have displaced native vegetation, thereby affecting biodiversity. 

(3) Finally, some biopolymer products have high levels of additives which are hazardous materials deposited in the environment as the product degrades. Biodegradable products manufactured to mimic conventional plastics using additives such as  cobalt stearate, manganese stearate and ethylene glycol are particularly harmful as they can disperse catalytic metals into the environment, and are made using non-renewable resources.

(4) You should look for biopolymer products which have a high percentage of starch content. Many biodegradable plastics have very low levels of starch content, containing instead degradable plastics which only break down to dust sized particles, and do not degrade further. These particles remain as pollutants in the environment, affecting the natural systems that micro-organisms depend upon.

For more specific information on these products use the Good Environmental Choice Standard for Compostable Biopolymers in Australia. This standard is used to assess the environmental performance of biopolymer plastic products in Australia and determine if they deserve the Australian 'Good Environmental Choice' Label.

GECA 12-2005 - COMPOSTABLE BIOPOLYMERS

GOOD ENVIRONMENTAL CHOICES

• Use Hessian bags, not plastic, paper or biodegradable plastic bags.

• Look for the Good Environmental Choice Label on bags you need to purchase.

• Dispose of Biodegradable pages in your compost bin, do not put in the recycling bin, as bags require air and moisture for degrading.