Plastic Bags - COAG Standing Council on Environment and Water

Update on Degradable <strong>Plastic</strong> Standards
The term degradable encompasses several types of the plastics, including biodegradable and oxodegradable
resin. Degradable plastic bags may prove to be a viable substitute for HDPE plastic bags.
However to do so, manufacturers must be able to demonstrate that their products are environmentally
acceptable, with any claims and labeling backed up by sound science. Such products will need to meet
the Australian Standards for degradable plastics currently being developed by Standards Australia.
To date, Standards Australia has finalised a suite of standards to cover the breakdown of biodegradable
plastic under commercial composting conditions:
• AS 14852-2005 - <strong>Plastic</strong> materials - Determination of the ultimate aerobic biodegradability in an
aqueous medium - Method by analysis of evolved carbon dioxide
• AS 14855-2005 - <strong>Plastic</strong> materials - Determination of the ultimate aerobic biodegradability and
disintegration under controlled composting conditions - Method by analysis of evolved carbon dioxide
• AS 4736-2006 - Biodegradable plastics - biodegradable plastics suitable for composting and other
microbial treatment compostability
These are available for purchase from Standards Australia http://www.standards.com.au/
Before the full suite of standards can be developed for a range of other end environments (soil or in
water etc), significant information gaps need to be filled, particularly for materials based on
prodegradant technologies. These include how quickly and under what environmental conditions they
breakdown; the potential human and environmental toxicity of the prodegradant additives; the nature
of any residues left behind after they have been degraded; and the impact they may have on bag
recycling.
It is important to note that the three standards mentioned above relate to degradability in commercial
compost. <strong>Plastic</strong> bags, as shown in Figure 2 on page 27, find their way into a range of different
environments where conditions are significantly different from the controlled conditions of a
commercial operation. Standards development work has recently been undertaken in Europe and
North America on plastic degradability in home composting, soil, fresh water, marine water and other
materials incorporated within a degradable product. These standards will be examined by the
Australian Standards Technical Committee for possible adaptation and adoption as Australian
Standards.
Complementary to the standards work, the <strong>Plastic</strong>s and Chemicals Industries Association, with support
from the Australian Government, is developing a voluntary product stewardship Commitment and
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The definition presented in this consultation RIS, focuses on the purpose for which the bag will be
used rather than the weight, dimensions, style or chemical composition of the bag. A definition
based on these physical attributes could enable plastic bag providers to avoid complying with any
potential voluntary or regulatory action by using plastic bags that fall just outside the designated
range. For example if a definition targeted plastic bags that weigh 6g and under, plastic bag
providers could avoid compliance by using plastic bags that weigh 6.1g. A definition based on
physical characteristics is more prone to ‘loop holes’, which could compromise any action to
reduce plastic bag litter in a nationally consistent approach.
Also on the matter of weight, research undertaken by the Royal Melbourne Institute of Technology
shows that the thickness and weight of a plastic bag does not impact on the ease with which it may
Consultation Regulatory Impact Statement: Investigation of options to reduce the environmental impact of plastic bags January 2007 14