Information Regarding Standards such as ATSM D6400-04

The American Society for Testing and Materials (ASTM) recognized oxo-biodegradation and ASTM D6954-04 is the standard guide developed for Exposing and Testing plastics that Degrade in the Environment by a Combination of Oxidation and Biodegradation.

Unfortunately, however, at the present time there are no standards available for the performance of degradable and biodegradable plastics in other disposal environment other than composting.

Commonly quoted standards for compostable plastics are ASTM D6400-04 and EN 13432 and are related to the performance of plastics in a commercially managed compost environment and are not biodegradation standards. Both standards were developed for hydro-biodegradable polymers (e.g. aliphatic polyesters plus modified starch) where the mechanism inducing biodegradation is based on reaction with water and state that in order for a product to be compostable, the following criteria need to be met:

1. Disintegration, the ability to fragment into non-distinguishable pieces after screening and safely support bio-assimilation and microbial growth;

2. Inherent Biodegradation, conversion of carbon to carbon dioxide to the level of 60% and 90% over a period of 180 days for ASTM D6400 and EN 13432 respectively

3. Safety, that there is no evidence of any eco-toxicity in finished compost and soils can support plant growth; and

4. Toxicity, that heavy metal concentrations are less than 50% regulated values in soil amendments.

Our oxo-biodegradable additives meet the requirements of compostability outlined in these standards, except for the rapid carbon to carbon dioxide conversion rate. Plastics made with our additive degrade and ultimately biodegrade slower than the rate specified in these standards. This does not mean that they will not biodegrade; they just convert the carbon to carbon dioxide in a slightly longer time frame. Many naturally occurring materials, all biodegradable, do not convert in the time frames established by ASTM D 6400-04 and EN 13432. To date, we have been unsuccessful in making the point at these standards organizations that the metrics of these standards are inconsistent with the stated objective - to ensure that plastics entering managed compost facilities biodegrade "at a rate comparable to known compostable materials."

-biodegradable technology is not the ultimate or only solution to problems related to plastic waste in the environment but it is a step in the right direction.

There are several areas where oxo-biodegradable plastics can have a major beneficial impact on the environment:

1 RECYCLING

Oxo-biodegradable plastic can be made from recyclate. Oxo-biodegradable plastics can be recycled with other clean commercial polyolefin wastes, provided that regard is had to the inclusion rate and the level of degradation, and that stabilisers are added where necessary.

2. LITTER

Policymakers need always to consider what happens to waste plastic products which escape collection and end up as litter. Discarded conventional plastics remain in the environment for many decades, and are often impossible or too expensive to collect, so recycling, landfill, composting, and incineration are not options for dealing with them. If collected, oxo-biodegradable plastics can be recycled or incinerated, and if not collected they will degrade and disappear, leaving no harmful residues. Exposure to sunlight accelerates degradation, but the process of oxo-biodegradation, once initiated, continues even in the absence of light, so long as air is present. The plastic will degrade much more quickly in the open than in a building, and in warm weather will disappear more quickly. Of course, if the product has been exposed to air for some time before being discarded it will disappear in an even shorter time thereafter.

3 LANDFILL

While disposal is at the bottom of the waste hierarchy, the least desirable way of dealing with once used resources, it remains the most commonly practiced way in virtually every country in the world, including the most developed ones. Oxo-biodegradable plastics fragment and partially biodegrade to CO2 and water in the surface layers of the landfill, but the residues are completely inert deeper in the landfill in the absence of oxygen. They do not emit methane. Governments are concerned to reduce the amount of waste going to landfill, but oxo-biodegradable plastic waste does not have to be sent to landfill at all. It can be recycled (see above). The aim of the EU Landfill Directive 1999 (as amended 2003) is that: (3) the prevention, recycling and recovery of waste should be encouraged as should the use of recovered materials and energy so as to safeguard natural resources and obviate wasteful use of land; Oxo-biodegradable plastics would help to achieve these objectives because, they can be recycled and they can be incinerated with high energy-recovery. Oxo-biodegradable plastic sheet would also reduce the wasteful use of land in a landfill. At present a six to eight inch layer of earth has to be spread over the waste at the end of each day's work. This is very expensive to do, and it uses up a high proportion of the available space in the landfill pit. Conventional plastic products take up more space in a landfill because they trap air, they do not readily disintegrate, and they inhibit the decomposition of their contents in the landfill. (12) protective measures [should] be taken against any threat to the environment in the short as well as in the long-term perspective, and more especially against the pollution of groundwater by leachate infiltration into the soil. Oxo-biodegradable plastics do not cause leachate infiltration (16) measures should be taken to reduce the production of methane gas from landfills, inter alia, in order to reduce global warming, through the reduction of the landfill of biodegradable waste and the requirements to introduce landfill gas control; Unlike normal organic waste, oxo-biodegradable plastics do not produce methane as they degrade.

4. COMPOSTING

Certain standards exist for plastics to be designated as compostable. Our oxo-biodegradable products do not meet these standards, primarily because they do not biodegrade quickly enough in a compost environment. Nonetheless, operators of a number of managed compost facilities accept plastics using oxo-biodegradable technology as an affordable alternative to generally more expensive technologies that meet the standard requirements. Oxo-biodegradable plastic products, do not biodegrade quickly enough to meet compostable plastics standards, however this can be an advantage as they sequester carbon in the soil and contribute to soil structure and fertility producing high quality compost. The 11th September 2003 Report to the Australian Government by the Nolan-ITU Consultancy concludes that: "oxo-biodegradable plastics based on polyolefins contribute to the amount and nutritive value of the compost because much of the carbon from the plastic is in the form of intermediate oxidation products, humic material and cell biomass. Oxo-biodegradable plastic does not degrade quickly in low temperature "windrow" composting, but it is ideal for "in-vessel" composting at the higher temperatures required by the new EU animal by-products regulations. Indeed it is likely that windrow composting will soon have to be phased out.