How does it work?
The patented PDQ-H additive from Willow Ridge Plastics works by bonding to the molecular structure of the plastic as it's being extruded. After a stall period of several months, it begins reacting with UV radiation and atmospheric O2. This oxidation breaks up polymer chains until their dalton number is lower than the atomic mass of water, at which point the chains are short and light enough for bacteria to ingest via osmosis, as well as providing a source of oxygen to encourage biofilm colonization of the surface. Microbial life is evident after 4 months, and degradation typically takes 3-4 years, resulting in only water, CO2, and organic fertilizer (humus)
Laboratory testing is quite expensive at approx $20,000 per month. As the reports show, the plastic is continuing to degrade after the tests have ended. While we would love to run all tests until degradation fully completes, we'd have to dramatically increase our prices to accommodate the dedicated laboratory time and space. While we currently have no plans to run additional lab tests in the immediate future, we are completely open and willing to submit our oxo-biodegradable bags for additional testing should the monetary cost become offset in some way.
| An excellent study with slides under both traditional and electron microscope of the bags covered with bacteria vs unmodified control bags without "biofilm" | |
| Rwanda 2016 Report | 750 day testing of oxo-biodegradable plastic, complete with testing of ecotoxicity vs delicate flora and fauna |
| Ecotoxicity Report | Toxicity of biodegradable bags vs daphina (plankton) fish, plants, algae, and earthworms |
| Barley Report | Growing barley on oxo-biodegraded compost |
| Cress Report | Growing cress on oxo-biodegraded compost |
| Heavy Metal Analysis | Determining levels of Arsenic, Cadmium, Copper, Lead, Molybdenum, Nickel, Selenium, Zinc, Mercury, Anthrax, and Slayer left behind in soil with dissolved oxo-biodegradable plastic. |
| 2002 Evaluation | This is the testing data that got our attention back in 2003. We adopted WRP technology several months after this was published. |
| Advanced Materials Center Report | Degredation vs cellulose control, note that degradation is still occurring at the end of the test. |
| Analytical Services Report AS 20-041 | Molecular mass and carbonyl detection |
| D6950 Standard | Guide for Exposing and Testing Plastics that Degrade in the Environment by a Combination of Oxidation and Biodegradation |
| FDA Compliance | Uncle Sam said we're cool |
| Migration Test | Determining if anything will leech from the plastic onto 3 different food-safe solvents |
| Aqueous Medium | Testing the oxo-degrability of bags in river water with microorganisms |
| Rwanda Soil Toxicity Summary | Separate, detailed analysis of results from the Rwanda report |
| HT-GPC Analysis | Has to do with lowering molecular weight to allow bacterial digestion via osmosis through cell membranes |
| Tier 1 Degredation Study | Short-term degradation study |
| Oxi-Biodegradable Plastics Federation Overview | Statement clarifying language and lab testing standards |
"If oxo-biodegradable plastic is so great, why isn't it used more often?"
That's a great question we should all ask the major plastic manufacturers who pass by this technology, as well as our state and local legislators who continue to dump tax dollars into wasteful and inefficient incineration composters.
As Ray Loflin of Willow Ridge Plastic puts it,
“Oxo-biodegradable plastics are designed to biodegrade in ANY environment. It can’t be guaranteed where a customer will dispose of waste, therefore we have a technology that is an insurance policy on covering any environment it goes to. That includes municipal waste, recycling centers, or even litter (accidental or otherwise).
The important thing to note is that ASTM D6400 and D6868 is an industrial composting standard. That is not a home composting standard because there is no such thing as a home composting standard. Industrial composters are massive composting facilities that exert lots of energy and water to keep the material in ideal conditions for slow incineration, which is what is happening to the material. It should also be noted that D6400 is under critical review at ASTM because it does not meet the needs of industrial composters nation wide, who have begun to turn away ‘industrial compostable’ products. They take up to 180 days to meet the requirements of the standard, which is 90 days longer than most composters want it to last.
On top of that, if a product approved under BPI guide lines, or ASTM D6400 guide lines, and ISN’T disposed of in an industrial composter, then it remains as waste and nothing will change that. Therefore, it’s an effective technology in only very specific conditions.
However, an oxo-biodegradable plastic will both degrade and BIODEGRADE in a home composter, unlike other technologies. Because the technology doesn’t require water and high heat to perform, it means there is lots of flexibility.
Unicorn Bags will have a hard time getting on the BPI list because the Biodegradable Plastics Institute is solely run by PLA, Starch, and composting companies. They do not let technologies like oxo-biodegradables into their ‘club’ since they don’t use one of their technologies. None of our products will pass compostability testing because those tests were designed ONLY for hydro biodegradable resins (PLA, starch, etc). It’s essentially saying you want to judge a motorcycle on safety standards designed for a car. ASTM D6954 is the standard guideline for testing Oxo-biodegradable materials.”
