Major Category:
Compost & Biodegrade
Please help to explain the difference between biodegradable vs. compostable materials. I have read through several definitions but am still not quite clear on it. Both seem to end up with CO2, H2O and biomass, while biodegradable will be degraded by microorganisms. But some compostable material might be involved with microorganisms as well. Is this right?
Please share some examples of materials in these groups. Many thanks!
The definition I was given is that biodegradable usually means that a commercial facility can cause the product in question to breakdown into usable materials. This may mean treatments not available to you at home.
Compostable means that you can take the product and put it in your home compost or garden and expect that it will break down in a reasonable time frame. For instance, Innovia's NatureFlex compostable film should breakdown in your garden in less than 3 weeks.
To expand on Kate's comments, the FTC Green Guide states;
Claims that a product is "degradable," "biodegradable" or "photodegradable" mean that the materials will break down and return to nature within a reasonably short time after customary disposal.
Additionally, the define compostable;
Composting turns degradable materials into useable compost-humus-like material that enriches the soil and returns nutrients to the earth. "Compostable" claims would be appropriate on products or packages that will break down, or become part of usable compost (for example, soil-conditioning material or mulch), in a safe and timely manner in home compost piles. For composting, a "timely manner" is approximately the same time that it takes organic compounds, like leaves, grass, and food stuff, to compost.
Generally speaking, biodegradeable claims are much broader, with less definition. The reality, as I have stated before, is that if any product ends up in a landfill, it will not break down. A compostable product must be put into a compost in order to allow the product to break down accordingly. In a vast majority of cases, this means the consumer will compost at home. Rather few municipalities have the facilities to do so.
Materials such as PLA are often referred to as compostable, yet in order to achieve a recycling effect they have to be processed thorough industrial composters or incinerators.
Biodegradable materials however can be broken down by other living microorganisms in an eco -environment. There a typically two methods of biodegradation -- degraded aerobically with the use of oxygen, and anaerobically, without the use of oxygen. The goal is to produce more products/ materials that can be broken down by the eco-system.
Derek Dlugosh-Ostap
Pack-Smart Inc.
Many thanks to all. Now I have a clearer view of them. But it seems that I have more doubts on the practice. If the final composted components return nutrients to the soil and earth, how about the inks and adhesives that may be within the packaging materials? They could effect the nutrients to the earth and environmental impact at the end. There is very few chances that the packaging would not include those components, unless it is unprinted and unpigmented. In that sense, does it mean that waste management to enhance recycling and using more recyclable materials would be the proper sustainable approach? Then, single recyclable material would be the goal. Then, how about multilayer and laminated film that may obstruct recyclability, if there is no single material to replace it for product protection?
Just wondering regarding the post-consumer recycled materials, will they require a proper packaging waste collection and handling as well? Are there any constraints or requirements on handling this waste? Or even if it might be mixed with other trash, is it still considered OK for recycling for direct food contact packaging?
The standards that apply to compostable plastics packaging (ASTM6400/EN13432) apply to the finished article, not the material it is made from. So that includes inks and pigments, etc, which can also be compostable. The standards set limits on how quickly and how much of the plastics will biodegrade and what on non-compostable content may be left behind. However, these standards cover the sort of industrialised composting facilities that do not exist in many parts of the world, making the claim a bit pointless.
Biodegradable means the material is degraded by microbial action but does not indicate how much is degraded in what time frame and under what conditions. It may be helpful to look at it this way: all compostable plastics are biodegradable but not all biodegradable plastics are compostable.
In any case, you should always ask yourself this question: How will this product be disposed of? Biodegradable should not, in my opinion, be thought of as justification for landfilling but simply another option that can be considered as part of a responsible end-of-life disposal strategy alongside recycling, incineration, etc.
A tricky question, but there's an easy way to view this. Biodegradation means that a material will break down into its component organic parts, usually when exposed to some combination of heat/light, water, air and microbes. Thus, non-organic materials cannot biodegrade.
Composting is simply a process that causes biodegradation. In general, industrial composting requires more heat than what occurs in backyard piles, and certain materials, such as PLA, require industrial composting. What's left after the process is finished is the broken down organic materials, and the materials that won't break down, some of which are organic and some which are inorganic.
100% biodegradable thus means that complete breakdown into basic elements or naturally occurring molecules will occur. On the other hand, the definition of 100% compostable is fuzzy, as it doesn't mean complete breakdown, but merely breakdown to the point allowed by the composting measure in question.
Anyone wish to correct or confirm?
We have had this debate in our company for several years. The most simple way we look at it is, any object is biodegradable, given enough time. And with most modern materials, the biodegradability is the object in question will decay and lose its form, but the basic materials (resins?) will not effectively breakdown. Conversely, compostable products do change their physical and other characteristics back to base organic and inorganic compounds as found in a natural setting.
A couple of resources are The Biodegradable Products Institute, (bpiworld.org) and also the US Composting Council website. In addition, the US Federal Trade Commission, Green Guide (currently being revised) is a good reference source. Recently the US FTC has been fining some very high profile companies on their "biodegradable" claims. You need to really make sure of whatever your verifications studies are before marketing the products these days. The regulators are starting to crack down.
This is obviously wrong because there are petroleum based polymers that can biodegrade
What part of the message string are you referring to as "wrong". And if you know some examples please pass them on.
Huge debate re: "biodegradable" petroleum based products. In reality, they only break down with the addition of additives, and they only break into smaller pieces, not into technical nutrients.
Yes, they only break down with the addition of additives, and they only break into smaller pieces, not into nutrients. Biodegradable means it can be composed and petroleum base products are are those who needs addition of additives. It is discussed several times in this article as well.
The difference between biodegradable products and compostable products is determined by the RATE of biodegradation, disintegration and toxicity. All compostable products are by default biodegradable, but not vice versa.
In the US, ASTM (Association for the Society of Testing) 6400 has a set of standards with regards to compostability for bioplastics.
In short: a product must disintegrate more than 90% of its original content or into pieces less than 2mm within 180 days with no harmful impact on the final compost or the composting process.
In depth:
* Biodegradability is determined by measuring the amount of CO2 produced over a certain time period by the biodegrading plastic. The standards require 60% conversion of carbon into carbon dioxide within 180 days for resins made from single polymer and 90% conversion of carbon into carbon dioxide for co-polymers or polymer mixes.
* Disintegration is measured by sieving the material to determine the biodegraded size and less than 10% should remain on a 2mm screen within 120 days.
* Eco toxicity is measured by having concentrations of heavy metals below the limits set by the standards and by testing plant growth by mixing the compost with soil in different concentrations and comparing it with controlled compost.
By coincidence I stumbled upon a brief titled "Bio-based and Biodegradable Polymers 2008" to be published the winter of 2009. Judging from what I read in the report scope and areas of focus, you might want to keep an eye open for the release of this report. There were a few interesting teasers in the brief that could assist your own information search.
Biodegradation in the environment is NOT the same thing as composting.
Composting is an artificial process operated according to a much shorter timescale than the processes of nature. Standards (such as ASTM D6400, EN13432, ISO 17088 and Australian Standard 4736-06) designed for compostable plastic should not therefore be used for plastic which is designed to self-destruct if it gets into the environment. Indeed EN13432 itself says that is not appropriate for waste which may end up in the environment through uncontrolled means.
The appropriate standard for biodegradation in the environment is ASTM D6954 (see OPA reply to compostable plastics industry at www.biodeg.org [11])
Composting of organic waste makes sense, but compostable plastic for shopping bags, food packaging, etc. does not. It is up to 400% more expensive than ordinary plastic; it is thicker and heavier and requires more trucks to transport it; recycling with oil-based plastics is impossible; it uses scarce land and water resources to produce the raw material, and substantial amounts of non-renewable hydro-carbons are burned and CO2 emitted, by the tractors and other machines employed. If buried in landfill, compostable plastic can emit methane (a greenhouse gas 23 times more powerful than CO2) in anaerobic conditions.
Many industrial composters of organic waste around the world do not want plastic of any kind in their feedstock, because it is difficult to separate biodegradable plastic from ordinary plastic. Home composting of plastic should not be encouraged, as it will often be contaminated with food residues, and temperatures may not rise high enough to kill the pathogens. Compostable plastic is useless in compost because 90% of it has to convert to CO2 gas in order to comply with ASTM D6400 and the other composting Standards. It therefore contributes to greenhouse gases but not to the improvement of the soil.
OPA, you make some very clear arguments here against the use of putting biodegradable/compostable plastics into the marketplace. What, in your opinion, is a solution for plastics that escape formalized collection & treatment processes?
OPA is mixing and mis-leading in his comments. The comment about composting being an articifcial process is totally and undeniably false. Composting is a natural occurance anywhere you have animal and plant organisms and is just part of Nature. It is part of the entire environmental cycle which has been going on since the beginning of time.
ASTM 6954 is a guide for labratory testing of biodegradable plastics and as part of the guidelines the materials have up to 24 months to degrade. ASTM 6400 is for the actual composting and is at a 90 day time limit for the materials to degrade. And his comments about weights, trucking, value of the compost etc., are just unproved assumptions. The same can be said for OXO plastics and probably more so.
OPA is also mis-leading in his points about carbon emissions for growing raw materials, transport etc. Most if not all OXO degradable plastics are hydrocarbon, (petroleum or gas) derived and the carbon emissions of extracting, transport, processing, manufacturing, transport to end user can be and are just as high, if not higher then the bioresins coming on the market now.
It should be noted OPA is an industry association of OXO degradable plastics convertors and manufactuers who have a severe interest in the emerging competition to them of newer and probably more environmentally friendly products coming on line and giving them competition or reduction in sales. In addition, their raw material hydrocarbon sources are finite. There is only so much left, then, once the dinosaur juice runs out,that is it, your done.
In addition as the base raw material becomes scarcer, prices rise dramatically as was seen just about 1.5 years ago. Bioresins remained relatively steady in price through out that period.
Just had the time to view Ian Connacher's award winning documentary titled "Addicted to Plastic" last evening. Its a must see for all debating the differences between biodegradable vs. compostable! The documentary took three years of filming in 12 countries on 5 continents, including two trips to the middle of the Pacific Ocean where plastic debris accumulates. It really offers a holistic view to the effects of plastic on our lifestyles, health and the cost to the environment.
To dig deeper Google the title or rent a copy from your local DVD rental outlet. After viewing "Addicted to Plastic" I believe the discussion here will heat up since no stone has been left unturned and the knowledge base has just been broaden.
If you find Addicted to Plastic and eye opener check out " Food Inc". A revealing documentary on the food industry in the United States, which for those with fickle appetites will want to consider free range & organic raised livestock as an alternative. Why do I mention Food Inc in a plastic blog? Packaging! It all comes back to packaging and the contents of that package. So I ask the question why are we playing Russian Roulette with what sustains our well being, our sources of nourishment?
KJ – for the difference between oxo-bio and compostable (hydro-bio) plastics see http://www.biodeg.org/advantages.htm [12]. For plastic waste which escapes formalized collection we need oxo-bio plastic which self-destructs if it gets into the open environment. It can be re-used many times and if it does get collected during its useful life it can be recycled (www.biodeg.org/recycling.htm [13]). If all plastic had been oxo-biodegradable there would be no North-Pacific garbage patch.
We are talking here about industrial composting, which is an artificially accelerated process, and that is why it needs a 90 day time-limit. This is not necessary for oxobio. Leaves and twigs take 10 years or more to biodegrade, but oxobio will biodegrade much more quickly. It does not just fragment, and it does not contain heavy metals. Compostable plastic is not suitable for home composting.
Compostable plastic will not readily degrade in the environment, so it is not much use if you are concerned about plastic waste in the open environment.
Yes, oil is finite, but oxo-bio is made from a by-product, which used to be wasted, so nobody is importing extra oil to make it.
Weight and space comparisons are not assumptions. It is undeniable that compostable plastics are thicker and heavier for the same strength, unless mixed with oil-based plastic. More trucks on the road and more diesel burned.
A recent study in Germany http://www.kunststoffverpackungen.de/en/news/LCA%20waste%20bags%20-%20St... [14] showed that oil-based plastic has a much better Life-cycle Assessment than compostable plastics.
The “Biodegradable Plastics Institute” and “European Bioplastics” sound independent and official, but they are lobbyists for the compostable plastic manufacturers. The OPA does not deny that it represents the oxo-biodegradable industry, and spends most of its time responding to the increasingly desperate attacks of the compostable industry, who know that their product is hopelessly expensive and impractical. It is not even useful in compost, because ASTM D6400 requires rapid conversion to CO2 gas, so it contributes to climate-change but does not improve the soil.
OPA, I'm not sure what planet you live on but here on earth, leaves only take a few months to biodegrade and small twigs a couple of years.
We produce a consumer product with anapproximate 8 - 12 month life cycle. It is thrown away by consumers when they are finished with it. It would be extramely rare for a consumer to have more than 10 of these items in a year so the volume is extremely small per consumer and the waste product is dirty. Recyclers have no way to pick it up and generally don't want it because it's dirty (not oil, but dirt).
It's made of LDPE film. We now produce it as Oxo-Degradable with an approximate 2 year breakdown time after it it hits the landfill.
So, we have a product that is small volume and not of interest to recyclers and will be thrown in the garbage when it's use ful life is finished. Is it not better to produce it as Oxo-degradable rather than standard film where the breakdown is only two years vs centuries?
Is it not better to have it breakdown rather than place in a home composter where food growing may be the end use of the compost?
I don't really care whether it's "compostable" or "bio-degradable". We just want to reduce landfill volumes and offer an alternative to standard film.
I don't think PLA is our answer due to cost. I also wonder about PLA getting into the recycle stream.
So OPA's last post seems to make sense to me and in fact, is what I was told by our supplier and other sources when we we're doing our research o what to do with our film.
No, I'm not married to Oxo. Some posters here seem married to "their" concept and I'm not convinced the final answers are out there yet. I'm no expert though.
It seems better to me to have a product that safely breaks down than not breakdown, whatever that product is.
I'm interested in comments on the positive uses of Oxo, if indeed there are any here.
Thanks.
We have done a lot of research on the definition of Biodegradable and Compostable products. You can find more info on our website at http://www.ecogreenwares.com/index.html [15].
What is degradable Plastic?
A degradable plastic which undergoes a significant change in its chemical structure under specific environmental conditions
resulting in a loss of some properties. There is no requirement that the plastic has to degrade from the action of "naturally
occurring microorganism" or any of the other criteria required for compostable plastics.
What is Biodegradable Plastic?
A Biodegradable plastic in which the degradation results from the action of naturally occurring microorganisms such as bacteria,
fungi and algae (ASTM D 6400-99)
What is Compostable Plastic?
A plastic that undergoes degradation by biological processes during composting to yield CO2, water, in organic compounds, and
biomass at a rate consistent with other compostable materials and leaves no visible, distinguishable or toxic residue (ASTM D
6400-99)
What causes the process of biodegradation to begin?
A biodegradable product will only biodegrade if it is in an environment which includes moisture, heat, and microorganisms.
Without those three components, there will be no biodegradation.
Oxo degradable bio-plastic is an additive based type of plastic, developed as a solution for the accumulation of plastic waste. It basically does not biodegrade as the product image offers. It simply degrades into relatively smaller flakes of plastic film if the product is a bag or film. The 100% biodegradability offered by oxo degradable plastic is a rate that applies to only the additive, which only the 2% of the composition of the material consists of. It was first introduced into the plastics industry in 80's, but due to the heavy metal presence in the additive resulting from the cobalt and metal salts in the formulation, was not deemed an environmental solution and did not become of wide use. They can not be composted because that process requires oxygen..
Compostable bio-plastic is derived from renewable resources, mainly starch in this case, and they require landfill or a compost facility so as to biodegrade. A recent study shows findings of a 25-year-old but still readable newspapers and 5 year old still recognizable hot dogs in a landfill. Compostable standards require that plastic must be degraded in the same duration as cellulose (paper), and under the light of 25 year old newspaper and hot dogs, that is kind of difficult to mention. Also as every manufacturer, righteously, considers cost in the first place, a material 4 times the price of conventional plastics will not be feasable on terms of commerce.
The standards applied on bio-plastics, are influenced by major manufacturers of these materials, who are surprisingly members in almost every countries' plastic associations, which we might call an easy back stage pass. The association prepares a proposal for laws regarding bio-plastics. These laws or amendments are tailored in accordance with the manufacturer's product, aiming mainly at blocking penetration of new biodegradable technologies' penetration into the markets to keep competition under control.
"Deep Dish" is not correct. Published scientific work over the past 30 years proves that oxo-biodegradable plastic does not just fragment. Fragmentation is just the first (abiotic) stage, but when the additive has reduced the molecular weight the material becomes accessible to micro-organisms and is bioassimilated in the same way as leaves or twigs.
No heavy metals are used in any additives approved by the Oxobiodegradable Plastics Association. Furthermore those additives are independently tested for ecotoxicity and food-contact.
Compostable plastic is not really renewable because huge amounts of hydrocarbons and water are used in the agricultural production processes. In June 2009 Germany’s Institute for Energy and Environmental Research concluded that oil-based plastics, especially if recycled, have a better Life-cycle Analysis than compostable plastics.
"Deep Dish" is however correct about the standards organisations. These are dominated by the big compostable plastic companies, who have consistently blocked any proposal in Europe for standards suitable for oxo-biodegradable plastics. However, there is a suitable standard in the US (ASTM D6954) and the UAE has just created its own standard which will be widely used in the Middle East and Africa.
"Greenwares" are also incorrect. Biodegradable plastic is not limited to plastic which complies with ASTM D6400 (or EN13432). Oxo-degradation is defined by CEN (the European Standards Organisation) in TR15351 as “degradation resulting from oxidative cleavage of macromolecules.” And oxo-biodegradation as “degradation resulting from oxidative and cell-mediated phenomena, either simultaneously or successively.”
The present problem with oxodegradable is that they dont degrade in specific processing conditions which are the ones in the units that are processing waste.
They will degrade anywhere over an unknown interval of time.
OPA seems to never quite fully explain his references. See the following note from the ASTM D6954.
Quote,
NOTE 1 - The intended use of this guide is for comparison and ranking of data to aid in the design and development and the reduction of environmental impacts of polymers that require no more than 24 months to oxidize and biodegrade in the intended use and disposal options and create no harmful or persistent residues under the appropriate disposal conditions (for example, two seasons of crop-growing conditions in soil).
It is cautioned that the results of any laboratory exposure in this guide cannot be directly extrapolated to actual disposal environments; confirmation to real world exposure is ultimately required as with all ASTM International standards.
Unquote.
ASTM 6400 and 6868 do address real world exposure.
In addition, Several renewable materials suppliers have done their cradle to grave or cradle to cradle carbon footprints, with such organizations as the UK based Carbon Trust and finding that the commonly held assertions and assumptions of "huge" amounts of hydrocarbons and other resources in the agricultural portion of the life-cycle are simply not true. The high carbon output is at the actual manufacturing level of the materials into finished goods, and traditional and non-traditional materials are about equal in carbon emissions at this stage of the manufacturing. Just depends on how efficient your manufacturing facility is.
And Tetra Pak just recently announced it was pursuing development of sugar cane based ethanol Polyproprylene resins for its products. Soooo, how does that stack up against the assertion of agricultural carbon costs???
The whole point of laboratory tests is that they simulate conditions in the real world. They are not themselves conducted in the real world, and tests results are only a guide as to how the tested material will actually perform in the real world.
As Buzz says “confirmation to real world exposure is ultimately required as with all ASTM International standards.” ASTM D6400 and 6868 are two of those standards, and neither of them contain any “real-world” testing.
As to hydro-carbon emissions - In June 2009 Germany’s Institute for Energy and Environmental Research concluded that oil-based plastics, especially if recycled, have a better Life-cycle Analysis than compostable plastics.
They added that “The current bags made from bioplastics have less favourable environmental impact profiles than the other materials examined” and that this is due to the process of raw-material production.
For a diagram showing the huge hydro-carbon emissions created in the production of vegetable-based polymers see http://www.biodeg.org/files/uploaded/biodeg/Hydro-biodegradable_Plastic_... [16]
The cultivation, growth, harvesting, transportation and production of sugar-cane based ethanol will also create big hydrocarbon emissions, unless they are still using slaves on the plantations.
OPA, the German study you referred to did not take into full and complete account the carbon emissions for extracting the oil out of the ground to initial processing in the refinery. That changes the entire report findings.
Also, I did not say what you have quoted me saying. That is a direct quote from the ASTM notes regarding the ASTM 6954.
Lastly, your comment about using slaves still on the plantations is rather unprofessional. Get real.
Buzz... Definitively you looks like an interested part and not precisely in the environment !!!
You looks like some owner of a plastic company avoiding to invest some money in avoiding the contamination for the usage of plastic. Or maybe a compostable company?
Please excuse me about my opinion. I ask you for your pardon because thanks to you I interested myself in your arguments and I entered to the site www.biodeg.org and it is clear that some scientific professionals work in oxo-biodegradation.
Reading your and OPA's arguments, OPA expressed their relations with other companies and also with some scientific professional which work in European Universities. What about you? (you are not an interested part. you do not represent a company, isn't it?).
When I noted your rare interest was when I read your worst argument. Your opinion about the German study!.
You are able to indicate to us about what is the mistake of that organization? You mean, every one is wrong if do not use compostage? (I use it at home. But not as a industrialized way. The world need to use all new technologies. The environmental problem is huge. And you avoiding one of so few solutions !)
You must go to Africa or to Calcuta in india. You have to see direct to the eyes to those small boys and girls who lives with less than a dollar at a day. By the contrary, you are fighting for using crops, maize and/or "green raw materials" instead of plastic.
Who cares about usage of energy in composting? (or do you believe that the usage of crops in compostage is free of contamination?). Also, they explained that for manufacturing green plastic you usage energy!! which one? oil? You support the usage of more and more petroleum!!!
Buzz... I read some arguments from Mr. Scott (¿?) and it is so clear to me that the oxo-biodegradation is a solution for citizens. Of course, much better than the industrial compostage solution on favour of a few economic groups.
Ahhh! by the way, leaves from threes are not compostable if I did understand well from the scientific concepts expressed in OPA. Incredible!. and you are agree!!
Curiously you are disagree with Germany organization, OPA organization, NGO organizations, consumers understanding the negative impact of plastic not processed, etc.
Abraham maslow says... "If the only tool you have is a hammer, you tend to see every problem as a nail!"
Anyway. It is just an opinion. My point is I do not understand you.
The plastic is bad but exist.
The by-derivated of the oil is bad.
If you add both of them you achieve oxo-biodegradable which is good ! BUT, you don't want it.
You prefer two bad things instead of one good thing. Hard to understand without an economic interest.
Best wishes.
Sebastian
Hey Sebastian, I don't think it is fair to criticise Buzz for his views on so-called ozo-biodegradable plastics.
There is a lot of controversy in the plastics industry and beyond about these materials and whether they really do biodegrade. The theory is that once the chemical additives have achieved a certain degree of chain scission - aking the polymer mw below 5000 or so - that microbial action will take over and break down the remaining polymer. Some laboratory studies suggest this occurs, but I believe the jury is still out on how quickly this might happen in the real world.
You are right to suggest that the OPA site carries some respected scientific work but at least some of those scientists are paid advisors to oxo-degradable companies (I prefer to use the original term until the biodegradation is proved beyond all doubt). That is not to say their science is bad, only that you need to look closely at what their trials set out to investigate.
If you want to immerse yourself further in the science then also take a look at the work carried out by Dr Jacques Lemaire and Dr Anne-Marie Delort at the Centre National d'Evaluation de Photoprotection and Université Blaise Pascal (Clermont-Ferrand, France). As I understand, their analysis of oxo-degradable films has shown that very little biodegradation within the first two years, although of course degradation does occur.
Oxo-degradable plastics may provide a good waste management solution in some applications, compostable plastics may provide a solution in others. Some plastics applications lend themselves to recycling and some to incineration. There is no single solution to the waste management problem and no single technology that will present the optimum environmental solution in every application.
The challenge - and it is a big one - is to make sure we use the right materials in the right applications. Attempting to stifle reasonable contributions to this debate is, I think, a little short-sighted.
Chris is right, that oxo plastics may provide a good waste management solution in some applications, and compostable plastics in others. The situation where oxo-biodegradables provide the ONLY solution is where the plastic waste has found its way into the environment, and cannot realistically be collected for recycling or composting. Frankly it does not matter if the plastic does not biodegrade, because below 5,000 Daltons the material has descended into tiny pieces, it is no longer a plastic, and it is not toxic. The fact is however that it does biodegrade, and it is time the compostable industry and their friends stopped telling people that it does not.
Prof Lemaire in France has found biodegradation, and so have Prof Jakubowits in Sweden, Prof Chiellini in Italy, Prof. Scott in the UK, and Prof Ojeda in Brazil. Timescale is not important so long as the material biodegrades more quickly than straw and twigs (about 10 yrs) and much more quickly than ordinary plastic (decades). It does not readily biodegrade in a bottle in the lab, because that is not the natural environment for the micro-organisms concerned. They do not work well under those conditions and some of them die.
Compostable plastic is useful only if there is a commercial composting plant nearby which is willing to accept it. Even then, it is difficult to see that the extra costs of up to 400% are justified, and as already pointed out, they are not "renewable" because the production process burns huge amounts of hydrocarbons. The German LCA is correct. The costs of extracting oil are attributed to the manufacture of fuels and lubricants, and the material from which plastic is made is an inevitable by-product, whch used to be wasted.
I agree with OPA's comments about Oil derived Plastics having a better LCA as compared to Bio Plastics. Bio-plastics look 'sustainable and green', but they are actually not, as has been proven by the Germany’s Institute for Energy.
As long as oil and gas are available ( perhaps 40-50 years ?), it makes sense to use the by product to make plastics, instead of burning it off, which would create enormous CO2 emission.
Problem is not with the oil derived plastics, it is with the careless disposal of plastics waste after usage.
Therefore, post consumer disposal of plastics waste needs to be done in a disciplined manner so that maximum plastic is collected in an economical way and recycled, instead of littering our streets or country side or ending up in the land fill.
Usage of Oxo-Biodegradable plastics acts as an insurance; if unintentionally, plastics waste gets littered or ends up in landfill, it would degrade by a two stage process, viz., Oxidative cleavage into smaller molecules and then be bio-assimiliated( bio degradation) by available micro-organisms.The time frame could be two years or four years or little more, depending upon temperature and microbial activity ( but definitely not a few centuries which is the life of normal plastics !)
As far as Bio-plastics are concerned, they would become relevant, when all the oil is finished.
However, Bio-plastics production is defintely going to cause a shortage of agricultural land as well as water for food production and we can imagine food prices shooting up further, as a consequence.
The British government just released a report that oxo is fake. It is from DEFRA, the Dept. of Environmental Affairs. The State of California and a few other states and cities have reached similar conclusions. All non-industry sponsored studies of oxo have concluded that it doesn't biodegrade and is not of any benefit to the environment. The plastic will fall apart after a few years, though.
The Report says on page 2 that it is not UK Government policy, and it does NOT say that oxo is fake.
In fact, the Report confirms that oxo-biodegradable plastics:
• DO DEGRADE ABIOTICALLY IN A NORMAL ENVIRONMENT
• DO DEGRADE ABIOTICALLY UNDER ELEVATED TEMPERATURES FOUND IN LANDFILL
• DO BIODEGRADE (though not fast enough for composting - but they are not designed for composting)
• DO NOT EMIT METHANE EVEN DEEP IN LANDFILL
• CONTAIN NO HEAVY METALS, and ARE SAFE FOR FOOD CONTACT
The report also confirms that:
• PRO-DEGRADANT ADDITIVES ARE NOT HARMFUL AND HAVE NO NEGATIVE ENVIRONMENTAL IMPACT IN THE PRODUCTION AND USE PHASE
• THERE IS NO EVIDENCE OF BIO-ACCUMULATION NOR ANY HARMFUL EFFECT ON THE ENVIRONMENT
• THERE IS NO EVIDENCE OF ACCUMULATION OF POLLUTANTS
• THERE IS NO EVIDENCE THAT DEGRADABLE PLASTICS ENCOURAGE LITTERING
OPA Member-company Symphony UK have published a detailed response to this report and have met with the Environment Minister see http://d2w.net/response.pdf [17]
As a consumer, all I'm trying to figure out is if I should be buying Bio-degradable, Degradable, Compostable, or Bio-degradable/Compostable bags for my trash.
Unfortunatly I live in a condo so I cannot compost on large scale. And sadly, there are some products you cannot get in recycleable containers (i.e. fresh meat, yogurt) But if I can find a trash bag that breaks down in the landfill in anyway, I would feel better.
I had hoped that a discussion like this would have made it simpler to understand, but this just reiterates why consumers are confused. I am happy to see products like Sun Chips use now compostable bags, but have gathered they will do no good in a landfill nor countertop composting.
How in laymans terms is one to determine what is "ok" for a landfill?
Ordinary plastic is OK in a landfill. It does not degrade, but it occupies very little space and does not emit methane.
Compostable plastic is designed for industrial composting, not for landfill nor biodegradation in the environment - so its not much use for you. It cannot be recycled with ordinary plastic and it will emit methane (a serious greenhouse gas) deep in landfill.
The best option is oxo-biodegradable plastic. You would not litter it yourself, but after it has left your Condo it may get deliberately or accidentally into the open environment. If it does, it will take care of itself by self-destructing within a few months leaving no harmful residues, and it won't find its way into the great Pacific Garbage Patch. If if gets collected during its useful life it can be recycled together with ordinary plastics. In landfill it will break down in the presence of oxygen but will not emit methane.
Compostable plastic can be recycled. It is not at the present moment because volumes are too small.
In the UK, only two plastics are presently recycled, HDPE and PET.
PVC and PP, which are the two others commodity plastics (the most important plastic ) are not recycled because it is uneconomic to do so.
OxoPE would be undistinguisable from non-oxo PE, and will create problems to the recycling streams.
I dont think that Symphony has a solution for the problem.
Ricardo
The problem I see is that more and more govt agencies and independent testing, usually university level research, are finding that most OXO claims cannot be substantiated and have not proved true. Plus nothing, absolutely nothing breaks down in a landfill, whether it is a compostable, OXO, or other type of product. Landfills are designed to seal in the waste, keep out moisture, oxygen and microbal action. They are dry "tombs" made not to degrade. If waste starts breaking down in them, the liners keeping all the toxic goo in them, breaks down due to the shrinkage of the volume and you now have a leaking landfill into the neighboring environment.
And OXO was made to break down in sunlight. How can it break down in a dark tomb of a landfill? The poly resins still exist after the OXO binder breaks down, so how is that good with the poly resin being scattered all over the ground?? At least a compostable product, properly composted goes through a metabolic change and actually turns into rich hummus again. And to be certified compostable, the testing involves growing plant seeds from the compost created from the products. I have never seen that done with any OXO product or claim.
As to landfill, there are many different types. Oxo-bio plastic will breakdown if there is any oxygen present, but it is otherwise completely inert. Compostable plastic will emit methane in anaerobic conditions but oxo will not.
Buzz clearly does not understand oxo and should stop adding to the confusion on this blog. He does not know the difference between oxo and photo. Oxo is not dependent on sunlight. Also there is no such thing as an "oxo-binder." d2w additive breaks the molecular chains in the polymer itself and does not leave any "poly resin."
He does not understand compostable plastic either. It does not turn into a rich humus because in order to comply with ASTM D6400 or EN 13432 it has to convert itself into CO2 gas within 180 days. This adds to climate change but does nothing for the soil.
He is also wrong about plants. There are plenty of reports by independent labs showing plant seeds growing in soil containing degraded oxo-bio plastic.
Well it is quite good to know that such type of thing are happening. Anyway
Really nice information, thanks
I’m surprised that there is no discussion about why plastics should be made compostable at all. Where is the life cycle analysis (LCA) and carbon footprint equivalent measurement that compostable plastics would be superior to non-compostable from an environmental and climate point of view?
Why should you make plastics, which can’t be recycled as they are degrading too fast, and what is the actual contribution from a so called compostable plastics if more than 90% is finally CO2 (a biogas).
There is today no standard for running composts, especially industrial composts, there is only a standard (EN13432/ASTM6400) for the product compost to be ready within a certain period of time to be sold to farmers mainly. Due to the non-standard existence the efficiency of the compost will vary extensively and so called compostable plastics will not always fulfill the lab testing requirements when being in real full scale compost.
There are many reports showing that recycling of plastics will be have a much lower impact on environment than composting.
Finally so called compostable plastics are almost all vegetable based competing with the global land area on food production. It must be a priority to produce food instead of plastics made of renewable materials.
It really is beyond belief to imagine a material capable of breaking plastics into pieces in 4 months, and yet not doing harm to the environment especially under the light of the information that it is a rejected technology from the 80's due to heavy metals in its formulation. Besides, it is a solution no greater than paper shredders. The plastic is still there, only unnoticably this time.
The idea is to develop materials that would be recyclable and compostable, and in the cases where recycling is not justified economically, products could be compostable- This may happen in the case of multilayer films. However a group recently suggested that they could recycle economically some multilayer films.
Deep Dish's information on Oxo formulation is either outdated or he is misinformed.
First of all, none of the major brands of Oxo additives such as 'd2w', 'Reverte', 'TDPA' etc contain any heavy metals. They all use metal salts such as Iron, Ni,Co etc which are found as nutrient elements in many of the fruits/vegetables/fish we consume regularly. ( please see http://www.biodeg.org/position-papers/transition-metal-salts/?domain=bio... [18]).
The content of these salts in the Oxo-Biodegradable plastic is really very miniscule, posing no risk, as has been verified in actual usage conditons as well as laboratory testing. This is tested as per protocol given in Tier 3 of ASTM 6954-04 test standard.
Secondly, Oxo-Biodegradable plastics degrade by a two step process. Step one is Oxidative breakdown by chain scission to smaller molecular weight in presence of air,heat and UV/Sunlight.( this happens in litter, soil and in upper layers of landfill ). Step 2 is bio-assimiliation of low molecular weight plastic by micro-organisms present in the disposal environment. The end product is Water, CO2 and humus.
Thirdly, Oxo-Biodegradable plastics can be re-used and recycled, if collected. If they are discarded irresponsibly and do not get a chance to be recycled, they degrade as explained in above paragraphs.
And OXO was made to break down in sunlight. How can it break down in a dark tomb of a landfill? The poly resins still exist after the OXO binder breaks down, so how is that good with the poly resin being scattered all over the ground?? At least a compostable product, properly composted goes through a metabolic change and actually turns into rich hummus again. And to be certified compostable, the testing involves growing plant seeds from the compost created from the products. I have never seen that done with any OXO product or claim.
Shakul defending oxo additive is no surprise as he is a packaging agent in Dubai, where there is a lack of compost facilities, and the majority of the country consists of sand, there is no harm to add some plastic dust to this. Basicly, Saudi Arabia and GCC are already the target markets for D2W and Reverte. The power to penetrate decision making organs, for sure results in approval by environment committees in these countries. Once you have a standard at hand that is tailored for your product, voila! Unless it is organic, there is nothing that those micro organisms can do. Add 1% additive to Polyethylene and it will become biodegradable is hard to believe. This is basic chemistry, not alchemy. Oxo additive is a solution against accumulation of plastic waste, nothing more. It makes plastic tear into small pieces, at a cost of releasing more hazardous components to the nature.
Shakul defending oxo additive is no surprise as he is a packaging agent in Dubai, where there is a lack of compost facilities, and the majority of the country consists of sand, there is no harm to add some plastic dust to this. Basicly, Saudi Arabia and GCC are already the target markets for D2W and Reverte. The power to penetrate decision making organs, for sure results in approval by environment committees in these countries. Once you have a standard at hand that is tailored for your product, voila! Unless it is organic, there is nothing that those micro organisms can do. Add 1% additive to Polyethylene and it will become biodegradable is hard to believe. This is basic chemistry, not alchemy. Oxo additive is a solution against accumulation of plastic waste, nothing more. It makes plastic tear into small pieces, at a cost of releasing more hazardous components to the nature.
Deep Dish - I like to give you a few comments concerning the oxobio technology. The additives have only the purpose to prepare plastics molecules (the disintegration phase) to be digested by microbes if the final material is in such an environment. The issue with oxobio is not if it works or not, there are very many scientific reports and certified tests available to prove this (very many just to find on internet also), the issue is that the suppliers of oxobio do recommend too low concentration of the additives in order to get the business. One issue all suppliers of oxobio are aware of is that a low concentration like around 1% will not guarantee that the additive is homogenous spread in the final product and thus the technology might work or might not work. The technology itself is viable for a product to become biodegradable. I would say that the suppliers are marketing and selling viability, but when it comes to the final delivery and inclusion in the application this might not be viable, because of the low concentration. The only purpose of having a low concentration is to have a low impact on the final cost for the producer. As from a marketing point of view the oxobio market is a mature market with a number of established producers and in a mature market very often the competitive strategy the participants have to get the business is to compete on price primarily. This is exactly the case here. Thus the low inclusion rate and thus the potential viability issue. This is normal for any technology unless someone is breaking the behaviour. So called vegetable based plastics, starch etc, producers will have the same problem in due time when they compete on the market. The major issue in reality is instead that very few producers and also retailers believe that an added value should provide any extra cost to the product. In a mass market like plastics packaging this is the issue.
I'm just a conscientious dog owner who scoops up my dog's poop about 3 times a day . . . I'm not a scientist. And despite having read most of the posts here, I guess I'm looking for some basic answers as to what kind of poop litter bags I should buy.
Should I buy the bags made out of high-density polyethylene foil, reportedly containing the organic raw materials carbon and water, advertised as OXO-BIODEGRADABLE, and costing about 3.7-4.7 cents per bag?
Or should I buy the non-polyethylene bags made out of the raw material MaterBi (known as "BioBag", with a naturally compelling picture of an ear of corn on their packaging), advertised as 100% compostable and biodegradable, which will purportedly decompose within 40 days in a well-functioning composting environment, and costing about 16.4-17 cents per bag?
I'm a city-dweller . . . so honestly, I don't know where my garbage goes, its just taken away, and I'd probably be horrified to see the place it lands . . . so I don't want to see it, but I do care about what I'm contributing to it. Can anyone tell me what's the best poop bags to buy??
Oxo-degradable is an additive that makes plastic break into small parts, it does not biodegrade. Compostables will be a better choice.
Thanks for the guidance!