Quick Reckoner
Biodegradable, Compostable, Degradable - What is the difference?

Now that there is growing disapproval of polythene plastic bags and what harm they can cause the environment, manufacturers have started to offer ‘greener’ forms of plastic to ease these concerns. More and more businesses, small shopkeepers and supermarkets alike are now stocking more types of these alternatives - especially bags which state they are ‘100% degradable’.

But in addition to this, companies have started to use the words above in different ways, some of which are not necessary correct. Now these words have begun to take on different meanings in the public sphere, which in turn confuses traders and the public.

Remember - the best bag for your shopping is a strong, reusable bag. This is because taking a disposable, single use bag when not needed is unsustainable and a waste of precious resources. However, in today’s society, businesses are expected to provide some kind of cost-effective bag for customers to take home their goods. 

BiodegradableBiodegradable plastic will break down mainly due to naturally occurring micro-organisms or bacterial activity.  Biodegradability is a term which has been known loosely used to describe two main types of plastic bag alternatives; oxo-biodegradable bags (degradable bags) and hydro-biodegradable bags (compostable bags). However, there is a great difference between plastics which are compostable and those which are degradable.

Compostable plastic is simply a biodegradable plastic which has met a certain criteria of compostabilty. This set of criteria includes rate biodegradation, maximum residue of material left at a specific point in time and a requirement for the material to have no harmful impact on the final compost or the composting process. All compostable plastics are biodegradable and can be certified by American and European standards. The most common certificate for compostable bags is the European standard EN-13432. These bags can be placed in your home composting system and should take up to 3-6 months based on favourable conditions.

Degradable plastic is not compostable because it breaks down through chemical or physical impact. These bags are typically regular polythene bags but have added artificial additives to aid their degradation or fragmentation, when exposed to a certain amount of sunlight. These bags are increasingly popular in supermarkets. They degrade much quicker than regular polythene bags - some bags suggesting they start to degrade in 18 months when exposed to significant amount of sunlight. Degradable plastics however break down too slowly to be considered as biodegradable.

Questions and Answers! 

Q - Will compostable bags affect the quality of my home composting system and how good do the conditions have to be for them to break down?
A - Although these bags do break down much quicker than degradable bags, they only break down quickly in really favourable composting conditions e.g. right temperature.  Compostable bags should not affect the quality of your home composting system too much but do not overload it with too many bags. This can lead to making your compost very slimy.

Q - What if compostable bags are not composted? What happens to them?
A - Compostable bags are biodegradable so if they enter the natural environment they will cause less harm than regular polythene bags. However, they present a whole new set of problems if they enter two likely destinations - landfill or recycling bins.

Compostable bags can take longer to degrade in landfill sites and can emit methane, a dangerous greenhouse gas, during degradation. In addition, if compostable bags are mistaken to be regular plastic bags and are placed in recycling bins at supermarkets they can contaminate and ruin the entire batch of plastic recycling. As a result of the recycling process, all that recyclable plastic mixed with compostable material would have to be placed in landfill as waste. An easy mistake to make with costly environmental consequences attached to it.

Q - So are compostable plastic bags a bad idea?A - In essence, we could be creating another problem in trying to solve another.  By implementing these bags on a greater scale we could be creating greater future problems for recycling and greenhouse gas emissions. However, if the public are informed about the correct procedures for disposal of these bags it could save countless lives of marine animals which die from ingested plastic and significantly reduce the horrible effect of oil-based plastic in our environment.

Q - Some plastic bags say that they are proud to be ‘100% degradable’ bags. Is this good for the environment compared to regular polythene?A - The creation of these bags can be seen as a slight improvement, but more of a sideward step if anything at all. Degradable bags will still float about on our streets, rivers, trees and beaches; they will just disappear in a shorter space of time. Even then they will break up into smaller pieces of plastic, only to contaminate the soil with oil-based toxic residues.

However - according to research conducted with these manufacturers, these bags are actually better for the environment. Some degradable bag producers claim that their bags are neutral once degraded, leaving no harmful residue or remnants. In addition, degradable bags can also be recycled with regular polythene.

Q - That all sounds very confusing. So which one is best?A - Sadly there is no disposable bag which can be truly regarded as the greenest. There is certainly a need for greater research in both types of oxo-biodegradable bags and hydro-biodegradable bags. One thing for sure is that a reusable bag, which is preferably biodegradable, should be used to limit disposable bag use in the first place. 

  1. MYTH: San Francisco banned plastic bags and so should our city.
    REALITY: San Francisco is the only significant jurisdiction in the nation that currently bans plastic bags and that law has caused a shift back to paper bags. Switching back to paper bags increases greenhouse gas emissions, energy use and waste.1 As other major cities like New York and Chicago investigate the plastic bag issue, they have chosen plastic bag recycling for their communities. Communities wishing to emulate San Francisco should also understand that San Francisco is one of a handful of communities in the country that has collection of compostable materials including biodegradable plastic bags which was a stated intent of the San Francisco legislation.
  2. MYTH: Our city would be saving so much oil by banning plastic bags.
    REALITY: In the United States, nearly 80% of the raw material used to make plastic bags is produced from North American natural gas, not oil.2 This includes feedstock, process and transportation energy. Much of the energy used to make plastic bags is embodied in the bag itself, and since plastic bags are fully recyclable, that energy is available for new products. Alternatives also use twice as much energy to make – thus banning plastic bags would increase overall energy use and perhaps oil use.
  3. MYTH: Our city would be solving its litter problem by banning plastic bags.REALITY: In effect, banning recyclable plastic bags will not significantly reduce litter or the amount of waste in our sewers and landfills. Litter problems must be addressed directly by targeting littering and providing recycling and waste bins. Banning a certain product will only cause a switch from one form of litter to another. There is no such thing as environmentally preferable litter. Such approaches merely create new problems.
  4. MYTH: Many other cities are banning plastics bags because that is now the trend.REALITY: Nationwide, the prevailing legislative trend is overwhelmingly toward plastic bag recycling. From coast to coast – Los Angeles to New York and now Chicago – cities are moving forward to promote plastic bag recycling. San Francisco remains the only city in the nation that currently enforces a ban on plastic bags.

    Plastic grocery bags are fully recyclable and the number of recycling programs is increasing daily. In 2006, plastic bag recycling increased 24% nationwide to 812 million pounds. There is a growing realization that plastic is a valuable resource.3 Plastic bags can be made into dozens of useful new products, such as building and construction products, low-maintenance fencing and decking, and of course, new bags. There is high demand for this material, and in most areas, demand exceeds the available supply because many consumers are not aware that collection programs are available at local stores.

    In recent years, many grocers and retailers have introduced plastic bag collection programs. Consumers should look for a collection bin, usually located at the front of the store. The number of municipal drop-off centers and curbside programs to recycle plastic bags is increasing also.

Quality Policy

Lotus is an ISO 9001:2000 certified Company. We follow good manufacturing practices that assure consistent high quality results. We have instituted state-of-the-art facilities to monitor and maintain strict quality of our products, processes, and services.