The word “biodegradable” is probably one of the easiest green labels to understand, so one may assume it is also the least likely to be subject to false claims. However, the term is still interpreted very loosely and frequently used on products that are toxic, that break down into harmful environmental contaminants, or that can take many decades, even centuries, to decompose. On top of this, if biodegradable product follows the regular waste stream and is sealed away in landfill, it cannot decompose, so what value does a claim like this have? How do we know when the claim is true? How do we identify a truly “biodegradable” product? Let's start by defining the word.
What does “biodegradable” actually mean?
If something is “biodegradable” it should decompose or be broken down rapidly by combination of microbial action, air, and moisture, and also light. The EU is said to describe a biodegradable substance as something that will naturally decompose into mostly water, carbon dioxide and organic matter (or other elements found in nature) within a period of about six months. However, the fact is that there are no legal definitions, explicit understandings or official standards of the term, making it difficult to regulate its use and to verify or refute a claim. Because of this, many items can be seen as 'biodegradable' since they decompose into smaller parts, compounds or elements, but not everything “biodegradable” is good for the environment or its ecosystems.
So, what should be deemed “biodegradable”?
If we take heed of some of these semi-formal explanations, we can begin to decipher what should be classed as 'biodegradable'. Basically, the use of the word should ideally be restricted to products and materials that break down into smaller parts that:
- Can form part of healthy, functioning soil.
- Can already be found naturally in the earth, in environmentally-safe quantities.
- Are non-toxic or harmful to the surrounding ecosystems, plants, animals or humans.
- Are completely reconstituted into the earth within six months to a year.
- Do not contain chemicals to aid decomposition, and that also may have an affect on the product contained or the components of the surrounding system.
- Are free from dangerous and volatile chemicals or substances that can degrade to become harmful.
So, what should I look out for?
Items claiming to be biodegradable should also have an explanation for how these claims are supported, or at the very least, a full list of ingredients so that the consumer can check up on any suspicious ingredient. Apart from this, here are a few lists of the kinds of things that are biodegradable:
- Paper products - Chemical-free office paper, cardboard boxes, wax paper and newspaper.
- Bio-plastics - Many plastic-like resins are made from biodegradable ingredients, including cornstarch, vegetable oil and other types of plant-derived biomass. However, some 'biodegradable' and 'compostable' bioplastics that mimic regular plastic more closely are not necessarily biodegradable
- Food waste - Almost anything, including meat, cooking oil, milk, fruit and vegetables.
- Any garden refuse.
- Material - Clothing and diapers made from natural fibres.
Many of these items, besides being biodegradable, can also be recycled. To avoid future impacts from all of our non-biodegradable waste (or slowly degrading waste) the following items should be used instead of non-biodegradable items:
- Paper and cardboard packaging, instead of plastic packaging.
- Plant-based bio-plastics, instead of regular, oil-based plastics.
- Biodegradable household cleaners containing naturally derived, certified 'organic' and biodegradable ingredients, excluding toxic or environmentally harmful chemicals and anything that may disrupt normal soil function or pose health threats.
- Biodegradable body care products containing naturally derived, certified 'organic' and biodegradable ingredients, excluding toxic or environmentally harmful chemicals and anything that may disrupt normal soil function or pose health threats.
The value of biodegradable liquids (in detergents, soaps and body products) is still incredibly large because they are flushed into sewerage facilities and waterways where they are diluted and can be broken down sufficiently. These liquids may still have hindering effects on ecosystems if present in large quantities; however, they are definitely better than the non-biodegradable equivalents.
What about compost?
The following items biodegrade quickly and can be composted at home in your garden (in a worm farm, for example) or at a local council compost heap. It is important to keep these items out of landfills, because the benefits of their decomposition into usable compost are not experienced in landfills. Also, methane emissions from landfills will be reduced.
- Kitchen waste - Vegetable and fruit peels and skins, off-cuts, leftovers (not meat- based), egg shells, tea bags and bread.
- Garden waste - Branches and leaves.
Biodegradation in landfills
Landfills present a very interesting challenge: 'Environmentally safe', biodegradable products still can't necessarily biodegrade if they are compressed and buried away from moisture, air and light. It doesn't matter how biodegradable something is, or claims to be, if it is designed to follow the conventional waste stream and end up hidden away from the natural elements.
In other words, until all biodegradable products, packaging and produce are diverted from regular landfills and dealt with separately, these types of claims are of little value.
Apart from this, organic materials compacted in landfills decompose anaerobically (in the absence of oxygen), giving off methane gas (a potent greenhouse gas and contributes to global warming) in the process. Methods and technologies for methane capture (for use as an energy source) have advanced over the last several years; however, they are not yet found everywhere.
What about “photodegradable” and “degradable” items?
Photodegradable refers to materials that break down in the presence of sunlight. Some plastics are engineered to become brittle and break into tiny pieces, but this doesn't mean that they are not harming ecosystems, as well as small creatures, who still mistake plastic particles for food and die from lack of nutritional value, choking or from any toxins that may leach from the plastic.
Degradable refers to something that can deteriorate into smaller components or elements in the presence of natural forces (water, light and air). Plastics would therefore be seen to be degradable because they can break up into microscopic pieces, but, this can take hundreds of years, and even longer if locked away in landfills, not exposed to these elements.
Back to biodegrade-school
Something that can be completely recycled in nature or in the ground, and be ready to be reused by other organisms or processes in a period of about six months to a year, can be termed 'biodegradable'. Anything that takes longer to break down is likely to contain synthetically derived or chemical counterparts and is therefore likely to have a longer lasting impact on the environment, and should be termed as 'degradable', or 'photodegradable', depending on the substance. The latter should be avoided where possible.
It is up to the consumer to ask questions and apply pressure to manufacturers and regulating authorities. This is crucial to ensure transparent labelling of our products, so that the use of the term 'biodegradable' only applies to items that we can be sure will not have a detrimental effect on the health of our planet or our families.
Top 5 Tips: Biodegradable buying
- Look for products marked biodegradable, but make sure they are made out of biodegradable material.
- Biodegradable materials should be able to break down entirely in about 6 months. These should include products made out of paper, card, natural plant fibres (cotton clothes) and plant derived bio-plastics.
- Choose liquid cleaning and body products that are free from harmful chemicals and that have all biodegradable ingredients.
- Compost your biodegradable food and garden waste to use as fertiliser in your gardens. Most plant based food waste can also be fed to worms in a worm farm.
- Choose “biodegradable” materials over “photodegradable” and “degradable” materials.