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Greenspeak: what does it mean?
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 (25 Apr 08)
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Green-speak: what does it mean?
Do you sometimes wonder what on earth the terms biodegradable, compostable, degradable, recycled, post-consumer recycled, grey-water friendly and other such terms mean? Or what the actual difference between them is?
It is easy to be confused when they are bandied about without accompanying explanation – but we hope this guide will help you understand them a bit better so you can apply them to your purchasing decisions.
Degradable / Biodegradable / Compostable
'Degradable' is a broad term given to natural and manmade substances that can be broken down by natural processes into smaller parts.
Things can be photodegradable (broken down by ultraviolet light), oxidative (broken down by thermal exposure) or biodegradable (broken down by the action of microorganisms). The term ‘degradable’ in itself does not specify any time frame in which something will break down…for instance, a large tree trunk will biodegrade over the space of many years. A tin can is degradable too; it will break down over a long period of time through oxidation, and weathering. An EPI plastic bag (regular plastic that has been treated to make it degradable), will begin to degrade after about 12-18 months, and the time it takes will depend on how much light and stress (movement) it experiences.
Biodegradable is a term given to material that, as a result the of biological activity of microorganisms (bacteria, fungi and algi), breaks down completely into the raw materials of nature (CO2 , H2O, inorganic compounds and biomass) from which it was made, and disappears into the environment.
Compostable is a term given to biodegradable materials that biodegrade within in a certain time frame under typical composting conditions (which require heat and moisture; and are consistent with the composting conditions required for other known compostable materials like cellulose).
So…when you are choosing what to buy, choose ‘compostable’ (which is therefore also biodegradable) wherever possible, or biodegradable (but not necessarily compostable) as a second choice. And remember that everything is degradable (will fall apart into smaller pieces) eventually, even if it takes a century – this term does not actually tell us much about how long the material will linger in our environment or the effect the resultant ‘smaller pieces’ might have.
Recycled / Post-consumer recycled
Recycled content in paper refers to material that has been reclaimed from the waste steam during the paper manufacturing process. Contrary to what many people think, it is not made from recycled paper waste (such as we put out with our recycling each week), but from paper factory waste (offcuts etc). Therefore, whilst it is a much better choice than non-recycled paper, it still made from tree pulp.
Post-consumer recycled content in paper refers to the portion of the material that is made from material that has been used at least once as a paper product and then recycled. This means that no trees are directly cut down to make this content of the paper, and a second great benefit is that post-consumer recycled content creates demand for waste paper (a large portion of which is still dumped in landfill as supply is larger than demand).
So…when you are choosing which paper to buy, choose the highest post-consumer recycled content you can find, or the highest recycled paper content you can find as a second choice.
Grey-water friendly
One of the best places to find independent information about what products are suitable for grey-water usage is Lanfax Laboratories – who are an independent, commercial and research organisation with special interests in soil, water and wastewater analysis. For full information on grey-water suitable products, have a good look at the Lanfax website where they test a multitude of laundry products on the resulting water quality after a test wash, and then present product results based on consideration of multiple criteria together (the combined results are what tells us whether a particular product is or is not suitable for use in grey-water).
The combined criteria Lanfax test on are:
pH: less than 8 (for liquids) and less than 10 (for powders)
sodium load less than 10gms (liquids) and less than 20gms (powders) per wash
phosphorus load less than 1 gm per wash and
electrical conductivity less than 1 dS/m per wash
If the product tests below these levels on all four criteria, then it is considered the least hazardous to plants and soil microbes. Please note that even if you are not using your laundry water on your garden and it is going into the sewer, the less treatment it needs before being non-hazardous to our waterways the better.
So…when you are choosing a laundry product, don’t just go for one that makes claims to be ‘low-sodium’ or ‘phosphate free’. Check the Lanfax Labs website to see how it rates on meeting ALL FOUR of the above criteria.