Are all single-use plastic bags the same? Do they have the same impact on the environment? Are biodegradable bags better than non-biodegradable? Are paper bags better than biodegradable plastic bags?
First things first; before focusing on the material we have to focus on the product, i.e. the best is to avoid disposable bags whenever possible. Remember: prevention is always the best option! Before the invention of plastic bags this waste stream was absolutely insignificant –composed only of those reusable bags that broke after years of use and could not be mended.
Therefore, the discussion on whether a biodegradable plastic bag is better than a non-biodegradable one is as important as it is secondary. First option is reduce, second option is recycle, third –and a sign of the inneficiency of our society- is disposal. Replacing a single-use plastic bag by a single-use biodegradable plastic-bag is not the solution, although it may help reduce the overall impact and pressures on environment.
Biodegradable vs non-biodegradable
If we have to choose between a single-use plastic bag and a single-use biodegradable plastic bag some studies claim that the bio-degradable plastic bags have a higher environmental impact but they are highly missleading. This is because of weak science; they do not consider the ecotoxicology and eutriphocation aspects of plastic. Moreover there is the problem that in these studies and other Life Cycle Assessments they tend to neglect the benefits of composting (which is the primary route for post-use management of biodegradable bags) by not integrating the positive role on soils.
EU-ban on single-use plastic bags
Some countries in Europe have taken different measures to tackle the burden of single-use plastic bags. It is only recently that Janez Potocnik, EU Commissioner for Environment has announced that the EU will study an EU-ban for single-use plastic bags.
A ban on any single-use plastic bag in the EU is a great idea but it should be handled with care to make sure that the biodegradable bags which will replace the current single-use plastic bags are truly biodegradable -i.e. they do not just "fragment"-. This ban should be accompanied with clear reduction targets in terms of single bag units put on the market.
Therefore, an European ban on plastic bags could work if the rule would concurrently state that by biodegradable bags we understand those that follow the European Norm 13432. This EN 13432 requires biodegradation of 90% of the materials in a lab testing within 180 days (of course, the fate of part of bioplastics is to be turned into compost at a compost site). However, more stringent criteria may be considered to ensure this biodegradability can also happen in home composting (some bioplastics degrade well also in home compost heaps, others more slowly) and marine environment.
Having serious standards of biodegradability is essential to make a difference between biodegradable and non-biodegradable. Indeed some so-called “degradable plastics”which do not comply with EN 13432 (e.g. exo-degradables) just break into tiny pieces the size of plancton that do not decompose and end up in the food chain when they are eaten by fish or other animals . Some others do decompose properly but too slow to be composted with food waste, which makes them end up into rejects at the compost site.
Moreover there are very special cases when a single-use really bio-degradable plastic bag could be justified and , to some extend, also very helpful: i.e. to take out the organic waste separately and ease the separate collection of this waste-stream. If the bag is really biodegradable (for instance 100% corn-starch or potato-peel starch complying with EN13432, or also paper bags) it will not create problems in the composting plant and it will fully decompose in the process. This is being used succesfully by more than 20 million Italian and Spanish citizens, mainly in those municipalities doing door-to-door separate collection collection system, and helps achieving hihest captures, reduced percentatges of organics in residual waste, and subsequent operational optimisation. But this is probably the only exception that justifies single-use bio-degradable plastic bags.
All in all it would be very useful if the European Commission could show more than simpathy for the 3rd International Bag-free day and would produce a clear rule as to how to phase out single-use plastic bags. In order to do so it is necessary to associate the ban to EU-wide prevention targets and when necessary even taxation. The funds collected with a tax on single-use plastic bags could be used to finance alternatives and clean the damage done by plastic bags in land and sea.
For the moment it is a fact that single-use plastic bags are bad for the environment (unless they are really biodegradable and deemed as a tool to optimize separate collection) and the economy and that many European countries started to take measures to reduce its use, it is also a fact that reusable bags look a lot nicer and trendier than single-use plastic bags. The environmental awareness in Europe is starting to get single-use plastic bags out of the way and prepare the path towards a Zero Waste society.
First I want apologize for me poor english. But I think is better to tell my opinion than be quiet. I don´t agree when in the article says there are “special cases when a single-use really bio-degradable plastic bag could be justified” refering “to take out the organic waste separately and ease the separate collection of this waste-stream”. I live in a village in the Basque Country witch does the collecte waste separatelly using door-to-door system. We use a bucket to take out the organic stream. We don’t use any plastic bag to do that. We put directly the organic stream in the bucket. I understand that people who has not the experience of doing it so, they may think it is a dirty way to do that. But if you clean the bucket with a kitchen paper after you have use the bucket and you left that paper at the bottom of the bucket, the bucket remains clean and dry and there is not any stench. That is because if there is not humidity in the bucket and so there will not a rotten organic sustances there. Allowing to use plastic bags, even allowing only bio-degradable bags, causes problems on the quality of the compost, because it is easy to people to use non bio-degradable plastic bags in order of the bio-degradable ones. The purity of the compost falls down because of the non biodegradable-plastic. Also it goes against the principle of prevention that is posible to apply in this case without any problem.
BalasHapus[...] Gai honi buruz gehiago Zero Waste Europen [...]
BalasHapus[...] Gai honi buruz gehiago Zero Waste Europen [...]
BalasHapusI completely agree Mikel. There are good examples of how separate collection of organics can take place without bags and I hope all of Europe could follow the example of municipalities like yours. The problem is how to make a ban on single-use plastic bags feasible without letting the non-compostable oxo-degradable plastics take over the market.
BalasHapusAs the article says the priority is to prevent single-use bags -be it compostable or not compostable- and what you say is a perfect example of how this can be done. When prevention is not possible -and we know this is not a technical problem but a political one- it is better to have proper compostable bags than oxo-degradable plastics and non degradable plastics. Prevention would be better but at least, if we all bags are properly compostable, we minimise the environmental impact.
Single use bags should have the health warnings on similar to cigarette packets - that may start making people think.
BalasHapusSupporting the Bag Tax but adding Common Sense - http://www.caseforcompostables.com
BalasHapusA plastic bag levy is to be supported, even a small financial charge has been proven to reduce bag usage by around 80%. We should all suppoprt that. However that still leaves 20% of petro-chemical bags eventually going into landfill.
With a levy setting a 5p benchmark, exempting EN13432 materials means retailers could offer compostable bags at the checkout - these can then be reused in kitchen caddies for household food waste that goes for composting. Doing this means that the bags end up in compost, councils won't be paying for expensive landfill costs/fines and councils can benefit from increased composting material entering their system.
Most organic waste in the UK is collected on a 2 week cycle, unfortunately a simple bucket type solution won't work. The large brown/green bins stink and attract flies, thoroughly unhygienic - an EN13432 compostable bin liner or the use of a kitchen caddy with EN13432 bags solves that.
Please note that whilst 'plastic bags' in the wild are absolutely undesirable, they only comprise 0.03% of UK litter. Why target bags instead of the huge litter types of chewing gum and cigarette butts? The answer is easy - retailers are a fish in a barrel & everyone needs a bag occasionally - low hanging fruit for a revenue-oriented legislation which seriously skews the purpose of the Climate Change act 2008 under which it is enacted.
Under the Climate Change Act 2008 EN13432 Compostable options should be exempted from bag levies and treated as a way of addressing the 20% of bags to be subject to the pre-litter fine. The exemption of compostable alternatives will allows retailer to take plastic 100% out of their stores and participate as more than tax collectors.
The NI Legislation is in consultation Until 9 July 2012, we encourage citizens, business and industry to support the exemption of compostable bags. Thank you
Paul Marshall