"PACKAGING AND THE ENVIRONMENT - IS BIODEGRADABILITY THE ANSWER?"

Biodegradability

It's always the same.

You are at a drinks party and when in answer to the question "And what do you do" you mention the word "packaging", either the eyes glaze over completely or the question comes back "And when is all this rubbish going to be made bio-degradable?"

Biodegradability is seen as the universal panacea to rid us of this terrible packaging waste.

It's interesting to look to see where this waste came from in the first place. Packaging preserves, presents and protects everything that we buy today, no matter what it is and where we buy it. Up to the point of use it is magic but after use, in the twinkling of the eye, it becomes litter!

Litter is not a packaging problem; it's a social problem. If you travel to Germany you will see no litter. This is not particularly the success of the DSD Greendot system but is an inborn characteristic of a nation who like to behave in a proper and orderly fashion and dispose of their waste properly. No amount of legislation about packaging will change people's slovenly habits if they just believe in throwing litter around willy nilly.

But still biodegradability becomes the Holy Grail. Why?

Part of the answer must lie in the desire to hide up the artefacts of your own behaviour. Why are people so paranoid about the contents of their dustbin?

Could it just be that looking at the level of packaging in the dustbin promotes feelings of guilt? "Did I buy all that? I have been very very profligate and bought far too much. It must be the packaging that seduced me. I must get rid of it and ease my guilt complex."

If only it were that simple.

Packaging is a boon and a benefit and a major contributor to every civilised country. Litter is a blight and an inditement on uncivilised countries.

But let us look at this whole question of biodegradability. It is cosy to think that products made of paper and other cellulose products will biodegrade - how many of your friends will have told you that over the same drinks party where we started. Not strictly true if you study the work of Professor Rathje, the self confessed garbologist who spends his time drilling holes in land fill sites in the United States and finding newspapers which are entirely readable after 25 years and carrots which will still snap when bent after the same period buried in highly compressed anaerobic conditions.

So nature hasn't produced a perfect answer yet and if biodegradables are to work properly, they must do so under all conditions and at present this is extremely unlikely.

Biodegradable materials have been produced in a number of ways and by a number of means over many years. The cosy concept that you can take your polythene bag and let it reduce to nothing has been pursued first of all by those who have added starch and merely ended up with a polythene crumb instead of a polythene bag. The polythene didn't actually change. Then there are those who add magic jungle juice to polymers assuring us that "It will all just degenerate into carbon dioxide and water." Apart from the fact that that is rather difficult with PVC because the chlorine is likely to get in the way, it is still more of a marketing pipedream than a reality. Similarly, carbon dioxide is one of the more pernicious greenhouse gases and the generation of more of it is not normally a good idea.

Truly biodegradable products should arguably be made from naturally occurring sustainable products such as corn. These can in fact be made and by suitable treatment, some interesting products can be made. The unfortunate thing is they still need a very sizeable amount of additive normally copolyesters, which are oil based, to actually make them work.

This concept of "making them work" also raises a number of interesting situations. A fly on the wall at one of the ISO (International Standards Organisation), technical committees on biodegradability will witness some very interesting spats between interested parties. The whole question of whether biodegradability shall be measured at room temperature or at elevated temperature, in very wet conditions, in medium conditions or in dry conditions and over one month, three months, six years, infinity, keeps the discussion going for many hours. The truth is that biodegradability whilst desirable is still a very imprecise science.

Now let's look at the products that can be made from biodegradable materials. The first thing about them is that they are more expensive than the wicked synthetic products that they are replacing. This increasing cost can be twice, three times or ten times depending on what you are actually dealing with but under no circumstances are they currently ever equivalent in price.

Then there is the question of their processability. The traditional plastics materials that we know and see every day have been developed over the last fifty to sixty years to a very high level of sophistication and will process with great efficiency and minimum waste on a wide range of very sophisticated processing machines. Biodegradable polymers don't necessarily want to conform. Major changes in processing and machinery are needed and this, of course, entails extra cost, especially as the volumes concerned are relatively small compared to their traditional counterparts.

Then there is the question of whether the physical properties of the ultimate biodegradable product match up to what is expected. There is absolutely no advantage in having a wonderful biodegradable pack which also allows the contents to rot away due to poor water vapour transmission resistance or which shatter or tear because their physical properties are just not up to modern logistical handling.

Finally of course comes the question of disposal. Everybody hopes that biodegradable products will simply vanish into thin air. This actually is not going to happen. The only way of disposing of biodegradable products in an environmental sustainable manner is to make them part of a sophisticated municipal composting arrangement. These are big, ugly, smelly and contribute as much as any incinerator ever did to the NIMBY syndrome. Nobody wants an incinerator - BANANA - build nothing anywhere near anything else - and similarly nobody wants a municipal composting site with its flies and smells anywhere near their backyard.

But what about recycling you say. One of the problems of biodegradables is that they are not compatible with the normal family of plastics products. A small amount of biodegradable polymer in a perfectly well ordered and efficient recycling stream will completely disrupt that recycling stream, poisoning the 90 - 95% of perfectly good products that are already there. So what looks like an efficient route for recycling, say soft drink bottles or polythene bags, has suddenly turned into something that is only suitable for landfill because its chemical properties have been distorted.

The object of this review is not to knock biodegradables. They are becoming more sophisticated every year and their range of applications extends impressively every year but they are not the universal panacea to the problems of packaging waste recovery. Quite the opposite, as can be seen, they can, if improperly disposed of, add to the problem rather than reducing it.

But the sensible use of biodegradables in domestic compost bags, industrial cushioning and, perhaps most importantly, disposable diapers offer a very exciting opportunity to utilise the properties of this unique range of products to the benefit of mankind. Consider that 4% of all municipal landfill is now disposable diapers and these are now cosily wrapped in polythene film to preserve human waste for eternity. The benefits of turning that into a biodegradable package would be so much better than worrying about the wrapper for your chocolate biscuits.

JOHN WEBB-JENKINS
CHIEF EXECUTIVE
THE INSTITUTE OF PACKAGING
7 October 2002

If you wish to contact John Webb-Jenkins about any aspects of this article, please email him on: jwj@iop.co.uk