'Biodegradable' plastic bags may not be as eco-friendly as thought

Run_to_da_hills

I always had my suspicions on these products when they break down after a number of years, the chemicals have to go somewhere. I presume this also applies to bio degradable skip bags that would normally end up rotting away on some county council land fill.



http://www.telegraph.co.uk/earth/earthnews/7422006/Biodegradable-plastic-bags-may-not-be-as-eco-friendly-as-thought.html

Macha

Yes, they could actually be considered worse as the plastic breaks down into smaller pieces that are ingested or taken in by animals further down the food chain.

Plant-based bio-degradable materials are much better.

Cunsiderthis

Run_to_da_hills wrote: »

I always had my suspicions on these products when they break down after a number of years, the chemicals have to go somewhere. I presume this also applies to bio degradable skip bags that would normally end up rotting away on some county council land fill.



http://www.telegraph.co.uk/earth/earthnews/7422006/Biodegradable-plastic-bags-may-not-be-as-eco-friendly-as-thought.html

Of course everything is, ultimately, bio degradable. Even nuclear isotopes!

Really, bio degradable plastic always sounded like a contradiction in terms, and we all have to try to apply common sense and intelligence to what we are told and not just accept any claims made by anyone just because they sound nice.

Terms used are always interesting to speculate about and to claim that anything is bio degradable is true. It's just how long it takes to bio degrade and what happens while its bio degrading which is more important. Motor cars are fully bio degradable, and so is plutonium, if we give them long enough.

We all know that "Irish chicken" might have been hatched, grown to maturity and slaughtered in Brazil or China, "Irish smoked salmon" might have been just smoked, or partially smoked, in Ireland and might be from Norway or elsewhere, and there wil always be those who use language to make us believe one thing when, in fact, they want to disguise something else.

Thus "recycling" is now used to cover all sorts of means of disposal, even that bete noire of the green industry, landfill. So when we think we have "recycled" something, we feel all warm and wonderful, and don't question too deeply where its actually gone to!

djpbarry

Cunsiderthis wrote: »

Of course everything is, ultimately, bio degradable. Even nuclear isotopes!

I think you’re conflating biodegradation with radioactive decay.

Cunsiderthis wrote: »

Really, bio degradable plastic always sounded like a contradiction in terms...

Why?

Cunsiderthis wrote: »

Terms used are always interesting to speculate about and to claim that anything is bio degradable is true.

No it is not; there are legal restrictions on the use of the term. For example, in California, it is illegal for companies to claim that their products are biodegradable without proper scientific certification.

Cunsiderthis wrote: »

Thus "recycling" is now used to cover all sorts of means of disposal, even that bete noire of the green industry, landfill.

Ignoring the fact that this statement is not relevant to this thread, you’ve already been warned about making such unsupported claims. You will not be warned again.

Cunsiderthis

Run_to_da_hills wrote: »

I always had my suspicions on these products when they break down after a number of years, the chemicals have to go somewhere. I presume this also applies to bio degradable skip bags that would normally end up rotting away on some county council land fill.



http://www.telegraph.co.uk/earth/earthnews/7422006/Biodegradable-plastic-bags-may-not-be-as-eco-friendly-as-thought.html

The Impacts of Degradable Plastic Bags in Australia
ExcelPlas Australia, Centre for Design at RMIT, Nolan-ITU
Department of the Environment and Heritage, April 2004 , makes the valuable point that so called biodegradable plastics do not break down in landfill any faster than no biodegradable plastics, mainly due to the conditions in landfill not being conducive to allowing materials to break down in dry anaerobic conditions. Alternatively if they do break down they may contribute to the generation of methane, which is a potent greenhouse gas. Life-cycle assessments undertaken for the report The Impact of Degradable Plastic Bags showed that reusable bags have a lower environmental impact than either conventional or degradable single-use bags, suggesting that biodegradable plastic bags lead to consumers using them in the belief that they are “better”, whereas they are, in practice, similar to conventional plastic bags if put into landfill. The impact of degradable plastic bags on recycling programs for conventional plastics still requires further research. All sorts of biodegradable materials, including food and paper, have been found 'mummified' and preserved in such conditions. Even if the biodegradable materials do degrade, the low oxygen levels mean that they can release methane as they break down - a potent greenhouse gas.

Generally it is feared that contamination of recycling processes with degradable plastics may interfere with the recycling processes and undermine the durability of the recycled plastics products produced.