Here is some background to it,
http://www.unlockdemocracy.org.uk/wp-content/uploads/2007/01/broadsheet.pdf
Richmond-upon-Thames is getting greener...are you?
The main alternatives proposed are to use cornstarch instead of plastic, and paper bags.
http://news.bbc.co.uk/1/hi
"As though the paper-or-plastic question weren't vexing enough, now some retailers are finding that the "biodegradable" plastic bags they'd hoped would please green shoppers might not be so Earth-friendly after all.
"Lunds and Byerly's recently replaced its plastic bags with a biodegradable bag made of low-density polyethylene that purportedly breaks down when exposed to sunlight, oxygen, soil, moisture and microbes.
"But biodegradable bags are still petroleum-based, and while they do break down into smaller particles, chemicals eventually show up in the food chain and our bodies, according to Susan Hubbard, CEO of Eureka Recycling in Minneapolis. And it's unclear whether biodegradable bags can be recycled."
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