Oh, I just assumed they were plastic plastic.
Judging by this: http://www.wiggle.co.uk/elite-corsa-team-550ml-water-bottle-2014/
If that's the same bottle you're right, they're biodegradable polythene.
@Fox started
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Oh, I just assumed they were plastic plastic.
Judging by this:
http://www.wiggle.co.uk/elite-corsa-team-550ml-water-bottle-2014/
If that's the same bottle you're right, they're biodegradable polythene.