CSIRO has developed a biodegradable plastic that’s made from wheat starch. They say:
The wheat starch plastic has similar properties to conventional plastic, but it will break down in the compost heap in 40 to 50 days.
They also claim that it won’t contaminate the food it holds, but I wonder if it is suitable for coeliacs given that wheat starch is known to contain residual gluten ?
(Hat tip to Jeremy for that).