Biodegradable shopping bags are made of polymers that degrade, or decompose, when exposed to air, water or sunlight. There are two main types:
1. The original biodegradable bags, introduced about ten years ago, are made from resins containing polyethylene, starches and heavy metals such as cadmium, lead, and beryllium. They are still on the market today.
2. About five years ago, a second type was invented using starches combined with biodegradable polymers or polylactic acid. Some of these claim to be fully compostable, meaning that they would break down to organic material suitable for plant growth.
We're hoping too that someone will develop a magical plastic shopping bag that doesn't consume vast quantities of natural resources to make, and disappears immediately without a trace. In the meantime, do the right thing and BYOB—bring you own bag!
