bioplastics24.com

Target offers shoppers an unusual message about its gift cards at some stores, advising that they are biodegradable. "Just make sure you spend them first," the displays conclude.

This isn't just a marketing gimmick. Plastics made from corn and other plants are carving a tiny niche from the market for conventional petroleum-based plastics and being touted as green alternatives for everything from bulk food containers to lipstick tubes and clothing fiber — as well as gift cards.