As the U.S. population grows, so does the number of cattle, and that in turn is giving rise to one heck of big, strange waste disposal problem. At least one cattle carcass recycling method that was used in the past is no longer available in this country, so billions of pounds of waste meat and bone have been classified as fit only for disposal, contributing to overburdened landfills. Now a team of scientists at Clemson University have come up with a way to recycle at least part of the mess by converting cattle bone meal into bioplastic.
The Cattle Carcass Conundrum
Until a couple of years ago, cattle carcasses were routinely ground up and used to make food for domesticated animals, including pets. Then Mad Cow Disease happened in the U.K. The lethal disease can be spread by ingesting certain parts of infected cattle. In order to prevent mass infection in the U.S., the Food and Drug Administration classified certain cattle parts and whole carcasses of older cattle as “cattle material prohibited in animal feed.” As cattle herds cycle out of the age limit, the sheer bulk of the problem will diminish, but that still leaves a lot of ongoing waste, in addition to waste spikes that may arise if and when other diseases appear.
Bioplastic from Bone Meal
The Clemson team used a combination of meat and bone meal to engineer a bioplastic, using a process that has the added advantage of deactivating the infectious agent that causes bovine spongiform encephalopathy, aka Mad Cow Disease. They also found that the new bioplastic can be mixed with an ultra-durable form of polyethylene plastic, without significantly weakening the characteristics of the polyethylene. This gives rise to the possibility that one day in the future, high-durability products such as skis and snowboards may be some day include a bit of bone meal.
What Good is a Partly Biodegradable Plastic?
All things being equal, a material that is part bioplastic, part conventional plastic is not a particularly sustainable solution. However, as a transitional material, the new bone meal plastic can at least help reduce the need for petroleum feedstock to manufacture a wide variety of items, including ones that call for durability. Biodegradable car parts are on the rise, for example, not only from vegetable matter but also from at least animal-derived source, chicken feathers.
Image: Cattle skull by Tom Hilton on flickr.com.
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.