A study by University of Pittsburgh researchers found that bioplastics are not necessarily greener than petroleum-based plastic when the use of pesticides and synthetic fertilizers are factored in. When the extensive land needed to produce the feedstock to make the bioplastics is also considered, petroleum-based plastics comes out ahead in the study. However, bioplastics beat out petroleum-based plastics when it comes to biodegradability, low toxicity, and the use of renewable resources.
The study looked at 12 plastics, seven petroleum-based, four biopolymers, and one hybrid, and performed a life-cycle assessment (LCA) on each plastic’s production stage. Researchers considered biodegradability, energy efficiency, wastefulness, and toxicity.
Eco Geek points out that since the study is based on current production methods, “improved production practices could improve their relative ranking,” and urges that the study results “should not necessarily be used to bash bioplastics or to make the contrarian argument that petroleum ought to continue to be used.”
Eco Geek suggests that producers of petroleum-based plastics and bioplastics “could work with this study to identify the most damaging aspects of their methods in order to reduce their environmental impacts.”
Perhaps researchers are currently developing a bioplastic that is greener than the current crop. The Japanese electronics manufacturer, NEC Corporation, announced it developed bioplastic from non-edible plant resources last August. The main ingredients of the bioplastic are cellulose, the main compound in plant stems, and cardanol, an oil-like material from cashew nutshells and a byproduct of cashew nut processing. In other words, the bioplastic is made from agricultural waste. NEC will continue to develop the bioplastic with goal of using it in electronic devices by the end of 2013.
Dr. Richard Gross, professor of chemical and biological science at Polytechnic Institute of New York University (NYU-Poly) created a way to produce bioplastic from yeast and the fatty acids of plant oils. Gross’ production method does not use fossil fuels to process the yeast, and the bioplastic produced is resistant to moisture, unlike starch-based bioplastics.
The U.S. Defense Advanced Research Projects Agency (DARPA) had Gross’ company SyntheZyme develop the bioplastic from yeast. DARPA intends to use the bioplastic as packaging material in its solid state, and as biodiesel for military engines after it is broken back down.
“This is a very exciting development in the field, and not just because we’ve created a bioplastic with desirable properties,” said Gross. “This process uses no fossil fuels, and every step is biologically-friendly, from fatty acids in plant oils through the end product, which is a versatile, 100 percent biodegradable plastic.