plastic causes pollution; it clutters rivers and seas, chokes wildlife as well
as humans entering into food chain and make our environment a much less
attractive place. Biodegradable plastics that are capable of being decomposed
by living organisms have recently emerged as a solution to the waste
disposal problem. But is it really good for the environment?
Michigan State University (MSU) claim that biodegradable plastics do not break
down any faster than their conventional counterparts. The study published in
the American Chemical Society's journal,†Environmental Science & Technology,
states that several additives that claim to decompose polyethylene (plastic
bags) and polyethylene terephthalate (soda bottles) simply don't work in common
disposal methods such as landfills or composting.
The results are
the culmination of a three-year-long research that focused on five additives.
The study covered the majority of biodegradation methods available on the
market today. The team studied three categories of biodegradation, aerobic
biodegradation experiments, the breakdown of
organic contaminants by microorganisms when oxygen is present, anaerobic
biodegradation, the breakdown in the absence of oxygen, and simply burying
"The claim is
that, with the additives, the plastics will break down to a level in which
microorganisms can use the decomposed material as food. That simply did not
happen. There was no difference between the plastics mixed with the additives
we tested and the ones without," said Rafael Auras, co-author and MSU packaging
highlighted the statement of William Rathje, an Arizona paleontologist and
founder of the archaeological and sociological
study, Tucson Garbage Project, that even after years underground,
chicken bones still had meat on them and even carrots still retain their orange
Susan Selke, co-author of the
study and MSU packaging professor says, "Since
organic materials take so long to decompose, it's not a shocking result that
plastics with some additives would take decades to break down. So, if the
additives don't work, the only solution is to not make claims that are untrue.
And for now, that means not using any of the disposal methods or additives
included in the study as feasible options."
In a growing
trend, many countries have banned or imposed tax for the retail use of plastic
bags, one of the largest sources of polyethylene waste. "For this reason,
plastic manufacturers are also seeking solutions to this problem," Selke
explained. "The study is funded by package-user companies. This is because they
also want to know if the additives that are being marketed to them work. They
want scientific evidence to examine the products and disposal approaches that
are available to them to break down plastic."
Researchers conclude that findings have
wide-ranging implications for consumers, the environment and the companies that
make these biodegradable products. The study is funded by Center for Packaging
Innovation and Sustainability at†MSU.