“Biodegradable” Plastics: A Myth of Marketing?

When compared to their petroleum based counterparts, bioplastics can be biodegradable, sustainable, more environmentally friendly (lower greenhouse gas emissions and fossil fuel usage) and/or should be a renewable option to plastic product production. Despite certain limitations, bioplastics remain a front runner as a suitable replacement for petroleum based plastics. This study aimed at investigating the biodegradability of bioplastic vs. petroleum based plastic under various conditions.This experiment focused on bioplastic samples retrieved from a frozen yoghurt shop in Chile and its rate of biodegradability under different conditions by varying the temperature, pH and environment. A comparison was drawn between the bioplastic samples and petroleum based plastic samples with both sets being subjected to the same conditions. The spoons were subjected to three temperatures and seven different media (NaOH, NH3, compost, Air, HCl, CH3CHOOH and pond water) to determine their biodegradability.Subsequent to exposing the available bioplastic to different conditions by varying the temperature, pH and nature of the environment, the bioplastic samples did not biodegrade but gained weight. These results were surprising, and were similar to that of the petroleum based plastics under the same conditions. This similarity could lead one to deduce that bioplastic samples labelled as such may in fact not be made from biological sources.