An important discovery was made by a group of researchers at Stanford in relation to the possibility that microorganisms can help us to dispose of all the plastic we produce and that we pour into the environment. The researchers analyzed the methods that are applied by the so-called flour moths, also called tenebrioni mugnai (Tenebrio molitor), small beetles originally native to Europe but now widespread throughout the world, to eat and ingest plastic.
These insects, when still in larval form, are able to consume various forms of plastic and the scientists behind this study, in an attempt to examine where they end up and how these substances are treated once ingested by these insects, discovered that they can also ingest and metabolize toxic plastics including polystyrene containing common chemical additives, something that surprised the researchers themselves.
The flour worms (larvae of Tenebrio molito) are used as feed for various farm animals, from chickens to fish to shrimp. These animals manage to biodegrade the plastic once it arrives in their bowels and can do so safely, as this latest study shows, since the chemical components found in plastics seem not to accumulate in the body of these insects and generally do not cause damage.
It is also an answer to all those questions that arose in relation to the fact that it could be dangerous to feed farm animals with worms that in turn had eaten toxic plastic. This study seems to show that it could be a safe practice, as Wei-Min Wu, an engineer at Stanford’s Department of Civil and Environmental Engineering at the head of the study, openly states.
To arrive at this conclusion, the researchers have ingested polystyrene containing a flame retardant, called hexabromocyclododecane, or HBCD, a plastic additive that serves to reduce flammability but which is under scrutiny by many governments because of its toxicity. The worms, after consuming this polystyrene, then expelled about half of it in the form of small, partially degraded fragments and another half in the form of carbon dioxide.
They were able to expel 90% of HBCD within 24 hours of consuming the plastic and 100% after 48 hours. As a result of this period of time, worms fed HBCD-laden polystyrene seemed as healthy as other specimens fed a normal diet. Currently, the only obstacle for those who already think they can use these worms to reduce the amount of plastic we put into the environment is that the HBCD expelled from worms through faeces is still a danger and therefore it would somehow biodegrade itself. This means that further solutions would have to be found in the future if such a solution were to be adopted.