ISLAMABAD Sept 23 (TNS): Several tons of waste plastics are generated every day, and according to a studypublished in ScienceMag, there has been a mind-numbing 6.3 billion tons of it since humans began producing plastics.
We know that plastic is a major pollutant, tough to break down organically, producing toxic fumes when burnt and often entering the food chain because of its longevity.
With the study projecting that plastic waste is only going to increase in the future, it is imperative to find a way to dispose of these immortal polymers safely.
Over time, there have been many efforts made to get around the problem. People usually resort to burying large amount of plastic in landfills, burning it with piles of garbage or recycling it. However, there has been no way to get rid of plastic waste in a harmless way.
Now a study published by scientists from Pakistan and China from World Agroforestry Centre and Kunming Institute of Botany, China, in journal Environmental Pollution might provide a solution to this nagging problem.
Samples extracted from a rubbish dump outside Islamabad in Pakistan showed a soil fungus feeding on plastic, the study says.
Dr Sehroon Khan, head of the study titled “Biodegradation of Polyester Polyurethane by Aspergillus tubingensis,” said in a release by World Agroforestry, “We wanted to identify solutions which already existed in nature, but finding microorganisms which can do the job isn’t easy.”
However, the team was pleasantly surprised with a sample they had taken from the garbage dump in the Pakistani capital.
The fungus called Aspergillus tubingensis, which lives in soil, was found to also grow on plastic and secrete a enzyme that breaks down the polymer molecules.
The team found that the fungus used the strength of its mycelia – the network of root-like filaments grown by fungi – to help break apart the polymers. Even plastics which would otherwise persist in the environment for years can be broken down by the fungus in weeks, the scientists say.
The fungus was tested with plastic in all three states — solid, liquid and gas and gave effective results.
However, the fungus’ performance is affected by a number of factors including pH levels, temperature and the type of culture medium used. The team thinks that figuring these factors out could be key to large-scale use of the fungus for treating plastic waste.
The study of fungus is still a growing field, and researchers say a number of fungi are yet to be discovered. Understanding fungi and harnessing them could be an organic way out to many of the world’s problems, the team notes.
“Our team’s next goal is to determine the ideal conditions for fungal growth and plastic degradation, looking at factors such as pH levels, temperature and culture mediums,” said Dr Khan. “This could pave the way for using the fungus in waste treatment plants, or even in soils which are already contaminated by plastic waste.”
