Microplastics from take away food are worsening antibiotic resistance crisis says study

The styrofoam container that you gladly use to take out food is contributing to rising antibiotic resistance. Antibiotic resistance develops when microorganisms like bacteria and fungi develop the potential to overthrow the drugs that are meant to kill them. The recent research carried out by Rice University scientists has shown that styrofoam supports antibiotic resistance in bacteria and provides a suitable environment for their further growth.

Styrofoam is a special type of styrene polymer used for making food containers. When it is discarded, it’s broken down into microplastics (small plastic pieces in the environment resulting from the degradation of consumer products) that provide a comfortable environment not only for the microbes and chemical impurities but in addition to the free-floating genetic supplies that transfer the ability of resistance to the microbes, researchers say.

A paper published in the Journal of Hazardous Materials shows how the ultraviolet growing aged microplastics in the environment make them competent platforms for antibiotic-resistant genes (ARGs).

Antibiotic-resistant genes (genes resisting the effects of antibiotics) are armored by phages (viruses that infect bacteria), bacterial chromosomes (DNA molecules in bacteria), plasmids (small, extrachromosomal DNA in a cell physically separated from chromosomal DNA and can replicate independently) and all organic vectors (a vector is a DNA molecule that is used as a transporter to carry foreign genetic material artificially to another cell where it can be expressed or replicated) that may cause antibiotic resistance in human cells and decrease their ability to fight infections.

The study led by Pedro Alvarez in collaboration with scientists at the University of Houston also showed chemicals leaching from the polystyrene (plastic) as it ages amplify the susceptibility of vectors to horizontal gene transfer (the process of the movement of genetic materials between multicellular and unicellular organisms other than by the vertical transmission of DNA from parents to offsprings through reproduction), through which antibiotic resistance spreads.

“We were surprised to know that microplastic aging increases horizontal ARG”, said Alvarez, Professor of Environmental and Civil Engineering and director of Rice-based Nanotechnology Enabled Water Treatment Centre. “Enhanced dissemination of antibiotic resistance is an overlooked potential impact of microplastics pollution”.

The researchers have found that microplastics with a diameter ranging between 100 nanometers to 5 micrometers are prone to aging by the ultraviolet radiation of the sun and develop high surface areas to trap microbes. As plastics decompose, they also leach depolymerization chemicals that break the microbes’ membranes, providing ARGs with a chance to invade.

They noticed that microplastic surfaces may serve as accumulation sites for susceptible bacteria, speeding gene transfer by getting the bacteria into contact with the chemical released and with each other.

Plastic is one of the defining materials of the modern world. Scientists are trying to know the effects of microplastics on human health and the environment. According to the study, the synergy between bacteria and chemicals could improve the environmental conditions beneficial to antibiotic resistance even in the absence of antibiotics. This shows that arresting plastic pollution is important to combat antibiotic resistance as well.