The accumulation of plastic litter in ecosystems is a well-known issue. Microplastics are typically the plastic particles that enter natural ecosystems from various sources, including cosmetics, clothing, and industrial processes.
They are less than five-millimetres in length. The fine plastic particles are not just harmful to the aquatic and terrestrial ecosystems, but can also become 'hubs' for antibiotic-resistant bacteria, once they are cleared out from household drains and enter sewage treatment plants, a new study has found.
According to the New Jersey Institute of Technology (NJIT) study, in the US, the ultra-fine plastics particles form a slimy layer (biofilm) on the surface, further allow bacteria and antibiotic waste to combine and secret glue-like substances.
The study noted that some bacterial strains had raised antibiotic resistance by up to 30 times when living on the slimy layers that form inside these treatment plants, India Today reported.
Impact of Microplastics In Treatment Plants
The study's co-author, Mengyan Li, said that these treatment plants could become hotspots, where multiple chemicals, antibiotic-resistant bacteria and pathogens combine. This further poses a risk to aquatic life and human health if they bypass the treatment process.
The scientists assessed several sludge samples from domestic sewage treatment plants for the study and injected them with two commercial microplastics - polyethene and polystyrene.
They found eight different species growing on the microplastics. "We might think of microplastics as tiny beads, but they provide an enormous surface area for microbes to reside," Li added.
Impact on Health
Of the eight species that scientists found in microplastics, they found two emerging human pathogens linked with a respiratory infection.
"As other bacteria attach to the surface and grow, they can even swap DNA with each other. This is how the antibiotic resistance genes are being spread among the community," Li said.
Further studies are required to understand the impact of microplastics bypassing water treatment processes.