Microplastics Could Be Allies in Monitoring Sewage in Rivers - Scitke

2 42 — Dr. Luke Woodford (left) and Prof. Richard Quilliam, with a basket full o’ caged microbeads
University of Stirling

Although people often associate microplastics with environmental hazards, researchers now propose that these particles can actually serve a useful role by helping detect sewage contamination in waterways.

Turning a Weakness into a Strength

One of the main concerns about microplastic pollution is their tendency to attract and carry harmful bacteria.However, researchers could harness this same trait to passively monitor bacterial contaminants from sewage. Currently, monitoring water quality near wastewater treatment plants typically involves taking water samples at specific times and analyzing them in a lab for bacteria linked to insufficient treatment.

The problem is that sewage discharges aren’t always continuous, meaning the timing of sample collection may miss contamination peaks. To overcome this, Dr. Luke Woodford and his team at the University of Stirling in Scotland tested the use of microplastic beads as passive monitoring tools.

?url=http%3A%2F%2Fnewatlas Brightspot.s3.amazonaws.com%2F98%2F1e%2F301aea2d42dda4f4825ca8ab68e0%2Fmicroplastic Neds 1200x630 — A closer view of the 2-mm polyethylene microbeads utilized in the study
University of Stirling

The researchers filled spherical steel mesh cages with microbeads, placed them inside larger mesh baskets, and submerged them in rivers near sewage outfall pipes.The idea was that any bacteria present in the water would attach to the biofilm that naturally forms on the beads’ surface.

Comparing Different Materials in Real-World Conditions

In the study, the researchers tested 2-mm-wide beads made of three materials—polyethylene, rubber, and cork (used as a natural control material). They placed 200 beads of each type into each cage and positioned the baskets both upstream and downstream of a wastewater treatment plant’s outflow in a Scottish river.

Over the course of 23 days, the researchers regularly collected and analyzed the beads. Just 24 hours after deployment, they found that the beads downstream contained significantly higher concentrations of harmful bacteria such as Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, and Enterococcus. This pattern continued—and even worsened—throughout the test period.

?url=http%3A%2F%2Fnewatlas Brightspot.s3.amazonaws.com%2Faf%2Ffc%2F1c125cfd45a2bea39695ac3eeb93%2F1200x630 Cage — One of the two baskets was placed **upstream** of the plant, to establish what sort of bacteria were already present in the river
University of Stirling

“Further genome sequencing showed that many of these bacteria possess genes that increase their resistance to antibiotics and boost their virulence, heightening the threat to both public and environmental health. As sewage discharges rise in the UK, our system actively monitors the pollutants being released and addresses this public health issue head-on,” says Woodford.”This tool could play a vital role in addressing the problem.

Read the original article on: New Atlas