'Weathered' Microplastics Found to be 'More Toxic' to Human Brains, Study Says

A new study highlights the impact of "secondary" microplastics on humans.

According to the researchers, continuous consumption of them might result in the inflammation of the brain-a neurotoxin in the making.

Microplastics Everywhere

There are initial experiments that help scientists discover the potential effect of "weathered" microplastics on humans.

As Science Alert writes in its report, they are considered to be "far more toxic" than fresh ones to the human brain cells. Annually, 8 million metric tons of plastic are thrown everywhere, regardless of whether it's on land, water, or air.

When a plastic-made material disintegrates into smaller components, that's the time when secondary microplastics emerge.

With their minuscule sizes, even the tiniest organisms can swallow them. The plankton, for example, can ingest these dangerous microplastics in the sea.

As scientists continue to study its impact on the environment, they also discover that it can heavily affect the humans at the top of the food chain.

The recent study titled "Microglial phagocytosis of polystyrene microplastics results in immune alteration and apoptosis in vitro and in vivo" is spearheaded by Dr. Jinkyu Park, Professor of Veterinary Medicine at Kyungpook National University, and Director Choi Sungkyun, Head of the Core Protein Resource Center at DGIST.

How Did the Experts Test the Harmfulness of Microplastics?

As mentioned in the report by Medical Express, the team experimented to know how harmful the secondary microplastics are.

In one trial, they emulate how natural weathering works on plastics. What they did was they artificially devised a method to produce "crushed microplastics."

The scientists exposed the specimen to ultraviolet irradiation and physical impact for seven days. This simple simulation will help them see how the plastics interact with everything around it.

Another experiment focuses on determining the detrimental impacts of secondary microplastics. They fed microplastics to lab rats for a week.

According to the findings, the scientists observed a hint of "inflammatory proteins" linked to cell death and neurodegeneration.

The researchers discovered that secondary microplastics can trigger inflammatory responses in the brain via microglia stimulation.

In this case, they also said that secondary microplastics can act as the brain's neurotoxins.

"Through proteomics-based analysis, we have, for the first time, identified that plastic leaked into the environment undergoes an accelerated weathering process, transforming into secondary microplastics that can serve as neurotoxic substances, leading to increased inflammation and cell death in the brain," Director Choi said.

With the uncontrollable spread of plastics in the environment, ingesting a secondary microplastic has been a part of the daily life of humans.

The human brain inflammation is a serious aftermath of this activity. This may be just the tip of the iceberg since scientists might discover more implications of microplastics' harmfulness.

Visit the Environmental Research journal for more information about this study.