Airborne Microplastics: What Level of Concern Is Warranted?

(SeaPRwire) –   Microplastics appear to be pervasive—present in our oceans, air, drinking water, and even cosmetic items. Evidence of microplastics and the even smaller nanoplastics has been discovered by researchers within the human body.

Scientists now suspect that these airborne microscopic particles may also be playing a role in planetary warming. This raises a critical question: what level of concern is warranted?

What are the sources of airborne microplastics?

Microplastics are tiny fragments—smaller than five millimeters—that result from the breakdown of plastic goods. As plastics degrade, such as during the washing of polyester garments or from tire wear, microscopic plastic particles are released, which are light enough to become airborne.

Once aloft, they can influence the atmosphere in several ways. “Airborne particles can influence atmospheric conditions through two primary mechanisms,” explains Fay Couceiro, a professor of environmental pollution at the University of Portsmouth. “They can either reflect sunlight back into space, which prevents surface heating and has a cooling effect, or they can absorb the sunlight, warming the surrounding air and thereby contributing to planetary heating.”

What is the climate impact of microplastics?

A recent study in Nature Climate Change concluded that, overall, airborne microplastics—especially dark and colored ones—tend to absorb more heat than they reflect, thus adding to global warming. The study’s authors calculate that atmospheric microplastics might contribute to warming at a rate roughly one-sixth that of black carbon, or soot, which comes from burning fossil fuels.

It is evident, however, that their impact is significantly less than that of major greenhouse gases like carbon dioxide or methane. “In reality, they constitute a very minor portion of the pollutants present in our air,” states Ian Mudway, an associate professor of environmental toxicology at Imperial College London’s School of Public Health, who was not affiliated with the Nature study.

Nevertheless, this is not a reason to dismiss the problem completely.

“Should we be concerned? I believe so. Should we panic? Absolutely not,” remarks Couceiro, who was not involved in the new research. “We lack sufficient evidence to justify eliminating all plastic from the planet. However… I do think concern is justified, and we ought to seek ways to minimize our exposure and prevent it from increasing.”

How harmful are microplastics to the human body?

There remains significant uncertainty regarding the effects of microplastics on human health. “It is a lengthy process to isolate the impact of plastic from other factors like obesity, age, or various other lifestyle influences,” Couceiro notes.

The existing knowledge is not encouraging. Laboratory studies on human cells have shown that high microplastic concentrations can lead to outcomes ranging from inflammation to endocrine system interference. In one of Couceiro’s studies on algae, microplastic presence caused significant disruptions to the ecosystem. “We observed stunted growth in the algae, which subsequently affects all creatures that depend on it for food,” she explains. “So there are consequences for their food supply, as well as direct effects. If an animal consumes the plastic, it can cause intestinal blockages, lodge in gills and impede breathing, or leach chemicals that interfere with hormones and cause infertility.”

Mudway argues that a lack of complete understanding about human health impacts should not delay action: “The devastating environmental impact alone should be sufficient motivation for us to act. Yet, we often find ourselves striving to prove it is harmful to human health, as if that were the only justification for addressing the issue.”

How do you get rid of airborne microplastics?

It is not currently feasible to entirely remove microplastics from the air. “Even if plastic production ceased today, environmental accumulation would continue for some time,” says Couceiro.

For those worried about personal exposure, measures can be taken at home. One study demonstrated that high-efficiency HEPA air purifiers can eliminate more than 99% of nanoparticles from indoor air.

Couceiro advises finding ways to decrease plastic use in daily life. “Cutting down on the plastic we have in our homes will lower the quantity we inhale,” she says. “A sensible approach is needed, but the existing evidence of harm warrants concern.”