Microplastics are also in the sky, according to Japanese scientists

Microplastics may have become an essential component of clouds, contaminating nearly everything we eat and drink via 'plastic rainfall'. Image: Shutterstock

Microplastics are everywhere... even in the clouds! A team of Japanese scientists has taken a close look at this very phenomenon, magnifying the trajectory of airborne microplastics circulating in the atmosphere, in order to assess their negative impact on human health and that of the planet.

Plastic particles smaller than 5 mm, commonly known as microplastics, represent a real scourge for both our health and that of the environment. Scientific literature has shown that microplastics infiltrate animal stomachs and even human blood. Significant quantities also end up in seas and oceans. "Ten million tons of these plastic bits end up in the ocean, released with the ocean spray, and find their way into the atmosphere. This implies that microplastics may have become an essential component of clouds, contaminating nearly everything we eat and drink via 'plastic rainfall'," point out researchers at Waseda University in Tokyo, Japan, who recently studied the presence of microplastics in the atmosphere.

Also read: Plastiglomerate: 'Rocks' made up of plastic waste and coral rubble identified in Indonesia

“While most studies on microplastics have focused on aquatic ecosystems, few have looked into their impact on cloud formation and climate change as 'airborne particles'," outlines a press release on the research. For this study, recently published in the journal Environmental Chemistry Letters, the research team collected "cloud water" from the tops of Mount Oyama and Mount Fuji, located southwest of the city of Tokyo and rising to altitudes of between 1,300 and 3,776 meters. Using advanced imaging techniques, the scientists were able to detect the presence of microplastics in the cloud water, as well as analyze their physical and chemical properties.

"Significant changes in the ecological balance of the planet"

In total, nine types of polymer (plus one type of rubber) were identified as sources of airborne microplastics (AMP). The study also mentions the abundant presence of water-hungry (so-called "hydrophilic") polymers in clouds. According to the authors, these results confirm that airborne microplastics play a key role in the rapid formation of clouds, which could eventually affect the global climate. The accumulation of MPAs in the atmosphere, particularly in polar regions, could lead to significant changes in the planet's ecological balance, including a severe loss of biodiversity.

Also read: The ever-growing problem of plastic pollution in the oceans

"AMPs are degraded much faster in the upper atmosphere than on the ground due to strong ultraviolet radiation, and this degradation releases greenhouse gases and contributes to global warming. As a result, the findings of this study can be used to account for the effects of AMPs in future global warming projections," explains Hiroshi Okochi, professor at Waseda University and lead researcher of the study. "If the issue of 'plastic air pollution' is not addressed proactively, climate change and ecological risks may become a reality, causing irreversible and serious environmental damage in the future," warns the scientist.