The presence of microplastics in clouds poses a significant threat to our food and water supply, according to Japanese scientists. These tiny plastic particles, measuring less than 5mm in size, have been detected in clouds, and scientists believe they may be contributing to climate change.

In a recent study published in the journal Environmental Chemical Letters, scientists found several types of polymers and rubber in cloud water around Mount Fuji, Japan’s largest mountain, and Mount Ōyama.

This discovery adds to the growing body of evidence demonstrating that plastic pollution has infiltrated ecosystems across the globe, from the most remote regions to the most intimate parts of our bodies, including the blood, lungs, and placentas of pregnant women.

What makes this discovery both unusual and concerning is its potential impact on our climate.

Cloud water samples were collected at the summits of Mount Fuji and Mount Ōyama at altitudes ranging from 1,300 to 3,776 meters. Mount Fuji’s summit is located in the free troposphere, while Mount Ōyama peaks in the atmospheric boundary layer, both within the lowest layer of Earth’s atmosphere. Advanced imaging techniques were used to identify the presence of microplastics in these samples.

The results were startling. Researchers found nine different types of polymers and one type of rubber in the airborne microplastics. Clouds contained as many as 14 pieces of plastic per liter of water, ranging in size from 7 to 95 micrometers, slightly wider than the average human hair at 80 micrometers.

Plastics are naturally hydrophobic but become hydrophilic, or water-loving, after prolonged exposure to ultraviolet light. This transformation suggests that these polymers may have acted as “condensation nuclei” for cloud ice and water. Condensation nuclei are crucial particles upon which water vapor condenses in the atmosphere, a process essential for cloud formation.

“Overall, our findings suggest that high-altitude microplastics could influence cloud formation and, in turn, might modify the climate.” Lead author Hiroshi Okochi of Waseda University warns, “Microplastics in the free troposphere are transported and contribute to global pollution.” If we do not proactively address the issue of “plastic air pollution,” the consequences could include climate change and ecological risks that cause irreversible and severe environmental damage in the future.

But how do these microplastics find their way into clouds? They have numerous potential sources, from microbeads in cosmetics to the degradation of larger plastic objects like bags. As the authors noted, “Plastics have become quite popular.” While research has extensively examined the release of these tiny fragments into marine and terrestrial environments, the study of airborne microplastics has been somewhat limited.

There are various ways microplastics could enter the atmosphere, including road dust, landfills, tire wear, and artificial grass. Additionally, the ocean can contribute to the dispersion of microplastics into the atmosphere through sea spray and other aerosolization processes, where particles become light enough to be carried in the air.

In conclusion, the discovery of microplastics in clouds raises significant concerns about their potential impact on our climate and the contamination of our food and water supply. Urgent action is needed to address this emerging environmental threat to prevent irreversible and serious environmental damage in the future.