Microplastics Detected In Clouds Above Japanese Mountains.

By Caroline Ameh

Microplastics have been identified within clouds hovering over two iconic Japanese mountains, Mount Fuji and Mount Oyama. This revelation adds a concerning dimension to the pervasive issue of microplastic pollution, underscoring its ability to traverse long distances and infiltrate ecosystems through “plastic rainfall.”

Researchers have uncovered significant concentrations of these minuscule plastic particles within the cloud samples collected during their study, raising concerns about their potential role in cloud formation and greenhouse gas emissions. Hiroshi Okochi, the lead author of the study and a professor at Waseda University, emphasized the urgency of addressing “plastic air pollution” to prevent adverse climate change and ecological consequences.

Published in Environmental Chemistry Letters, this peer-reviewed paper is believed to be the first to examine clouds for the presence of microplastics.

These microplastics consist of plastic fragments smaller than five millimeters, originating from the degradation of larger plastic items, intentional use in certain products, and industrial effluent discharge. Notably, tires and plastic beads found in personal care products are among the primary sources. Recent research suggests that as much as 10 million tons of microplastics end up in the oceans annually.

The potential health hazards associated with microplastics are a growing concern. Humans and animals inadvertently consume or inhale substantial quantities of these particles, which have been detected in various human organs, including the lungs, brains, hearts, blood, placentas, and feces.

While the full extent of their toxicity is still under investigation, studies on mice exposed to microplastics have indicated behavioral changes, while other research has linked them to conditions like cancer and irritable bowel syndrome.

Researchers from Waseda University collected samples at altitudes ranging from 1,300 to 3,776 meters, revealing the presence of nine types of polymers, such as polyurethane, and one type of rubber within the cloud mist.

The concentration of microplastics in the clouds ranged from 6.7 to 13.9 pieces, including a significant amount of “water-loving” plastic particles. This suggests that microplastic pollution might play a pivotal role in expediting cloud formation, potentially influencing the overall climate.

The rapid degradation of microplastics exposed to ultraviolet light in the upper atmosphere also poses a concern, as they release greenhouse gases during this process. If high concentrations of microplastics were to accumulate in clouds, especially in sensitive polar regions, they could disrupt ecological equilibrium.

Previous studies have detected microplastics in rain, and the authors of this study suggest that the primary sources of airborne plastics may include sea spray or aerosols generated by crashing waves and bursting ocean bubbles, as well as dust from road traffic.