The situation of rainwater today differs significantly from that of 20, 50, or 100 years ago. In the past, communities relied on rainwater for daily consumption. Rain was akin to a natural filter, where water initially contaminated on the Earth's surface would become clean through evaporation and rainfall.
As a result, people would collect rainwater for consumption. They also faced rain with ease, knowing it wouldn't cause harm, especially since rainwater was still clean and uncontaminated by harmful substances.
However, the present scenario is vastly different. Rainwater now contains vehicle and factory emissions, and even plastic. How did this come to be?
This isn't mere speculation—it's a stark reality. In 2019, National Geographic released a report titled "Microplastics Are Raining Down From the Sky." The report revealed that in the Southern French Pyrenees, there were 365 microplastic particles per square kilometer with every rainfall. This number increases with the intensity of rainfall.
If one assumes this phenomenon is isolated to distant locations and doesn't affect Indonesia, they're entirely mistaken. This could very well occur within our borders too. In January 2022, researchers from Bogor Agricultural Institute published a study titled "The Deposition of Atmospheric Microplastic in Jakarta, Indonesia: The Coastal Urban Area" in the Marine Pollution Bulletin journal.
The study found microplastic content in every raindrop that fell in Jakarta, with particles detected ranging from 500 to 1000 micrometers. According to research by Xao Zhi Lim titled "Microplastics Are Everywhere—But Are They Harmful?" (Nature, 2021), laboratory tests revealed that microplastics can cause immunological disturbances in animals. Fortunately, thus far, no harmful effects of microplastics on humans have been found.
However, a study titled "A rapid review and meta-regression analyses of the toxicological impacts of microplastic exposure in human cells" (April 2022) presented a different perspective. When microplastics are absorbed by the body, reactions occur that result in cell damage and allergic reactions.
Nevertheless, there's a glimmer of hope. Currently, there are no large-scale epidemiological studies on the exposure to microplastics and their health impacts.
The Origin of the Plastic Rain Phenomenon
In geography, there's a natural cycle known as the "water cycle." In essence, water on Earth evaporates under the sun's rays, forming clusters of clouds, and eventually raining down.
This cycle is inevitable—a natural phenomenon. The issue arises because the water in today's era is inundated with plastic waste.
Plastic waste blankets the surface of oceans, rivers, and drains. Citing The Washington Post, Indonesia itself contributed the most to the presence of plastic waste in the ocean in 2021, with 8 million tons of plastic floating in the ocean annually.
As a material that's difficult to degrade, plastic will continue to exist in water. However, it doesn't always remain intact. Some break down into small pieces. These fragments are then called microplastics, which are invisible to the naked eye but present in the water.
The problem escalates when these microplastics transform into tiny particles called nanoplastics. During the water cycle, these plastics join the atmosphere and descend as rain in various locations.
This ongoing phenomenon poses a significant threat to living beings. The plastic adheres to humans, plants, and animals, eventually being absorbed. Thus, humans indirectly consume the plastic absorbed in the bodies of animals and plants. When this occurs, living beings themselves suffer the consequences.
The water cycle cannot be avoided. Therefore, the only solution is to reduce the use of plastic waste, although this is undeniably challenging.