A generation after the world successfully tackled the issue of acid rain, new, more insidious pollutants are now falling from the skies — microplastics and forever chemicals. Decades of strict environmental policies have all but eradicated acid rain, but these newer contaminants, such as microplastics and per- and polyfluoroalkyl substances (PFAS), have taken their place, continuing to harm both the environment and human health.

Microplastics, tiny fragments of plastic debris smaller than 5 millimeters, are generated from sources such as synthetic clothing fibers, car tires, and plastic products breaking down over time. These particles can be found everywhere, from urban streets to remote areas far from human activity. Once airborne, they are carried by wind and rain, eventually falling to the ground as part of normal precipitation. While acid rain was largely the result of industrial emissions and sulfur dioxide, the microplastic problem is more pervasive, with particles traveling long distances from their sources.

In addition to microplastics, PFAS — chemicals found in items like nonstick cookware, waterproof clothing, and stain-resistant fabrics — have also made their way into the atmosphere. These chemicals, often referred to as “forever chemicals,” are notorious for their persistence in the environment. Unlike other pollutants that can break down over time, PFAS can remain in soil, water, and even living organisms for decades, if not centuries. As a result, these substances now seep into drinking water sources, leading to widespread contamination.

Water treatment facilities have made significant strides in removing certain pollutants from drinking water, but they are often ineffective at fully addressing microplastics and PFAS. The tiny size of microplastic particles makes them nearly impossible to filter out completely, and while PFAS can be partially removed, they are often still present in trace amounts. This means that even when water passes through treatment plants, many of these pollutants remain, eventually making their way into the tap water that people drink, as well as into food supplies and other parts of the ecosystem.

Health experts have raised growing concerns about the long-term impacts of microplastics and PFAS on human health. Studies have shown that microplastics are now present in human lungs, blood, and even placental tissue, which suggests that these particles are making their way deep into the body. Similarly, PFAS have been linked to serious health issues, including cancer, kidney disease, liver damage, and immune system disorders. The full range of health risks associated with these substances is still unfolding, but experts fear the consequences could be far-reaching.

One of the most alarming aspects of this situation is the fact that, unlike acid rain, which could be mitigated through changes in industrial practices, the cycle of microplastics and PFAS seems unstoppable. As long as plastic products are manufactured and used at current rates, and as long as PFAS remain prevalent in consumer goods, the environmental contamination will persist.

The scale of the problem is global. Microplastics have been found in rainwater around the world, from remote areas of the Arctic to bustling urban centers. In fact, scientists are now detecting microplastics in rain samples collected from locations as diverse as Europe, North America, and Asia. This widespread distribution means that even regions that are far from major sources of pollution are not immune to the effects of microplastic contamination.

The shift from acid rain to microplastics and PFAS as dominant environmental pollutants underscores a fundamental change in the types of challenges humanity faces when it comes to pollution. Acid rain was a problem that could be addressed by cutting emissions from industrial sources. However, microplastics and PFAS are a product of consumer culture, embedded in everyday items that are difficult to regulate or replace.

While solutions are still being explored, addressing these pollutants will require a multi-faceted approach. Reducing plastic production and consumption, advancing more effective filtration technologies, and finding safer alternatives to PFAS are all crucial steps in mitigating the long-term effects of this pollution. Public policy will need to evolve to keep pace with the emerging threats posed by these pollutants, and greater awareness of the issue will be essential to generating public support for necessary changes.

In the meantime, the environmental and health consequences of microplastics and PFAS continue to unfold. As these pollutants become a permanent part of the atmosphere and water systems, there is a growing urgency to understand the full extent of their impact and to develop strategies for dealing with them before it’s too late. In this new age of pollution, humanity is facing a challenge that may be far harder to solve than the acid rain problem that preceded it.