Think you’re safe pouring yourself a glass of freshly fallen rainwater? Think again. A recent Swedish study has delivered a global wake-up call: rainwater—yes, even in the world’s most remote places—is now unfit for drinking. The culprits? A class of substances so stubborn they’re nicknamed “forever chemicals.” Let’s dive into the findings, and why your next camping trip might call for bottled water instead of your usual eco-friendly cup held to the sky.
What Are PFAS, and Why Should You Care?
You know how everyone talks about microplastics traveling from the tallest peaks to the deepest oceans? Turns out, they have company—and it’s not the welcome kind. Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have made themselves at home in every corner of the planet. If you think that’s an exaggeration, a study by the University of Stockholm, published on 2 August 2022 in Environmental Science & Technology, confirms these chemicals are everywhere—soils, rivers, oceans, and, now, falling from the sky.
Why are PFAS such a headache? Well, scientists have a nickname for them: « forever chemicals ». True to their name, they’re almost indestructible. Once released, they linger. Thanks to their impressive (and terrifying) resilience, they’ve circulated around the globe, making their way into rainwater and even snow.
Rainwater: Now a Global No-Go for Drinking
The study’s verdict isn’t sugar-coated: rainwater shouldn’t be consumed anywhere on Earth. Regardless of whether you’re in a bustling city or a remote mountain sanctuary, you should think twice—or rather, don’t think at all—about drinking rain that falls from above. Why? PFAS concentrations have simply become too high. And, as researchers note, even if the overall concentrations of PFAS have declined a bit over recent decades, the remaining levels are still too high for certain substances, making the water unsafe.
This contamination problem has far-reaching health implications. PFAS have been linked to a variety of serious health issues. These include:
- Certain types of cancer
- Infertility problems
- Pregnancy complications
- Immune system deficiencies
- High cholesterol (hypercholesterolemia)
- Learning and behavioral issues in children
So, not exactly the ingredient list you want in your drink.
The Persistence and Spread of Forever Chemicals
Curious how PFAS keep escaping cleanup efforts? Scientists didn’t just sit in the lab—they got outside and measured these chemicals in the real world. They discovered that, despite 3M (the main manufacturer) starting to phase out some PFAS, the environmental levels of certain types have hardly budged. No surprise really, since PFAS are champions of persistence.
The study also flagged a specific mechanism responsible for these chemicals’ lasting presence: the ocean-to-air transmission. When ocean water is whipped up into marine spray, PFAS hitch a ride into the atmosphere, and then come back down, courtesy of rain and snow. This endless recycling means PFAS remain locked in a global cycle, which continually surpasses the safety thresholds set by regulators worldwide for human drinking water.
A Difficult Outlook—and a Narrow Margin for Action
If you were hoping for a glimmer of optimism, there’s not much here. The researchers involved in the study are blunt: the room for action is very limited. They suggest that global limits for PFAS concentrations need urgent updating. The catch? Even the current limits have already been exceeded, and it may be too late to simply tweak the numbers.
What does this mean for the future? In short:
- Rainwater, regardless of location, should not be considered potable.
- PFAS continue to circulate in the environment, defying containment and cleanup efforts.
- Health guidelines must catch up to scientific reality—even if staying within set limits is becoming increasingly impossible.
In sum, if you’re traveling, hiking, or just curious about rain-catching for sustainable living, take heed: the era of safe rainwater seems, for now, behind us. Until regulations can catch up or cleanup becomes viable, perhaps best to keep the umbrella close and your water filter closer.
John Smith is a culinary enthusiast and food blogger who discovered his love for Asian cuisine during his years living in Seoul and Tokyo. With a background in journalism, he brings a storytelling approach to exploring the cultural significance behind every dish. John is passionate about making Asian cooking accessible to home cooks and sharing the vibrant food scenes he encounters in his travels.
