Many of us were urged by our parents not to drink rainwater during our formative years. Now science is backing up the claim that it’s unsafe, with recent research finding toxic, man-made substances in rainwater across the globe. These ‘forever chemicals’ contribute to negative health outcomes with harmful levels detected in regions as remote as Antarctica.

We’ve all done it at one point. You’re outside, thirsty and it starts raining. What’s the harm in taking a swig of the water falling from the heavens – after all, it’s natural, right? You may have even been told that sipping on rainwater wasn’t the healthiest option, though this might have seemed like an overly cautious statement at the time. Only now it isn’t.

Chemicals That Last Forever

PFAS (per- and polyfluoroalkyl substances), also known as ‘Forever Chemicals’, are the collective name for man-made substances that, as the name implies, are extremely persistent elements that are difficult to break down. Originally engineered to increase the utility of household goods, their water and oil repelling properties were highly valued and used in multiple industries including consumer appliances, electronics, aerospace and military applications. Ever used a non-stick frying pan, such as those marketed as containing a ‘Teflon’? Those coatings contain PFAS.

So, what does this have to do with the toxicity of rainwater? Well, the persistent nature of PFAS means that they are turning up in places that were never intended. And there is cause for alarm, as the health impacts of PFAS have been public knowledge for some time (after litigation forced the makers to compensate for adverse public health effects). They include the following:

  • Changes to your immune system
  • Thyroid problems
  • A higher chance of kidney, prostate, or testicular cancer
  • Increased cholesterol levels
  • Higher blood pressure during pregnancy
  • Developmental effects or delays in children

PFAS are everywhere. It’s likely that you already have a low-level circulating in your system.

It would be a fair assumption to believe that simply throwing out all non-stick and water-proof items from your home would place you at a reduced risk for PFAS exposure. Only thing is, PFAS are everywhere. They can be found in paints, personal care products, fast food packaging, clothing and even home cleaning products. Many countries are outlawing their use, enacting bans and forcing industries to switch to safer alternatives. Unfortunately, it’s likely that you already have a low-level of PFAS circulating in your system. The higher the accumulated concentration in your body, the more likely you are to have adverse health effects. As these chemicals degrade slowly, unable to be diluted by water or eaten by bacteria, they tend to move easily through the environment, impacting human resources and naturally occurring ecosystems. PFAS can be found in soil, sediment and waste. They travel through surface water runoff from industrial sites, spreading into stormwater systems and back into our oceans and reservoirs, polluting drinking water and marine life alike. And now they have been found in rainwater.

What The Research Says

The decade-long investigation found that not only is rainwater now generally unsafe for human consumption, but that dangerously high PFAS levels have been detected in Antarctica and the Tibetan plateau.

A new study by scientists at the university of Stockholm has made evermore clear that no corner of the planet is untouched by the issue of PFAS. The decade-long investigation found that not only is rainwater now generally unsafe for human consumption, but that dangerously high PFAS levels have been detected in remote and sparsely populated regions, including Antarctica and the Tibetan plateau. Furthermore, the levels of PFAS reported exceed safe levels when compared to US and European guidelines. The immediate outcome of said exposure impacts society as a whole, as the lingering health effects (such as risk of cancer and impaired immune response) will lead to higher healthcare costs attributed to PFAS-related pathologies. Ian Cousins, lead author of the study explained the global ramifications, noting that although most populations living in the industrial world don’t directly drink rainwater, “many people around the world expect it to be safe to drink, and it supplies many of our drinking water sources.”

Though PFAS are literally raining down on us, you might do well to not willingly drink any, or ingest a mouthful of snow anytime soon.

Additional Information

Consult the following resources to learn more about PFAS: