Study: Rainwater Worldwide is Contaminated with PFAS

New study eviscerates another fantasy that we can slip away off the grid and  escape the backlash of a modern industrial, nationalistic world.

It’s something I’ve long suspected: collecting rainwater from your roof as a potable drinking source comes with serious health exposure. First, you have the fact that some of the stuff on your roof, notably asphalt-modified shingles, are about as healthy to drink from as chewing on automobile tires. 

Now there’s something just as ominous, and hard to filter. A new report from the University of Stockholm has  found that "Based on the latest US guidelines for PFOA in drinking water, rainwater everywhere would be judged unsafe to drink."


And by everywhere, the report means Per‐ and polyfluoroalkyl substances (PFAS and POFA) are found everywhere on Earth. Not only are some of these PFAS carcinogenic, but they’re also linked to birth defects and many other health issues.

Another Domino Falls

We know extreme heat events are increasing. We know wildfire smoke is heavily polluting our air for half the year. Now we can add pervasive poisoning of our freshwater supply. None of it is inexplicable, of course, least of all the PFAS problem. 

The toxins come directly from industry: Teflon coating, fire retardants, packaging, electronics, cosmetics, and other chemical processes that were supposed to make life “better.” 

Of course, as the report points out, not many Americans drink rainwater directly. On the other hand, millions around the globe do, and millions of us in this country get our tap water indirectly from nearby lakes and reservoirs. But what happens to them every time it rains? They get a dose of poison from the sky.  

As this water enters our municipal pipelines, it’s generally not tested thoroughly, not filtered adequately, and not studied enough. It ends up in our food, our drinking water, our baby formula, and even our homegrown edible plants.

So what’s to be done? At this point, we’re cursed with dealing with this industrial waste, because it hangs around “forever.” The companies that make them, most notably 3M, claim to be “phasing out” their production, but their website touts the fact that they are still making them today.  

“Today, PFA compounds are manufactured by various companies, including 3M, and are used in everyday products. As part of 3M’s philosophy and policy to continually improve its products and minimize their impact on the environment, the materials used by 3M have been tested and assessed to assure their safety for intended uses. In addition to providing this data to regulatory agencies, much of this data is publicly available.”

I’d call that kind of doublespeak greenwashing. A reckoning may be coming. Some consumer groups are calling for industry to pay for the cost of purging these toxins from the environment.


Source: EWG

Let’s bust a few myths about our water safety, as it relates to PFAS and POFA.

Myth: Bottled water is a safe haven. Nope, bottled water is not required to be tested for PFAS.

Myth: Cities filter our water supply and remove PFAs. Most do not. A study this year by EWG mapped 2,858 sites in 50 states and two territories with PFAS contamination (see map). One problem is that only certain filter types remove PFAS, such as reverse osmosis membranes, and many water treatment facilities are not equipped with the right filtration gear.

Myth: Humidifiers are ok though, right? Negative. If you read between the lines on the EPA website, they recommend using only distilled water in your humidifier if you have PFAS in your water, not exactly an “all clear.”

Myth: Showering, baths, and cooking are safe though, right?  That depends on what you consider “safe.” Again, read what the EPA says.  They urge you to take short showers and baths and not to let small children drink any of their bathwater. As for cooking, they note thatPFAS exposures from the water used for cooking are usually smaller than PFAS exposures from other sources, like grease-resistant food packaging.” How do you feel about small doses of PFAS every time you cook?

Myth: A diverter on your roof solves the problem.  Wrong again. We used to think that a diverter, which “dumps” the first gallons of water from your roof, removing heavy metal-laced backwash, was good enough. But this method won’t affect PFAS-contaminated rainwater.

Myth: Rainwater is safe for plants. Nope. According to the Minnesota department of health, edible plants can uptake PFAS into the edible parts of the plant. That’s bad news. They actually suggest that you only use filtered water to water your gardens, grow certain kinds of plants and so on.

A Deep Malaise

You see how deep this problem goes. There’s literally no place to hide, with the narrow exception of costly and water-wasting reverse osmosis systems. We need a complete halt to the production of PFAS today, not in some far-off future.

Awareness about PFAS couldn’t really come at a worse (or is it better?) time, as freshwater levels drop to record lows in much of the world. How, in good conscience, can we continue to pollute the life-giving blue gold that we all need to survive and be healthy?

I urge you to take action on this matter. Find out if your local water utility tests and filters PFAS. Vote for politicians willing to address the PFAS pollution crisis. The alternative is an increasing divide between those who can afford expensive filtration systems and those forced to rely on dangerous water supplies.

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