Purified Nature's Way

The Top of the Water Cycle
Credit: Lorrie Von, Photographer

Tapping Ino Trouble?

In Search of Healthy Drinking Water

Most of us don't spend much time thinking about what's in our tap water or whether we are drinking "healthy water".  We're busy with far more important things, like how to pay the mortgage, the insurance, the car payment, and save for retirement.  The good news is that our tap water can help at least with the last problem by cutting short our retirement years.  I'm joking, of course, but that doesn't mean there's not at least a grain of truth in my humor.  

Before I go on, I want to make clear that I'm not bashing tap water, or the systems and regulations that make most of it perfectly safe for watering our lawns, washing our cars, and flushing our toilets.   In fact, Americans use, on average, between 80 and 100 gallons of water per day[1],  while drinking less than one quarter of a gallon[2].   This means that less than one quarter of one percent of tap water is actually consumed as drinking water, so it makes little economic sense to purify tap water to the same level as drinking water.  And whatever complaints we may make about our tap water, water-borne pathogens, which were once a leading cause of disease and death, are now extremely rare in western countries.

There are way more than five reasons to filter your drinking water, or at least to drink filtered water, but few of us will want to read the other few thousand reasons.  So here are my top five: 

1. We're Made of Water

Well, not completely, but over 60% of the human body is water.  And over 70% of our brains and muscles are water[3].   Since that's the case, drinking water that contains anything other than water seems intuitively to be a bad idea.  There are studies that support this, but for now I'll let your intuition guide you.  

What we can say with certainty is that water is the main vehicle for transporting nutrients within our bodies, and for carrying wastes out of it.  There is also no question that human bodies are extremely good at filtering our drinking water.  But unlike most non-living water filtration systems, we don't really have any easily replaceable parts.  The bottom line is that you can either buy a filter, or you will be a filter.   If you'd rather not be a filter, you can learn all that you need to know to find a filter or filtration system with a little careful research. 

2. Chlorine Kills Things

This is not all bad, since chlorine kills bacteria, viruses, and many other pathogens that invade our water.  And as long as chlorine makes it to the tap but no further, it's great for protecting us from pathogens.  But because it kills things, it has some inherent properties that make it undesirable for drinking, and your intuition again may have already brought this to your attention.  Does the smell of  public pool make you thirsty?  Do you savor that first gulp from a glass freshly filled from a municipal tap?  

Most of us can taste chlorine in concentrations as low just o.5 parts per million, and most of us really don't like the taste or the smell.  It's probably why the average American only drinks 3.9 cups of water per day, and why at least 30 percent of Americans don't routinely drink water at all[2].   Smelling and tasting bad are chlorine's way of cluing us in to it's nature, sort of like the rattle that a rattlesnake makes to warn you before it strikes.  And in fact, studies have shown that chlorine combines with organic compounds to form trihalomethanes and other "disinfection byproducts", which do cause cancer.  

While there is not much scholarly evidence linking just the chlorine used to disinfect drinking water with serious health effects, there is at least anecdotal evidence that suggests such connection[3].  There is admittedly a lot of hype and disinformation propagated by those with commercial interests in water filters.  (Full disclosure: I have commercial interests in water filters, but I studiously avoid hype and disinformation.  And I drink filtered water.)  There is also very compelling evidence linking the byproducts of chlorine with serious health effects, so don't dismiss the dangers.  The good news is that the same filtration methods that remove chlorine from water are generally good at removing the more dangerous byproducts, too. 

3. Fluoride

Not all water systems add it intentionally, but as of 2012, about 210 million Americans were drinking fluoridated tap water[5].   Considering that Americans drink only about one quarter of one percent of their tap water, and that nearly 30 percent of Americans don't drink any of their tap water at all, it seems insane to fluoridate the tens of billions of gallons of water that Americans flush down their toilets, spray on their lawns, or wash their clothes in.  But I'm just being judgmental.  

Or maybe not: The Department of Health and Human Services just lowered the standard for fluoride in drinking water from a range of 0.7 to 1.2 milligrams per liter (mg/l) to just 0.7 mg/l.   While the standard was purportedly lowered due to concern that some small percentage of the 210 million Americans drinking fluoridated water might get mottled teeth, some research links fluoride intake with brittle bones, decreased birth rates, kidney stones, and reduced intelligence in children[6].

Personally, I'd like my children to have every advantage they can get.  I don't want them going through life with mottled teeth just because some bureaucrat thought they'd better off with fewer cavities even if it means they'll also be stupid.  Am I missing something? 


Credit: John Lief, MD

4. Chlorine Doesn't Kill Everything

This doesn't usually get a lot of attention, but there are plenty of organisms that can survive chlorine.  Some of them exist in "biofilms", slick sheets of huddled bacteria that attach themselves to the insides of pipes and become resistant to chlorine.  These biofilms can harbor and nurture harmful microbes and other organism that can then be "slow-released" into a tap water system.  

According to EPA, water within a public supply system that is treated with chlorine is not sterile, but contains living organisms that do not succumb to disinfection.  Normally, this isn't a problem either because the surviving organisms aren't pathogens, or because they are so few in number that they don't cause disease.  At least, they don't cause disease in enough people that we really notice.  But occasionally there is a widespread outbreak, like when cryptosporidium infected the Milwaukee, Wisconsin public water supply system in 1993 and sickened over half a million people.  While it's true that that was far and away the largest disease outbreak associated with public water supplies in US history, it's also true that it could happen again.  It's not uncommon to hear public water system spokesmen telling their patrons to boil water before drinking it, particularly in the winter.   I'd rather not find out after it's too late that I've been drinking water that is contaminated, so I prefer to filter AND sterilize my water rather than relying on the water supply system to tip me off when they get around to it.  

5. Pharmaceuticals and Human Hormones in Tap Water

This is actually the most compelling reason for filtering your drinking water, so I've saved it for last.  In 2008, the Associated Press published an article that disclosed the results of an extensive study showing that at least 46 million Americans were exposed to traces of various medications and human hormones in their drinking water[7].  In one case, a municipal water system found five separate pharmaceutical chemicals, including a tranquilizer.  Human hormones, apparently associated with the increased use of birth control pills, were also found in many municipal water supplies.  

By now you may be asking yourself how in the world pharmaceutical chemicals and human hormones find their way into our public water systems.  This is actually a very good question, but, unfortunately, it has a very bad answer: Since the human body often does not use all of the prescription and non-prescription medications that so many of us take  daily, a percentage of these compounds pass through the body and are excreted.  Yes, you read that right, excreted.  As in "excrement", or perhaps "urine", or perhaps even saliva, who really knows?   Once excreted, these chemicals then pass through toilets, and thus make their way through who-knows-what route into our tap water.  What's your intuition telling you now?  

You may be comforted to learn that, while pharmaceutical chemicals in various combinations and concentrations are present at very low levels in public water supply systems, there is no evidence linking these chemicals with any adverse health effects.  Lest you find too much comfort in that, there really are no studies that have evaluated the cumulative and long-term effects of chronic exposure to shifting and random combinations of pharmaceuticals.   

Final Thoughts

These five reasons were more than enough to convince me that drinking water needs to be filtered and filtered well.  There are many more reasons, but to twist Renee Zellweger's famous words to Tom Cruise in Jerry Maguire, "They had me at pharmaceuticals in my drinking water."   That's all I needed to know to stop drinking unfiltered water.

It's time to stop thinking of tap water and drinking water in the same terms.  Tap water is fine for flushing toilets, especially since we know from the pharmaceuticals in it that at least some of it has already made that trip.  But it is not fine for drinking for the reasons I've listed and many more.   

Distillation, reverse osmosis, de-ionization, and other filtration or treatment methods can turn your tap water into drinking water.  Until then, don't drink it.