Wednesday, October 15, 2008

The Big Bottled Water Scare

If this blog has no other redeeming value, I'd like to think that at the very least it serves the role of media watchdog for the legal and scientific issues where my expertise is more than that of a layperson. In that tradition, I'd urge all my readers to pay no mind to the latest pseudo-scientific scare about bottled water, which is seemingly "as polluted" as tap water.

Having been in the business of water testing for most of the last decade, I'm more than a little familiar with what's what. And what's so disturbing about these sorts of stories isn't just the scientific misinformation, but the way that misinformation is repeated verbatim by the media. I've made this point before, that when George Bush (or Barack Obama or John McCain at this point) make any sort of claim, you better believe that the media will thoroughly examine what's been said. Yet when a public interest group or environmental organization releases the results of a study, their press releases are taken as the gospel truth. There's no investigation, not a moment spent to question whether the organization in question is shaping their data in such a way that, you know, fits neatly with their politics.

In this case, this bottled water survey was done by the Environmental Working Group, an organization that advocates for stricter regulation. To be fair to the Fox News story I linked to, they do point out this fact and they also even manage to get in a statement from the bottled water industry.

An industry group branded the findings "alarmist." Joe Doss, president of the International Bottled Water Association, said the study is based on the faulty premise that a contaminant is a health concern "even if it does not exceed the established regulatory limit or no standard has been set."

The problem is, without context, all you have is an industry rep saying bottled water is fine and an environmental organization with their big study about how scary bottled water is. So what I offer today is context, for those of you who care about such things.

# The headline of the story "bottled water as polluted as tap water" is essentially correct, but misleading. The drinking water supply in this country is cleaner and safer than just about any drinking water supply anywhere, anytime, in the history of the world. Unless "polluted" somehow means "okay to drink," than I have trouble seeing how it is an apt description for bottled or tap water.

# Bottled water is less regulated than tap water as it is not subject to the Safe Drinking Water Act, which only regulates actual water systems. However, all bottled water is tested annually and many companies perform additional testing throughout the year. And perhaps more importantly, a majority of bottled water actually comes from municipal supplies that are already tested under the Safe Drinking Water Act. Dasani (bottled by Coke) and Aquafina (bottled by Pepsi) are nothing more than tap water that's been additionally filtered and bottled for resale.

# The major "contaminants" cited in the study are disinfection byproducts. To understand what a disinfection byproduct is, just deconstruct the word. A disinfection byproduct is literally a byproduct of the disinfection process, or in other words, the chemicals that are produced in low levels when a water system treats it's drinking water supply in order to prevent, say, a cholera outbreak of the sort that killed thousands in Peru in the early 90's. Disinfection byproducts are a tricky issues for regulators, scientists, and water system experts alike, given the need to balance potential outbreaks of waterborne illness with the possibility of future incidents of cancer. As the story notes, federal limits- the limits that your tap water supplier is probably following is 80 parts per billion. California, as is their norm, has adopted a 10 parts per billion rule that's of questionable public health benefit.

# Wal-Mart's claims that their own tests did not show any high levels of disinfection byproducts are not BS. Disinfection byproduct levels vary, depending upon the time of the year and the specifics of the treatment being utilized by the water system. More importantly, as anyone who's ever worked in a lab will tell you, different tests can simply give you different results.

Also noted in the Environmental Working Group's report:

Altogether, the analyses conducted by the University of Iowa Hygienic Laboratory of these 10 brands of bottled water revealed a wide range of pollutants, including not only disinfection byproducts, but also common urban wastewater pollutants like caffeine and pharmaceuticals (Tylenol); heavy metals and minerals including arsenic and radioactive isotopes; fertilizer residue (nitrate and ammonia); and a broad range of other, tentatively identified industrial chemicals used as solvents, plasticizers, viscosity decreasing agents, and propellants.

Again, this is nothing more than a scare tactic, worrying those who don't have any context. First, many of these scary pollutants occur naturally in the environment at low levels, including many metals, minerals, and even radioactive isotopes. To call water polluted because, say, it comes from a watershed that's naturally high in manganese seems to defy any meaningful notion of what pollution actually is. And more importantly, we're exposed to low levels of hundreds of chemicals every day in going about our day-to-day life. The real question isn't what chemicals you can find, but whether or not we're exposed to chemicals at a level that could have an impact upon our health. The fact that they don't give us any results here indicates to me that we're talking about extremely low levels of everything mentioned above.


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