Remember the movie Erin Brockovich? Whether or not you saw it, you probably know that the Julia Roberts character was an ordinary gal-turned-activist (based on a real person) who learned that there were cancer-causing chemicals in her town's water and raised hell until justice was served. After all of the hype surrounding that movie you probably assume that the chemical in question isn't in your water right now, right?
Well you'd be wrong, at least if you live in one of 31 cities on a list that the Environmental Working Group just released. The EWG tested the drinking water in 35 American cities and found that same chemical, called hexavalent chromium or chromium-6, in 31 of them (you can see the list of cities tested here).
Why is this a problem? Because it's widely believed that chromium-6 causes cancer, especially gastrointestinal tumors. Despite the fact that the EPA classifies this type of chromium as "likely to be carcinogenic to humans" the federal government hasn't set a legal limit for it and doesn't require municipalities to test the water for it. The state of California is considering setting a limit of 0.06 parts per billion on the chemical, and 25 of the cities tested exceed that limit (the water from one city, Norman, Oklahoma, contains 200 times that much).
And if you take certain medications or have certain medical conditions, you should be especially concerned about chromium-6. You see, it's believed that stomach acid converts at least some chromium-6 to a harmless form of chromium called chromium-3, or trivalent chromium, but if your stomach acid is low you'll be exposed to more of chromium's toxic form. Here are some of the factors that put you at greater risk (from the EWG report):
A low-acid stomach can be caused by several widely used medications, such as antacids and proton pump inhibitors used to treat common disorders including gastroesophageal reflux disease, peptic ulcer disease and chronic gastritis. Other conditions that can inhibit stomach acid production include pernicious anemia, pancreatic tumors, infection with Helicobacter pylori (a common bacterium linked to ulcers), mucolipidosis type IV and some autoimmune diseases. People with pernicious anemia have also been found to absorb hexavalent chromium more readily."
Sooo, does this mean that you should sign up for bottled water delivery? Not necessarily, since there's no guarantee that bottled water doesn't contain hexavalent chromium as well (plus it can be expensive and moving around all those heavy bottles of water is bad for the environment).
The good news is that there is one reasonably affordable home filtration system that removes chromium-6 from tap water: Zero Water pitchers, which have a special "ion exchange" filtration system that removes even more contaminants than the other countertop pitchers do (unfortunately, the most well-known filtration pitchers, including the one that I currently use, contain "activated carbon" filters, which do not remove chromium). To find out more about which water filters remove what, check out the NSF website (it's an independent non-profit that researches and certifies such things).
It doesn't look like my city, San Francisco, was tested, but other major California cities landed on the list, so it's making me think about investing in a new water filter system—either a Zero Water pitcher, or even one of the more expensive systems that goes under the sink.
Is your city on the list? And if so, are you worried? Are you going to do anything about it?