EWG's Bottled Water Study: Alarming Results and Breast Cancer Implications
Posted Dec 23 2008 9:44pm
The Environmental Working Group published its study of bottled water. Among ten major brands plucked from retailers nationwide, EWG found thirty-eight different contaminants. EWG recommends drinking filtered tap water, ideally from a glass or a Kleen Kanteen stainless steel water bottle.*
Here are some of the contaminants found:
Disinfection byproducts...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.
Bottled waters from Sam's, Walmart, and Giant stores were called out in particular. EWG cites a double standard where bottled water suppliers are not required to report on water quality, while muni water districts have to report tap water test results regularly to consumers. (The depressing part is that munis don't have to test for pharmaceuticals and most water filters do not remove many man-made substances. Welcome to Prozac Nation, whether or not you wanted it.)
Here is one of the more alarming findings, regarding estrogen mimics and breast cancer:
The study also included assays for breast cancer cell proliferation, conducted at the University of Missouri. One bottled water brand spurred a 78% increase in the growth of the breast cancer cells compared to the control sample, with 1,200 initial breast cancer cells multiplying to 32,000 in 4 days, versus only 18,000 for the control sample, indicating that chemical contaminants in the bottled water sample stimulated accelerated division of cancer cells. When estrogen-blocking chemicals were added, the effect was inhibited, showing that the cancer-spurring chemicals mimic estrogen, a hormone linked to breast cancer. Though this result is considered a modest effect relative to the potency of some other industrial chemicals in spurring breast cancer cell growth, the sheer volume of bottled water people consume elevates the health significance of the finding. While the specific chemical(s) responsible for this cancer cell proliferation were not identified in this pilot study, ingestion of endocrine-disrupting and cancer-promoting chemicals from plastics is considered to be a potentially important health concern (Le 2008).
It's increasingly clear that estrogens are a big driver of breast cancer. Estrogen can take the form of xenoestrogens like those found in these bottled water samples or pesticides, phytoestrogens like those in soy (with increasing evidence that flax might be a contender as well), and in chemical estrogens that we take in the form of birth control pills.
In fact, doctors who perform thermograms - an early breast cancer risk screening tool - have noticed that 80% of women today display estrogen dominance patterns in their breast images, compared to only 40% ten years ago. One of the ways to reverse estrogen dominance is to apply bioidentical progesterone cream to the breasts in the luteal phase of the menstrual cycle. Doctors also say that strict soy avoidance has worked for many patients.
I try to limit my use of plastic bottled water, so if you see me with one every once in a while, know that I'm trying to suppress all this information since thirst has overwhelmed me!
* I favor the Kleen Kanteen over the more popular SIGG water bottle since SIGG's aluminum bottles are lined with an undisclosed "polymer" that is tested for currently known plastic contaminants. Since chemicals are put on the market before they are tested for human safety, and an increasing number of plastic chemicals are implicated in health problems, I prefer to stick with old-fashioned stainless steel.