American tap water? It's considered some of the safest in the world. Yet countless Americans shun th...

1. Hexavalent Chromium, Cancer-Causing Toxin, Common in
Tap Water: What to Do
American tap water? It's considered some of the safest in the world. Yet countless Americans shun
the stuff that flows from faucets and fountains and buy bottled water instead.
<br>&amp
;lt;br>What's really in the stuff and why does it cost 3,000 times
more than tap?
<br>&amp
;lt;br>Here <a
href="http://www.pacinst.org/about_us/staff_board/gleick/&
amp;amp;amp;amp;amp;quot;>Dr. Peter
Gleick</a>, the author of
"Bottled and Sold: The Story Behind Our Obsession with Bottled
Water," shares 10 of the most shocking facts about bottled
water. istockphoto
(istockphoto)
(CBS) Americans worried about the safety of their drinking water may have new cause for alarm.
A new study shows that tens of millions of us are drinking water contaminated with hexavalent
chromium, a cancer-causing toxin that garnered national attention with the 2000 feature film "Erin
Brockovich."
Recent tests found hexavalent chromium, a.k.a. chromium-6, in the drinking water of 31 of 35 cities
tested, according to a statement issued by the Environmental Working Group, the Washingon, D.C.-
based advocacy group that conducted the tests. Among the cities with the highest levels were
Norman, Okla., Honolulu, and Riverside, Calif.
The study, the first of its kind to be made public, comes at a time when the EPA is considering
whether to implement a national standard for hexavalent chromium in drinking water, the
Washington Post reported. The compound was deemed a "probable carcinogen" by the National
Institutes of Health in 2008. It's been linked to stomach cancer and leukemia, as well as other health

2. conditions, Jane Houlihan, senior vice president of research for the group, told CBS News.
Where is the hexavalent chromium coming from? It's discharged by steel and pulp mills, as well as
from metal-plating and leather-tanning facilities, according to the group's statement. It can also
appear in tap water as a result of erosion of natural deposits.
Brockovich helped residents of Hinkley, California sue Pacific Gas & Electric, alleging that the
company leaked hexavalent chromium into the town's drinking water for more than 30 years,
according to the Post. The company paid $333 million in damages and pledged to clean up the
contamination.
What does Brockovich say now about hexavalent chromium?
"This chemical has been so widely used by so many industries across the U.S. that this doesn't
surprise me," she told the Post. "Our municipal water supplies are in danger all over the U.S. This is
a chemical that should be regulated."
In the meantime, what can consumers do to limit the threat posed by hexavalent chromium?
"With levels this high, it's critically important that people begin to think about filtering their water,"
Houlihan said. Unfortunately, inexpensive carbon filters like the ones in filtration pitchers and tap
faucet filtration units aren't good at removing hexavalent chromium, she said, adding that reverse-
osmosis filtration systems costing hundreds of dollars were a much safer bet.
Bottled water is another option, but all the plastic bottles aren't very good for the environment, she
said.
Given its vital role in protecting human health, Houlihan said there's one thing consumers should
definitely not do about water stop drinking it.
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