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Water used to be simple. It came out of a tap; you drank it; and it
was good. Now, with concerns about safety and taste, water is much more
complicated. After contacting the experts and scouring the research,
here are the answers to the most important water questions.
Where do we get our tap water?
There are generally two sources of water -- ground (underground) and
surface (reservoirs, lakes, rivers, etc.), and it's about a 50-50
split. Larger cities typically use surface water, whereas smaller
municipalities use ground. Also, according to James M. Symons, Sc.D.,
aka Dr. Water, about 80 million people in the United States use water
from individual sources (e.g., well water), which is not regulated.
Is tap water safe?
To state the obvious, if water weren't safe, most of the country would
be sick. So, in the short term, most municipalities have safe water.
The risk associated with tap water relative to other risks in the
world, such as air and traffic accidents, is very low, says Mark
Wiesner, Ph.D., P.E., a professor of environmental engineering at Duke
University. The primary concern for municipal water facilities is to
eliminate pathogens or microbes -- the things that can make you sick
right away. American water systems are doing a decent job keeping our
water supply safe, so we can feel a level of comfort drinking the water
from the tap.
Water from your tap is not meant to be sterile, but it is meant to be
safe to drink within a reasonable risk. The Environmental Protection
Agency (EPA) regulates known contaminants and, through a process known
as risk assessment, monitors the frequency and concentration of
contaminants. The Safe Drinking Water Act mandates that the agency
continually update its list of potential contaminants.
In fact, the EPA has two sets of water-quality goals. The first is the
EPA maximum contaminant levels (MCL), which municipalities can't go
above. Then there are the MCLG (maximum contaminant level goals). Here
the objective is to determine what the goals would be if cost weren't
an issue. Both these levels are available on the EPA Web site.
However, environmental groups are concerned about the long-term effects
of tap water. Can you get cancer or lead poisoning from the water? The
fact is that we don't know -- and that's what's frightening.
The Environmental Working Group analyzed the nation's municipal water
supply and found over 90 percent compliance with enforceable health
standards set by the EPA, demonstrating a commitment on the part of
municipalities to comply with safety standards. The problem, according
to the group, is the EPA's failure to establish enforceable health
standards or to monitor requirements for other sources of tap water
contaminants. Of the 260 contaminants detected in tap water from 42
states, the EPA has set enforceable health limits for only 114; the EPA
also has set non-enforceable goals, called secondary standards, for
five others.
Of the 141 unregulated contaminants detected in public water supplies
from 1998 to 2003, 52 are linked to cancer, 41 to reproductive
toxicity, 36 to "developmental toxicity" and 16 to immune system
damage, according to chemical listings in seven standard government and
industry toxicity references. Despite the potential health risks, any
concentration of these chemicals in tap water is legal, no matter how
high.
Cities may also be concerned about nitrates and nitrites, too much
fluoride, pesticides and a vast number of other organic chemicals,
endocrine-disrupting chemicals, etc. "There are so many that it is
ludicrous to list what the consumer should avoid, since the consumer
can't actually identify any of them," says Tim Ford, Ph.D., a professor
of microbiology at Montana State University.
The Environmental Working Group database of contaminants --
www.ewg.org/tapwater/contaminants/ -- has a detailed listing of all
contaminants you should be concerned about, both those regulated and
unregulated by the EPA.
The other issue with regard to municipal tap water is the potential
problems created by the chemicals used to clean and disinfect the
water. "Long-term effects of disinfection byproducts are hotly debated.
Yes, many have been shown to be carcinogenic at high concentrations,
but if we didn't have disinfection, we'd die of infectious disease long
before the effects of disinfection byproducts kill us from cancer,"
says Ford.
Why is tap water contaminated?
The biggest problem we have with tap water is the source. Because
rivers and reservoirs are often polluted with industrial chemicals,
farm waste, sewage, pesticides, fertilizer and sediment, municipal
water supplies start with a very contaminated supply, which they're
forced to clean up. "We are paying for a lot of current and past sins,"
according to Symons.
How is tap water cleaned?
According to Symons, the two primary means for preparing water in this
country are disinfection (using primarily chlorine) and filtration.
It's best if the water is clarified (filtered) to remove all particles,
because germs hide inside particles. But some municipalities, such as
New York City, only chlorinate, he adds.
Why don't municipalities take additional steps to purify tap water?
There's no point in "sterilizing" water that is then going to be
distributed through an aging, leaking distribution system (which
currently is almost all of them), says Ford. But most tap water is
treated to overcome most of the post-treatment distribution issues that
could occur.
Also, one interesting fact about water treatment: According to Wiesner
at Duke University, all municipal water is treated to be drinkable;
however, only 15 percent goes for residential use (and only 15 percent
of that 15 percent is actually used to drink and cook -- the rest is
used for bathing, gardening, washing cars, etc.). So no matter where
you drink, American water is probably safe -- from the fire hydrant,
hose, a swimming pool, etc.
Is there another country with a superior water supply?
The United States creates regulations based on available data of the
risks and hazards, whereas Europe has a precautionary system. If they
think there is something that's going to be wrong -- well, they don't
let it out on the market. For instance, synthetic polymers are used to
remove viruses from water in the United States, but they're banned in
many European countries because there is not enough health information,
says Wiesner.
If I drink tap water, should I use a filter?
One of the weakest points of tap water is the distribution system, and
while treatment is supposed to hold up through this process, there can
be some deterioration. "It's not an unreasonable investment to have
some sort of carbon filter to remove lead, bacteria and chlorine. It
can be a bit safer and also improve the taste. But keep in mind that
you're taking on the responsibility of treating water at the last step
of the process -- which means you need to maintain the process," says
Wiesner.
If you are thinking about getting a filter for your home, there are
several things to consider. First, make sure your filter removes
contaminants of concern in your particular tap water. Second, be sure
the filter is independently certified by NSF International, a
not-for-profit, non-governmental organization (www.nsf.org), or a
similar independent organization. Third, maintain the filter at least
as often as the manufacturer recommends, or hire a maintenance company
to maintain it for you. Carefully follow all cleaning, replacement or
routine maintenance instructions. "Refrigerators with built-in filters
are worrisome. Supply lines will eventually form biofilms and are
virtually impossible to clean. There are many, many different filters
on the market, but here, maintenance is the key. The simpler they are
to clean and replace, the better," says Ford.
Also, remember that a "point of use" filter on your sink will not
remove all contaminants. For example, you can be exposed to
trihalomethanes in the shower. Only a "point of entry" device that
cleans all the water in your house will take care of all your water
taps.
Finally, if you have a weakened immune system, check the Centers for
Disease Control Web site and consult with your health care provider for
advice about filters.
How can I find out about the quality of the water where I live?
All community water suppliers have to produce what is known as a
Consumer Confidence Report once a year and make it available to their
customers. You can call to find out where your city's information is
posted or if they can mail you a report, says Aaron Margolin, Ph.D., a
water expert and professor of microbiology at the University of New
Hampshire. To find out about your city's water quality, ask your water
company for a copy of its annual water-quality report, which is
sometimes called a right-to-know report. Then get the brochure called
"Making Sense of Your Right to Know Report," (see
www.safe-drinking-water.org/rtk.html or
www.epa.gov/safewater/dwinfo/index.html) to help you understand the
report.
The Environmental Working Group has compiled a great source to check
the contamination of drinking water provided by more than 39,751 water
utilities in 42 states. For the first time, you can see how your tap
water stacks up against other cities and towns throughout the country.
http://www.ewg.org/tapwater/yourwater/
Do you want to test your drinking water?
Although primarily designed for unregulated well water, you can get a
test kit from Underwriters Laboratories, a not-for-profit testing
company, at www.uldrinkwell.com for $165 plus some additional charges.
The kit tests for 53 contaminants, including bacteria, metals,
inorganics and volatile organic compounds.
CHARLES
STUART PLATKIN is a nutrition and public health advocate, author of the
bestseller Breaking the Pattern (Plume, 2005), The Diet Detective's
Count Down (Simon & Schuster, 2007) and founder of Integrated
Wellness Solutions. Copyright 2006 by Charles Stuart Platkin. Sign up
for the free Diet Detective newsletter at www.dietdetective.com.
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