What
You Should Know
About Your Drinking Water
The
U.S. and Canada, as well as most other industrialized nations,
have a right to be proud of their drinking water. Safe public
water is one of the triumphs of the last century.
This
does not mean that there's nothing to be concerned about. Constant
vigilance, research, and new investment are essential. Some
drinking water may contain lead or dangerous levels of arsenic.
Private wells, like municipal water supplies, need regular monitoring.
Keeping the water supply safe is an ongoing concern of the governmentand
of the people.
Public
drinking water
Your
local water supplier is required by law to notify you if there's
any reason your water is unsafe. Furthermore, the Safe Water
Drinking Act requires all water suppliers to issue their customers
an annual report on the source and quality of the waterincluding
a list of contaminant levels. Municipal water is tested for
micro-organisms, organic and inorganic chemicals, disinfectants,
disinfectant by-products, and radioactive substances. If your
copy of the report has not come in the mail, call your water
company.
Though
your water company is responsible for keeping the water safe,
lead can get into the supply after the water has left the treatment
plant. Arsenic may also be a problem in some areas, mainly the
Southwest.
A
well of your own
About
40 million Americans and 4 million Canadians get their water
from private wells. If you are one of them, water safety becomes
your own responsibility.
Any
water system can be affected temporarily by spills, agricultural
runoff, including pesticides, and short-term treatment problems.
And private wells can contain lead or arsenic. Your local health
department can tell you which contaminants are typically found
in your area. It can also supply a list of certified labs to
test the water for you. You can also call the EPA Safe Drinking
Water Hotline for a list of labs (see below).
If your water proves substandard, you can use a filtration systemanything
from a filtering pitcher to an elaborate point-of-entry system
that filters all the water coming into your house. You can also
consider bottled water.
You
may want a filtration system even if your water is safesimply
to improve the taste or to remove excess minerals. The National
Sanitation Foundation (NSF), an independent, nonprofit organization,
is a good source of information on filters. It tests products
and certifies that they meet certain standards.
Organic
pollutants: microorganisms
Parasites
such as Giardia and Cryptosporidium,
which are transmitted via animal and human waste, are removed
by proper filtration (chlorination alone is not sufficient).
If Cryptosporidium gets into the water in large amounts, it
can cause serious illness and death, as in an outbreak in Milwaukee
in 1993, in which 100 people died and 400,000 were sickened.
But municipal water systems usually do a good job of controlling
such parasites, and of warning the public if the water does
become contaminated.
What
to do: If you discover that your water has Cryptosporidium,
particularly if someone in your household has a weakened immune
system (due to chemotherapy, for instance, or infection with
HIV), boil the water for a minute or two. Some filtration systems
remove parasites. NSF can tell you which filter to buy.
Inorganic
pollutants
Lead.
The dangers of lead poisoning are well known, especially for
children and pregnant women. Lead gets into water via plumbing:
service lines, pipes, solder, and brass faucets, especially
when they're new. Even lead-free copper pipes may be soldered
with lead. Soft water (that is, with low mineral content) is
more acidic than hard water and thus more likely to leach lead
out of pipes. Lead was banned from plumbing pipes in 1986 (though
the ban did not take effect in some states until 1988), but
even the newest faucets may still contain some lead.
To
test for lead, which is important if a woman in your household
is pregnant or if you have infants or small children, call the
local health department or your water company, which may offer
free testing, or contact the EPA. Testing is usually inexpensive
and can reveal whether the problem, if any, comes from the service
line outside or from pipes and faucets in your house. (You send
a first-draw sample to the lab, and another sample after running
the water for a specific time, so it's possible to tell which
pipes are the source of any lead.) Be sure you use a government-certified
lab.
If
you do have a high level of lead (over 15 parts per billion
in the first-draw sample, or 5 parts per billion in later samples),
consider installing a point-of-entry or under-the-sink reverse-osmosis
filtration device (see below). If the later samples show high
lead, notify your water supplier.
For less severe problems, use a filtering pitcher or a faucet-mounted
filter. Check the NSF certification on the filter to make
sure it removes lead.
If the lead comes from the faucet, let the water run for one
minute before drinking it or cooking with it, particularly
if the water hasn't been run for several hours. And don't
use hot water for cooking, drinking, or mixing infant formula.
Hot water dissolves lead more quickly than cold. You can also
replace your faucets with low-lead ones.
By-products
of chlorination. Most Americans (80%) drink chlorinated
water. Chlorine kills many harmful microorganisms, including
those that cause cholera, typhoid, dysentery, hepatitis, and
other waterborne diseases. Thus chlorination has saved countless
lives and is one reason for the great increase in life expectancy
since 1900.
But
chlorination has its downside. While it's effective against
bacteria, it kills only some viruses, such as polio and the
Coxsackie virus. Chlorine undergoes many changes when added
to water. It turns into hypochlorous acid, which combines with
practically anything, including bacteria (they die in the process,
which is how disinfection works). In very large amounts, the
by-products of chlorine increase the risk of cancer. Whether
these chlorine by-products are harmful in trace amounts has
been under study for many years. As a result of recent research,
the EPA has set new limits on the amount of such by-products
permitted in waterregulations that will go into effect
in December 2001.
According
to the EPA, chloramine is increasingly replacing inorganic chlorine
for treating water in the U.S.; it is less likely to produce
potentially harmful by-products. Ask your water company what
it is using.
Arsenic.
This natural element, highly poisonous in large amounts, can
leach into the water from the ground or from industrial waste,
and it can be expensive for water systems to eliminate it. Constant
low levels of arsenic increase the risk of bladder, lung, and
skin cancer. Currently, under a standard set almost 50 years
ago, the allowable level of arsenic is 50 parts per billion.
These levels, according to the National Academy of Sciences,
pose a lifetime cancer risk of 1 in 100 if you drink about two
quarts of water a day. (No food additive that posed such a high
risk would be allowed on the market.) The EPA was preparing
to reduce permissible levels to 10 parts per billionlevels
that many experts still consider too high. But the decision
was postponed by the Bush administration until next February.
Unless
you live in central California, Nevada, New Mexico, or Arizona,
it's unlikely that your water has high levels of arsenic.
What
to do: If you live in one of those areas, ask your local
utility about the arsenic content of your water. If you have
a private well, call the EPA for a list of labs that can check
this for you. If your water proves to have a high arsenic content
(higher than 10 parts per billion, which is the standard set
by the World Health Organization), consider installing a distilling
device or reverse osmosis filter.
If
you choose to use bottled water to avoid arsenic, be sure you
obtain a certificate from the supplier that the arsenic content
in what you're buying is below 10 parts per billion (equal to
10 micrograms per liter).
Filtering
the water
If
you are simply trying to improve the taste of your water, a
filtering pitcher will do. But if you are trying to remove lead,
arsenic, or specific contaminants, you may want a permanent
installation. Before you buy, be sure you know which contaminants
the system will filter out. NSF is an excellent source of information.
Water
filtration systems come in two basic types, ranging from cheap
to expensive:
Point-of-entry systems are installed
on the main water supply and treat most or all the water entering
a house. These include water softeners, which remove calcium
and magnesium. There's no harm in drinking softened water,
and it does not cause heart disease, as has been alleged.
But the softer the water, the more likely it is to leach lead
from the pipes.
Point-of-use systems include
faucet-mounted filters, faucets with built-in filters, pitchers,
and under-the-sink filters.
Whether
it's installed under the sink or at point-of-entry, the most
effective filter is a reverse-osmosis system, which filters
out lead and other toxic metals and other contaminants. This
type of filter can be expensive ($500 to $1,000 or more) and
the cartridges have to be replaced every year at a cost of up
to $200.
Faucet-mounted
systems and faucets with built-in filters work well against
specific contaminants (check the labels and NSF certificates),
as do most countertop pitchers. Simpler systems such as these
represent a small investment, but replacement filters can cost
as much as $100 a year.
Distilling
the water
For
about $100 to $500, you can get a countertop distiller that
will boil water and condense the vapor. Distilling reduces levels
of all chemicals in water, including heavy metals such as lead.
Some units kill microorganisms. Some also remove chlorine by-products.
Distilled water is tasteless and devoid of potentially beneficial
minerals, but there's no harm in drinking it.
Note
1: Distillers and reverse-osmosis filters remove fluoride.
If you use one, make sure your toothpaste contains fluoride,
and consider fluoride treatments for children in the household.
Note
2: With any filtration or distilling system, change filters
as directed; otherwise you risk increasing contamination.
Why not switch to bottled water?
Bottled
water, in spite of its phenomenal popularity, may not be safer
or more healthful than tap water. Some studies have found that
tap water tends to have lower bacterial counts than bottled,
and that some bottled waters are out of line with standards
for tap water. Some bottles, however, are just packaged tap
water.
In
addition, bottled water is costly and bulky. Plastic containers
are not as weighty as glass, but they can affect the water inside.
Clear polyethylene plastic has little or no effect. Thick opaque
containers can impart a plastic flavor. Big rigid polycarbonate
water-cooler jugs can leave chemical residues.
If
you care about conservation of resources, tap water is by far
the best choice, according to the World Wide Fund for Nature.
Millions of tons of plastic are used every year to make water
bottles; disposing of these bottles contributes to air pollution.
The
FDA regulates bottled-water safety using EPA water standards
and establishes definitions for labeling. If you buy bottled
water, you're probably better off buying brands bottled by members
of the International Bottled Water Association; NSF inspects
their plants.
For
more information
Environmental
Protection Agency (EPA): phone 202-260-5543. Safe Drinking
Water Hotline: 800-426-4791.
NSF International:
phone toll-free in U.S., 800-NSF-MARK; otherwise 734-769-8010.
For questions on consumer products, call 877-867-3435. To
get The Consumer's Guide to Safe Drinking Water, which lists
the water-treatment units tested by NSF and the contaminants
they remove, send $7 to NSF Inter-national, Consumer Affairs
Office, P.O. Box 130140, 789 N. Dixboro Road, Ann Arbor, MI
48113-0140.
Natural Resources
Defense Council: phone 212-727-2700.
Food and Drug
Administration (FDA): phone 888-INFO-FDA.
International
Bottled Water Association (IBWA): its members (accounting
for 80% of the water bottled in the U.S.) must test annually
for contaminants and are open to unannounced inspections by
NSF. Phone 703-683-5213 or its information hotline at 800-WATER11.
Reference
Source 98