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NUNLEY: It's Living on Earth. I'm Jan Nunley. Last month the Environmental
Protection Agency warned that Washington, DC's water and sewer system
is so decrepit that it may pose a risk to the health of millions
of residents. Meanwhile a Milwaukee study suggests that low levels
of biological contaminants could cause chronic gastrointestinal
problems. These are the latest in what sometimes feels like a flood
of alarming news about the water we drink. As a society we're still
grappling with how much protection of drinking water we can afford.
But till that's resolved, families and individuals with a little
money to spare can take steps now to improve the quality of the
water they drink. Jeffrey Martin is a chemist for Consumer Reports
who's studied drinking water and home filtration systems. He says
it's what you can't see that can hurt you most.
MARTIN: If you have water that smells bad or tastes or looks bad,
that's clearly objectionable and you might want to do something
about it. But the ironic part is that the things which are probably
more harmful, things like lead which is a chronic hazard, won't
get you in the short run but eventually it could if it's high enough,
and immediate threats which can occur unpredictably like cryptosporidium
and bacterial contamination. Those are the things you can't taste
or see, and they're really more dangerous than the aesthetic problems.
NUNLEY: How can you determine if something like that is in your
water?
MARTIN: Lead, for example, can be tested for. There's reliable
chemical tests that are quite sensitive for lead. But the usual
problem with other things, which are microbiological contaminations
which have been in the news lately -- cryptosporidium, for example,
which was a problem in Milwaukee about a year ago, and even in New
York City there have been periodic low levels of it -- those are
very hard to predict. They're hard to find and there's really nothing
you can do as far as testing your own water to prevent it. They
can just occur at a moment's notice. Although it's rare.
NUNLEY: If you're concerned about your water, what kind of filter
systems are available to use? And start with the simplest thing
and then we can go to the more complex systems.
MARTIN: Okay, well the simplest things are the ones that are selling
like hotcakes these days. Those are the carafe water pitchers. Those
are quite effective actually in improving the aesthetic qualities
of your water. And in some tests we recently did at Consumer Reports
we found actually that the carafe water pitchers that you can buy
are quite competent at removing lead as well as organic chemicals
from the water.
NUNLEY: Okay, so the carafe, and then what?
MARTIN: Then you can go up to the filters, small filters which
fit on the end of your faucet. Then there are the ones which sit
on your counter top and connect to your faucet with a hose. Then
you can go to under sink models, where you actually plummet the
water under your sink through a filter and then it comes up sometimes
to a separate tap on the sink. Then there are even larger models
which are intended to process the water for your whole house.
NUNLEY: Are there any scams to watch out for in the whole water
filtration business?
MARTIN: You betcha. If you're paying for a filter which is say
about a foot high and 4 or 5 inches in diameter, a cylinder about
that size, you shouldn't pay more than $100 or so for it. And for
a counter top or an under sink filter, one, two, $300 is usually
enough for one that has quite a large capacity.
NUNLEY: I'm assuming in the case of some of those bacterial contaminants,
it would be a good idea to change out that filter fairly regularly.
MARTIN: As far as filtering goes, it's very hard to have a filter
which will effectively remove all those things and then stay clean.
If, say, a slug of bacteria or something gets into your filter,
carbon can be a very effective medium for them to grow on, and there's
lots of stuff in there, sludge and algae and everything. So bacteria
can grow on filters, and if you have one you need to replace the
filter at a regular interval.
NUNLEY: Or you might end up with worse water than you had to begin
with.
MARTIN: You certainly can.
NUNLEY: Isn't there also a recommendation that you use cold water
for certain applications, not hot water? Particularly if there's
a danger of lead contamination?
MARTIN: That's a very good rule. You should never use hot water,
the hot water tap, for any cooking or drinking purposes. It's, as
you say, has sat in the pipes for a long period of time. It's sat
in the water heater. Not that that produces any real problem, but
if there's lead in the lines it will have higher lead content than
the cold water.
NUNLEY: So better to run cold right out of the tap.
MARTIN: Right. And if you live in an area, say, in an inner city
or an older section of some of our older cities, especially in the
East, we found that it's not a bad idea to let your water run 30
seconds before you take the first cooking water in the morning.
NUNLEY: And it's not going to be that much in terms of wasting
water.
MARTIN: No, you can water your plants with it if you really want
to.
NUNLEY: All right, great. Jeffrey Martin is a chemist for Consumer
Reports. Thank you so much for being our guest, Jeffrey.
MARTIN: You're welcome.
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