as though they may be, where tap water from the
homes has extraordinarily high lead levels that
are very unsafe for children. So we have to do a
better job of finding those problems and making sure people take the simple steps necessary to
avoid that exposure through use of Brita filters
or flushing or other approaches or even bottled
water. But in general, the state of tap water in the
United States is very good.”
With traditional health threats like bacterial
contamination largely under control, scientists are
tackling new challenges, such as corrosion caused
by new disinfectant and others that many people
do not even suspect exist. Some even result from
well-intentioned efforts to conserve this precious
resource. Here again is Dr. Edwards:
“As you know, water conservation is moving to
the forefront as we try to become more sustainable, and that means lower-water-use shower
heads, using rainwater or reclaimed water to
flush toilets, and other issues. One of the things
we are discovering is that because we are not
drawing as much freshwater into the home, the
quality of water is sometimes adversely impacted,
meaning a few years ago you would flush the
toilet and you would draw large amounts of
freshwater into your house. But nowadays, we
are using less of that water for flushing of toilets,
showers, and those types of activities. The potable water just sits in the line for much,
much longer periods of time. So just like milk can go bad if it stays around too long, so
too can potable water go bad, and we are discovering this is a downside of water conservation, and that we’ve got to come up with ways to maintain this higher water for a
longer period of time in our house as it sits. So there’s always new challenges, and that can
involve changing the water treatment so that the water stays fresher longer, to oversimplify
the problem. Or changing the type of plumbing materials involved so that they might have
a lesser impact, or can preserve the purity of water for a longer period of time.”
Conclusion
We face enormous challenges in meeting global needs for clean water. Some of the roadblocks are not strictly scientific. They result from extreme poverty and national priorities
that limit use of existing water purification technology. However, as these glimpses of chemistry’s responses show, progress is being made. Here is Dr. Whitesides:
“Drinking water is really a tough problem because it involves a commodity, which people
use a lot of and they want at very low cost. So I have to be candid and say that parts of
this problem strike me as extremely difficult. It is a problem of getting pure water — a
problem that would benefit enormously from smart chemists thinking in creative ways.
We just desperately need as many new ideas as possible about how to purify water.”
Smart chemists. Innovative thinking. That’s the key to solving global challenges of the 21st
century. Please join us at ACS for the next chapter in this ongoing saga of chemistry for life.
In our next special Global Challenges podcast, we’ll examine what could be a magic bullet
for water shortages — efforts to put water on a salt-free diet and produce freshwater from
the limitless resource of H O in the oceans.
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