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09/20/2006
Disruptors, Known and Unknown
Last April I took my trusty VW Jetta to the garage for service
and mentioned that my air conditioner wasn’t producing any cold
air. Sure enough, my service coordinator informed me there was
a leak in the condenser. However, he also said that he didn’t care
for air conditioning and preferred driving with the windows
open. I decided to give it a try, considering it was going to cost
$800 to fix and I’d already spent $500 for the servicing.
However, when the weather turned beastly hot, I was ready to
take the car back to the garage when a miracle happened. I
turned on the air conditioner and there was cold air! All summer
long the air conditioner has worked like a charm. This
experience with automotive refrigeration spurred my interest in
an article by Marc Reisch in the September 4 issue of Chemical
and Engineering News (C&EN). The article indicated that
forthcoming changes in automotive air-conditioning might
increase the price of an air-conditioned car by $40 to $1,000.
The story is one more example of how difficult it is to do right
by the environment. Take my 1997 Jetta. It’s likely that the
refrigerant that sprang to life is a hydrofluorocarbon known by
the catchy name of HFC-134a. The reason I think my car
employs HFC-134a is that, in the mid-1990s, car manufacturers
were switching from Freon and other chlorofluorocarbons, also
used as propellants in various pressurized products such as
shaving creams. They were disrupting the ozone layer. To
address the infamous hole in the ozone layer, most nations
endorsed the 1987 Montreal Protocol on Substances That
Deplete the Ozone Layer. This protocol called for switching to
refrigerants and propellants that wouldn’t deplete the ozone.
One of the refrigerants is HFC-134a.
The result is a wonderful example of scientists detecting a very
serious global problem and coming up with practical means to
correct it. The ozone layer is reestablishing its former self. With
the ozone problem being corrected by the use of compounds such
as HFC-134a, it’s rather shocking to find that the European
Union’s 25 countries have decided to ban the use of HFC-134a.
Why? While HFC-134a is good for the ozone layer, there’s the
problem of global warming. We all know about carbon dioxide,
CO2, as a prime cause of global warming. HFC-132a has a
“global warming potential” over 1,300 times higher than that of
CO2. According to the C&EN article, the fluorocarbons released
into the atmosphere are equivalent to about 10 percent of the
CO2 from fossil fuel as far as global warming potential is
concerned. The European Union, isn’t satisfied and will ban
HFC-132a in new cars in 2011 and by 2017 will ban use of any
refrigerant with a global warming potential greater than 150
times that of CO2. This means chemists are going to be tested
trying to come up with an acceptable substitute that is nontoxic
and nonflammable, as is HFC-132a. Stay tuned.
Global warming is certainly of tremendous concern but at least
we know the culprits such as CO2 and other compounds that can
exacerbate the situation. Knowing these, we can hopefully figure
out ways to minimize their emissions into our atmosphere before
it’s too late. Our waters also contain pollutants that can disrupt
our environment. Some are well known and publicized, such as
mercury in fish. With mercury, we can minimize our exposure
by simply restricting our consumption of fish.
Also worrisome are unknown contaminants in our water that
might cause cancer or other serious problems. The plethora of
bottled waters shows that many share this concern. Some time
ago, I mentioned a troubling finding in the Potomac River
watershed. The problem was that some male fish were found
that were quite abnormal in that they were bearing eggs. Brian
Trumbore called my attention to an article by David Farenthold
in the September 6 Washington Post that indicates the problem
of these “intersex” fish is now more widespread.
The fish in question are smallmouth bass and largemouth bass.
The first findings of immature eggs in the sex organs of male
smallmouth bass were in 2003 in a West Virginia stream. Last
fall researchers caught smallmouth bass in three tributaries of the
Potomac in Virginia and Maryland. A shocking 80% of the male
smallmouth bass contained eggs. At some sites, all of the fish
were growing eggs! There aren’t any smallmouth bass in the
Washington, D.C. area but there are largemouth bass. Seven of
13 male largemouth bass that were caught had some sort of
feminine characteristics and three of those contained eggs.
Vicki Blazer is a fish pathologist of the U.S. Geological Survey
and a leader in researching this problem. She feels the findings
indicate the possible presence of “endocrine disruptors”. These
are contaminants that somehow mess up the chemical signaling
that goes on in processes in the body. It appears that such a
contaminant, or perhaps a combination of contaminants, turns on
the process of egg formation that normally happens only in
females. For example, estrogen from humans and animals is
believed to be an endocrine disruptor.
The field of endocrine disruptors seems very complex and
controversial. An indication of this is the fact that, according to
the Post article, the U.S. Environmental Protection Agency was
charged by Congress in 1996 to develop a screening program for
endocrine disruptors but has as yet to test a single chemical!
EPA officials say the research is more complex than anticipated.
The millions of people in the Potomac watershed region are
concerned. Their water comes from the river and its tributaries.
While officials of the water companies believe they’re doing a
good job of filtering and treating the water, there is a question to
be answered. If you don’t know what chemicals are endocrine
disruptors, how do you test for them?
My wife and I had an experience with our own water last week.
She got a phone call offering free testing of our tap water. She
thought the call was from our water company, an impression that
I questioned and she called the water company. She was assured
it was legitimate. However, when the fellow arrived and set up
his testing, it was quickly apparent he was from a private
company selling water purification systems!
He was a nice, earnest young man and, thinking we might learn
something about endocrine disruptors or other contaminants, we
let him continue with his spiel and testing. All we learned was
that we had moderately hard water, that water from our bottle of
Poland Springs water had a much lower degree of hardness and
that it would cost about $5,000 for a purification system. We’re
living with our hard water!
Allen F. Bortrum
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