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AGENT ORANGE: IT’S TIME TO MOVE ON
The continuing search for more diseases caused by TCDD is not helping anyone
BY DAVID J. HANSON
The herbicide known as agent orange was
used for several years during the Vietnam War to defoliate forests to take
cover away from enemy soldiers.
Agent orange and other herbicides were
used from 1962 to 1971. The consequences of that practice promise to live on
for many decades.
Agent orange was a 50-50 mixture of 2,4-dichlorophenoxyacetic acid and
2,4,5-trichlorophenoxyacetic acid. Both of these compounds are considered
nontoxic to humans. The problem was that a
contaminant of the 2,4,5-T was 2,3,7,8-tetrachlorodibenzo-p-dioxin
(TCDD), which was discovered, while it
was being used, to be a very toxic
chemical.
Complaints from Vietnam veterans about
illnesses caused by their exposure to agent orange or TCDD began in the late
1970s. The issue quickly became a national issue, and by the mid-1980s,
Congress passed legislation mandating studies, testing, and compensation to
veterans who might have been exposed and harmed. Eventually, laws were passed
requiring that compensation be paid to Vietnam veterans who were diagnosed
with certain diseases associated with agent orange or TCDD.
Unfortunately, no one could ever figure out just who was exposed to the
herbicide. Records of aircraft sprayings and of troop positions did not match
up. Essentially, the government had to compensate any veteran who served
during herbicide spraying.
Still, the issue did not go away; it just grew. Congress required continual
reexamination of the veterans’ health for years. Now, more than 30 years
after the spraying stopped, two major studies are ongoing in the U.S. The
primary program is a continuing examination of the health of veterans who
actually worked with agent orange, loading and spraying the chemical in
Vietnam for Project Ranch Hand. These are the few people known to have been
exposed to TCDD.
The second is a literature review done by the Institute of Medicine to check
the status of possible human health problems from agent orange. Four biannual
reviews have been done so far; the latest was released last month. As in
previous iterations, the panel found an illness that, it says, may be
associated with exposure to agent orange. The IOM panel concluded that there
is an association between agent orange exposure and chronic lymphocytic
leukemia. The Department of Veterans Affairs has said this disease will be
added to others for which veterans can get disability compensation.
Most of the data linking any human disease with TCDD exposure come from
occupational exposures during herbicide manufacture many years ago. An
industrial accident in Seveso, Italy, also provides data. In both cases,
exposure to TCDD was orders of magnitude greater than any Vietnam field
soldier would have encountered.
An early study by the Centers for Disease Control & Prevention
found that the blood serum of veterans supposed to have been highly exposed
to agent orange had the same range of TCDD concentrations as that of soldiers
known to have never been exposed. The two groups could not be told
apart.
Why does the government continue to maintain that it can find concrete
evidence of diseases in veterans caused by low levels of TCDD exposure after
more than 30 years? If the men and women who served our country are becoming
ill because of that service, they deserve to be taken care of. But we need to
look beyond blaming just TCDD. Many of the people serving in Vietnam lived in
a sea of chemicals, drugs, disease, insects, mold, and bacterial infections
that could have had untold impacts on their future health. How can one relate
the possible impacts of all these exposures to the clinical results of
cellular changes caused by TCDD exposure found in a lab?
And the impact of assuming TCDD to be the cause of many ailments goes beyond
Vietnam veterans. TCDD, often just called dioxin, has become a favorite
chemical used by many environmental activist organizations to scare the
public. Despite the fact that TCDD concentrations in the soil and in people
have been falling for more than 20 years, dioxin is still held up as a big
chemical contamination issue.
Part of the confusion over this compound comes from the Environmental
Protection Agency, which, in its wisdom, lumped many chlorinated
dioxins, furans, and polychlorinated biphenyls (PCBs) into the same group,
saying that their structure made them likely to react similarly in the body.
This group is simplistically called “dioxins” and is what most environmental
groups now mean when they use the term without qualification. But much of the
physiological impact of this group actually comes from the PCBs in the mix
because they are of much higher concentrations than the actual dioxins,
especially TCDD.
Pressure on the government to do something for veterans with health problems
found a scapegoat in TCDD. EPA has fumbled around with an assessment of
dioxins’ toxicity for year and years, unable to come to clear conclusions.
Industry, meanwhile, has eliminated most known sources of TCDD contamination,
leading to the decline in environmental occurrence.
After 30 years and numerous studies, the government will probably never have
the kind of irrefutable and reliable data on agent orange and TCDD that it
needs to prove that they caused illnesses in Vietnam veterans. Similarly, the
government will probably never pin down what caused illnesses in Persian Gulf
War veterans. Perhaps it is time for government researchers to shift the time
and energy expended on agent orange to some of the other serious health
problems in the world. And, as the U.S. faces future combat in Iraq, it is
worthwhile remembering that in both training and combat, the armed forces
face injuries, exposure to dangerous environments, and death.
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