Subject: RACHEL: Potent Immune Poison

From: [email-masked] (Peter Montague)
Date: Wed, 2 Nov 1994 16:59:01 -0500

=======================Electronic Edition========================

            RACHEL'S ENVIRONMENT & HEALTH WEEKLY #414
                     ---November 3, 1994---
                           HEADLINES:
               POTENT IMMUNE SYSTEM POISON: DIOXIN
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POTENT IMMUNE SYSTEM POISON: DIOXIN

The immune system is a complex set of specialized cells and
organs that defends the body against attack by "foreign"
invaders.  When it functions properly, the immune system fights
off diseases caused by bacteria, viruses, fungi, parasites, and
cancer cells.  "When it malfunctions, however, it can unleash a
torrent of diseases, from allergy to arthritis to cancer to
AIDS," according to the federal National Institutes of Health
(NIH).[1]

At the heart of the immune system is the ability to distinguish
between self and nonself.  A healthy immune system protects the
"self" and attacks only the "nonself."  Virtually every cell in
your body carries distinctive molecules that identify it as self.
Cells lacking a "self" marker are quickly perceived as
"foreign," attacked, and eliminated by the immune system.

The National Institutes of Health (NIH) describes the immune
system this way: "The immune system, which equals in complexity
the intricacies of the brain and nervous system, displays several
remarkable characteristics.  It can distinguish between self and
nonself.  It is able to remember previous experiences and react
accordingly: once you have had chicken pox, your immune system
will prevent you from getting it again.  The immune system
displays both enormous diversity and extraordinary specificity:
not only is it able to recognize many millions of distinctive
nonself molecules, it can produce molecules and cells to match up
with and counteract each one of them.  And it has at its command
a sophisticated array of weapons.

"The success of this system in defending the body relies on an
incredibly elaborate and dynamic regulatory-communications
network. Millions and millions of cells, organized into sets and
subsets, pass information back and forth like clouds of bees
swarming around a hive. The result is a sensitive system of
checks and balances that produces an immune response that is
prompt, appropriate, effective, and self-limiting."[1]

The immune system can fail in two ways: if it is damaged, it can
fail to attack foreign invaders, and can thus allow infections or
cancers to develop.  On the other hand, if the immune system
fails to distinguish self from nonself, it can overreact and
attack the self, causing "autoimmune" diseases such as arthritis,
asthma, lupus, or Type I diabetes (insulin-dependent diabetes
mellitus).  Other autoimmune diseases include scleroderma,
Graves' disease, Addison's disease, Hashimoto's disease,
myasthenia gravis, lymphocytic adenohypophysitis (also called
Sheehan's syndrome), mucocutaneous candidiasis, Schmidt's
syndrome, and autoimmune thyroid disease.

Dioxin: Potent Immune System Poison

U.S. Environmental Protection Agency's (EPA's) 1994 draft
reassessment of dioxin emphasized that dioxin damages the immune
system directly and indirectly.  From studies of rats, mice,
guinea pigs, rabbits, cattle, marmosets, monkeys, and humans, EPA
concludes that even low doses of dioxin attack the immune system.
Dioxin directly reduces the number of B cells (immune cells that
develop in the bone marrow, then circulate throughout the blood
and lymph, fighting off invaders).  And it reduces the number of
T cells (immune cells that develop in the thymus, then circulate
throughout the body, attacking invaders), but dioxin's attack on
T cells seems to be indirect.  EPA says, "One potentially
important indirect mechanism is via effects on the endocrine
system.  Several endocrine hormones have been shown to regulate
immune responses, including glucocorticoids, sex steroids,
thyroxine, growth hormone, and prolactin. Importantly, TCDD
[dioxin] and other related compounds have been shown to alter the
activity of these hormones."[2,pg.9-49]

EPA goes on to say, "It is important to consider that if an acute
exposure to TCDD even temporarily raises the TCDD body burden at
the time when an immune response is initiated, there may be a
risk of adverse impacts even though the total body burden may
indicate a relatively low average TCDD level."  In other words, a
single dose of dioxin at the wrong time may damage your immune
system's ability to protect you.

EPA then says, "Furthermore, because TCDD alters the normal
differentiation of immune system cells, the human embryo may be
very susceptible to long-term impairment of immune function from
in utero [in the womb] effects of TCDD on developing immune
tissue."  In other words, dioxin can prevent the immune system
>from  developing properly in an unborn child, with lifelong
consequences, EPA believes.  "Animal studies suggest that some
immunotoxic responses may be evoked at very low levels of dioxin
exposure," EPA says.[2,pg.9-50]

Linda Birnbaum, director of research at the U.S. EPA Health
Effects Laboratory in Research Triangle Park, N.C., was the
leader of EPA scientific team reassessing dioxin.  She says,
"Dioxin appears to be a carcinogen in fish, rodents, and other
mammals, including humans.  But dioxin can also modulate [modify]
the immune system resulting in an inability to fight disease.  It
is a very powerful immunosuppressant. But it can also upregulate
[excite] the immune system so that you start becoming
hypersensitive, developing autoimmunity and allergies. Depending
upon the stage [of growth] of the animal and the species,
sometimes you observe immunosuppression and in other cases you
observe upregulation."[3,pg.4]

Birnbaum goes on to describe Taiwanese children, exposed to
dioxin-like chemicals, who had unusually frequent respiratory
infections and ear infections (otitis).  Further, she described
an Inuit population in Quebec with elevated levels of dioxin in
their bodies from eating the fat of marine mammals (seals); their
children have "very high incidences of respiratory infections and
otitis [ear infections], and also a very decreased take of
vaccinations," Birnbaum says.[3],pg.11 In other words,
vaccinations don't work well in these children, perhaps because
their immune systems have been damaged.

Birnbaum says there is no threshold for immunotoxic responses to
dioxin;[3,pg.14] in other words, there is no level of dioxin
below which the immune system is not affected.  Put another way:
any amount of dioxin seems to do some damage to the immune
system, at least in animals; there is no "safe" dose.

In laboratory mice, a single tiny dose of dioxin causes increased
deaths when the mice are challenged with an influenza virus.[4]
It is worth emphasizing that the effective dose of dioxin is very
small: 10 nanograms of dioxin per kilogram of bodyweight (10
ng/kg) harms the mouse immune system enough to increase the death
rate from influenza virus.  To get 10 ng/kg into perspective,
consider that a single 5-grain aspirin tablet taken by a
150-pound adult is a dose of 4.7 MILLION nanograms of aspirin per
kilogram of bodyweight (4,761,936 ng/kg).  For an adult human to
get a dose of aspirin equivalent to the dose of dioxin that harms
the mouse immune system, you would have to divide a single
aspirin tablet into 470,000 pieces (nearly half a million pieces)
and eat only one piece.  Is the human immune system as sensitive
to dioxin as the mouse's?  No one yet knows.

What about animals more human-like than mice?  Tom Webster of the
Boston University School of Public Health cites evidence that the
number of immune cells in rhesus monkeys is changed by a dioxin
body burden of 270 ng/kg; in marmosets, the number of immune
cells is changed at only 6 to 8 ng/kg of dioxin.  "While the
medical implications of this effect are unknown, it appears to
occur at about the average human body burden of dioxin-like
compounds," he says.  In other words, average residents of North
America carry 7 to 9 ng/kg in their bodies now, and 6 to 8 ng/kg
alters the immune systems of marmosets.[4,pg.8]   "Similar
effects [immune cell alterations] were seen in the children of
mothers who lived in dioxin-contaminated Times Beach, Missouri
during and after pregnancy," Webster notes, citing work by Gerson
Smoger and others.[4,pg.7]

This past summer, German researchers published a study of the
health of 158 chemical workers who had been exposed to dioxin in
1953 during an industrial accident at a BASF chemical plant.[5]
The 158 exposed workers were compared to 161 unexposed workers.
The dioxin-exposed workers experienced more frequent infections
and parasitic diseases during the 36 years after exposure,
consistent with immune system damage.  Especially noticeable were
increases in respiratory infections, thyroid diseases, disorders
of the peripheral nervous system, and appendicitis.  Mental
disorders were also increased.  All together, the highly-exposed
group had 18% more recorded episodes of illness than the control
group.

Ironically, the largest source of dioxin entering the environment
today is medical incinerators.  Together, medical incinerators
and municipal solid waste (msw) incinerators account for 95% of
all dioxin emissions into the air of the U.S., according to U.S.
EPA.[6,pg.2]  The good news is: these technologies are not needed
and could be phased out rapidly, if public health authorities
began to take their DISEASE PREVENTION responsibilities
seriously.  Plans for new incinerators could be easily abandoned.
For both medical wastes and municipal wastes, alternatives
already exist that are cleaner, safer, and less expensive.  (The
chief appeal of incinerators is political: massive campaign
contributions by the waste industry.)

Unfortunately, instead of planning to phase out incinerators, EPA
has announced plans to "regulate" incinerator emissions more
tightly by requiring air pollution scrubbers.  Scrubbers will not
decrease dioxin production, but will move dioxin from the air
emissions into the incinerator ash, which gets buried in shallow
pits in the ground. Thus, current public health policies are
creating a legacy of unpleasant surprises for our children.
                                                --Peter Montague
===============
[1] Lydia Woods Schindler, UNDERSTANDING THE IMMUNE SYSTEM [NIH
Publication No. 88-529] (Bethesda, Md.: National Institutes of
Health, July, 1988), pg. 1.

[2] U.S. Environmental Protection Agency, HEALTH ASSESSMENT
DOCUMENT FOR 2,3,7,8-TETRACHLORODIBENZO-p-DIOXIN (TCDD) AND
RELATED COMPOUNDS. VOL. III OF III. [EPA/600/BP-92/001c]
(Cincinnati, Ohio: U.S. Environmental Protection Agency, August,
1994.)  This is the official draft of "Chapter 9" of the EPA
dioxin reassessment, also known as the "risk characterization
chapter." Available free while supplies last; telephone (513)
569-7562 in Cincinnati.

[3] Linda Birnbaum, GREAT LAKES WATER QUALITY BOARD 102ND
MEETING, CHICAGO, ILLINOIS, JULY 15, 1993, PRESENTATION BY LINDA
BIRNBAUM, U.S. EPA (Washington, D.C.: International Joint
Commission, Great Lakes Water Quality Board, Dec. 21, 1993), pg.
4.  Available from us for $4.00.

[4] Tom Webster, DIOXIN AND HUMAN HEALTH: A PUBLIC HEALTH
ASSESSMENT OF DIOXIN EXPOSURE IN CANADA (Boston: Boston
University School of Public Health, 1994), pg. 7, citing
unpublished work by Linda Birnbaum and others.  Available from us
for $4.00.

[5] Andreas Zober and others, "Morbidity follow up study of BASF
employees exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
after a 1953 chemical reactor incident," OCCUPATIONAL AND
ENVIRONMENTAL MEDICINE Vol. 51, No. 7 (July 1994), pgs. 479-486.

[6] Lynn Goldman, STATEMENT OF LYNN GOLDMAN, M.D., ASSISTANT
ADMINISTRATOR FOR PREVENTION, PESTICIDES AND TOXICS, U.S.
ENVIRONMENTAL PROTECTION AGENCY, SEPTEMBER 13, 1994 (Washington,
D.C.: U.S. Environmental Protection Agency, September 13, 1994).

Descriptor terms:  immune system; morbidity; nih; national
institutes of health; dioxin; incineration; taiwan; children;
bronshitis; upper respiratory infections; basf; occupational;
safety and health; times beach; mo; tom webster; linda birnbaum;
gerson smoger; epa; us environmental protection agency; germany;
thyroid; appendix; appendicitis; peripheral neuropathy; mental
health; medical waste; infectious waste; msw; municipal solid
waste; corruption; elections; campaign reform; campaign
contributions;