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#463 - Dioxin and Health, 11-Oct-1995

The word "dioxin" stands for a group of chemicals that occurs rarely,
if ever, in nature. A very large proportion of dioxin comes from human
sources. Dioxin began accumulating in the environment around 1900 when
the founder of Dow Chemical (in Midland, Michigan) invented a way to
split table salt into sodium atoms and chlorine atoms, thus making
large quantities of "free chlorine" available for the first time.[1]
(Dow's chlorine is "free" in the sense of "chemically unattached," not
free in the sense of "without cost.") Initially, Dow considered free
chlorine a useless and dangerous waste. But soon a way was found to
turn this waste into a useful product, attaching chlorine atoms onto
petroleum hydrocarbons and thus creating, during the 1930s and 1940s, a
vast array of "chlorinated hydrocarbons." These new chemicals, in turn,
gave rise to many of today's pesticides, solvents, plastics, and so
forth. Unfortunately, when these chlorinated hydrocarbons are processed
in a chemical plant, or are burned in an incinerator, they release an
unwanted byproduct --dioxin --the most toxic family of chemicals ever

Dioxin is released by paper mills, by metal smelters, by many chemical
plants, by many pesticide factories, and by all incinerators. According
to Greenpeace chemist Pat Costner, the biggest source of dioxin
discharges into the environment is factories that make the popular
plastic, PVC (polyvinyl chloride).[2] Industry and EPA (U.S.
Environmental Protection Agency) have known much of the bad news about
dioxin since at least the late 1970s, but have done little or nothing
about it. In 1991, the paper industry and the Chlorine Council (a trade
group) pressured EPA to relax the few dioxin standards that EPA had set
at the time; in response, EPA has spent the last 4 years re-examining
the toxicity of dioxin, in preparation for deciding what to do about
it. (See REHW #269, #270, #275.) EPA released a draft of its 9-volume
"dioxin reassessment" last year (see REHW #390 and #391). Yesterday,
EPA's Science Advisory Board released its own critique of the 9-volume
"dioxin reassessment."[3]

So-called "conservatives" in Congress have attacked Chapter 9 of EPA's
dioxin reassessment --the chapter that contains most of the chillingly
bad news about dioxin. We reported in REHW #457 that Congress was
preparing to pillory EPA scientists in a public hearing; that hearing
has been delayed, and perhaps has been scrapped completely.
"Conservatives" in Congress complain that Chapter 9 has not been
adequately "peer reviewed."

Last month the main authors of EPA's Chapter 9 published --in a peer-
reviewed journal --their own conclusions about the toxicity of dioxin.

The basic message from these senior EPA scientists is that dioxin is
toxic to humans in surprisingly many ways, and that the general public
is not adequately protected from ill effects by a traditional "margin
of safety." Public health policy usually aims to keep the public's
exposure to poisons at least 100 times below levels known to harm
humans or animals. As we will see, this new report from EPA shows that
U.S. adults are already carrying around an average dioxin burden in
their bodies that is remarkably close to the levels known to cause
illness in humans or animals.

We want to note at the outset that all of the results reported here
were taken from peer-reviewed literature and were statistically
significant. All of the following information is taken from the new EPA

EPA'S LATEST FINDINGS: EPA says the average U.S. citizen has no
particular exposure to dioxin besides what is routinely eaten in food -
-mainly in red meat, fish, and dairy products. This routine dietary
exposure has produced an average body burden that is estimated to be 13
nanograms of dioxin per kilogram of body weight (ng/kg). (A nanogram is
a billionth of a gram; a gram is 1/28th of an ounce. A kilogram is
about 2.2 pounds.) Ng/kg is equivalent to parts per trillion. So 13
ng/kg seems tiny --and as an absolute quantity it is. But compared to
the amount that causes havoc in dioxin-exposed animals and humans, 13
ng/kg qualifies as a major public health problem, in our opinion. (EPA
estimates that 5% of Americans --some 12.5 million people --have body
burdens twice the average.) Here are some effects of dioxin, as
reported by EPA:[4]

CHLORACNE: Chloracne was the first disease associated with exposure to
dioxin, first described in 1897. Chloracne appeared as an occupational
problem in the 1930s among pesticide workers, and among workers who
manufactured industrial chemicals called PCBs [polychlorinated
biphenyls]. However, dioxin was not identified as the cause of
chloracne until about 1960. (Dioxin was an unwanted contaminant of the
pesticides and PCBs.) Chloracne produces skin eruptions, cysts and
'pustules' --like a very bad case of teenage acne, except that the
sores can occur all over the body and in serious cases can last for
many years. To grasp the nature of a bad case of chloracne, we can
recall Dr. Raymond Suskind's description of one of his patients, a
white man who got chloracne from dioxin exposure in a Monsanto chemical
plant in West Virginia in 1949: "... he has given up all social and
athletic functions and remained in his house, according to his own
description, for months on end. Several times he has been mistaken for
a Negro and forced to conform with the racial segregation customs of
the area. This has happened on buses or in the theatres [sic]," Suskind

In laboratory animals, chloracne occurs at body burdens as low as 23
ng/kg and as high as 13,900 ng/kg; in humans, chloracne has occurred at
body burdens as low as 96 ng/kg and as high as 3000 ng/kg. This means
that some humans get chloracne when their dioxin body burden is only 7
times as high as the body burden of the average person in the U.S.
today. In other words, there is not even a factor of 10 separating the
average person from the possibility of chloracne. In fact, the EPA
study cites examples of humans getting chloracne with body burdens only
3 times as high as the U.S. average.

CANCER: There have been 5 peer-reviewed studies showing cancer in
humans exposed to dioxin. The exposures occurred through accidents or
through routine activities at work. These studies of humans show that,
for some human populations, the danger of cancer begins to rise
noticeably when the dioxin body burden reaches 109 ng/kg. This means
that a cancer effect in humans is evident when the dioxin body burden
reaches a point 8 times as high as the average dioxin body burden in
the U.S. public. Again, there is not a factor of even 10 separating the
average American from the possibility of cancer from dioxin.

monkeys (marmosets) reveal learning disabilities in young monkeys with
a dioxin body burden as low as 42 ng/kg.[6] Thus learning disorders are
evident in monkeys who have a dioxin body burden only 3.2 times as high
as that of the average American. Again, there is not a factor of even
10 separating the average U.S. resident from the possibility of a
dioxin effect on the central nervous system.

DECREASED MALE SEX HORMONE: Researchers at the National Institute of
Occupational Safety and Health (NIOSH) found reduced levels of
testosterone --male sex hormone --circulating in the blood of dioxin-
exposed male workers.[7] Other sex hormone levels in these men were
affected as well. If we can assume that dioxin exposure caused the
diminished testosterone levels, then some humans are 280 times as
sensitive as rats are, from the viewpoint of testosterone. What seems
most important is that these dioxin-exposed workers had body burdens
only 1.3 times the dioxin body burden of the U.S. population. Thus
there is not even close to a factor of 10 separating the average U.S.
male from the testosterone effects seen in dioxin-exposed workers. The
reduction in testosterone levels was statistically significant, but the
reduction was small and the measured levels still remained within the
range that is considered normal.

DIABETES: In two studies, an increased incidence of diabetes has been
reported in dioxin-exposed Vietnam veterans; a third study that reaches
similar conclusions was reportedly released last week by the U.S. Air
Force.[8] The body burdens that seem to produce an increase in diabetes
range from 99 to 140 ng/kg. Thus the average American, with a body
burden of 13 ng/kg, is a factor of 8 below the lowest level thought to
create a diabetes hazard. Once again, there is not even a factor of 10
separating the general public from the levels though to cause health
problems in dioxin-exposed people.

IMMUNE SYSTEM TOXICITY: In monkeys (marmosets), changes in white blood
cells associated with the immune system can be measured at dioxin
levels of 10 ng/kg --25% below the level already found in average
Americans. Mice with body burdens of 10 ng/kg --25% below the amount
already found in you and me --display an increased susceptibility to
infections by viruses, presumably because their immune system has been

SPERM LOSS AND ENDOMETRIOSIS. Female rhesus monkeys with body burdens
only 5 times as high as the U.S. average have a measurable increase in
the painful, debilitating disease of the uterus, called endometriosis.
Endometriosis is increasing in U.S. women. (REHW #364, #377.) Male
offspring of rats with a body burden only 5 times as high as the U.S.
average have diminished sperm production. During the last 50 years,
sperm production of men through the industrialized world has dropped
50%. (REHW #343, #432.)

CONCLUSION: We have only scratched the surface of the bad news that has
accumulated about dioxin. It is an astonishingly versatile and potent
poison. EPA, and the corporations that release dioxin into the
environment, have waffled and fudged for 20 years or more. The answer
to this burgeoning public health problem is clear, if not easy: over
the next 20 years, we must ban chlorine as an industrial feed stock and
thus cut off the source of all dioxins. What other choice do we have?

--Peter Montague


[1] Jack Weinberg, editor, DOW BRAND DIOXIN (Washington, D.C.:
Greenpeace, September, 1995); 34 pages, $15.00, from Sanjay Mishra at
Greenpeace: (202) 319-2444.

(Washington, D.C.: Greenpeace, February, 1995); $15.00; available from
Sanjay Mishra at Greenpeace: (202) 319-2444.

[3] Copies of the Science Advisory Board's dioxin critique are
available, while supplies last, by phoning (202) 260-8414.

[4] Michael J. DeVito and others, "Comparisons of Estimated Human Body
Burdens of Dioxinlike Chemicals and TCDD Body Burdens in Experimentally
(September, 1995), pgs. 820-831.

Kettering Laboratory, April, 1950), pg. 9.

[6] S.L. Schantz and others, "Learning in monkeys exposed perinatally
to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)." NEUROTOXICOLOGY AND
TERATOLOGY Vol. 11 (1989), pgs. 13-19. And see: R. Bowman and others,
"Behavioral Effects in Monkeys Exposed to 2,3,7,8-TCDD Transmitted
Maternally During Gestation and During Four Months of Nursing."
CHEMOSPHERE Vol. 18 (1989), pgs. 235-242.

[7] Grace M. Egeland and others, "Total Serum Testosterone and
Gonadotropins in Workers Exposed to Dioxin," AMERICAN JOURNAL OF
EPIDEMIOLOGY Vol. 139 (1994), pgs. 272-281.

[8] Reuters reported October 6 on a new 20-year study of Air Force
veterans exposed to Agent Orange. Reuters said the new study shows that
dioxin-exposed vets have an increased incidence of diabetes and heart
disease. We believe the new study is available from Donna Tinsley at
the Air Force; phone (202) 767-4587. Thanks to Pat Costner of
Greenpeace for this intelligence.

Descriptor terms: dioxin; chlorine; dow chemical; epa; studies;
pesticides; solvents; smelting; pulp and paper industry; pvc; pcbs; epa
science advisory board; food safety; diet; meat; milk; dairy products;
fish; chloracne; cancer; learning disabilities; central nervous system;
testosterone; androgens; occupational safety and health; diabetes;
ranch hand study; vietnam veterans; immunotoxicity; viruses; sperm
count; endometriosis; greenpeace; pat costner;