=======================Electronic Edition========================
RACHEL’S ENVIRONMENT & HEALTH WEEKLY #457
—August 31, 1995—
News and resources for environmental justice.
==========
Environmental Research Foundation
P.O. Box 5036, Annapolis, MD 21403
Fax (410) 263-8944; Internet: erf@rachel.clark.net
==========
Back Issues | Index | Official Gopher Archive
To subscribe, send E-mail to rachel-
weekly-request@world.std.com
with the single word SUBSCRIBE in the message. It’s
free.
===Previous
Issue==========================================Next
Issue===
DIOXIN INQUISITION
People calling themselves “conservatives” in Congress are
preparing to flay U.S. Environmental Protection Agency (EPA)
scientists for their reassessment of dioxin –the agency’s 4-year
effort to determine the true hazards of dioxin. Dioxin is a
highly toxic byproduct produced in the manufacture of many
pesticides, and by the routine operation of all incinerators,
metal smelters, and chlorine-using paper mills. In 1986, EPA
concluded that dioxin was one of the two or three most powerful
poisons ever studied, and accordingly, set strict limits on
certain releases into water. As the agency moved to enforce
those limits in the late 1980s, industrial dioxin-producers
developed a strategy for reversing EPA’s stance: They would force
the agency to undertake a scientific reassessment of dioxin, a
reassessment they evidently thought they could control.
The paper industry took the lead in pressuring EPA to formally
reassess dioxin. (See RHWN #269, #270 and
#275.) On January 23,
1991, four chief executive officers of paper companies visited
William Reilly, who was then the head of EPA. The four executives
memorialized their meeting by sending Reilly a letter dated
January 25th –a letter that (thanks to Greenpeace) found its way
into the record of a public hearing on the dioxin reassessment
which EPA held in Washington, D.C. November 15, 1991. In their
letter, the four executives (John A. Georges, International
Paper; T. Marshall Hahn, Jr., Georgia-Pacific Corp.; Furman C.
Moseley, Simpson Paper; and Andrew C. Sigler, Champion
International) thanked Reilly for his receptiveness to their
ideas during the meeting January 23: “We were also encouraged by
what we perceived as your willingness to move expeditiously to
re-examine the potency of dioxin and chloroform in light of the
important new information that has been submitted with respect to
those chemicals,” the paper company executives said. They
rebuked EPA for “failure to act on the emerging health science.”
They told Reilly there is now a “prevailing view that low-level
dioxin exposures do not pose a serious health threat.” “Despite
this new reality,” they said, “EPA has taken no tangible or
timely steps to revisit its health criteria for dioxin, and has
even failed to temper the Agency’s zeal in acting on the worst
risk estimates….”
As a direct result, EPA’s “scientific reassessment” of dioxin was
born. By April, 1991, Reilly had geared up his agency for a major
effort to reassess the toxicity of dioxin, just as the paper
industry had requested. In August, just 4 months into the
multi-year study, Reilly told the NEW YORK TIMES how he expected
the dioxin reassessment to turn out: “I don’t want to prejudge
the issue, but we are seeing new information on dioxin that
suggests a lower risk assessment for dioxin should be applied,”
Reilly told the TIMES (August 15, 1991, pg. 1).
However, the scientific reassessment did not turn out as Reilly
and the paper industry supposed it would. EPA scientists
evidently took their mandate seriously. They designed a
reassessment process that involved original laboratory research,
many meetings with non-government scientists, at least 2 public
hearings, and many drafts of the 9-volume reassessment document,
which was peer-reviewed prior to release. Eight of the nine
volumes were written by non-governmental scientists. EPA had
never before involved such a large number of non-agency
scientists in its work. It managed to solicit and include the
viewpoints of industry, academia, government, and the general
public.
As a result, EPA scientists concluded a year ago that dioxin
probably causes cancer in wildlife and humans, and that it harms
the immune system and the reproductive systems in fish, birds,
and mammals (including humans) at doses that are miniscule. The
lead scientist on the EPA reassessment team, Dr. Linda Birnbaum,
said she and her colleagues now consider dioxin an “environmental
hormone” capable of disrupting a large number of bodily processes
in fish, birds, and mammals, including humans. Dioxin, EPA said,
is especially powerful in its effects on the unborn and the
newly-born. (See RHWN #290, #390, #391, and #414.) This was
hardly the outcome the paper industry had expected.
The final draft of the 9-volume reassessment document went to
EPA’s science advisory board (SAB) this year; at an SAB meeting
May 16, 1995, parts of the dioxin reassessment were criticized.
Specifically, the SAB asked EPA to provide better support for
some of the conclusions in Volume 9 (conclusions which we
summarized in RHWN #390 and #391), but
they did not tell EPA to
do any additional scientific work.
Using the SAB’s comments on the reassessment (which have not yet
been made public) as a political springboard, a group of
so-called “conservatives” of both parties in Congress are
planning to investigate “whether sound science is being distorted
for preconceived policy ends, and the potential economic impact
of future mandates based on this reassessment.” [1]
Congress has scheduled a public hearing Sept. 13 before the House
Subcommittee on Energy and the Environment of the Committee on
Science. It is widely understood in Washington that this hearing
is going to be a “witch hunt” aimed at punishing EPA for reaching
conclusions that the paper industry and other industrial
poisoners don’t like.
Everyone who has followed the story of tobacco during the last 20
years knows there are a handful of scientists who still claim
there is no compelling evidence that tobacco causes lung cancer
in humans. These “tobacco scientists” have counterparts in the
dioxin world, and this little group of dioxin denial specialists
will be showcased at the hearing September 13. They are expected
to say that EPA and its 100-or-so independent outside scientific
advisers have made a mountain out of a mole hill. Congress may
use their testimony as an excuse to further slash EPA’s research
budget, thus exorcising the source of much recent bad news about
dioxin.
Meanwhile, the scientific evidence linking dioxin to serious
reproductive disorders in mammals has continued to accumulate.
Just this month, Dr. Earl Gray (a respected EPA researcher)
published the third in a series of studies of the effects of a
single low dose of dioxin on rats and hamsters. This series
began with 3 studies published in 1992 by Dr. Richard E. Peterson
at the University of Wisconsin. [2]
In the Peterson studies, young male rats whose mothers were
given as little as 0.064 micrograms of dioxin per kilogram of
body weight showed consistently reduced levels of male hormones,
plus a variety of sex-related changes, including:
** smaller accessory sex organs, including smaller testicles;
** slower sexual maturation;
** distinctly feminine-style regulation of one hormone related to
testosterone production;
** greater willingness to assume a receptive-female posture when
approached by a sexually stimulated male.
Other effects revealed by the Wisconsin studies included:
** Even the lowest dose tested (0.064 micrograms of dioxin per
kilogram of the mother’s body weight), yielded consistent
reductions in a male offspring’s daily sperm production.
** The developing male reproductive system is more sensitive to
the effects of this hormone-like toxicant [dioxin] that any other
organ or organ-system studied.
** The unborn or newborn is about 100 times more sensitive to
dioxin than the sexually mature animal.
What do these studies mean for humans?
The Wisconsin researchers speculated, “Thus the findings from
this study raise the possibility that TCDD could potentially
affect sexually dimorphic behavior in man if exposure were to
occur during fetal development.” “Sexually dimorphic behavior”
refers to the bodily and behavioral differences between men and
women. Is it possible that homosexual behavior in some
individuals may be conditioned by exposure to chemicals before
birth? It seems to be so in laboratory animals, in wildlife, and
in some humans whose pregnant mothers were exposed to
diethylstilbestrol (DES), a powerful hormone. [3]
Commenting in 1992 on the Peterson rat studies (which she called
“highly significant”), Linda Birnbaum of EPA said, “The real
question is how general these effects are.” And if these effects
occur in another species? “I would get very concerned [about the
potential human-health implications],” Birnbaum told Janet
Raloff, a reporter for SCIENCE NEWS. [4]
In March, 1995, Birnbaum herself (with Earl Gray, William Kelce
and others) published studies confirming that many of Peterson’s
findings could be reproduced in another strain of rat, and in
another species entirely, the Syrian hamster. The hamster is
known for being insensitive to dioxin’s effects, yet single
low-dose exposures of pregnant hamsters to dioxin produced nearly
a 60% reduction in sperm count in male offspring, plus other
important changes, such as a 23% reduction in the size of the
adrenal gland. [5]
This month, Earl Gray published a third study showing that a
single low dose of dioxin to pregnant rats could produce
hermaphroditic FEMALE offspring. Hermaphroditic means having
male and female sex organs simultaneously. [6] Other effects
included 30% reduction in the weight of the ovaries; shortened
reproductive life span; and increased incidence of cystic
hyperplasia of the endometrium (formation of multiple cysts in
the tissues lining the uterus).
There can no longer be any doubt that dioxin in very low
exposures during early development in mammals can dramatically
alter sexual development and behavior. The public health
implications are enormous.
This Congress seems in a mood to crucify EPA scientists for
reaching politically incorrect conclusions about dioxin. In an
earlier time (1632), a scientist like Galileo, threatened by
powerful religious zealots of his day, saved himself by
recanting. Will EPA scientists be forced to do the same?
                
                
                
                
    
–Peter Montague
===============
[1] Letter dated August 10, 1995, from Dana Rohrabacher to EPA
chief Carol Browner inviting her to testify September 13, 1995
before the House Energy and Environment Subcommittee of the
Committee on Science.
Descriptor terms: dioxin; toxicity; endocrine system; endocrine
disruptors; congress; public hearings; conservatives;
conservatism; hermaphroditism; homosexuality; sperm count; growth
and development; rats; hamsters; humans; morbidity; epa; u.s.
environmental protection agency; linda birnbaum; earl gray;
studies; janet raloff; dioxin reassessment; sab; paper industry;
corruption; science; science advisory board; environmental
hormones; fish; birds; wildlife; mammals; adrenal gland;
testicles; feminization; masculinization; tobacco; william kelce;
endometrium; galileo;