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re: Morphological Deformations In Frogs
Hi Charlie -
Per your request for information on deformations in frogs, especially linked to
chemicals:
1) I'd look seriously at information on environmental estrogens, whose effects
include false hormone messages to animal fetuses in utero that can end up in
weird birth defects. You can start with "Our Stolen Future" by Theo Colburn, et
al, and otherwise do a search on environmental or xeno-estrogens. Lots of stuff
on it, and I know they've been looking at amphibians. NOTE: This has come to be
about more than estrogens, including information on the way that many hormones
that govern important processes are messed up by toxics, causing erroneous
messages and weird results.
For instance, Stolen Future p. 102 refers to Robert Stebbins, one of the world's
leading amphibian experts, professor emeritus of zoology at Univ Calif Berkeley,
who reviewed frog declines and saw patterns suggesting wind-borne contaminants
as a cause. The book says that Stebbins notes that frogs have a dramatic
metamorphisis from creatures that breathe water (tadpoles) to ones that breathe
air, and that this profound reorganization of their physiology is governed by
hormones and therefore vulnerable to synthetic chemicals that disrupt hormone
messages.
The book also gives information about Lou Gillette's studying the link between
toxics and alligators with birth defects in Florida (p.150+), including
multi-generational effects. They saw many effects here from hormonal disruption
(as the whole book discusses). A trigger for his insights came when hearing
that effects similar to DES were occurring in birds exposed to synthetic
chemicals.
I think you'd get interesting information from the book, as well as leads to the
top researchers working on this issue. Also, you can get information in many
related articles, including many where Colburn is quoted.
For instance, Newsweek 3/18/96 had a one page piece describing it (p.48) and
saying that Al Gore planned to talk about it, National Academy of Sciences is
studying the chemicals, and EPA is poised to. (NOTE: The New York Times has
some articles on this subject which I personally would ignore, as they have
shoddy research and are clearly inappropriately biased toward the pollutors.)
2) I am including some articles that might have some leads for you. (I put
"LEAD" on some that particularly stood out.) I've also forwarded your request
to other organizatios that might be able to help, and copied you on that
forward.
Hope this helps. Please let me know what you find out - I'd be very interested!
It's such an important topic, and certainly catching people's attention....
Patricia Dines
--- FORWARD --------------------------------------------------------------------
From: INTERNET:jablome@cdmnet.com
To: Patricia Dines, 73652,1202
To: Multiple recipients of list <dioxin-l@essential.org>
Date: Sun, Oct 20, 1996, 1:38 PM
Subject: 5-Legged Frog in Missouri
5-Legged Frog Crops Up In Missouri Pond
Sunday, October 20, 1996
By Tom Uhlenbrock
Of The St. Louis Post-Dispatch Staff
Brian Dampier was hunting frogs at a pond near
his school in Columbia when he made a catch
that thrust Missouri into the midst of a disturbing
wildlife phenomenon.
"I grabbed really fast and got a handful of mud
and a frog," said the seventh-grader. "When I
cleaned the mud off, I saw the frog had five legs.
I thought, `Whoa, what's wrong here?' "
Brian took his catch to Mike Bielski, the science
teacher at Gentry Middle School. Bielski had
heard that similarly deformed frogs were being
found elsewhere and that pesticides or other
sources of environmental pollution were
suspected as the potential cause.
Bielski called state herpetologist Tom Johnson,
who visited Columbia Wednesday to inspect
what Dampier had found, and Missouri officially
joined the ranks of states, most of them in the
Midwest, where ponds were producing frogs with deformities.
Although they haven't determined what's causing
the deformities, researchers say concern should
be great. Amphibians - because their skin is
permeable and permits toxins to invade - can be
the first detectors of problems in a biological system.
"Amphibians are very good indicators of the
health of the environment," Johnson said. "This is
not a quirk. It's something we need to look at seriously."
The first report of deformed frogs came last
year, as Cindy Reinitz led a nature-studies class
on a field trip in the heart of Minnesota's farm
country. The class walked by a pond, and the
boys began to catch frogs.
Some of the frogs had missing hind legs, others
had too many legs or no legs at all. Others had a single eye.
The closer the class got to the pond, "the more
grotesque the deformities were, probably
because those frogs were unable to move away
from the water," Reinitz said. "One girl pulled out
a notebook and said, `We need to record data.' "
The class was on its way to study a woodland.
But the students' initial disgust at the misshapen
frogs soon turned to fascination, and the
Minnesota New Country School Frog Project was born.
Biologists long have reported that populations of
certain species of amphibians are dwindling, but
the field trip last year was the first documentation
of a pondful of misshapen frogs.
The school project set up a hot line and a page
on the Internet, seeking other reports of deformed frogs.
So far, deformed frogs have been found at 174
sites in Minnesota - and in the states of
Wisconsin, Vermont, South Dakota, Ohio,
Alabama and Michigan and the province of
Quebec. Iowa is looking into scattered reports;
Illinois has a single report of a frog with multiple legs.
Missouri had no confirmed reports until last week.
What's Happening?
The deformities are found in several frog
species, including the northern leopard frog,
which is common to most of the Midwest. Brian
Dampier's catch was an immature green frog.
Cricket frogs found in the pond appeared healthy.
LEAD A recent conference in Duluth, Minn., brought
the country's biologists together to discuss
theories on what's happening with the frogs.
Many causes are blamed for the disappearance
of amphibian species. The most prominent are
the destruction of wetlands and other habitats
and the introduction of new predators, such as
bullfrogs in the West and trout in mountain lakes.
Also suspected are atmospheric changes, such
as acid rain, the depletion of the Earth's upper
ozone layer and the infiltration of more harmful
ultraviolet rays from the sun.
But those culprits are thought to cause death, not deformity.
Biologists at the conference offered a variety of
possibilities for the deformities, ranging from
parasites to pesticides to heavy metals. The
LEAD Environmental Protection Agency is planning its own study.
Earlier studies on animals, Johnson noted, have
found that some pesticides and other chemicals
interfere with the development of an embryo,
causing deformities and sexual dysfunction in the
fetus. What happens in animals could happen in humans, he said.
Frogs As Barometers
LEAD The Minnesota Legislature allocated $123,000
for a study of the frogs by the state Pollution
Control Agency and the University of Minnesota.
"So far, they haven't found anything that jumps
out," said Ralph Pribble of the agency. "No definitive trends."
The research has looked at pesticides and
herbicides used in the area, as well as soil and
water chemistry and history of land use.
Pribble said the research had drawn interest
from all over the world, where frogs may not be
deformed, but are disappearing, along with other
amphibian species.
"There's been a lot of research on the population
declines, but nobody had seen deformities on
this scale until last year," he said. "They think of
this as a new wrinkle in the ongoing stress that
frogs have been under worldwide.
"Our staff is saying it ultimately may wind up
being a piece of that puzzle."
Val Beasley, a professor at the University of
Illinois who attended the Duluth conference, said
publicity over the plight of the frogs could bring
attention to a general over-taxing of the Earth's resources.
"Every place there's a wet spot, we're putting in
a tile and draining it," Beasley said. "It's immoral
to push the land that hard. It's not part of
sustainable agriculture."
Reinitz, the Minnesota school teacher, made a similar argument.
She referred to a children's book, "Kermit's
Guide to Life in the '90s." In the final pages,
Kermit explains that frogs in today's environment
are like the canaries used to warn gold miners
when the air was bad. When the canary died, it
was time to get out.
"You know," Kermit says, "frogs turn out to be
the barometers of the Earth. When we go, so
does the neighborhood."
LEAD Pictures at http://www.mncs.k12.mn.us/frog/picts.html
--- FORWARD --------------------------------------------------------------------
From: jill davies, INTERNET:nox2228@montana.com
To: Patricia Dines, 73652,1202
To: Multiple recipients of list <dioxin-l@essential.org>
Date: Mon, Oct 7, 1996, 8:58 AM
Subject: re/ last straw
excerpt from
THE ENVIRONMENTAL NEWS DAILY
*9 FROGS: DEFORMED AMPHIBIANS RAISE CONCERNS IN MN
Since 8/95, researchers have found deformed frogs at more
than 100 sites in 54 of Minnesota's 87 counties, prompting the US
EPA to covene a meeting of scientists in Duluth, MN, to discuss
the phenomenon, reports the WASH. POST. EPA's Joe Tietgem:
"It's certainly safe to say it's an environmental problem."
This summer, a research team comprised of U. of Minnesota
researchers and Minnesota Pollution Control Agency officials
discovered "hideously deformed" frogs with missing legs, extra
legs, misshapen legs and missing eyes.
Early evidence on what is causing the deformities points to
something in the water where the frogs breed and develop. But
two theories are "receiving the most scrutiny." One is that the
frogs have become infested with a naturally occurring parasite,
while a second theory points to some kind of chemical pollutant.
Robert McKinnell, a geneticist at the U. of Minnesota, <LEAD> said
frogs serve as a "sentinel species," because many of their
metabolic functions are similar to humans. McKinnell: "Now the
whole state appears to be affected. We should be alarmed"
(William Souder, WASH. POST, 9/30).
--- FORWARD --------------------------------------------------------------------
=======================Electronic Edition========================
. RACHEL'S ENVIRONMENT & HEALTH WEEKLY #515 .
. ---October 10, 1996--- .
<contact info>
=================================================================
FROGS GIVE WARNING
The WASHINGTON POST reported September 30 that frogs with severe
birth defects have been discovered during the past two summers in
54 of Minnesota's 87 counties, across Wisconsin, and up into
the St. Lawrence River Valley in Quebec, Canada.[1]
According to the POST, herpetologists (scientists who study
amphibians and reptiles) have reported finding frogs with missing
legs, extra legs, misshapen legs, paralyzed legs that stuck out
from the body at odd places, legs that were webbed together with
extra skin, legs that were fused to the body, and legs that split
into two half-way down. They have also found frogs with missing
eyes. One one-eyed frog had a second eye growing inside its throat.
Robert McKinnell, a geneticist and cancer researcher at
University of Minnesota (St. Paul, Minn.), said he initially
thought the reports of deformed frogs didn't amount to much.
Frogs have a small number of birth defects naturally. Then
McKinnell began visiting various sites in Minnesota and finding a
large proportion of deformed frogs (96% at one site). Now he
says, "The whole state appears to be affected. We should be alarmed."
Frogs are amphibians. They spend their lives both in the water
and on dry land. Beginning life as eggs floating on the surface
of still waters, they develop into swimming tadpoles, eventually
changing completely, becoming frogs. These major changes in form
occur under the control of hormones, which are chemical
messengers that travel throughout the organism, turning on and
off bodily processes.
Since August, 1995, when the first deformed frogs were found in
south-central Minnesota, researchers have been searching for the
cause, without success. So far, they say, they believe inherited
genetic mutations are not involved. This would mean the
deformities are being caused by something that affects the frogs
during early life, when they are eggs or tadpoles. Judy Helgen,
the research scientist who is leading the investigation on behalf
of the Minnesota Pollution Control Agency says she thinks the
cause will eventually be discovered to be chemicals of some kind,
though it could take several years to pin it down.
Little research has been done to study the effects of
environmental chemicals on amphibians. It seems that most
researchers have been focused on confirming or refuting the
reported worldwide decline in populations of frogs, toads and
salamanders. (See REHW #246, #380.) Indeed, some of the
recently-reported declines are large, mysterious and compelling.
For example, a study published in April compared amphibian
populations in 1915 vs. 1992 in Yosemite Park in California. The
study found that seven kinds of amphibians are declining in
numbers, and three have disappeared entirely from Yosemite.[2]
Yosemite isn't truly pristine because of air pollution from
distant cities, but it is about as clean an environment as you
can find in the lower 48 states. Dr. Ronald Heyer, a researcher
with the Smithsonian Institution (and chair of the Declining
Amphibian Populations Task Force [DAPTF] of the World
Conservation Union's Species Survival Commission) says, "It's
kind of chilling in its effect. Here we have what we consider to
be a relatively protected place, and amphibian declines are
occurring even there."[3]
Amphibians are particularly sensitive to chemical pollution
because they live both in water and on land. Furthermore, they
breathe through their skin. Some researchers suspect that toxic
heavy metals and pesticides building up in aquatic food chains,
plus serious air pollution, may be what's killing some frogs,
toads, and salamanders.
Many researchers now believe that increased ultraviolet radiation
may be affecting frogs' eggs, which float on the surface of the
water, absorbing sunlight.
Despite scientists' intense focus on population decline and
extinction, recent studies have begun to try to find the causes
of birth defects in frogs in Minnesota and Wisconsin.
At the Great Lakes Declining Amphibians Conference in Milwaukee
March 30, Robin E. Jung from the University of Wisconsin at
Madison described new studies indicating that leopard frogs
collected at a PCB-contaminated site on the Fox River in
Wisconsin had more spinal deformities than frogs collected at a
cleaner Green Bay site.[4]
A few previous studies had linked frog deformities to
pesticides.[5,6,7] <LEAD> Still, to date, remarkably little testing has
been done to see if environmental chemicals cause birth defectsin frogs.
On the other hand, a recent large study has linked birth defects
in humans to pesticide use in Minnesota.[8] <LEAD>
Researchers from the University of Minnesota and the U.S.
Environmental Protection Agency (EPA) linked the Minnesota birth
registry for the years 1989-1992 with information about pesticide
use across the state.
Two pictures emerged: (1) the birth defect rate for all birth
defects was significantly increased in children born to private
pesticide appliers, compared to the general population; and (2)
births in the general population of western Minnesota (the area
of highest use of pesticides) showed a significant increase in
birth defects, compared to the rest of the state. This second
effect was most pronounced among children conceived during the spring.
Researchers from the University of Minnesota and the U.S.
Environmental Protection Agency (EPA) examined 210,723 birth
records in the state of Minnesota covering the four-year period 1989-1992.
They first focused on 4935 children born to state-licensed
private pesticide appliers in Minnesota (of which there are
34,772). They found statistically significant elevations in the
occurrence of all birth defects taken together, as well as in
specific subcategories of birth defects: circulatory/respiratory
defects, musculoskeletal defects; and urogenital defects.
Secondly, they focused on the general public. They divided the
state into two regions, agricultural and non-agricultural. They
found that "data show that families residing in predominantly
agricultural regions of Minnesota are more likely to have
children with birth anomalies." This finding was statistically
significant.
Third, they subdivided the agricultural part of Minnesota into
smaller areas, based on the kinds of crops that dominate. They
then examined 12 specific herbicides. The most consistent
results were obtained for the herbicides 2,4-D and MCPA
[4-chloro-2-methylphenoxyacetic acid]. Areas designated by the
Minnesota Department of Agriculture as "high use" areas for these
herbicides, when compared against "low use" areas, had
significantly increased birth defects (about an 86% increase) for
defects of the central nervous system, circulatory/respiratory,
urogenital, and musculoskeletal systems, as well as a 51%
increase for all birth defects combined.
In regions where chlorophenoxy herbicides are in use (such as
2,4-D and MCPA), infants conceived in the spring had about 30%
more birth defects than infants conceived in other seasons. This
effect was not noted in regions reporting low or no use of
chlorophenoxy herbicides.
The researchers reported that in the five counties with the
highest reported use of 2,4-D herbicide, registered appliers gave
birth to only half as many children in 1990 as did the general
population. The researchers noted that this finding was
consistent with an earlier study showing that 2,4-D is toxic to
sperm in pesticide appliers.
Finally, the researchers observed that the sex ratio of live
births is usually in the range of 104 to 107 males born for each
100 females. In Minnesota in 1989-1992, the sex ratio was 105
males to 100 females for normal births and 138 males to 100
females for births with defects. The researchers say they believe
something in the pesticides used in Minnesota is suppressing the
births of female children or favoring the births of males.
Interestingly, a recent study examined the sex ratio among the
first 74 children born to parents exposed to dioxin during an
industrial accident at Seveso, Italy.[9] Among highly
dioxin-exposed parents, female children outnumbered males (26
males vs. 48 females, a ratio of 54 males for every 100 females).
This skewed sex ratio lasted for 8 years after the Seveso
accident, then returned to normal.
Children may be the victims of pesticides and dioxin, yet they
still offer hope. The first deformed frogs were discovered in
Minnesota in August 1995 by middle school children --10 year olds
--on a field trip to a farm.[1] After they noticed a one-legged
frog, they started collecting others. In a morning they
collected 22 frogs, 11 of them with major birth defects. "I
think the kids got kind of scared," says their teacher, Cindy
Reinitz. "They immediately started asking me what the cancer rate
was in the area." Now that's an impressive question from a group
of 10 year olds. When all our health officials and corporate
CEOs are as alert, insightful and concerned as those children,
we'll no longer have to rely on frogs to give us warning.
--Peter Montague
(National Writers Union, UAW Local 1981/AFL-CIO)
===============
[1] William Souder, "Hundreds of Deformed Frogs Pose
Environmental Warning," WASHINGTON POST September 30, 1996, pg.
A1.
[2] C.A. Drost and G.M. Fellers, "Collapse of a Regional Frog
Fauna in the Yosemite Area of the California Sierra Nevada,"
CONSERVATION BIOLOGY Vol. 10 No. 2 (1996), pgs. 414-425.
[3] Carol Kaesuk Yoon, "Eerie Quiet of Frogs and Toads Isn't Part
of Normal Cycle, Study Says," NEW YORK TIMES April 30, 1996, pg.C4.
[4] Robin E. Jung and others, "Amphibian Ecotoxicology in Green
Bay, Wisconsin: are toxicants influencing amphibian
distributions?" a paper presented at the Great Lakes Declining
Amphibians Conference March 30, 1996, at the Milwaukee
[Wisconsin] Public Museum. An abstract of this paper is available
on the world wide web:
http://www.mei.com/other/mpm/collect/daptf.html.
[5] Gerald S. Schuytema and others, "Teratogenesis, Toxicity and
Bioconcentration in Frogs Exposed to Dieldrin," ARCHIVES OF
ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY Vol. 21 (1991), pgs.
332-350. Schuytema reports that he could produce "gross spinal
deformities" by exposing African clawed frogs to 1.3 parts per
billion (ppb) of dieldrin in water and in bullfrogs at 25.4 ppb.
See pg. 341.
[6] G.S. Schuytema and others, "Toxicity of Guthion and Guthion
2S to XENOPUS LAEVIS Embryos," ARCHIVES OF ENVIRONMENTAL
CONTAMINATION AND TOXICOLOGY, Vol. 27 No. 2 (August 1994), pgs.
250-255. In this study, Schuytema says he believes it is the
"inert" ingredients in the pesticides that cause the toxicity of
Guthion (an organophosphate) to frogs. So-called "inerts" are
secret ingredients in pesticides; many "inerts" are not inert at
all, but are chemically active and toxic. By federal law the
public (including scientific researchers) are prohibited from
knowing what "inert ingredients" have been added to a pesticide.
[7] R. Alvarez and others, "Skeletal Malformations Induced by the
Insecticides ZZ-Aphox and Folidol During Larval Development of
RANA PEREZI," ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND
TOXICOLOGY Vol. 28 (1995), pgs. 349-356.
[8] Vincent F. Garry and others, "Pesticide Appliers, Biocides,
and Birth Defects in Rural Minnesota," ENVIRONMENTAL HEALTH
PERSPECTIVES Vol. 104, No. 4 (April, 1996), pgs. 394-399.
[9] Paolo Mocarelli, Paolo Brambilla, Pier Mario Gerthoux, Donald
G. Patterson, Jr., Larry L. Needham, "Change in Sex Ratio with
Exposure to Dioxin," THE LANCET Vol. 348 No. 9024 (August 10,
1996), pg. 409.
Descriptor terms: frogs; amphibians; wildlife; birth defects;
teratogens; pesticides; pcbs; species loss; yosemite; california;
air pollution; ultraviolet radiation; fox river; wi; mn; green
bay; children; dioxin; sex ratio; seveso; italy; extinction;
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THIS INFORMATION PROVIDED BY: Patricia Dines
73652.1202@compuserve.com
Specializing in educating and empowering citizen action on toxics issues,
through teaching, giving talks, and writing articles, classes, booklets, and
other materials.
Please contact me for more information on my services, how it might support your
goals, to make a financial contribution so that I can continue my work (often
done for free), or to alert me to potential clients who might be assisted by my
services.
Thanks!
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