Save the Fetus - In a world awash in pollutants, what exactly is our obligation to protect the health of the unborn?
{Even tho' a number of studies document thimerosal's role in iatrogenic
neurotoxicity (eg, CDC 1999; 1), other toxins seem etiologically
significant - either as background factors that reduce an individual's
thimerosal-detox capability or as primary causes of neurologic problems
in at least some children. "Biomedical" aspects of dealing with
autism-spectrum disorders would seem to include identifying toxins and
toxic exposures, reducing toxic inputs, removing toxins from the
affected child, and rebuilding various physiological systems via
supplements, etc. -Teresa}
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Save the Fetus
In a world awash in pollutants, what exactly is our obligation to
protect the health of the unborn?
by Karen F. Schmidt
http://www.science-spirit.org/articles/newsdetail.cfm?item_id=527
When Kim Hooper gives a public talk about his work at the California
Department of Toxic Substances Control, he flashes a slide of his baby
granddaughter. “We’ve given her the best genes we can, but what about
her environment?” he asks the audience. “Already she’s had an early
experience far different than my own.” After all, Hooper points out, her
life in the womb began with exposure to myriad chemicals that weren’t
around sixty-five years ago.
It’s a reality that makes Hooper and many others nervous. Today, about
2,500 different chemicals are used in high volume, but basic information
about their potential effects on human development is still being
compiled. Many toxic villains have been unmasked in the last three
decades, including DDT, PCBs, dioxins, lead, mercury, and more recently,
phthalates (plasticizers) and PBDEs (flame retardants). As researchers
use new tools for measuring trace levels of contaminants in our bodies,
the issue of chemical safety is again in the spotlight. Studies using
“biomonitoring”—the testing of body tissues and fluids—are revealing
that we all harbor a cocktail of chemicals, some of which were banned
long ago.
Although it’s difficult to know whether the pollutants in our tissues
are causing harm, we do know where to look for the first signs of
trouble. “Fetuses are the population we think are the most sensitive to
chemical pollutants,” says Hooper. That’s because a small disturbance in
the highly choreographed process of development can have profound and
long-lasting effects on a baby, showing up immediately as birth defects
or later as subtle dysfunctions of the nervous, immune, and reproductive
systems. Scientists believe that environmental factors play a role in at
least three percent and as much as twenty-five percent of all
developmental defects in children, according to a National Academy of
Sciences report published in 2000.
Although the placenta was once thought to protect the fetus, researchers
now know that many harmful substances—drugs, alcohol, toxic byproducts
from cigarette smoke—pass through. Recent evidence suggests the
chemicals a pregnant woman is exposed to in her environment can and do
reach her fetus, Hooper says. Even chemicals encountered years ago can
come back to haunt; for instance, DDT and PCBs stored in fat tissues
slowly trickle into the bloodstream. But there are also plenty of new
contaminants to deal with as women of childbearing age ingest mercury in
their tuna fish sandwiches, breathe solvents wafting out of cosmetics,
and absorb particles coated with flame retardants while sitting on
treated couch cushions. The big question is: How much is reaching their
babies? As part of a study investigating fetal exposures to flame
retardants, Jane Williams, director of California Communities Against
Toxics, is recruiting 120 new mothers to give breast milk samples, which
she sends to Hooper’s lab group in Berkeley for analysis for PBDEs. The
chemicals— which have been added to everything from electronics to
drapery to vehicle interiors— have recently turned up in house dust,
river sediment, foods from the grocery store, and wildlife, as well as
people. Laboratory studies of mice found that low doses of PBDEs caused
offspring to suffer permanent defects in their ability to learn and
remember, and rats showed delayed sexual development. Since a fetus’s
exposure is generally the same as the mother’s, Williams says the early
breast milk samples will reveal the dose of PBDEs these California
babies got in the womb.
Such biomonitoring studies are finally possible due to advances in mass
spectroscopy that allow researchers to detect many different chemicals
in just a few drops of blood, urine, or breast milk. The analysis is
also cheaper than ever, so researchers can run experiments more often
and look for more chemicals. Indeed, the Centers for Disease Control and
Prevention now take blood and urine samples every two years from 2,500
adults across the country and test them for 116 chemical contaminants,
up from twentyseven in 1999. The third “National Report on Human
Exposure to Environmental Chemicals” is due to be released in June.
Still, the meaning of these measurements—often in parts per billion, or
the equivalent of one drop of water in an Olympic-size swimming
pool—remains an open question. As the CDC puts it, “The measurement of
an environmental chemical in a person’s blood or urine does not by
itself mean that the chemical causes disease.” Moreover, the CDC’s study
reveals nothing about sources of exposures. It was not designed to
identify geographic clusters of high exposure—near chemical waste dumps,
for example— nor was it meant to look for linkages to particular
products, such as hair dyes. The CDC’s goal is simply to get baseline
information about how much and what kinds of chemicals typically reside
in the bodies of a broad range of Americans, and to follow trends over
time, says John Osterloh, chief medical officer of the environmental
health laboratory at the CDC’s National Center for Environmental Health.
The CDC’s approach to biomonitoring gets a supportive nod from the
American Chemistry Council (ACC), a trade organization representing
ninety percent of U.S. chemical producers. Still, spokesman Chris
VandenHeuvel wonders what should be done with the CDC data. “We’re
concerned whenever someone jumps to the conclusion that finding very
small amounts of chemicals in the body is reason to worry,” he says.
“There is a level of anxiety that comes from publishing biomonitoring
results.”
Many environmental organizations—including the Environmental Working
Group, Greenpeace, and the World Wildlife Fund (WWF)—are indeed tapping
into this fear. For example, the WWF tested the blood of European
legislators while it lobbied them to support a European Union proposal
called REACH, a new system for regulating chemical safety. “Blood
testing is a good way to draw attention to what REACH is trying to
accomplish,” says Clifton Curtis, director of the WWF’s Global Toxics
program. “It shows directly that we are all contaminated— and so why
don’t we know more about these chemicals that are out there and entering
our bloodstreams through air, water, and food?”
Clearly, biomonitoring illustrates the need to investigate whether
environmental exposures are causing harm, and some researchers are doing
just this. In 1998, for instance, the Columbia University Center for
Children’s Environmental Health began examining the impacts of common
prenatal exposures on children. In one study of 314 infants, researchers
measured the levels of two household insecticides— chlorpyrifos and
diazinon— in blood drawn from the umbilical cord at birth. They found
that babies prenatally exposed to the highest combined level of
insecticides weighed a half-pound less on average and were significantly
shorter. Babies born after the EPA banned chlorpyrifos in December 2000
had markedly lower insecticide levels in cord blood, and the effect on
fetal growth disappeared. “The benefit of this regulatory action was
almost immediate,” says Frederica Perera, who directs the center and led
the study. Still, there is much more to be known. An encouraging sign
came last November, when the federal government launched a project to
track the health of 100,000 children from the womb to young adulthood.
The hope is that the National Children’s Study will answer critical
questions about whether children are being harmed by exposures to
pesticides, plastics, and heavy metals. In addition, researchers will
try to assess whether such environmental agents are contributing to
specific conditions, including autism, asthma, obesity, diabetes,
schizophrenia, and attention deficit hyperactivity disorder. The
ambitious study, however, comes with a $2.7 billion price tag—with
funding approved so far only to set up study centers and begin
recruiting participants—and it will take twenty-one years to complete.
In the meantime, there’s some disagreement over how to ensure that
children are protected from toxic exposures. Many environmental groups
want to apply the precautionary principle to chemical regulation.
Essentially, they would ask industry to prove that chemicals are safe,
rather than make citizens prove they are harmful. That’s the idea behind
the EU’s REACH proposal, which environmentalists believe could become a
global standard.
The ACC, however, prefers a cost-benefit approach to regulation, and is
fighting REACH. The group is working with U.S. embassy officials in
Europe to make the case that the new system would cost too much to
implement. ACC President and CEO Greg Lebedev says, “The world doesn’t
want or need European regulatory colonialism, and the EU’s trading
partners won’t buy a scheme that puts them at a competitive disadvantage
and is more complicated than a Rubik’s Cube.”
Still, calls to better protect fetuses and children from toxic exposures
resonate with many people—often for spiritual reasons. “There’s a sacred
bond between a mother and a child,” says Jane Williams. “Telling women
that the sanctity of that relationship is being tainted by the chemical
industry is very hard. They get really upset.”
Indeed, the urge to protect our offspring arises not just from biology,
but also from religion. Spiritual traditions are built on a respect for
life, says Daniel C. Maguire, a professor of religious ethics at
Marquette University. “Many religions view children as a symbol of the
most powerless people, as well as the glue that holds society together,”
he says. “As a principle of ethics, whatever is good for kids is good;
whatever is bad for kids is ungodly.”
Yet the same moral argument for protecting children can be extended to
anyone who unfairly bears the burden of pollution—be they African
Americans residing next to power plants or Pacific Islanders living with
radioactive fallout. “People should have an equal shot at a clean
environment,” says Manuel Pastor, founding director of the Center for
Justice, Tolerance, and Community at the University of California, Santa
Cruz.
Perhaps it’s no surprise then that Catholics, Jews, Protestants, and
Orthodox Christians came together two years ago to form the California
Interfaith Partnership for Children’s Health and the Environment. The
group spreads the word in religious communities about the impact of
synthetic chemicals on health, and gives people practical tips to reduce
exposure in homes, schools, and houses of worship, says director Suellen
Lowry. Members also encourage support for state legislation, such as one
bill requiring more detailed labeling of personal care products—
shampoos, nail polish, lotions—that contain chemicals linked to cancer
or birth defects. “As people of faith, we are called to care for the
vulnerable,” says Lowry, “and we ask our policymakers to heed this call,
too.”
http://www.science-spirit.org/openforum/forum1.cfm?room_id=2&from=roomlist
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1: Hornig M, Chian D, Lipkin WI.
Neurotoxic effects of postnatal thimerosal are mouse strain dependent.
Mol Psychiatry. 2004 Sep;9(9):833-45.
PMID: 15184908 [PubMed - indexed for MEDLINE]
2: Waly M, Olteanu H, Banerjee R, Choi SW, Mason JB, Parker BS, Sukumar
S, Shim
S, Sharma A, Benzecry JM, Power-Charnitsky VA, Deth RC.
Activation of methionine synthase by insulin-like growth factor-1 and
dopamine:
a target for neurodevelopmental toxins and thimerosal.
Mol Psychiatry. 2004 Apr;9(4):358-70.
PMID: 14745455 [PubMed - indexed for MEDLINE]
3: Baskin DS, Ngo H, Didenko VV.
Thimerosal induces DNA breaks, caspase-3 activation, membrane damage,
and cell
death in cultured human neurons and fibroblasts.
Toxicol Sci. 2003 Aug;74(2):361-8. Epub 2003 May 28.
PMID: 12773768 [PubMed - indexed for MEDLINE]
4. Jill James thimerosal study, published in Neurotoxicology but not yet
in Mudloon.
5. CDC's own findings (1999), especially in the context of the CDC's
intentional diluting of data; also peruse Safemind's critique of the
conflicts of interest within the IOM thimerosal-decree committee and
among the researchers whose studies whitewashed thimerosal. The IOM's
role is quite akin to that of the FDA, which serves pharmco interests
when adverse events are known and findings of adverse effects need to be
suppressed.
CDC thimerosal findings in 1999 - subsequent data dilution - Generation
Zero analysis is up on Safe Minds web-site
text synopsis
http://www.safeminds.org/Generation%20Zero%20Syn.pdf
full analysis, with charts
http://www.safeminds.org/Generation%20Zero%20Pres.pdf
6. A. Holmes, S. Cave, and J.M. El-Dahr. OPEN TRIAL OF CHELATION WITH
MES0-2,3-DIMERCAPTO SUCCINIC ACID (DMSA) AND LIPOIC ACID (LA) IN
CHILDREN WITH AUTISM. As submitted to IMFAR, June 2, 2001.
“Over 400 patients with autism are currently undergoing treatment for
removal of heavy metals. Patients are treated with DMSA alone at doses
of 10 mg/kg/dose 3 times a day for 3 days in a row (shorter duration
than lead protocol to decrease side effects) with 11 days "off" to allow
metals to re-equilibrate. After at least 2 rounds of DMSA alone, the
thiol antioxidant lipoic acid (hypothesized to aide in removal of heavy
metals across the BBB)is added to each dose of DMSA at 2-3mg/kg/dose. In
general, noticeable improvements in language, self-help skills,
interaction, and core autistic features are not seen until the patient
has been on DMSA with LA for 2-3 months.
“Of patients who have been on DMSA/LA for at least 4 months, these
results have been noted on general global assessment by parents,
teachers, and MDs: age 1-5yrs(n=40): marked improvement 35%, moderate
39%, slight 15%, none 11%; age 6-12yrs (n=25): marked 4%, moderate 28%,
slight 52%, none 16%; age 13-17 (n=16): moderate 6%, slight 68%, none
26%; age 18+ (n=4): slight 25%, none 75%. For example, a boy 5yr 5mo
scored in the average range on a one word expressive vocabulary test
10/00 and at age equivalent 8yr 2mo in 3/01 with no change in education
or medication other than starting DMSA/LA.
“The majority of children excrete mercury, lead, and other metals,
suggesting that there may be a generalized problem with metal
metabolism. Side effects include transient increases in hyperactivity,
self-stimulatory behavior, and loose stools. Younger children in
particular respond well to this therapy with significant improvement in
function.”
7. DMSA Chelation efficacy PPT presentation by Jane El-Dahr, M.D.
http://216.117.159.91/powerpoint/dan2002/El-Dahr.htm
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