long article about Lead
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| Wed, 07-26-2006 - 11:16am |
How Lead Violates the Brain
In their 1998 investigation into lead's effects on the brains of children,
Israeli researchers found that, for starters, lead disrupts the main
structural components of the blood-brain barrier, (by injuring the glial
brain cells that surround and protect neurons and by damaging the
capillaries that keep toxins out of the brain).
Once in the brain, lead-induced damage occurs primarily in the prefrontal
cerebral cortex, cerebellum, and hippocampus. There it adversely affects
many biological activities at the molecular, cellular, and intracellular
levels.
Writing in the July 1998 issue of Brain Research, neurologists at Shaare
Zedek Medical Center in Jerusalem reported that lead interferes with the
action of calcium and with the neurotransmitter systems that are crucial to
regulating emotional response, memory, and learning.
They found a direct link between low-level long-term exposure to lead and
deficits in cognitive performance and behavior in childhood through
adolescence. They also concluded that "there is no threshold below which
lead remains without effect on the central nervous system."
Since learning requires the remodeling of the brain's synapses — the spaces
between neurons where information is exchanged — lead may specifically
affect synaptic transmission. In 1999, neurologists at Johns Hopkins
University School of Public Health proposed that the learning deficits
caused by lead are due to its disruption of processes regulated by calcium
(protein kinase C) at the synapse.
Lead and Dementia
Animal studies done in the 1980s showed that lead inhibits myelination and
microtubule assembly in the brain, as well as caused the formation of fibers
and "aggregates of amorphous material." This suggests that lead may be
involved in senile dementia, although little research has been done in this
area.
The November 1998 issue of the journal Epidemiology published a report
titled, "Is chronic low-level lead exposure in early life an etiologic
factor in Alzheimer's disease?" According to Dr. Prince at the London School
of Hygiene and Tropical Medicine and the Institute of Psychiatry, England:
"Few environmental risk factors for Alzheimer's disease have been
identified. This lack of information may reflect the fact that salient
factors affect most of the population in developed countries. Furthermore,
the critical period of exposure may be earlier than hitherto suspected,
during the first years of life, as the brain differentiates and develops.
Exposure to lead at levels lower than those associated with evident toxicity
causes mild intellectual impairment in childhood. I hypothesize that this
may be one of the childhood exposures that also confers an additional risk
for the onset of Alzheimer's disease."
The Prefrontal Cortex and Your Moral Imperative
Your prefrontal cortex is the most human part of your brain. One of the
things it allows you do is to see things from a different point of view, to
walk in someone else's shoes — in a word, empathy. Since the 1980s,
scientists have correlated damage to the prefrontal cortex with psychopathic
behavior and the inability to make morally and socially acceptable
decisions.
Swedish researchers have found that the prefrontal cortex is precisely the
area of the brain that is is impaired in murderers, rapists, and other
violent criminals who repeatedly re-offend. At the November 1999 annual
meeting of the Society for Neuroscience, Asa Bergvall and her colleagues
from the University in Sweden presented findings on their study of violent
offenders.
The results were quite startling."The violent offenders are like the
controls in every task but one, which taps prefrontal function," says
Bergvall. "In that, it was as if they were retarded." They had an impaired
ability to shift their attention in order to view the world in a different
way — a function linked to the lateral prefrontal cortex. Other, higher
order executive functions of their prefrontal cortex appeared to be
unimpaired.
Childhood Damage to the Prefrontal Cortex is the Worst
In a related presentation at the Society for Neuroscience meeting,
researchers reported that children who experience early prefrontal damage
never completely develop social or moral reasoning. Even on an intellectual
level they cannot refer to such behavior because they have little concept of
it.
In contrast, individuals with adult-acquired damage are usually aware of
what proper social and moral behavior should be. However, they are unable to
act upon it. Even though they have an intellectual memory of learned moral
conduct, they cannot apply such behaviors.
A study at University of Iowa College of Medicine, published in the November
1999 Nature Neuroscience, reports on two cases of early brain damage to the
prefrontal cortex, in which the patients as adults showed the same two
distinctive features: an almost total lack of guilt and an inability to plan
for the future — but were normal in almost every other type of mental
ability.
The patients had problems with violence and "resemble psychopathic
individuals, who are characterized by high levels of aggression and
antisocial behavior performed without guilt or empathy for their victims,"
wrote Raymond Dolan of Institute of Neurology in London in an editorial that
accompanied the research. Their brains were just not capable of acquiring
social and moral knowledge even at a normal level.
Unlike other areas of the brain, the prefrontal cortex is not particularly
plastic. If the area responsible for moral and social awareness is damaged
in childhood, it can never develop. Dolan suggested that this understanding
of the brain will require a reappraisal of the way society deals with
criminal behavior, because "problems with moral and social behavior may be
rooted in physical problems in the brain."
As New York physician Dr. Charles Gant describes it: In evolutionary terms
the prefrontal cortex is "the last part of the human brain to develop and is
one of the first parts to lose its function when there is a generalized
stress or injury to the central nervous system. Because this recent brain
structure has not had the benefit of millions of extra years of 'road
testing,' that the older, more rugged parts of the brain have had, it is
more vulnerable to modern-era stress, neurotoxins, and nutritional
deficiencies."
Our Old Enemy, Lead, has a New Ally
Important ongoing research has revealed a widespread, serious risk co-factor
for lead poisoning. And it is reminiscent of an incident described by
Benjamin Franklin in his letter:
"But I have been told of a case in Europe, I forget the Place, where a whole
Family was afflicted with what we call Dry Bellyache, or Colica Pictonum, by
drinking Rain Water. It was at a Country-Seat, which being situated too high
to have the Advantage of a Well, was supply'd with Water from a Tank, which
received the Water from the leaded Roofs. This had been drunk several Years
without Mischief; but some young Trees planted near the House growing up
above the Roof, and shedding the Leaves upon it, it was suppos'd that an
Acid in those Leaves had corroded the Lead they cover'd and furnished the
Water of that with its baneful Particles and Qualities."
Today's acid rain is not the only factor increasing lead contamination.
Researchers at Dartmouth University found that certain chemicals being added
to our drinking water are magnifying the uptake of lead and other toxic
metals into the body and brain. Analyzing a major survey of more than
280,000 Massachusetts children, the team headed by Prof. Roger D. Masters
has identified corrosive chemicals widely used in the fluoridation of public
water supplies that apparently increase children's absorption of lead.
Fluoridation Increases Lead Uptake
The culprits are silicofluorides — fluosilicic acid and sodium
silicofluoride — the chemicals used in more than 90% of America's
fluoridated drinking water systems. In their study published in the October
1999 International Journal of Environmental Studies, the Dartmouth
researchers show that children's blood lead is significantly higher in
Massachusetts communities using silicofluorides than in towns where water is
treated with sodium fluoride or not fluoridated at all. Compared to a
matched group of 30 towns that do not use silicofluorides, children in 30
communities that use these chemicals were over twice as likely to have more
than 10 ug/dL of lead in their blood.
"Silicofluorides are largely untested," Professor Masters explains.
"Virtually all research on fluoridation safety has focused on sodium
fluoride, even though the studies in the 1930s showed important biological
differences between these chemicals."
Since completing the Massachusetts study, the Dartmouth group further
confirmed the link between silicofluorides and elevated blood-lead levels —
based on data from rural counties in six additional states, as well as from
a survey of more than 120,000 children in New York towns and from the Third
National Health and Nutrition Evaluation Survey (NHANES III).
History Repeats Itself
Just like the acidic leaves that leeched lead from the paint on that 18th
century roof, fluosilicic acid leaches lead from plumbing. This was
graphically demonstrated in two communities that stopped fluoridating their
water systems. Their lead levels dropped significantly.
During a 1992 drought in Tacoma, Washington, they temporarily stopped
fluoridating their water and lead levels dropped from 32 ppb (parts per
billion) to 17 ppb. When Thurmont, Maryland stopped fluoridating their
drinking water in 1994, the lead level in homes dropped from 30 ppb to 7
ppb. (The EPA's Maximum Contaminant Level is 15 ppb.)
More than 98% of U.S. homes have lead in their plumbing systems. It comes
from lead pipes, or copper pipes connected by lead solder, and from brass
faucets, which also contain lead . Most chrome plated faucets are made of
brass which is permitted to contain as much as 8% lead.
Poisoning the Well — Lead, Drugs, and Violence
According to Prof. Masters, who heads the Dartmouth Foundation for
Neuroscience and Society, "Through one of several plausible mechanisms, SiF
treated water can increase the transport of heavy metals
across the gut-blood and blood-brain barriers, increasing rates of toxic
uptake and behavioral disfunction."
On Sept. 2, 1999 at the Annual Conference of the Association for Politics
and the Life Sciences, Prof. Masters gave the Plenary Address: "Poisoning
the Well: Neurotoxic Metals, Water Treatment, and Human Behavior." He said
the problem is especially serious because lead poisoning is associated with
higher rates of learning disabilities, hyperactivity, substance abuse, and
crime. Children who have been poisoned by lead are less able to handle
stress and are more prone to violent outbursts.
Silicofluorides and Violence
Heavy metals damage neurons and "compromise normal brain development and
neurotransmitter function, leading to long-term deficits in learning and
social behavior," says Masters. Lead blocks the action of calcium atoms in
the synthesis of serotonin and dopamine, neurotransmitters essential to
normal impulse control and the suppression of violent behavior.
Where silicofluorides were used to fluoridate water, risk-ratios for blood
lead over 10 ug/dL are from 1.25 to 2.5 — more than doubled. Silicofluorides
are thus ultimately responsible for more aggressive behavior among people
who consume fluoridated water — including the soft drinks, juices, and foods
made with fluoridated water — and whose diets are lacking in calcium.
After an analysis of 129 rural communities in Georgia, Masters also found
that "communities using silicofluorides also report higher rates of learning
disabilities, ADHD, violent crime, and criminals who were using cocaine at
the time of arrest." This makes sense because lead depresses dopamine levels
in the brain, and cocaine addiction is associated with low levels of
dopamine.
An Old Story — Rome
Throughout history lead has been intimately related to plumbing. On the
periodic table of elements, the symbol for lead is "Pb" — short for
plumbum — the Latin word for plumbing. In ancient Italy magnificent
aqueducts carried water from the mountains, supplying the people of Rome
with 220 million gallons of water per day. Inside the city, water was
distributed by lead pipes. The diameter of the pipe determined the cost of
water, which flowed continuously. There were no faucets.
The Romans also used lead to halt the fermentation of wines and to preserve
food. Their drinking vessels and cookware were coated with lead glazes.
(Ceramics are still a source of lead exposure in modern times.)
Evidence still exists of the Romans' huge lead mining operations two
millennia ago in southwestern Spain. Researchers have detected lead
concentrations in core samples taken from Greenland's ice, evidence of
large-scale pollution of Earth's atmosphere that peaked between 150 B.C. and
50 A.D., the height of Roman mining activity. "Lead pollution levels during
the Roman era were about four times greater than natural background levels
of lead but were still low by modern standards. Between the 1930s and 1970s,
the lead concentration in the ice was 25 to 50-times higher than during
Roman times, due in large part to leaded gasoline."
Dr. Herbert L. Needleman, a leading researcher on the effects of low-level
lead exposure, notes that the "increase in psychiatric disturbance in upper
class Romans may have been related to lead exposure from plumbing and wine
additives and thus was in part responsible for the decline of Rome."
Tin cans sealed with lead were once a major source of contamination. In the
1840s a famous expedition trying to find the Northwest Passage became lost.
More than 140 years later their bodies were finally found. The entire group
had been poisoned to death by the lead in their cans of food. First,
sleeplessness and irrational behavior overtook them. Then death came when
the lead blocked the enzyme responsible for hemoglobin production, and their
kidneys failed.
Sources of Lead Exposure this Century
In "The Story of Lead," Peter Montague reports: "The period of greatest lead
use was 1945-1971, after which it began to decline. In those years, 165,000
to 275,000 tons of lead dust spewed from the exhaust pipes of American
automobiles each year. Americans born during these years have 300 to 1000
times as much lead in their bodies as pre-Columbian indigenous people had.
Thus the generation of decision-makers in power today — in government and in
corporations — is made up of people who are suffering mental irritability
and dysfunction as a result of severe chronic lead insult. Reviewing the
history of the past 25 years, it seems clear that the nation and the world
have already paid a terrible price for their irritability and dysfunction.
Leadership by the most lead-damaged (those born around 1970) lies just
ahead."
The CDCP's 1998 study reported that the average concentration of lead in all
20 million American preschoolers was 2.7 ug/dL, or 43 times as high as the
natural background. The 10 ug/dL now established as "safe" for children
is 625 times greater than the average lead level in the bodies of the
pre-Columbian inhabitants of North America.
The EPA permits our drinking water to have 15 ppb, but according to one of
their own studies: "Drinking water supplied to 30 million people in 819
cities contains unhealthy levels of lead."
"Cover the Earth"
In the United States, paint is now the chief source of the lead that poisons
children. Leaded paint is still very common in older houses. More than 80%
of U.S. housing built before 1980 contain some lead-based paints. In
particular, white paint used to be made with lead carbonate and yellow paint
from lead chromate.
Although lead and mercury, another toxic metal, are no longer allowed in
paint, other chemicals continue their legacy. According to their labels,
certain paints contain solvents that "can cause permanent brain and nervous
system damage." For some strange reason, paint seems to be the delivery
system of choice for brain damage. (Will future archeologists be baffled by
a society whose walls were more vibrant than its brain cells?)
In October 1999, the state of Rhode Island sued eight of the nation's
largest paint companies for marketing lead-based paints that are poisoning
thousands of children. Atty. Gen. Sheldon Whitehouse said that nearly 20% of
Rhode Island children entering kindergarten had elevated lead levels, and
"it's time to force those who made the mess to clean it up."
According to a report in The Providence Journal (Oct. 16), Whitehouse says
the paint industry knew about the dangers of lead since the 1930s. He quotes
industry officials in the 1950s who referred to lead poisoning as "mainly a
problem in the slums and voicing more concerns over bad publicity than over
the victims." What's worse, "paint company publicity extolled the health
benefits and safety of lead paints."
Another source of lead is vinyl mini-blinds made in Asia and Mexico.
Laboratory tests show that when these particular mini-blinds deteriorate,
their dust contains high levels of lead that can end up on children's hands
and in their mouths. Also, candles with lead in their wicks have been shown
to produce unhealthy levels of lead in the air for many hours — even after
the candle is no longer burning.
Environmental lead exposure from industrial pollution and lead residues in
soil further add to the accumulating burden of lead in the body and brain.
Getting the Lead Out
Oral or intravenous chelation therapy is the primary means for mobilizing
lead and other heavy metals from the body, according to Dr. Walter J.
Crinnion, a naturopathic physician who teaches environmental toxicity at
Bastyr University in Seattle. Since 1987 he has operated the most
comprehensive cleansing protocol in the nation and has found that "Diets
high in the pectins and foods high in sulfur containing amino acids
(methionine, cysteine) such as onions, garlic and beans can help. Sweating
also helps to some extent."
And, based on the 1999 Dartmouth study, it would be wise to avoid water
treated with caustic fluoride compounds.
Ending the Violence of Lead
The time has come to acknowledge the real dangers of lead contamination.
Lead threatens civility and compromises critical thinking — at the very time
when these qualities are needed the most. Lead impairs our ability to
distinguish between primitive impulse and intelligent action. Furthermore,
its role in our epidemic of suicide and domestic violence has yet to be
investigated.
Humankind has barely ascended from the gene pool of thoughtlessness where
reaction is the rule, and only by a slender thread does our humanity hang.
This century, the human brain is being challenged by concentrations of lead
and other heavy metals far beyond its evolutionary experience. The toxins we
have loosed into the environment are corrosive to cognition and
consciousness. By attacking the headquarters of our humanity, our priceless
prefrontal cortex, they disintegrate our thin veneer of civilization —
shredding that slender thread.
"This, my dear Friend, is all I can at present recollect on the Subject. You
will see by it, that the Opinion of this mischievous Effort from Lead is at
least above Sixty Years old; and you will observe with Concern how long a
useful Truth may be known and exist, before it is generally receiv'd and
practis'd on.
I am, ever, yours most affectionately, B. Franklin"

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Edited 2/19/2008 1:16 pm ET by littleroses
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Edited 2/19/2008 1:15 pm ET by littleroses
Once again you guys confuse me, lol. But I love the info.
I have to print this up and read it with a highlighter so I actually understand it. I have a pretty good idea what lead does and how it may have had a part in affecting my kids. What I really need to look for now is if chelation will help now.
Like DH says, once heavy metals are in your body they stay and continue to do damage. So getting rid of what is there is a good idea. I am not sure we can reverse any damage already done however.
I do wonder now if this is part of the reason why Mike has continuously gotten more symptomatic with age (and not just a natural progression) as well as perhaps the cause of Cait's seizures.
LR, I really have to figure out everything you have written and what it means to me. If I can get the right zincs, calcium and all that going on it may help. I just have no idea where to start with my kids with that.
Renee