Heavy
metals are a well-known cause of environmental
pollution and of serious
hazard to human health. The effects of their actions are
not immediate, but show up after many years or decades. Due to their wide usage
in many industrial branches they are present everywhere in the air, water
and soil. Food contaminant by heavy elements is hard to avoid and it is a
result of environmental contamination by dusts, industrial gases, sewage,
waste and coal burning processes. The content of heavy metals in the
environment is quite diverse and their harmful action depends on the type
of element, the chemical form of their occurrence and the state of
organism's nutrition. One of the very toxic and also very frequently used
heavy metal is mercury. Exposure to mercury can cause
immune, sensory,
neurological, motor and behavioral dysfunctions.
Fish consumption is a main source of mercury intake by Americans.
Mercury finds itself into waterways, mostly through the burning of fossil fuels
like coal, where bacteria convert it to toxic methyl mercury. Small fish eat or
absorb methyl mercury, which becomes more concentrated as it moves up the food
chain into large predatory fish. Mercury binds to the meat and cannot be removed
from fish by cooking or removing the fat.
See here for more information on
minerals
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of several studies on various supplements and natural medicine topics, including
mercury toxicity, and
their practical interpretation by Ray Sahelian, M.D. For past issues, see
Newsletter2006.
Mercury in Sushi
Sushi is more popular than ever, but eating sushi may expose us to a
higher level of mercury than we may realize.
In January of 2006, Eli Saddler of gotmercury.org, a campaign of California-based Sea Turtle
Restoration Project, went to six top sushi restaurants in Los Angeles to test
the mercury levels in the fish they serve.
The tuna samples from the six popular sushi restaurants in Los Angeles were
taken to a Southern California lab for testing.
The samples had an average mercury level of 0.721 parts per million, about 88
percent higher than the Food and Drug Administration maximum level of 0.383 ppm
for fresh and frozen tuna.
Big-eyed tuna and blue and yellow-finned tuna are the most popular varieties
used in sushi restaurants. Older and bigger fish are considered best suited for
sushi but Saddler said it was not widely known that fish with longer lives carry
more mercury than others.
Studies show seafood like shrimp and salmon with short life spans pose almost no
risk of carrying mercury. Long-living, large
predatory fish like tuna are the most likely to have mercury contamination.
Dr. Sahelian comments: Unless you are eating a large
amount of sushi on a regular basis, I don't think you need to be concerned. Just
eat less tuna sushi and have a variety of different fish.
Mercury in Tuna and Fish
In May 2006, San Francisco Superior Court Judge Robert Dondero ruled that
tuna companies do not have to put labels on their cans warning the fish contains
mercury. The lawsuit was brought by California's attorney general Bill Lockyer,
who in 2004 sought to ban the sale of canned tuna without mercury warnings.
Lockyer sued Del Monte Foods, maker of StarKist tuna; Bumble Bee Seafoods, a
unit of Connors Brothers Income Fund of Canada, maker of Bumble Bee tuna; and
Tri-Union Seafoods, maker of Chicken of the Sea tuna. The complaint alleged the
firms violated state Proposition 65, an initiative approved by voters in 1986 to
require firms to issue warnings before exposing people to "known carcinogens or
reproductive toxins." Although most fish contain trace amounts of mercury,
some species, such as tuna and swordfish, can have higher levels.
Tilapia and trout have low mercury levels, as do shrimp, crab and
scallops. Both farmed and wild salmon are low in mercury and high in essential
omega-3 fats. As well, fish oil supplements are a safe way to get omega-3 fatty
acids because they are generally made from smaller fish like sardines and
anchovies.
Mercury Dental Filings
August 2006 - Two long-awaited, government-funded studies found no evidence that dental
fillings containing mercury can cause IQ-lowering
brain damage or other
neurological problems in children. Children with such fillings were no more
likely than other youngsters to suffer such problems. The
studies are unlikely to end the fierce debate over the long-term effects of what
are known as amalgam fillings. Amalgam fillings, also called silver fillings,
are made of mercury and other metals and have been used by dentists for more
than a century. But their use has dropped in recent years as more and more
doctors switch to resin composite fillings, which are considered more appealing
because they are white.
September 2006 - Government health advisers
rejected a federal report that concluded the mercury-laden amalgam that dentists
use to fill cavities was safe, saying further study was needed. A panel of Food
and Drug Administration advisers did not declare silver fillings were unsafe.
But in a 13-7 vote Thursday, the advisers said a federal report didn’t
objectively and clearly present the current state of knowledge about the
fillings. In a second 13-7 vote, the panelists said the report’s conclusions
about safety weren’t reasonable.
June 2008 - Mercury fillings may cause health problems in pregnant women, children and fetuses, the Food and Drug Administration has admitted. Millions of Americans have the fillings, or amalgams, to patch cavities in their teeth. "Dental amalgams contain mercury, which may have neurotoxic effects on the nervous systems of developing children and fetuses," the FDA said on its Web site. "Pregnant women and persons who may have a health condition that makes them more sensitive to mercury exposure, including individuals with existing high levels of mercury, should not avoid seeking dental care, but should discuss options with their health practitioner," the agency said. Mercury has been linked to brain and kidney damage at certain levels. Amalgams contain half mercury and half a combination of other metals. Only 30 percent of fillings given to patients were mercury-filled ones as of 2003, according to the American Dental Association (ADA). Other options include glass cement and porcelain as well as other metals such as gold, but they cost more and are less durable.
Mercury Dental Filings
controversy continues - Sept 2006
Food and Drug Administration reviewed 34 recent research studies and
found "no significant new information" that would change its determination that
mercury -based fillings don't harm patients, except in rare cases where they
have allergic reactions. Consumer groups opposed to the use of mercury for
dental filings disputed the FDA's conclusions. The groups plan to petition the
agency for an immediate ban on use of mercury dental filings in pregnant women.
Amalgam fillings, also called silver fillings, by weight are about 50 percent
mercury, joined with silver, copper and tin. Dentists have used amalgam to fill
cavities since the 1800s. Today, tens of millions of Americans receive mercury
fillings each year. Amalgam use has begun to decline, however, with many doctors
switching to resin composite fillings, considered more appealing since they
blend better with the natural coloring of teeth. With amalgam fillings, mercury
vapor is released through tooth-brushing and chewing. In general, significant
levels of mercury exposure can permanently damage the brain and kidneys. Fetuses
and children are especially sensitive to its harmful effects. Scientists have
found that mercury levels in the blood, urine and body tissues rise the more
mercury fillings a person has. "If substantial scientific evidence showed that
dental amalgam posed a threat to the health of dental patients, we would advise
dentists to stop using it. But the best and latest available scientific evidence
indicates that dental amalgam is safe," said Dr. Ronald Zentz, senior director
of the American Dental Association's council on scientific affairs. Rep. Diane
Watson, D-California., who has introduced legislation that would effectively ban
the use of mercury in dental fillings by 2008. Watson will press the FDA for a
ban and call on the agency to study the environmental impact of dental mercury.
Also on the legislative front, Sen. Mike Enzi, R-Wyoming., and other Senate
colleagues have asked President Bush's nominee to head the FDA about the safety
of mercury fillings.
Mercury Questions
Q. Are there any herbs or antioxidants such as
lipoic acid,
acetylcarnitine,
or dmae that can neutralize
mercury toxicity?
A. I have not come such research at this time. It's
possible many do, I just have not seen specific research.
Q. Should women avoid eating canned tuna? According to
Consumer Reports, this is what they say, "Pregnant women should not eat canned
tuna because it may contain harmful levels of mercury."
A. Government tests found instances where canned light
tuna had as much mercury, a potentially harmful heavy metal, as white tuna, also
known as albacore. High levels of mercury in the bloodstream may harm developing
nervous systems, according to the Food and Drug Administration. Fish and
shellfish are the main sources of mercury exposure for humans. However, I don't
think one needs to completely avoid canned tuna. One or two cans a month should
be perfectly okay.
Q. Is excessive mercury ingestion a cause of autism?
A. We found a study that evaluated the role of mercury in autism.
Low-level chronic mercury exposure in children and
adolescents: meta-analysis.
Pediatr Int. 2007 Feb;49(1):80-7. Department of Paediatrics, Kwong Wah
Hospital, Kowloon, Hong Kong.
Mercury is a well-known neurotoxin. There are three kinds of mercury
exposure: elemental mercury poisoning, inorganic mercury poisoning and
organomercury poisoning. Organomercury is the most toxic. Twenty-four hour urine
for mercury and blood mercury are the gold standards for diagnosis of mercury
poisoning, including low-level chronic mercury exposure. Other tests for mercury
level are discussed. The purpose of the present paper was to review recent data
on the nature, pathophysiology, pharmacokinetics, diagnostic methods, treatment
and the linkage to neurodevelopmental disabilities of mercury exposure in
children. A literature search was undertaken of MEDLINE (1980-2003), and
American Academy of Pediatrics, American Medical Association, American Dental
Association, World Health Organization and Center for Disease Control websites.
The search string 'mercury' was used in MEDLINE and articles were selected as
appropriate by two independent reviewers. All relevant information was reviewed
and data were extracted by two independent reviewers. Based on the meta-analysis
of the accuracy of hair mercury, hair mercury levels correlated with mercury
level in blood, with 24 h urine and with cord blood. However, the correlation
for hair mercury level with 24 h urine level and blood level was not high enough
to replace them in clinical decision-making of individual patient.
Epidemiological evidence has shown that low-level mercury poisoning is not a
cause of autism. The risk of neurodevelopmental disabilities from low-level
exposure to methylmercury from the regular consumption of fish is still
controversial even after combining results from different epidemiological
studies worldwide. There is a lack of data in the literature about the effect of
chelation therapy in children with neurodevelopmental disabilities. CONCLUSION:
Mercury poisoning should be diagnosed only with validated methods. There is no
evidence to support the association between mercury poisoning and autism.
Q. I have a question regarding Alpha Lipoic Acid and mercury dental fillings. I
have not allowed any new mercury fillings to be placed in my mouth for over 20
years now. But I do have a few small ones left that I do not want to remove for
various reasons. As they need to be removed or repaired, they are of course,
repaired without mercury. I am telling you the age of the fillings because I
have read that the mercury/vapors have a life that diminishes over time.
Therefore, it is my understanding that my mercury fillings would not be as
problematic as new ones. In the past, I have read protocols for removing mercury
and other toxic metals from the body. They say that
Alpha Lipoic Acid
is very effective, but
that if mercury is present, it has the ability to remove it, but then redeposits
it in the brain. I am hoping that in my case, you would believe that I have
nothing to worry about, if I want to take a reasonable daily amount of
Alpha Lipoic Acid
in my daily regimen. I
believe I read those protocols on a website that was treating autism. I would
love to reap all of the many benefits of taking
Alpha Lipoic Acid
without having to worry
needlessly about damaging my brain. Please give me your opinion on this subject.
A. We have not come across any studies regarding the role of
Alpha Lipoic Acid and
mercury fillings.
Q. I am interested in lowering my body burden of mercury
and arsenic. Some of what I have read about chelation makes me doubtful of its
safety, so I am looking for other means to reduce levels of the two
aforementioned heavy metals.
A. We have not explored this topic in any great detailed knowledge
yet. Many people who think their symptoms are due to arsenic or mercury
poisoning may just be guessing. It is important to have two different labs
confirm that a person does how toxic levels of mercury or arsenic before
attributing symptoms to this toxicity.
Q. I like your website otherwise, but you should take
into account the amalgam disease, that is mercury intoxication
and the associated systemic candida - it's really widespread, but mainstream
medicine does still NOT recognize it.
For example, alpha lipoic acid is now more commonly used as a mercury chelator,
because of its disulfide group that
attaches readily to mercury atoms. Its unique ability to cross brain blood
barrier (BBB) makes it a must for mercury chelation. It is the only better known
substance to chelate mercury from brains. The synthetic chelators DMSA or DPMS
also binds to mercury, but they are not able cross BBB, and so cannot chelate
mercury out from brains or organs. The side effects for a person taking alpha
lipoic acid is what you'd expect from mobilizing mercury around in the body, as
many mercury intoxicated people can tell you, ranging from heart palpitations to
insomnia and feelings of tiredness, panic attacks, anxiety, serious depression,
and spaciness. It can also flare up candida symptoms as the
immune system gets compromised with the mercury moving around in bloodstream.
Alpha lipoic acid is potentially dangerous for people taking it in larger doses
when heavy metal poisoned, as it can redistribute metals into brain, instead of
taking them out as desired. I am also a victim of mercury poisoning, and I can
tell you that B12, at least the cyanocobalamin form is by far the most potent of
all common vitamins to cause serious side-effects (when e.g. mercury poisoned),
even potentially very dangerous ones, if taken at large doses (1 mg). My
symptoms were heart palpitations, severe chest pain, and a very high
bloodpressure (180/110), possibly even much higher initially. I do not have
heart problems (now), and im not allergic to or deficient in B12, and I do not
get adverse side-effects from it any longer, now 1 year after post-amalgam
removal. Many other substances than those mentioned here are likely to cause
mobilization of heavy metals/flare up candida, so you should keep this in mind,
when people report side-effects from vitamins etc. If people take vitamins for
their depression and find that it works, they are likely not deficient in them
to the point that it would cause depression, but rather because it helps against
metal toxicity - B12 is also a potent anti-depressant when mercury poisoned I
can tell.
A. We seriously doubt that the alpha lipoic acid and B12 side
effects you report are due to mercury poisoning. Most people have similar alpha
lipoic acid side effects when they take high dosages and we don't think it is
related to mercury poisoning.