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Ethylmercury Intoxication from Thimerosal in Vaccines

arie_ at hotmail.com arie_ at hotmail.com
Sun Apr 9 11:24:39 EST 2000


I acquired the following interesting article.

arie


article:
==========================================

Ethylmercury Intoxication from Thimerosal in Vaccines
Andrew Hall Cutler, Ph. D., P. E.
Minerva Laboratories
(949) 857-0410
AndyCutler at aol.com

The average adult weights 65 kg.

The average 6 month old (girl) weights 7.2 kg,  with a 5-95 percentile
range of 5.8 to 8.7 kg.

Adults excrete methylmercury (and presumably ethylmercury) with a half
life of about 65 days, though it is important to note some fraction of
the population have dramatically longer excretion half lives (see
Al-Shahrisani and Shihab,  Arch. Eniron. Hlth. vol 28 pp342-4 1974).

There is a clinical report of approximately 50 adults becoming
poisoned by ethylmercuric chloride,  and it was possible to estimate
the dose for each adult and correlate this with clinical presentation
(Zhang,  Clinical Observations in Ethly Mercury Chloride Poisoning,
Am. J. Ind. Med. vol 5, pp 251-8, 1984).  It was observed that death
occurred at a dose of about 200 mg, and substantial impairment
requiring hospitalization occurred at 50 mg (toxin in foodstuff before
cooking). Estimated actual absorption was about half this.

The population distribution of toxin sensitivity falls on a "probit
plot," which is to say it is log normal.  The "standard deviation" is
almost invariably a factor of 2 for almost all toxins (see Hogdson,  A
Textbook of Modern Toxicology,  Elsevier,  New York,  1987,  pp
240-3).

It is not clear whether infants excrete organomercurials,  since these
are excreted only in bile and infants do not produce much bile.

The amount of mercury deposited in a poisoning victim's brain is
determined by the competition between excretion in the bile and
metabolic conversion to inorganic mercury which is the chemical
species that causes the toxic effects.  In normal adults these two
processes occur at similar rates. 
Metabolic conversion of organic to inorganic mercury should be as fast
or faster in infants as adults since it is a byproduct of oxidative
phosphorylation and the infant metaoblic rate is higher than the adult
rate.

Since the patients in Zhang's work did excrete large amounts of
mercury we can presume that they retained a fraction of it.  This
fraction is estimated to be 10-30% of the ingested amount,  or 5-15%
of the total amount in food: 
thus

Adult dose of retained mercury leading to clinically obvious
impairment is 2.5 to 7.5 mg, or 38-120 mcg/kg.  For simplicity I will
use 80 below.

Adult dose of retained mercury leading to death is 10-30 mg, or
150-450 mcg/kg.  For simplicity I will use 300 below.

Since the numbers are not very precise,  I have rounded to 2 places
above.

The dose an infant receives of mercury by 6 months is 93 mcg,  or for
the 5-95 % ile,  9.6 to 16.3 mcg.

Since infants receive their mercury by injection (as thimerosal in
vaccines) there is no dosage uncertainty.

If infants do not excrete organic mercury at a significant rate,  most
of it will be converted to inorganic form to exhert its toxic effects.

If infants do excrete organic mercury as well as adults,  then some
fraction of infants who are slow excreters (per Al-Shahrisani and
Shihab) will convert most of the injected mercury,  and the rest will
convert some and excrete some as adults do.

Considering those infants who retain and convert most or all of the
mercury as this represents at least some of the infant population and
perhaps all of if,  the following ratio between the infant dose and
the adult doses leading to impairment and death respectively are:

                             Large infant            Small infant
Impairing dose          0.12                           0.20
Lethal dose               0.032                         0.054


The adult exposure effect levels above will be presumed to be for
"average" adults since the exposed population was randomly selected. 

Thus,  the number of standard deviations below the mean at which these
effects occur may be calculated as 

X = - ln (fraction of exposure) / ln ( 2 )

and the resulting values are:


                             Large infant            Small infant
Impairing dose          3.1                           2.3
Lethal dose               5.0                           4.2

By consulting standard tables of the error function as may be found in
any edition of the CRC Handbook of Chemistry and Physics,  or Perry's
Chemical Engineer's Handbook,  or Lange's Handbook of Chemistry,  we
can see that the fraction of infants in each group reaching the
indicated threshhold is:

                             Large infant            Small infant
Impairing dose          0.0011                     0.011
Lethal dose               0.0000003               0.00003

It is evident that a small enough number of infants will die from
vaccine induced mercury poisoning that this will not be noticeable
statistically and the deaths likely would be attributed to some other
commonly expected cause. 
However,  the number of infants experiencing significant impairment is
substantial.  From a public health standpoint 0.1 to 1.1% of the
population is a HUGE number.  It is reasonable to consider the
hypothesis that the recent increase in autism,  ADHD and learning
disabilities is the expression of the underlying pathological process
mercury intoxication from injected thimerosal puts in place.






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