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From the international Amalgam Mailing list :
Talbot ES.  "Injurious effects of mercury as used in dentistry".  MISSOURI
DENT J, 15:124-30 (March, 1883).

  The subject of mercurial poisoning from the use of amalgam fillings in
decayed teeth, has given rise to numberless articles, and has been a source
of discussion in dental societies since its introduction into this country.
Symptoms of mercurial poisoning have manifested themselves in cases where
these amalgams have been employed, causing the scientific members of the
profession to investigate these fillings, to determine if these symptoms
are due to the mercury contained in its composition.  Nor is this investiga-
tion confined to men of science;  the ordinary practitioner is constantly
meeting these symptoms, and by careful observation will be able to diagnose
these cases when met with.  I will mention two cases which have come under
my notice.

  January 18, 1878, Mrs. W_____, 29 years of age, had several amalgam fill-
ings inserted by me.  At that time, and for the three succeeding years, she
was under a physician's treatment for antroversion of the uterus, when she
was dismissed by him as cured.  During this time she consulted me at intervals
in regard to her teeth.  For a year past she has complained of trembling at
times, coldness, headache, swelling of the limbs, enlargement of the glands,
and pain about the jaws, tongue swollen and sore, teeth loose and tender upon
pressure, marked salivation, and a metallic taste in the mouth;  appetite
poor, and bowels irregular;  symptoms gradually increasing until six weeks
ago when she was completely prostrated, and confined to her bed part of the
time.  Wishing to obtain the opinion of others, I consulted three able phys-
icians, all of whom pronounced it a case of mercurial poisoning.  Four weeks
ago I removed all the amalgam fillings at one sitting, and replaced them with
gutta percha.  A slight improvement was noticeable within a week, and a few
of the symptoms disappeared.  I have refilled some of the teeth with gold,
hand pressure being required on account of the soreness.  The metallic taste
had disappeared, the tongue is normal in size, and where before she was
irritable and nervous, she is now bright and cheerful, and gaining steadily
in weight.

  Miss M_____, a nurse, 40 years old, came to me at the suggestion of her
physician, to have her teeth attended to.  Soon after her recovery from
diphtheric paralysis of the throat, she had a tooth filled with amalgam.
She experienced a disagreeable sensation and some pain immediately after
the operation.  She suffered greatly from the tooth, and had an excessive
flow of saliva.  Her taste was impaired, and she felt a paralyzed sensation
of the muscles upon that side of the mouth.  In nine days she had the tooth
extracted.  The saliva gradually ceased flowing, but at the time of her
visit to my office, four weeks after her tooth was extracted, she had not
entirely recovered the normal condition of the muscles.  Generally, the
poisonous effects of amalgam filling do not manifest themselves immediately
after the filling is inserted.  Years may elapse before the symptoms indic-
ative of mercurial poisoning, which fact but adds to the danger of this sort
of stopping for the teeth.  The suspicions are not aroused to the real cause
of ailments, until the system becomes saturated.  Occasionally other causes
undermine the system, and place persons in a condition susceptible to its
toxic influences.

  I found the general opinion of writers on this subject to be, on the one
hand, that when mercury and alloys formed a chemical union, and the hardening
process took place, the mercury could not detach itself from the other metals.
On the other hand, that a chemical laboratory must be set up in the mouth,
and the mercury converted into some of the toxic compounds, to produce sys-
temic effects.  All experiments hitherto, so far as I know, have sought for
the results by supposing that the acids of the mouth acted upon the mercury
of the amalgam.  These experiments were made largely, if not wholly, from a
chemical standpoint, and the results in all cases were wholly insufficient
to explain the cause of mercurial poisoning.  These experiments were con-
ducted out of the mouth with the different acids at all strengths and at all
temperatures without finding any traces of mercury with their reagents.
Other results could hardly be expected when we consider that nitric acid
affects mercury only at 60 degrees Far., sulphuric acid only when heated,
and hydrochloric acid has no effect upon it.  Knowing that mercury gives off
vapors at all temperatures, which are increased by the action of the heat,
I commenced a series of experiments to ascertain to what extent this change
takes place in amalgam fillings, and if it is possible for the vapor of mer-
cury to be liberated after the chemical change or hardening process has

  In conducting these experiments, I prepared the ammonio-nitrate of silver,
as that is a delicate reagent, and with it wrote upon white paper.  After
putting the amalgam to be tested in a bottle, the strip of paper was placed
across the mouth of the bottle and the stopper cemented.  Should a mercurial
vapor arise, the letters on the paper would become black.  Leaving the bot-
tle for ten minutes I examined it again, and found the writing in plain black

  This is one of the many experiments similarly conducted, the amalgams vary-
ing in age from six months to sixteen years, and immersed in both saliva and
water, with a water bath attached to keep them at the normal temperature of
the body.  They were performed in the dark, as the rays of light decompose
the ammonio-nitrate of silver.  In each instance, the vapor of mercury re-
sponded to the test.  To make sure that the amalgams caused the chemical
test, an empty bottle was subjected to the same tests, with, of course, no
results.  The rapidity with which the evaporization of mercury takes place
depende upon three factors, namely:  the temperature, the area of exposed
surface, and the amount of discoloration upon the filling, and not upon the
quantity of mercury contained in the fillings.

  The vapor is given off proportionately with the increase in temperature,
the heat of the body being greater than the average atmospheric temperature;
the vapor which exudes from a filling in the mouth, exceeds that from a like
quantity of mercury exposed in the open air.  Amalgams are generally inserted
where large fillings and difficult operations are required;  consequently
the amount of exposed surface is great, and yields vapor abundantly.

  The manufacturers are endeavoring to place upon the market amalgams which
will not discolor in the mouth.  Do they consider the disasters they are
encouraging?  The bright surfaces are favorable to vaporization, and Dr.
Watt, who has considered this subject thoughtfully, says:  "The worst cases
of poisoning we have witnessed are those in which the amalgams retain their
original bright color".

  Dr. Bartholow in his work on THERAPEUTICS says:  "As used in the mechanical
arts by gilders and others, the fumes of mercury cause wasting, ptyalism,
necrosis of bones, trembling, impaired intellect, and, in women, abortion".

  Professor Haines while journeying on the Pacific coast this spring, visited
the mercurial mines, and found, in consulting the resident physician, that
few of the workmen escaped salivation, and those connected with the distill-
ing process were obliged to protect the lungs by wearing a shield over the
mouth and nose.  The foreman of the works, while passing a leaking pipe,
inhaled the vapor of mercury, and became so impregnated that he was for a
time delirious.  The doctor was puzzled that some of the miners, in digging
the sulphide of mercury, were salivated, and others were not affected.  Upon
investigation he discovered that the smokers were the men who were affected
by the poison;  that in rubbing the tobacco in their hands they mixed the
particles of the ore with the tobacco, and the heat in burning reduced the
ore to pure mercury, which was drawn through the stem into the lungs.  They
ceased smoking in the mines, and were not affected after.  Parish says that
long trituration of calomel increases its power to salivate.  This is applic-
able to all preparations of mercury used with an excipient medicinally.  The
homoeopaths rub up pure mercury with the sugar of milk into different grades,
and these are the finest forms in which mercury is prescribed, and yet the
severest cases of salivation and constitutional symptoms have been produced
by these agents on account of their being so readily taken up by the blood.
Is it not a reasonable supposition that, as the poisonous symptoms are pro-
duced in proportion with the subdivision of the particles of mercury, that
the system will be more seriously affected by the vapor of mercury, which is
finer than any mechanical subdivision can be.  In order to ascertain the
effects of the vapor of mercury, I have employed it in a series of experi-
ments upon plants and animals.

  I prepared three two-ounce bottles.  The first contained ten grains of pure
mercury;  the second, an amalgam filling three months old;  the third was an
empty bottle.  In each of the bottles I put two roaches, and then covered the
mouths of the bottles with gauze.  In two days the one in bottle with pure
mercury died, the remaining one lived nine days.  In bottle containing amal-
gam filling one roach lived four days, while the other lived eleven days.
Those in the empty bottle lived fifteen and sixteen days.  The numerous
experiments of this sort proved that the roaches in the bottles containing
amalgams invariably died before those in the empty bottles.

  Among experiments upon animals was one upon a guinea pig placed on a gauze
platform in a glass jar over pure mercury.  He presented all the symptoms of
mercurial poisoning.  He became emaciated and trembling, the body and limbs
were cold.  He lingered along for two weeks, and died.  It is the opinion of
many eminent scientists that mercury inhaled into the lungs produces a more
heightened effect than when taken into the stomach.  Among this number Prof-
essor Stille in his THERAPEUTICS (Vol. II, page 789), says:  "Of the several
modes by which mercury is made to enter the body, inhalation most speedily
produces the specific influence of the medicine, -- which theory confirms
the belief that the vaporization of mercury from amalgam fillings, occurring
as it does constantly, and being carried into the lungs without cessation,
is a most effective manner of producing mercurial poisoning.  All persons
are not equally affected by the vapor of mercury;  while possible for some
to inhale mercury without deleterious effects, others would express the most
decided symptoms of mercurial poisoning with less quantity.  Colson states
that in 1821-23 he, with several other interns and externs of the venereal
wards of the Hospital de la Petite were salivated by the mercurial atmos-
phere, nor did they get rid of the affection while they continued to frequent
these wards.


  FIRST. -- Mercurial vapor is given off from amalgam fillings at all ages
and from all varieties.  Even from fillings sixteen years old the vaporiz-
ation is sufficient in quantity to respond to chemical tests.

  SECOND. -- Minute doses of mercury, if taken internally three times a day,
are capable of producing decided effect.

  THIRD. -- Mercury, when inhaled into the lungs, is far more active than
when taken into the stomach.

  FOURTH. -- If small doses, taken into the stomach occasionally, are cap-
able of producing marked effect, and the vapor is much more active than the
solid preparation of the metal, is it not a necessary consequence that amal-
gam fillings, which, as I have proved, are constantly giving off mercury
fumes to be inhaled into the lungs, not a few times daily, but always, with-
out cessation day or night, is it not a necessary consequence that in many
sensitive persons such fillings must produce deleterious effects?

  FIFTH. -- When tons of this material are consumed annually, is it not
credible that many constitutions are affected?

  SIXTH. -- Physicians in treating dyspeptics, anaemics and persons suffering
>from nervous debility, would do well to examine the mouths of patients, and
know if artificial teeth on red rubber, or fillings of natural teeth, have
in their composition mercury or any of its compounds.