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Dental Amalgams
and
Toxicology of Mercury
Medical Chemistry
and
Biochemistry
Institute of Medical
Biochemistry
Medical Chemistry and Winter
Biochemistry
term
Category I
© Institute of Medical Biochemistry and Laboratory Diagnostics of the General University Hospital and of The First
Faculty of Medicine of Charles University in Prague - 2005-2016
Why is mercury so important
for dentists?
(Dental) Amalgams are formed from mercury
Amalgam (from Greek)
amalgamation
 Amalgam = Liquid or solid alloy of mercury (or gallium) with one or more metals, e.g.,
with sodium, potassium, silver, gold, zinc, cadmium, lead.
 Amalgam is usually prepared by direct contact of mercury with proper metal (dentists) at
room temperature, eventually electrolytically by metal reduction from aqueous solutions by
electric current on mercury cathode (polarography, voltammetry).
 Lifetime of dental amalgams 6 years (traditional alloys) – 20 years (copper-enriched alloys)
 Amalgams are used:
 in stomatology (dentistry) as a hard restorative material of silvery-grey appearance
(silver amalgam);
 in electrochemistry;
 in production of silver mirrors (tin, silver amalgam);
 in gold and silver mining
 in measurement engineering (thermometers, manometers (barometers etc.))
Dental Amalgams and Hg-Toxicology
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Selection of proper dental material

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





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Nucleation, polycrystalline grain structure, microscopic and macroscopic
composition
Compressive strength
Tensile strength
Thermal properties (thermal diffusivity, thermal expansion)
Adhesivity to tooth material (dentine, enamel)
Changes in time
Possible formation of galvanic cells, origin of galvanic currents
Corrosion properties
Dimensional changes
Compressivity
Hardness
Plastic deformations (creep)
Fracturability
Appearance (silvery-grey, lustre, correspondence with background)
Toxicity
Allergic reactions, biological compatibility
Price
Availability (easy of access)
Buildability
Easy of formation
Wish of the patient, health insurance, cost!!!
Dental Amalgams and Hg-Toxicology
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Advantages of amalgams

Easy to prepare

Low (or none) toxicity

Low price

Long lifetime
Disadvantages of amalgams

Silvery-grey appearance

Content of mercury

Formation of galvanic (electrochemical) cells (e.g. with aluminum)
Dental Amalgams and Hg-Toxicology
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Requirements on dental material (e.g., on
amalgam) in course of preparation

Condensing, Setting rate – the dentist must have enough time to fill properly
amalgam into the cavity, to arrange it mechanically. However, in 1 – 2 hour the
filling must be so hard that the patient can use it (eat). In 24 hours it reachs
maximal hardness practically.

During hardening - the dimensional changes have to be neglectable – the tooth
would be ruptured in case of massive expansion, or the filling would come out in
case of massive contraction.

Chemical resistance - the filling must be chemically and toxicologically inert to
the surroundings in mouth.
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History of the Use of Amalgams for Dental Purposes
 The first people, which used amalgams to fill cavities, were the Chinese in the 7 th century.
 First dental experiments in modern history: French dentist Auguste Taveau (1826): developed a dental
amalgam from silver coins and mercury.
 He prepared a middle rigid paste composed from silver and mercury, which filled a tooth and solidified it
in required shape. Taveau’s fillings were cheaper than the used gold leafs, used at that time and they were
better workable. This early amalgam was low in mercury and had to be heated in order to dissolve the
silver at any appreciable rate. However, they exhibited some serious disadvantages. The amalgam
increased dramatically its volume during the solidification process (today is slight expansion considered
as advantageous) and it stacked out from the tooth and it complicated the proper occlusion (at that time
did not exist the tools for amalgam polishing) or the tooth could be ripped be internal stress. Therefore,
Taveau’s „silver paste “ was not popular too much.
 The brothers Crawcour, New York, used advertisement powerfully, they achieved big success. They were
charged by other dentists with amorality and professional incompetence, charlatanism, later, the used
material, which the brothers used for dental filling, was impeached. It was declared that amalgam is not
suitable for dental fillings, because it is harmful and therefore it cannot be placed in human mouth. It was
emphasized that mercury volatized from the filling gradually and it is harmful for human organism. Due
to these attacks the brothers Crawcour had to leave New York. Since then it was not possible to use
amalgam for any prestigious dentist, to do not be discredited. The anti-amalgam campaign prolonged. The
illness with unknown causations were ascribed to the amalgam fillings (paralysis of lymbs, throat
diseases, even tuberculosis etc). Dental Amalgams and Hg-Toxicology
2015/2016
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History of the Use of Amalgams for Dental Purposes

In 1843 representatives of American Dental Association (ADA) prohibited the use of
amalgam generally. Some dentists were proscribed from ADA, because they publicly used
amalgam. Some other dentists officially, publicly criticize it, however, they used it
frequently in their patients secretly.

About 1870: one of the most famous American dentist Joseph Foster Flag declared for
the application of amalgam. He declared that after many years of experiments with this
alloy, he can conclude that the teeth filled by amalgam have the longer durability in
comparison with other fillings, including gold. The amalgam alloys have been the most
frequently used type of fillings since the end of 19th century.
Dental Amalgams and Hg-Toxicology
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Gold and Silver Mining






Mercury has been used in the gold and silver mining processes due to the ease with which mercury
amalgamates with them.
Mercury has been often used to separate the gold from other heavy minerals.
 Small particles of gold are washed from sand or gravel deposits
 After all of the usable metal had been extracted from the ore, mercury was poured down a long
copper trough which formed a thin coating of mercury on the surface.
 The waste ore was then poured down the trough, and any gold in the waste amalgamated with
the mercury.
 This coating was occasionally scraped off and distilled to remove the mercury, leaving behind
fairly high-purity gold.
Mercury amalgamation was first applied to silver ores with the invention of the patio process in
Mexico in 1557 (Bartolomé Medina).
Other amalgamation processes were invented for processing silver ores, including pan amalgamation
and the Washoe process.
With the invention of mercury amalgamation to treat silver ore, mercury became essential to the
silver mines of the New World. The Spanish Empire transported mercury from Almadén across the
Atlantic to supply the silver mines of Zacatecas and Potosí. Another source for mercury in the
Spanish Empire was the mine of Huancavelica in Peru, discovered in 1563. In 1648, the Viceroy of
Peru declared that Potosí and Huancavelica were "the two pillars that support this kingdom and that
of Spain.“
Mercury amalgamation is still commonly used by small-scale gold placer miners, especially in lessdeveloped countries, most notably Brazil.
Dental Amalgams and Hg-Toxicology
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Voltammetry, polarography

Mercury is the preferred electrode material for the analysis of metals by polarography
(voltammetry, potentiometric stripping analysis). The formation of amalgams facilitates
the reduction of most metal ions in aqueous solutions that is normally not possible,
because their reduction potentials are more negative than the potential for the reduction of
the solution (the potential of hydrogen reduction is shifted to relatively negative potentials
on mercury (“hydrogen overpotential”) and thereby relatively wide potential window for
metal reduction is formed).

Production of electrochemical detectors, of voltammetric electrodes, which can
successfully replace the famous mercury electrode.
Dental Amalgams and Hg-Toxicology
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Composition of dental amalgams (% m/m)
American Dental Association (ADA) prior to 1986
ISO 1559
Ag
≥ 65 %
≥ 40 %
Sn
≤ 29 %
≤ 32 %
Cu
≤6%
≤ 30 %
Zn
≤2%
≤2%
Hg
≤3%
≤3%
Type
Ag [%]
Sn [%]
Cu [%]
Zn [%]
Other [%]
In, Pd, Se
TL = traditional lathe cut
70.9
25.8
2.4
1
—
TS = traditional spherical
72
26
1.5
0.5
—
HCS = high-copper spherical
41-61
24-30.5
13-28.3
0-0.5
In 3.4
HCAd = high-copper admixed
62-69.7
15.1-18.6
12.0-22.7
0-0.9
In 10
HCL = high-copper lathe cut
43
29
25
0.3
Hg 2.7
GA = alloy for gallium amalgam
50
26
15
—
Pd 9
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
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




Production of non-mercury part of the amalgam
Lathe-cut
Precisely weighted components of the dental alloy are melted (fused), mostly in inert atmosphere;
Smelt is cast in ingots
“Homogenization” by heating up to 420 °C for 1-2 weeks (for homogenous structure in the whole ingot).
Lathe-turning to small cuts. Their proportions depend on lathe-turning rate as well
Pulverization in ball grinder, grading
Heating up to 100 °C for a few hours to remove internal stresses originating during preparation
The alloy is by heating stabilized for reaction with mercury (otherwise lathe cut would react too fast and
higher amount of mercury would be needed for amalgamation.
Atomization

Spherical particle shape (might be a partly irregular) is
created by means of an atomizing process whereby a spray
of tiny drops is allowed to solidify in an inert gaseous (i.e.
argon) or liquid (i.e. water) environment.
Magnification 100x
Magnification 500x
Dispersion-modified alloy powder.
Dental Amalgams and Hg-Toxicology Lathe-cut particles of conventional
12 of
alloy and spherical particles
2015/2016
silver-copper eutectic alloy .
Types of Most Frequently Used Dental Amalgams
(Generally)
High copper
Lathe cut
Low copper
Silver amalgam alloys
Admixed
High copper
Spherical
Low copper
Traditional Alloys
Lathe cut alloys





Until the 1960s, the chemical composition and micro-structure of available amalgam alloys
essentially the same as those of the most successful systems investigated by G. V. Black
(Black, 1895).
Blend of different particle sizes rather than a unimodel system
Length of particles from 60 to 120 µm, width from 10 to 70 µm, thickness from 10 to 35 µm
Tendency to decrease the dimensions of particles in traditional alloys as well
Ag 66-73 %, Sn 25-29 %, Cu <= 6 %, Zn <= 2 %
Spherical alloys



Introduced on the market during the 1960s
Particle shape is created by means of an atomizing process
Spherical particles generally, the shapes might be irregular, Ø <= 40-50 µm
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High-copper blended alloys




Introduced during the late 1960s
Dispersalloy, Johnson & Johnson Dental Care Co. (~1963)
 A mechanical mixture of two parts:
 traditional lathe-cut alloy;
 spherical alloy;
 Chemical composition of the spherical particles: 72 % Ag and 28 % Cu; it
corresponds to the eutectic composition of the silver-copper system;
 The overall composition of this alloy is approximately 13 % of copper (more
than twice the maximum amount permitted in the ADA)
Preparation
1.
Mechanically mixed
2.
Melted
They can be prepared as lathe cut as well as spherical particles
Other types of high-copper alloys







Selenium addition – to improve the biocompatibility of the amalgams (~1982)
Palladium addition <= 1 % - Pd is relatively expensive
Indium addition ~ 10 % - 30 % - to reduce the mercury vapor released in the mastication
process, higher stability of phases 1 = Ag2Hg3 (~1992-4)
Gallium alloys
By addition of In or Sn can be decreased the melting point of the amalgam below room temperature
This liquid can be then triturated with a silver-tin-copper alloy powder (spherical) in the same
fashion as dental amalgam.
Addition of Pd - to improve corrosion properties
Example of composition: Ga 65 %; In, 18,95 %; Sn 16 %; other 0.5%.
Dental Amalgams and Hg-Toxicology
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14
Amalgam Ag2Hg3= phase 1
Atomic forces microscopy + scanning electron microscopy
Dental Amalgams and Hg-Toxicology
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Crystal lattices
Hg (-39 oC)
Triclinic
Monoclinic
Orthorhombic
Tetragonal
Basal centered
Monoclinic
Triclinic
Rhombohedral
Single face centered lattice (F)
Cubic
Hexagonal
Body centered (I)
Orthorhombic
Primitive centering (P)
Tetragonal
Trigonal
Hexagonal
14 Bravais lattices
Cubic
Dental Amalgams and Hg-Toxicology
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Reactions of amalgams
Traditional alloys

 = Ag3Sn
1 = Ag2Hg3
2 = SnxHg
Ag3Sn + Hg  Ag2Hg3 + SnxHg + Ag3Sn
(x~7-8)


+ Hg 
1 +
2
+

Copper-enriched alloys
 Ag3Sn + Cu + Hg  Ag2Hg3 + Cu6Sn5 + Ag3Sn



+Cu + Hg 
2Cu3Sn+
1 +
Cu6Sn5 +

3 Sn  Cu6Sn5 (single-composition alloys)
 = Ag3Sn
 = Cu6Sn5
 = Cu3Sn
Dispersion-modified, copper-enriched lathe-cut
1.

+ Hg 
2.
2
+ Cu 
1
2
+
2 = temporary intermediate product (from days to weeks)
Cu6Sn5
Gallium amalgams
CuGa + PdGa5 + Ag9In4 + Ag9Ga + β-Sn
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Phase diagram of amalgams
Phase diagram Ag - Hg
Phase diagram Au - Hg
Dental Amalgams and Hg-Toxicology
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Examples of amalgams
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Physical Properties of Dental Amalgam
Properties
Value specified in ISO 1559
Dimensional change [%]
-0.1 - +0.2
Compressive strength [MPa] at 1 hour
Min. 50
Compressive strength [MPa] at 24 hours
Min. 300
Creep (Permanent (plastic) deformation) [%]
Max. 3 %
Type
Compressive
strength [MPa]
30 min; l h; l day
Tensile
strength
[MPa]
Knoop
hardness
Creep
[%]
Dimensional
change
(µm/cm)
53; 89; 430
52
146
2.05
8
TS = traditional spherical;
170; 265; 444
55
174
0.21
0
HCS = high-copper spherical;
122; 220; 486
63
173
0.07
-7
HCL = high-copper lathe cut;
59; 97; 477
45
174
0.17
5
HCB = high-copper blend;
79; 123; 434
50
155
0.24
-7
-; 343; 383
57
-
0.17
16
TL = traditional lathe cut
GA = alloy for gallium amalgam.
Dental Amalgams and Hg-Toxicology
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Dimensional Changes of Dental Amalgams
Expansion
Dimensional change [%]
Contraction
Time [hours]
Contraction, mercury is
still diffusing into the
alloy particles
Crystallization of new
phases becomes the
predominant feature of
the setting reaction
Dimensional changes: a), b) Examples of normal behavior, c) Example
of moisture-contaminated material
Influence on Dimensional changes: type of alloy, particle size, particle
shape, pressure used to condense the amalgam into the cavity
Zn + H2O  ZnO + H2 ........Expansion
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Creep, Elasticity of Dental Amalgams
From Dr. Pavel Branda: Cements and composite materials
Elasticity, Creep
Elastic regime,
linear dependence
Hooke's law
Area of
plastic/permanent
deformation
Reversible Irreversible
deformation deformation
Stress
Short term Long term
load
load
Stress by
destruction,
rupture
Deformation
Irreversible deformation, though in
the area of elastic behavior
Dental Amalgams and Hg-Toxicology
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Elasticity of Dental Amalgams (Creep)
1) True elastic limit
The lowest stress at which dislocations move. This definition
is rarely used, since dislocations move at very low stresses,
and detecting such movement is very difficult.
2) Proportionality limit
The point at which the stress–strain curve deviates from
Hooke's law, i.e., becomes nonlinear.
3) Elastic limit
The lowest stress at which permanent deformation can be
measured. This requires a manual load-unload procedure, and
the accuracy is critically dependent on equipment and
operator skill.
Dental Amalgams and Hg-Toxicology
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From: www.wikipedia.org
23
Compressive strength [MPa]
Compressive strength
Practically equivalent
a)
Coarse-grain, lathe-cut material
b)
Fine-grain, lathe-cut material
c)
Spherical particle material
Optimal content of mercury 44-48 % (m/m)
• the compressive strength will decrease 1 % with each 1 %
increase in mercury above 60 %
• Compressive strength will decrease 1% with each 1 % of porosity
Time [hours]
Comparison of lathe-cut amalgams with tooth materials
Property
Enamel
Dentine
Amalgam
Modulus of elasticity [GPa]
50
50
30
Compressive strength at 7 days [MPa]
250
280
350
Tensile strength at 7 days [MPa]
35
40-260
60
Vickers hardness
350
60
100
Dental Amalgams and Hg-Toxicology
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3times lower
Creep
Permanent (plastic) deformation under constant load after the material has set
Creep is determined by applying an axial compressive stress of 36 MPa to a cylinder of amalgam 6 mm long
and 4 mm in diameter. The specimen is stored at 37°C for 7 days before testing. Time of application: 4 hours
Oral temperature 37 oC is at ~ 0.9 Tm (Tm is the melting temperature) => easy diffusion and deformation
Material type
Creep [%]
Conventional lathe-cut
2.5
Dispersion-modified, copper-enriched
0.2
Copper-enriched, containing 0.5% palladium
0.06
“Ditch“ around the
margins of the
amalgam“
How creep of amalgam causes the formation of unsupported edges which
can fracture
a) Initial restoration; b) Following creep; c) Following marginal fracture
Generally – the higher creep – the higher fractionality (in traditional alloys)
2 = SnxHg … phase responsible for creep


Min. content of 2 phase in v Cu-enriched amalgam + In + Pd
Dental Amalgams and Hg-Toxicology
Cu6Sn5 … low creep
2015/2016
Marginal fracture
Corrosion
Traditional
High Cu
25
Čas [roky]
Corrosion
Degradation due to the electrochemical process
Distinguish: Corrosion X Tarnish
Tarnishing = the loss of lustre from the surface of a metal or alloy due to the formation of a surface coating
The integrity of the alloy is not affected and no change in mechanical properties would be expected
2 = SnxHg …
Easy formation of the anode in galvanic cell  the phase responsible for corrosion
8Sn7Hg + 21O2 + 42H2O + 28Cl-→ 14Sn4(OH)6Cl2 + 8 Hg
Alimentary
tract
 Properly polished amalgam  smaller area  lower tendency to the corrosion
Reaction with the
rests of alloys
(formation of 1 =
 The corrosion products form a seal, which prevents microleakage (positive effect) Ag2Hg3, a 2 = SnxHg)
Air, saliva, salts in mouth
 Copper-enriched alloys, without 2 phase (SnxHg) are more resistant against corrosion
4Cu6Sn5 + 19O2 + 18H2O + 12Cl-→ 6[CuCl2.3Cu(OH)2] + 20SnO
 Addition of Cu does not change substantially corrosion character of amalgam alloys
 Additions of Pd < 1% - substantially improve the character of amalgam alloys
Reactions of amalgam with other metals  formation of galvanic cells  galvanic currents
a)
Attacks of soft tissues
b)
Dissolution of amalgam materials
Dental Amalgams and Hg-Toxicology
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Oxidation - reduction reactions (redox)
Example
Galvanic cell - spontaneous
Anode: Zn=Zn2++2e1st redox system E0(Zn2+/Zn)=-0.76 V
Cathode: Cu2++2e-=Cu
2nd redox system E0(Cu2+/Cu)=0.34 V
Zn(s) + Cu2+ = Cu(s) + Zn2+ U=Ec-Ea
Measurement of redox potential (Secondary school)
Electrolytic cell – Inserted voltage
Anode: Cu = Cu2+ + 2e1st redox system
Cathode: Zn2+ + 2e- = Zn
2nd redox system
Cu(s) + Zn2+ = Zn(s) + Cu2+ U=Ea-Ec
Reduction is always realized at cathode!
E1  E10 
a
a
RT
RT
RT a1red
ln
U  E1  E 2  E10 - E 02 
ln 1red 
ln 2red
nF a1ox
nF
a1ox
nF
a 2ox
Dental Amalgams and Hg-Toxicology
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Oxidation - reduction reactions (redox)
Redox pair
[V]
Redox pair
[V]
Li+/Li (s)
- 3.04
Co2+/Co (s)
- 0.28
K+/K (s)
-2.92
Ni2+/Ni (s)
- 0.25
Na+/Na (s)
- 2.71
Sn2+/Sn (s)
- 0.14
Ca2+/Ca (s)
-2.50
Pb2+/Pb (s)
- 0.13
Al3+/Al (s)
- 1.66
2H+/H2 (g)
+0.00
Mn2+/Mn (s)
- 1.18
Sn4+/Sn2+
+0.15
Zn2+/Zn (s)
- 0.76
Cu2+/Cu (s)
+0.34
Cr3+/Cr (s)
- 0.74
Ag+/Ag (s)
+0.80
Fe2+/Fe (s)
- 0.44
Cl2/2Cl-(g)
+1.36
Cd2+/Cd (s)
- 0.40
Au+/Au (s)
+1.50
Tl+/Tl (s)
- 0.34
Dental Amalgams and Hg-Toxicology
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Oxidation - reduction reactions (redox) I
Standard electrode potentials at 25 oC in aqueous solutions
Dental Amalgams and Hg-Toxicology
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Thermal properties
Material
Thermal
diffusivity
.10-3 [cm2.s-1]
Coefficient of
thermal expansion
.10-6 [oC]
Amalgam
78
25
Dentine
2
8
 Amalgam = good heat conductor
 Dentine = good heat insulator
=> In large cavities it is necessary to line the base of the cavity with an insulating, cavity
lining material prior to condensing the amalgam.
 Amalgam - The coefficient of thermal expansion value for amalgam is
about three times greater than that for dentine
 there is no (minimal) adhesion between amalgam and tooth substance
 Dangerous in case of could or of hot drinks or meals
 Microleakage of moisture
 Microleakage plays an important part in initiating of lesions
Dental Amalgams and Hg-Toxicology
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Biological properties
 According to some literature sources: The patient is briefly subjected to relatively high doses of
mercury during placement, contouring and removal of amalgam fillings. A lower, but continuing, dose
results from ingestion of corrosion products.
 Fears of increased levels of mercury in blood, in urine and morbidity of persons with amalgam
fillings has not been proved!!!
 In vitro studies: Increased levels of Hg found in saliva about 4 and 20 µg/day after filling placement.
However, about the same value of Hg as the dietary intake, later considerably lower than dietary intake.
 In vivo: Probably considerably lower!!!
 Amount of mercury released from amalgams is not sufficient for spontaneous abortion, accumulation in
placenta etc.
 Amount of mercury released from amalgams is decreased by the use of amalgams without γ2 phase
 Allergic reactions: contact dermatitis
Source of mercury
Type
Absorption (ng/d)
WHO
Total
43 000
OSHA (air workplace)
429 000
Amalgam
Elemental
Elemental
1 240 – 29 000
Water
Inorganic
5
Food
Organic
Saliva
Air (home)
Inorganic
Elemental
180 - 1 400
Air (ambient)
Elemental
32 - 96
Dental Amalgams and Hg-Toxicology
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2 220 - 5 572
4 160
31
Safety measures – Precautions
to reduce the risk of contamination of the dental surgery by mercury
 The use of encapsulated materials
 Preparation (trituration) of amalgams (capsules) using special devices - amalgamators
 To store excess, waste or scrap amalgam under water or under chemical fixative solution,
in a sealed container
 Proper flooring without any (or with minimal) joints
 The capsules should be opened away from the face in well-ventilated conditions
 Effective air conditioning or ventilation
 Under normal service conditions, amalgam restorations are covered by a film of saliva.
This reduces the vapor pressure dramatically and largely reroutes the mercury from the
respiratory to the esophageal tract
 The esophageal route's tolerance to mercury is greater than that of the respirator route
 Vapor pressure increases dramatically with increasing temperature
Despite the increased exposure of dental personnel to mercury vapors, examinations of the
health, mortality and morbidity rates for dentists have shown that they are not
significantly different from those of the general population!!!, a fact which should go a
long way towards reassuring those who harbor fears over mercury toxicity.
Dental Amalgams and Hg-Toxicology
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General Phases of Dental Amalgam Preparation
 Proportioning and dispensing, Trituration of compounds, homogenization
 TO secure high homogeneity of the amalgam material
 Too much mercury present in amalgam  relatively hard γ phase (Ag3Sn) is converted into
weak and soft γ2 phase (SnxHg) and a considerable amount of mercury will remain unreacted
 Too little of mercury – not enough to wet the surface of the alloy particles and produce sufficient
matrix phase material  porosity in the set material.
 Condensation
 Ultrasonic condensers - tend to produce local heating of the amalgam – releasing of Hg-vapors
 Good bonding between the incremental layers of amalgam.
 Adequate adaptation of the material to all parts of the cavity base and walls
 Minimal time delay between trituration and condensation,
 Until the amalgam feels hard, a mercury-rich layer has been formed at the surface
 Lathe cuts – high condensing forces
 Spherical alloys – very different condensation characteristics (lower condensation forces)
 Carving
 Removing of the mercury-rich layer on the amalgam surface and rebuilding of the anatomy of the
tooth
 It is necessary to realize it soon after condensing the amalgam
 If the material is too hard  danger of chipping at the margins
 Polishing to achieve:
a lustrous surface
a more acceptable appearance
better corrosion resistance
 To remove irregularities in the surface
 Polishing using graded abrasives, either flours of pumice followed by zinc or ceric oxides with
water as a carrier or by using abrasive impregnated rubber points and wheels
Dental Amalgams and Hg-Toxicology
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Commercial amalgams
2 parts
A. Alloy of metals – in form of powder, capsules (self-activating) or pellets
B. Mercury
Producers (distributors)
(examples – regardless of importance on the market)
•
Ivoclar Vivadent Clinical
•
Nordiska Dental AB
•
SAFINA
•
BOME
•
SDI
•
SCITEM LIMITED
Dental Amalgams and Hg-Toxicology
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34
Frequently Used Dental Amalgams in Czech Republic
Examples of commercially available amalgams
ANA 2000 DUETT
Mixed amalgam containing spherical and dispersed particles with high content of copper. In form of
powder, self activating capsules or pellets.(Ag 43 %, Sn 29.6 %, Cu 25.4 %)
ANA 70 DUETT
Mixed amalgam containing spherical and dispersed particles with high content of copper. In form of
powder, self activating capsules or pellets.(Ag 69.3 %, Sn 19 %, Cu 10.9 % Zn 0.4 %)
SPHERODON-M-POWDER
Mixed amalgam without gamma 2 phase, wthout zink, containing spherical and dispersive particles (ratio
3:2) with higher content of copper, characterized by faster setting and requiring lower condensing
pressures. Composition: Ag 45.5 %, Sn 31.5 %, Cu 23 %. Fillings are mixed with mercury.
SPHERODON-M-DUET Mixed non gamma 2 amalgam with 40 % content of silver. Contains spherical
and dispersive particles of the same composition. It exhibits perfect stability and enhanced resistivity
against corrosion. Composition Ag 40 %, Sn 32 %,Cu 28 %. Safe and hygienic packing, it does not
contain any free mercury. There are mixed fillings with mercury packet.
Dental Amalgams and Hg-Toxicology
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Dental equipments
A programmable amalgamator available for the
mechanical trituration of the alloy and mercury.
Amalgam separator METASYS
MST 1 Metasys – Amalgam separator
Waste disposal: Specialized company (e.g., BOME, Průhonice)
Dental Amalgams and Hg-Toxicology
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80Mercury
- Hg
 Silvery grey metal, liquid under laboratory temperature
 II.B group = Hg+, Hg2+
 Fusion point: -38,8 oC
 Boiling point: 356,9 oC
 Molecular mass: 200.61 g.mol-1
 Relatively high vapors density
 One-atom vapors
 Density ~13 500 kg.m-3 (H2O 1 000 kg.m-3, steel 7 800 kg.m-3,
lead 11 390 kg.m-3, gold 18 800 kg.m-3, osmium 22 480 kg.m-3).
Dental Amalgams and Hg-Toxicology
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Optimální
Optimum
Deficit
Lethal
Letální
Lethal
Letální
Velikost
dávky
Dose
2 ) To x ic k é
2)
Toxic
O p t im á ln í
Optimum
Dental Amalgams and Hg-Toxicology
2015/2016
Toxic
Toxic ká
O ptim á lní
Optimum
Přebytek
Surplus
Incompatible
Ne
s luč ite lné s e
with lifež ivote m
Nedostatek
Lack
Organism
S ta v o rg a n is mu
Incompatible se
Neslučitelné
with lifeživotem
Optimální
Optimum
1) Esenciální
1) Essential
Essential
Toxic
Toxická
Organism
Stav
organismu
Essentiality and toxicity of elements (generally)
(valid for compounds as well)
Lethal
Le t á ln í
Ve lik o s t d á v k y
Dose
38
Biologically important (essential) elements
Numbering 1-18
according to Int. Union
of Pure and Applied
Chemistry (IUPAC)
IIIa, IVa etc. – main
groups - USA, CZ
IIIb, IVb etc. – main
groups - GB
Content in organisms
Biogenic elements of 1st order
Makrobiogenic
1%
Biogenic elements of 2nd order
Makrobiogenic
 0,01 %
Makrobiogenic
Microbiogenic
> 0,001 %
Biogenic elements of 4th order
Microbiogenic
 0,001 %
Biologic importance is not unambiguously proved, nevertheless is (possible)
probable
Significant toxicity
Dental Amalgams and Hg-Toxicology
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Mercury




Naturally present in all components of environment
Normal levels in eruptive rocks and sediments 10-50 ng g-1
Mineral “red lead” (cinnabar) contains 86.2 % of mercury
Mercury is released in environment from natural sources
(mineral efflorescence, volcanic activity, forest wires and
evaporation of oceans) as well as in consequence of human
activity.
 Anthropogenic sources amounted to 60-80 % - elution
(leaching) of wastes in localities with active or terminated
mining of mercury, coal combustion, chlorine production,
elution (leaching) of wastes, combustion in incinerations,
cremation, contaminated waters, cement production, metal
fusion, chemical industry, mining of noble metals by
amalgamation.
Dental Amalgams and Hg-Toxicology
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Examples of background concentrations of mercury species
[ng.L-1] and percentage of methylmercury to total mercury content
MeHg/T-Hg [%] in waters
MeHg
[ng.L-1]
Hg2+
[ng.L-1]
TotHg
[ng.L-1]
MeHg/T-Hg
[%]
14+1
60±4
200±14
120+8
214± 14
180±8
6.5
33
Gijón, ESP
Sweden, SV
35 ±1
0.48-0.77
210±8
245 ±8
14.3
Lake
Bajkal, Russia
0.002-0.16
0.14-2.02
0.14-2.18
1.4-7.3
Stream
Almadén, ESP
0.05-0.34
9.1-43
9.2-43
0.5-7.9
Stream
Alaska
0.04-0.2
0.1-1.4
0.14-1.6
12.5-28.6
Glacier
Antarctica
0.14
0.83
0.97
14.4
Water type
Locality
Waste
See
Spain
Spain
See
Peat
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Use of mercury

Measuring devices:
 Aneroids, barometers
 Thermometers
 Polarographs (Voltammographs)





Bateries (~1 %)
Electrolyzer
Drugs, unguents (???)
Dentistry
Mining of noble metals by amalgamation (underdeveloped
countries)
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September 12th, 2006 11:33,
Teaching in V. Hlavatý grammar school in Czech town Louny was interrupted. Rescue group of
firemen liquidated in some classes drops of mercury. According to the fireman spokesman, the total
volume of mercury amounted to 0.05 L. Toxic compound brought one of students from the third class of
this grammar school. Students were evacuated to the school play ground. At 11 a.m the teaching can
start again.
According to the information of the school director Milan Rieger, in all classes, where mercury was
found, it was necessary to continue with ventilation. All students are all right.
“One student brought mercury to the school. He wanted to show off in the class. Small amount of this
material escaped in some schoolrooms.“, said the director. “The student brought this toxic compound In
rucksack, he took it away by his parents.” Mercury was in dressing rooms as well.
The firemen removed drops of mercury by special cleaner (exhauster) in two schoolrooms, dress rooms
and boxes. This incident is investigated by detectives. The compound will be analyzed.
Dental Amalgams and Hg-Toxicology
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Mercury in subway vestibule closed the station
Action in I.P. Pavlova station through mercury May 1st, 2006 10:41,
Suspicious chemical substance closed subway in the station I. P. Pavlova. The trains did not stopped in
this station for two hour. The firemen found that the unknown compound is mercury.
The substance was on stairs and in vestibule of the station.
The action was realized under cooperation of Prague police and firemen – Special Prague
chemical group and special team of Prague transport organization.
“It was found that the suspicious substance is mercury," said to iDNES the spokesman of firemen
Vít Pernica.
The firemen removed the drops of mercury by special air pump for chemicals from the area of about 30
square meters and the area was cleaned subsequently.
Police department investigated, who brought mercury, and why he gave it in subway.
Dental Amalgams and Hg-Toxicology
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1918 – Austria-Hungary => Czechoslovakia
1993 – Czechoslovakia split into Czech Republic and Slovakia
Nobel prizes in Czechoslovakia (awarded):
1.
Prof. Jaroslav Heyrovský – chemistry - 1959
2.
Jaroslav Seifert – literature -1984
Nobel prizes in Czechoslovakia
(nomination – not awarded):
1.
Edvard Beneš (peace)
2.
Karel Čapek (literature)
3.
Nobel prizes awarded to
natives of Czechoslovakia
1.
Bertha von Suttner (nee Kinská) (peace) – AustriaHungary - Austria -1905
Milan Kundera (literature)
2.
Carl Ferdinand Cori (medicine) - USA - 1947
4.
Jiří Hájek (peace)
3.
Gerta Theresa Cori (medicine) - USA – 1947
5.
Václav Havel (peace)
4.
Peter Grünberg (physics) – BRD - 2007
6.
Tomáš Garrigue Masaryk (peace)
7.
Otto Wichterle (chemistry)
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Prof. Jaroslav Heyrovský (*20. 12. 1890 – 27. 3. 1967)
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Polarograph
first recording analytical device
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First polarograms
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First paper on polarography – 1922
in journal “Chemicke listy”
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December 10th, 1959 (37 years after discovery of polarography)
Prof. Jaroslav Heyrovský was awarded the Nobel prize for
chemistry by the Swedish king Gustaf Adolf VI. in Stockholm
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Order for production of the first polarograph
and one of the first polarographic machines
Dental Amalgams and Hg-Toxicology
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Mercury fountain (Spain) Barcelona, Foundation Miró
Mercury mine Almaden
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Modern polarographic device – small amount of mercury
(produced in Czech republic 21st century)
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Users (developers) of polarography (voltammetry)
•
J. Heyrovsky Institute of Physical Chemistry AS CR
(Department of biophysics, Department of
Electrochemistry)
•
Faculty of Science UK, Prague
•
Univerzity Pardubice, Department of Analytical Chemistry
•
Institute of Biophysics, AS CR
•
Faculty of Science MU, Brno
•
Hospitals, Clinics , Hygienic departments…
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Toxicological Information Centre
(TIC) 1st MF and GFH
Head: M.D. Hana Rakovcová
128 08 Praha 2, Na Bojišti 1
tel.: 224 919 293, 224 915 402
e-mail: tis@vfn.cz
http://vfn.lf1.cuni.cz/tis/english.html
24hours a day (physicians, biochemists, toxicologists, pharmacologists)
Established: 1962 (Prof. Rejsek)
Information for physicians and laymen on course, first aid in case of acute
Poisonings and their treatments
Fast orientation in composition of toxic compounds, clinical and
laboratory diagnostics and corresponding treatment
Dental Amalgams and Hg-Toxicology
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Common forms of mercury:
Valences: 0, +I, +II
1) Metallic mercury (electrodes, manometers, vacuum pumps, etc.);
2) Mercury vapors;
3) Amalgams of mercury (MexHgy);
4) Inorganic compounds (soluble salts (Hg2+) - chlorides, nitrates,
iodides; less soluble salt (Hg+) - chlorides);
5) Organo-metallic compounds (RHgX or RHgR', where R and R' are hydrocarbon rests
(mostly CH3-, C2H5-) and X anion halogenide, nitrate, sulfide or sulfate).
Dental Amalgams and Hg-Toxicology
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Total amount of answered phone questions
1995-2005 – 82610 questions
7974
8000
6000
6025 6164
6533
9196 9497
8609 8940
7828
6977
4867
4000
2000
Dental Amalgams and Hg-Toxicology
2015/2016
05
20
04
20
03
20
02
20
01
20
00
20
99
19
98
19
97
19
96
19
95
0
19
Počet
dotazů
questions
Phone
10000
57
140
120
100
80
60
40
20
0
134 128
125 127
106
49
60
78
70 75
24
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
20
05
questions
Phone
Počet
dotazů
Total amount of answered phone
questions on “mercury” - 976
Dental Amalgams and Hg-Toxicology
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58
2.00
1.64
1.50
1.50
1.23
0.97
1.00
0.50
1.07 1.07
1.36 1.34
0.98
0.81
0.49
0.00
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
20
05
questions
Phone
Procento
dotazů na rtuť
Percentage of answered phone
questions on “mercury” – 1.13 %
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Limits
Normal level in urine:
3-7 g.l-1
Biological limit in urine (for workers):
260 g.l-1
(0.056 µmol/mmol of creatinine)
Normal level in blood:
4 - 10 g.l-1 (20 - 50 nmol.l-1)
(upper limit in Czech Republic not given, in GB 9 g.l-1, in
USA 15 g.l-1)
In case of acute intoxications
> 95 g.l-1
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Standards
Maximal allowed concentration:
Average:
0.05 mg.m-3
One shot:
0.15 mg.m-3
1 m3 of air saturated by mercury vapors contains (at given
temperature) :
0°C
2 mg Hg
20°C
14 mg Hg
100°C
2 420 mg Hg
Acute toxicity:
Metal
8-10 ml, 20 ml, 50 ml …
Vapors
1.2 - 8.5 mg Hg/m3
Hg2Cl2 (white precipitate, calomel) LD 2 - 3 g p.o., without diarrhoea
(below 1 g).
in children even LD 0.4 g.
HgCl2(sublimate)
LD 0.2 - 1g p.o.
HgI
less toxic
Hg(NO3)2.2H2O
0.4 – 2 g p.o.
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Metallic mercury
T- toxic; N - Dangerous for the environment
R-sentences:
R 23 – Toxic by inhalation
R 33 – Risk of cumulative effects
R 50/53 – Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic
environment
S-sentences:
S (1/2) – Keep locked up and out of the reach of children
S 7 - Keep container tightly closed
S 45 - In case of accident or if you feel unwell, seek medical advice immediately (show label where
possible)
S 60 - This material and/or its container must be disposed of as hazardous waste
S 61 - Avoid release to the environment. Refer to special instructions safety data sheet
- LD50, p.o., rats (mg.kg-1):
Data are not available
- LD50, dermal, rat or rabbit (mg.kg-1):
- LC50, inhalation, rats, a;erosols or particles:
- LC50, inhalation, rats, for gases or vapors (mg.l-1):
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Metallic mercury – per os
- Up to 8-10 ml, 20 ml insignificant, according to
some authors metallic mercury p.o. is totally
non-toxic (it is not soluble in stomach, in HCl)
- Higher amounts could invoke symptoms of chronic
poisoning (including nephritides?), probably.
- Amount of mercury from thermometer is (from the
toxicological point of view) totally insignificant
(Danger can be glass from the thermometer).
- Sticking in appendix
- Embolism in lungs
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Metallic mercury - intravenously
• After i.v. application (injection) of metallic mercury –
embolisation of small drops in circulation, especially
in lungs, eventually of larger drops in hearth (proved
using X-rays).
• If patient does not die in shock, he survives without
any problems probably.
• Attempted suicides - i.v. injection applications of
metallic mercury described in literature (e.g., 2 ml i.v.,
i.e., 27 g) – any symptom of poisoning for many years,
till death (from another reason), embolisation of Hg in
lungs, levels of Hg in hearth, subj. without
complications, without
shock.
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Suicide by elemental mercury
A 21-year-old dental assistant attempted suicide by injecting 10 ml (135 g) of elemental mercury (quicksilver)
intravenously. She presented to the emergency room with tachypnea, a dry cough, and bloody sputum. While breathing
room air, she had a partial pressure of oxygen of 86 mm Hg. A chest radiograph showed that the mercury was distributed in
the lungs in a vascular pattern that was more pronounced at the bases. The patient was discharged after one week, with
improvement in her pulmonary symptoms. Oral chelation therapy with dimercaprol was given for nine months, until the
patient stopped the treatment; the urinary mercury level did not change during this period. At follow-up at 10 months, she
was healthy, with none of the renal, gastrointestinal, or neurologic effects that can result from the oxidation of mercury in
the blood and consequent exposure of these organ systems. The abnormalities on the chest radiograph were still apparent.
Although these abnormalities are striking, the absence of clinical toxicity in this patient illustrates the differences in the
acute and chronic effects of exposure to elemental mercury, inorganic mercury (e.g., mercuric chloride), and organic
mercury (e.g., dimethylmercury). Inorganic and organic mercury are much more toxic than elemental mercury; for example,
a dose of 400 mg of mercury in the form of dimethylmercury is usually lethal.
Elemental Mercury Embolism to the Lung, Francisco Gutiérrez, M.D., and Lucio Leon, M.D. N Engl J Med 2000;
342:1791
Metallic mercury - Percutaneous
• Percutaneous poisoning: fine dispersed metallic mercury, e.g., from
grey unguent (Ung. cinereum), or in other unguents, can be
absorbed from large skin area during repeated applications –
symptoms of chronic poisoning or of sub-acute poisoning.
Metallic mercury – hypodermatic,
intramuscularly
Remains in fat tissue mostly, it is released slowly and according
to the deposited amount can invoke chronic poisoning.
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Metallic mercury – Vapors - Inhalation
• Inhalation of Hg vapors by lungs is practically complete
• In some minutes mercury comes into brain circulation and due to easy
solubility in fats it crosses hematoencephalic barrier and affects
neurotoxically.
• In brain tissue is oxidized to Hg2+ (these ions cross hematoencephalic barrier
back only less intensively)
• =>they accumulate in cortex and basal ganglions
• In erythrocytes (etc.) mercury is transformed using catalase to Hg2+, these
ions are distributed into tissues and they interact with –SH groups of
enzymes
• The highest depo in kidneys, mostly in adrenals. Kidneys reacts by
production of metallothioneins (MT) – proteins containing cysteines, to
which mercury is bounded, damage of kidneys after their saturations –
proximal tubulus, glomerulus, nephro-toxic syndrome
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The thiolic groups (-SH), present in molecules forming dissolved organic carbon
(DOC), are important for irreversible binding of mercury. These groups are present
first of all in hydrophobic fractions of dissolved organic mass (DOM) in humine acid,
fulvo acids in nature and glutathione, cysteine, enzymes, peptides in human body.
Dissociation constants (log K) of mercury complexes with molecules
(groups) contained in DOC in comparison with log K of mercury in
common complexing agents
H  . A
KA 
Ligand
LogKHgL
LogKHgL2
HA
  
Glycine
10.3
19.2
Cysteine
14.4
-
Thiourea
11.4
22.1
21.5; 23.1
-
25.7
-
Glutathione
—
30.7
Diethyldithiokarbamate
—
33.4
Sulfide
—
37.7
34.5
43.8
EDTA
Thiosalicylic acid
Thioglykolic acid
Humine acid. (Suwannee River)
26.1-32.2
Dental
Amalgams and Hg-Toxicology
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waters
2015/2016
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68
Amalgams
„Dental fillings are fully non-toxic.
Free mercury in amalgam cannot be found after 7-10
days after filling preparation“
• There has been described some light chronic
mercury intoxications by dentists after long-term
careless handlings with amalgams in the literature
(preparation of amalgam in fingers, mercury is
absorbed through pores in skin).
Dangers:
1) In crematory by combustion of corpses
2) In underdeveloped countries, gold mining (gold ore is mixed
with mercury and it forms amalgam, is burned in fire and
mercury is released)
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Evidence of mercury poisoning
• Mercury in blood – evidence of recent exposition,
acute poisoning
• Mercury in urine – probably chronic intoxication
(the levels varied during one day)
• Proteinuria (at first low molecular proteins, β1, β2
microglobulins, N-acetylglucosamidase, retinolbinding protein)
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Clinical picture of chronic
After absorption (metallic orpoisoning
contained in soluble salts):
• Ginglivitis: ginglivitis, salivation, shedding of teeth
• Tremor: fine, later pronounced, at the start of limbs only (script), later eyelids,
lips, loss of control of voluntary motions with disturbances of walking
• Erethism: toxic organic psychosis - scrupulosity, shyness, nervousness,
disputatiousness, emotional liability, memory errors, concentration errors,
inversion of sleeping rhythm, depressions, IQ decrease, sometimes symtoms
similar to schizophrenia
• Less frequently kidney failure: tubular lesion, glomerular lesion
Treatment
• EDTA
• DMPS (dimercaptol propane sulfonate-Dimaval)
• Dimercaptol (BAL)
• Hemodialysis (in caseDental
of anuria)
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Inhalation
Acute poisoning
 Cough, breathlessness, febricity, expectoration with blood in case of pneumonic edema
Hg2+per os









Immediately after application burning pain in neck, contractions, white-cinereous coloring of oral
cavity and stained skin
In a few minutes, sometimes in 30 minutes, vomitus, often with blood and peaces of mucous
membrane (death in shock can come in a few minutes or hours) (sometimes vomitus saves the life),
strong pain in epigastrus, later in the whole abdomen, metallic taste in mouth, salivation, thirst; in
oral cavity and in larynx red, reddish areas.
Intensive diarrhoea, often bloody, tenesmus, event. convulsions, looses of NaCl by vomitus and by
diarrhoeas - diarrhoeas with scraps of enteric mucous membrane,
Collapse – accelerated, weak pulse, weak breathing, decrease of blood pressure, after application of
large amount or late started therapy often death in shock in first 24 - 26 hours, sometimes sooner –
in a few minutes or hours
If the patient survives shock - symptoms of the second phase of the poisoning from the second
day:
stomatitis, sometimes very complicated ulcerous (formation of Hg – necrosis – secondary infection)
Proteinuria
Insufficiency of kidneys - Death usually in uremia.
1 - 5 % solution of HgCl2 (mercury (II) chloride) causes dermatitis on the skin. More
concentrated solution evoke vesicles and ulceration.
In case of eye contaminationDental
ulceration
of conjunctiva,
and cornea eventually.
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Treatment of Hg2+per os
• Milk or glair (egg white) or both; patient vomits it spontaneously or it is necessary to evoke
vomiting by mechanical irritation of back wall of pharynx; this procedure can be repeated –
even when patient vomits immediately after intoxication, because formation of precipitate
albumin with Hg is slower, this reaction is reversible and therefore mercury could be
released from precipitate, and therefore this precipitate cannot stay in stomach; Vomiting can
be evoke only when tract is not etched.
• p.o. 50 - 100 ml "antidote metallorum Sauter" - stabilized solution of sulphan it
precipitates Hg in stomach, afterwards it is necessary to evoke to evoke vomit.
• Sodium formaldehyde sulfoxalate - 10 g in glass of water p.o., which reduce Hg2+ ion to less
toxic and soluble Hg+ ion + metallic Hg, then to vomit.
• BAL 5 % solution p.o. 3 ml in milk.
• BAL i.m. (Dicaptol or Dimercaprol inj. á 100 mg in 1 amp.)
• Hydrate of sodium salt of 2,3-dimerkaptopropane-1-sulfonic acid - Unithiol, Unitiol
• D-Penicilamin 1 g i.v.
All treatments are most effective 10 to 15 minutes after intoxication - HgCl2 is absorbed very fast.
Gastrolavage must be performed very carefully (if the interval between mercury application is not
too long and the tract is not etched)
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Most frequent cases – mercury generally
• Patient gave, probably accidentally, into coffee HgCl2 instead of sugar. He
works in pharmacy.
• Broken thermometer (measuring device) and dispersed drops in a closed
room.
• Broken thermometer in rectum or skin injuring, thermometer perforated gut
and mercury stayed in gluteal muscle
• A woman drunk (by mistake) 20 mL of liquid mercury.
• A child swallowed up small round battery (1 % of metallic mercury).
• A man was brought by police into hospital. His wife gave to this man
mercury from thermometer to the meal.
• A man found 5.15 g of mercury in roll (croissant) in form of small drops.
• Consumed drops of mercury from tea, which was stirred by mercury
thermometer
• A man measured the oil temperature for frying by mercury thermometer, this
exploded and some drops were found in oil.
• A questioned woman destroyed mercury thermometer during cookies baking
and on some pieces stayed mercury drops. Can she be intoxicated?
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Interesting questions (1)
[17. 12. 2003 13:35]
[woman, adult, age 55]
Woman, 55, former assistant chemist from Institute of
inorganic chemistry, she is for a few years in disability
pension (due to hepathopathy and neuropathy). The
complications started 27 years ago. This woman
remembers that under her worktable pool of mercury was
discovered (it was found by the exchange of this table).
Question on possibility of chronic poisoning from
mercury vapors and possible symptoms. Hepathopathy
was observed first time during her pregnancy and
neuropathy after delivery, in both cases the causes were
not clarified.
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Interesting questions (2)
26.3.1999 20:01
Husband of calling woman, works as research worker in
J. Heyrovský Institute of Physical Chemistry AS CR.
Mercury was placed in his laboratory for one day
(unknown amount, some student worked with it), without
exhausting. Query on toxicity and therapy. No any health
problem was recorded.
She will call again in case of complications.
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The most serious attempts at suicide
1. Date: 14. 1. 2002
• Man, 28 years old
• Injection of 2 ml of metallic Hg (from thermometer) intravenously
• Level of mercury in serum: 62-52-48 (toxic level 35)
In urine: 8-12-32 (toxic level over 150) (unites were not recorded!!!)
2. Date: 7. 9. 2001
• Man, 22 years old
• Injection of 2 ml of metallic Hg intravenously
• Pains in the place of injection, reddish
• Level of mercury in urine: 0.39-0.33 µmol/mol creatinine (0.58
µg/g cre, cca 1 µg/l) – characterized as practically negative
3. Question: 18. 6. 1996
•
•
•
Woman, 18 years old, drug-user (anonym)
Application of mercury from thermometer paravenously instead of i.v.
(3 months ago) into the hand
The hand pains, tingles.
The place of injection is corny and round
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Categories (questions 1995-2005)

Accident
 Wrong application
 House work
 Mistake
 Aggression
 Medicinal
 Therapeutic mistake (by laymen)
 Professional
 Unknown
 Accident
 Suicide
Subcategories








Injuring
Per rectum
p. o.
Wrong application
Accident
Washing
Aggression
Combination
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Accidents 1995-2004
95
96
97
98 99
Injury
Per rectum
1
5
p.o.
19
31
2
42
00
01
02
1
1
1
03
04 Sum
3
2
54 53
10
54
Wrong
application
80
79
1
73
7
492
4
1
6
Accident
2
2
Washing
1
1
1
2
3
2
5
Aggression
1
Combination
Inhalation
20
3
2
1
3
39
44
57 58
4
3
12
15
2
60
85
95
98
10 566
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79
Attempts at suicide 1995-2004
95
Taking of
non-metal
Taking of
metal
2
96
97
2
2
2
1
1
4
2
4
Injection of
metal
intravenously
98 99
00
5
6
1
Injection of
metal
paravenously
01
02
04 Sum
2
10
1
03
14
8
1
37
1
4
1
2
4
1
7
4
5
6
6
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8
1
56
80
!!!Popular mistake!!!
Question: 19. 7. 1998
It was accidentally given 5 ml of metallic mercury in tank with
water for cattle.
Answer:
I recommend to contact some Hygienic station or some
Environment department, nevertheless, I am convinced that
metallic mercury in water is not danger – Wrong answer
Usually is waste metallic mercury stored under water.
Water column
Mercury vapors concentration 20 cm above water level
[µg.m-3]
0
5
10
400
375
290
Determined 5 minutes after “solution” preparation, laboratory temperature
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Absolute number of reported professional
intoxications by mercury in Czech Republic in
years 1973-2003
Professional
intoxications
by mercury
Professional
intoxications
by mercury
1973
2
1979
1
1974
2
1982
3
1975
3
1987
2
1977
1
1991
1
1978
2
1995
1
Sum
18
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Incorrectness in statistics:
Fears of job loss
Frivolousness
 Absence on preventive investigations
 Dissimulation of symptoms
 Workers with illegal contracts
 People with trade licenses
 Home workers
 Scientific workers
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Liquidation of metallic mercury:
To cover the contaminated place (drops of mercury) with
sulfur, copper or zinc powder; formed amalgam can be
easy replaced by a brush.
Liquidation (cleanup) of Hg2+ solutions
- surface-water sewer, waste channel, garbage, ???
- 0.01 M HgCl2=2,71 g.l-1=> LD ~ 1 dcl
- Standards: drinking water: 0.5 µg.l-1
-
waste water: 50µg.l-1 (daily 100 µg.l-1)
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Literature
1) Databases of drugs, remedies (AISLP, DRUGDEX,
Rote Liste)
2) Toxicological databases (ATDRS, RTECS, POISINDEX,
INCHEM, INTOX)
3) Safety cards
4) Database TEXPRO
5) Database Evidence 1995-2006
6) Zdravotnická statistika. Nemoci z povolání a profesionální
otravy. ÚZIS ČR
7) Houserová P. a kol.: Chemical forms of mercury in aqueous
eco-systems - characters, levels, circulation and
determination. Chem.
Listy 100, 862-876 (2006).
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