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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 249

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MERCURY USE: DENTISTS

Dental amalgam is an alloy that results from the trituration of powdered

silver, tin and copper which hardens quickly to a solid phase. Dental

amalgams have been used as the main restorative in teeth for more than

150 years; it is a popular restorative material because it can be easily

manipulated and is relatively inexpensive.

Amalgam wastes are generated from amalgam abrasion, from the

placement or replacement of fillings, and from cremation. The Western

Lake Superior Sanitary District has estimated that dentists emit 0.1

grams of mercury per day per dentist. The approximate 1,650 dental

offices in the metropolitan Seattle, Washington area contribute an

estimated 14 percent of the mercury in that system. San Francisco has

estimated that 12 percent of the mercury contributed to that city’s

system comes from dental offices. (directly from the concern over

mercury and wastewater, journal of MDA) It has been estimated that

approximately 4 percent of the mercury entering the Lake Superior

ecosystem is from amalgam wastes.

Alternatives to mercury-amalgam fillings exist, but are not appropriate in

all cases or for all patients. Until acceptable alternatives exist for every

situation, mercury will continue to be used widely in dental practices. It

is imperative that dentists handle the mercury in their office carefully to

prevent releases of mercury to the environment.

There are specific steps dentists can take to reduce their mercury

releases. They may consider the use of precapsulated amalgam alloy

instead of the use of bulk liquid mercury; the precapsulated amalgam

can lessen the overall amount of mercury being used and decrease spills.

Dentists may also consider the use of chair side traps to capture their

waste mercury-amalgam and can recycle this waste.

Table of Contents

About This Handout ........................... 250

Why Should I Be Concerned About

Mercury? ............................................. 251

Facts About Mercury Amalgam ......... 253

Capturing Amalgam and Mercury

Wastes.................................................. 253

Procedures for Collecting Mercury and

Mercury Amalgams ............................ 254

Keeping Mercury Out of Medical Waste

Incinerators ........................................ 257

Keeping Mercury Out of the Solid Waste

Stream ................................................. 257

Keeping Mercury Out of the WasteWater

Stream ................................................. 257

Amalgam Recyclers ............................ 258

Mercury Recyclers .............................. 258

Star Program: Detroit ....................... 259

Alternatives to Mercury Amalgam

Fillings ................................................ 259

Amalgam Use & Alternatives ............ 260

What About the Health Effects of MercuryAmalgam Fillings? ............................. 261

What We Can Do as a State ............... 261

Dental Use of Amalgam: Activities in

Other Countries .................................. 262

Other Mercury-Containing Products that

May be Found in a Dental Office ....... 263

Mercury Product Focus: Detergents and

Cleaners .............................................. 263

Mercury Product Focus: Lamps ....... 264

Mercury Product Focus: Switches..... 266

Mercury Spills..................................... 268

Action Ideas for Dentists .................... 269

Sample Proclamation ......................... 270

Bibliography ....................................... 272

More Articles About Mercury-Amalgam

Fillings ................................................ 279
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250 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

ABOUT THIS HANDOUT

This is one chapter of the “Wisconsin Mercury SourceBook.” The

Sourcebook was written as a guide for communities to help identify and

reduce the purposeful use of mercury. The SourceBook contains

background information on mercury contamination and provides a sevenstep outline for drafting a mercury reduction plan.

This handout is one of the nineteen sectors that were highlighted in the

SourceBook as a potential contributor of mercury in any given

community.

What you will find in this handout:

 ́ Information on mercury-containing products and that are unique to

the agriculture industry

 ́ Action ideas that describe pollution prevention, recycling, and

management practices for a mercury reduction plan for a business in

this sector. This provides a good overview of the types of mercurycontaining products and alternatives that may exist in your sector.

 ́ Current mercury projects in the agriculture industry

For more information, please contact:
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 251

WHY SHOULD I BE CONCERNED

ABOUT MERCURY?

The good news is that the majority

of products that use mercury

purposefully have acceptable

alternatives. For example, electric

vacuum gages, expansion or

aneroid monitors are good

alternatives to mercury blood

pressure monitors. Mechanical

switches, magnetic dry reed

switches, and optic sensors can

replace mercury tilt switches.

Replacing mercury-laden products

with less toxic alternatives is

referred to as source reduction.

Source reduction allows us to

eliminate the use of mercury in

certain waste streams. This is

especially beneficial considering

the volatile nature of mercury,

because mercury can so easily

transfer from air to soil to water.

Practicing source reduction in

combination with recycling the

mercury already in the waste

stream can have a significant

impact on reducing mercury levels

in the environment.

Some of you may remember playing with mercury when you were a

child. Its silvery white shimmer was entrancing, and the ability of its

glistening mass to split and come back together again was magical. But

scientists are now beginning to realize that there is another side to

mercury’s wily nature. In fact, it is some of mercury’s most elemental

qualities that make it a difficult substance to handle.

Mercury is a common element that is found naturally in a free state or

mixed in ores. It also may be present in rocks or released during volcanic

activity. However, most of the mercury that enters the environment in

Wisconsin comes from human uses.

Because mercury is very dense, expands and contracts evenly with

temperature changes, and has high electrical conductivity, it has been

used in thousands of industrial, agricultural, medical, and household

applications.

 It is estimated that half of the anthropogenic mercury releases in

Wisconsin are the result of the purposeful use of mercury. The other half

of mercury emissions originate from energy production.

Major uses of mercury include dental amalgams, tilt switches,

thermometers, lamps, pigments, batteries, reagents, and barometers.

When these products are thrown in the trash or flushed down a drain, the

mercury doesn’t go away.

Mercury is a bioaccumulative,

persistent, toxic substance that

threatens the health of humans

and wildlife throughout North

America. The USEPA,

Environment Canada, the

International Joint Commission,

the Commission for Environmental

Cooperation and many state and

provincial governments have

identified mercury as one of the

most critical pollutants for

significant elimination and/or

reduction.

SO WHAT’S THE BIG DEAL?

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HEALTH EFFECTS OF

ELEMENTAL MERCURY

The toxicity of mercury has long

been known to humans. Hat

makers during the 19th century

developed symptoms of shaking

and slurring of speech from

exposure to large amounts of

inorganic mercury, which was

used to give a metallic sheen to

felt hats. This gave rise to the term

“mad as a hatter.”

The hat makers were suffering

from neurological damage from

the inhalation of mercury fumes.

Exposure to elemental mercury

vapors can cause acute respiratory

problems, which are followed by

neurologic disturbances and

general systemic effects. Acute

exposure to inorganic mercury by

ingestion may also cause

gastrointestinal disturbances and

may effect the kidneys.
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252 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Mercury can enter the environment from a number of paths. For example, if

a mercury-containing item is thrown into the garbage, the mercury may be

released into the atmosphere from landfill vapors or leachate, or the mercury

may vaporize if the trash is incinerated. If mercury is flushed through a

wastewater system, the mercury will likely adhere to the wastewater sludge,

where it has the potential to volatilize and be deposited elsewhere. Mercury

can enter the atmosphere through these various means because it evaporates

easily. It then travels through the atmosphere in a vaporized state.

Once mercury is deposited into lakes and streams, bacteria convert some of

the mercury into an organic form called methylmercury. This is the form of

mercury that humans and other animals ingest when they eat some types of

fish. Methylmercury is particularly dangerous because it bioaccumulates in

the environment. Bioaccumulation occurs when the methylmercury in fish

tissue concentrates as larger fish eat smaller fish. A 22-inch Northern Pike

weighing two pounds can have a mercury concentration as much as 225,000

times as high as the surrounding water.

These concentrations are significant when one considers the potential toxic

effects of methylmercury. Methylmercury interferes with the nervous system

of the human body and can result in a decreased ability to walk, talk, see, and

hear. In extreme examples, high levels of methylmercury consumption has

resulted in coma or death.

Many animals that eat fish also accumulate methylmercury. Mink, otters,

and loons in Wisconsin have been found to have high levels of mercury in

their tissue. Mercury can interfere with an animal’s ability to reproduce, and

lead to weight loss, or early death.

Mercury Transport and Bioaccumulation

Direct Air Emissions

Solid Waste Disposal

Wastewater Disposal

Incineration

Sludge Land Disposal

M ethyl 

M ercury

M ercury

Fish Consumption

Advisories

There are currently 260 lakes

and more than 350 miles of

rivers in Wisconsin that have

fish consumption advisories

because of mercury.

Approximately 1 out every 3

sites that is tested is listed

on the advisory; no sites

have ever been removed.

Forty-eight states now issue

fish consumption advisories

to protect human health.

Most of these warnings are

related to mercury

contamination.
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 253

CAPTURING

AMALGAM AND

MERCURY WASTES

Because mercury amalgam fillings

are the material of choice for

many fillings, it is important to

capture and dispose of this waste

safely and effectively. There are

several filtration devices available

to capture amalgam at the source

of generation. These include “low

tech” devices such as sieves and

strainers, and “high-tech” devices

such as sedimentation columns,

centrifuges, and complete capture

units. (M2P2)

There are a range of options

available for handling amalgam

wastes. The board of trustees of

the ADA have identified the

following (1994 supplement to

annual reports and resolutions):

◆ lowest tech: filters (secondary

screens with finer mesh sizes,

if technically practical)

◆ low tech: holding tanks (if

prototypes are made

commercially available)

◆ high tech: separators (the

commercially available models,

e.g., from Europe)

◆ higher tech: electrical and

chemical approaches (which

could address all of the

discharge and not just the

particulate)

◆ amalgam alternatives (would

still need to address removals

of existing amalgams)

◆ closed systems (if feasible)

Research by the University of

Illinois, Chicago has shown that

60% of the mercury from a

dental practice is captured on

commonly used chair-side traps.

The remaining portion settles out

rapidly; less than 1 percent

remains in the water after settling

for 24 hours. Therefore, the

recycling of amalgam captured

on disposable trays is an

effective way of keeping

mercury out of the environment.

The Western Lake Superior

Sanitary District (WLSSD) reports

that the cost of recycling chair side

traps is approximately $3.50 per

pound, probably less than $20 per

year per practice. Recycling the

amalgam is much less restrictive

than managing waste as a RCRA

hazardous waste.

Facts About Mercury Amalgam

from DWSD

✔ Amalgam has been used extensively as tooth-filling material

for more than 150 years

✔ The toxic effects of silver/mercury dental fillings have been

discussed and debated in professional circles since mercury’s

introduction into dentistry in 1819

✔ Components of dental amalgam are: mercury, powdered

metals, silver, copper, zinc, and tin

✔ In the past 50 years, about 75% of all direct restorations

placed were of amalgam

✔ Amalgam waste is created when fillings are removed or

replaced

✔ Particles of removed old amalgam restorations, smaller than

the filter size hole, are normally lost to the sewer unless the

dentist has a high efficiency filtration or separation device in

place

✔ Dentists estimate that 27% of old amalgam restorations are

lost to the sewer system
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254 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

PROCEDURES FOR COLLECTING MERCURY AND

MERCURY AMALGAMS

From the Michigan Dental Association, “HHR Update,” March 1996 + WLSSD handout

In order to reduce the amount of mercury from amalgam particles entering the sewer system or landfill, it is

recommended that you use an amalgam trap.

Disposable Traps

Information from WLSSD

Recycling facilities recover mercury from amalgam or amalgam traps for recycling. The following techniques

will properly collect, store, and transport the chair-side traps to a recycler. Following these simple procedures,

you can reduce the amount of mercury released to the environment.

1 Flush the vacuum system with line solution before changing the chair side trap. The best method is to

flush the line the last thing before you go home, and then change the trap first thing the next morning.

2

Use barrier techniques such as gloves, glasses, and mask when handling the chair side trap. Choose

 utility gloves intended for cleaning and handling wastes for this procedure.

3

Do not place gloves*, plastic bags, or paper towels into the recycling container. These add the volume

of waste created and cause problems with recycling equipment. Unless saturated with blood, dispose

of gloves, plastic bags, and paper towels in the garbage.

4

A. Chair-Side Traps

Place the trap in widemouth plastic container. Label the container: Amalgam for recycling. Keep the

container covered.

Only traps on chairs used for amalgam placement or removal need special handling. Place

traps from chairs dedicated to hygiene in regular garbage.

B. Vacuum Pump Traps

Reusable Traps: Empty the trap’s contents into a widemouth plastic container. Keep the

container covered.

Disposable Traps: Replace the cover after use. Place the trap in the original box for

shipment to a recycler.

Label the containers: Amalgam for Recycling.

* Please note: “AMALGAWAY” is currently the only company that will take the gloved disposable

amalgam trap. To contact the “AMALGAWAY” mail disposal system contact: AMALGAWAY, 10085

Allisonville Road, Suite 201, Fishers, IN 46038. Or call AMALGAWAY 1-800-267-1467.
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 255

Reusable Amalgam

Traps

First, disinfect the trap for 24

hours using a minimum amount of

disinfectant. Then, remove all

visible amalgam and store it in an

airtight container, labeled “WASTE

AMALGAM.” The disinfected

trap can then be reused. Recycle

the waste amalgam as outlined for

the scrap amalgam.

Secondary Filters on

the Vacuum Pump

Change these filters at least once

a month, or more frequently if

needed. DO NOT dispose of the

filters as regulated medical waste.

Place facial tissue or towels inside

to absorb the liquid.

Scrap Amalgam

Excess amalgam remaining at the

end of a procedure should be

stored in an air-tight container

labeled “SCRAP AMALGAM.”

The American Dental Association

recommends that the scrap

amalgam container be stored

under a small amount of

photographic fixer. Most

reclaimers/recyclers will only

accept dry amalgam, so you may

need to decant off the fixer and

blot the amalgam dry with a paper

towel.

Bulk Mercury

The Detroit Water and Sewerage

Department has estimated that

approximately 10-15% of the

dentists in their area use bulk

mercury and bulk amalgam alloy

for their amalgam restorations.

This correlates with information

from the federal Food and Drug

Administration Dental Products

Panel, which estimates that 8 to

10% of dental mercury an

amalgam alloys are sold to dentists

in bulk form. (DWSD task force for

mercury min from dental facilities,

summary of June 13, 1995 meeting)

Since 1984, the American Dental

Associations’s Council on Dental

Materials, Instruments and

Equipment, as part of its dental

mercury hygiene

recommendations, has recommend

that dentists discontinue the use of

bulk dental mercury and bulk

amalgam alloy and that they only

use precapsulated amalgam alloy

in their practices. The use of these

pre-mixed capsules decreases the

potential of occupational exposure

to mercury by eliminating the

possibility of bulk mercury spills

and leaky dispensers, and can

lessen the overall amount of

mercury being used.

The 1994 American Dental

Association house of Delegates

and the 1995 Michigan Dental

Association House of Delegates

passed a resolution recommending

that dentists eliminate the use of

bulk mercury and bulk amalgam

alloy. The MDEQ (???) has set up

a bulk mercury collection program

for their dental offices and this

project has been met with great

success. They offered three

options for the collection of bulk

mercury from dentists: 1) mail -in

programs 2) drop-off locations 3)

infectious waste haulers take-back

program. We hope to implement a

similar program here in Wisconsin.

Amalgam Capsules

Used, empty amalgam capsules

have been determined to be nonhazardous, based on toxicity test

results. Empty amalgam capsules

can be disposed of with all other

office solid waste in the garbage.

Dispose of Your Waste

Amalgam and Filters

Properly

The Western Lake Superior

Sanitary District audits have

shown that 80% of the traps

used by dentists are improperly

disposed of by placement in

the garbage or in medical

waste bags. Care should be

taken when handling waste

amalgam or waste mercury -

used filters should NEVER be

placed in the garbage or in a

medical waste red bag.
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256 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

New amalgam 

fillings

Surplus of 

triturated 

amalgam

Carved 

surplus of 

amalgam

Minor 

amalgam 

particles 

Collection 

recycling

Drain/sewage

Mercury 

in 

Dental Practices

Removal of old 

amalgam fillings

Lost/extracted 

teeth with 

amalgam fillings

Amalgam fillings 

in deceased 

persons

Waste

Interment

Cremation

central vacuum 

system

sludge

amalgam 

separator

Mercury Cycle in Dentistry

from Horsted-Bindslev et al., 1991
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 257

Keeping Mercury

Out of Medical

Waste

Incinerators

If your amalgam waste or filters are

placed in your medical waste red

bags, the amalgam will be sent to a

Medical Waste Incinerator (MWI).

There are approximately 5,000

MWIs distributed evenly throughout

the United States. MWIs are a large

source of mercury to the

environment. There is up to 50

times more mercury in medical

waste than in general municipal

waste, and the amount of mercury

emitted from general medical

incinerators averages more then 60

times that from pathological

incinerators. In Wisconsin, MWIs

are responsible for approximately

25 percent of air emissions in

Wisconsin that are associated with

the purposeful use of mercury.

Mercury is a very volatile metal that

evaporates easily. When a mercurycontaining product finds its way

into a medical waste red bag and is

incinerated, the mercury becomes

gaseous and exits through

smokestacks into the air. The

mercury then settles on land and in

water where it can be changed into

its organic form, methylmercury.

Fish bioconcentrate the mercury to

such levels that it can harm wildlife

and can be a potential human health

risk. It is very important to educate

employees about the dangers of

putting amalgam wastes in the red

medical waste bags to prevent this

contamination.

Keeping Mercury

Out of the Solid

Waste Stream

If your waste amalgam is placed in

the garbage, it could potentially be

incinerated, and the mercury will

volatilize and enter the atmosphere

as described above. If the solid

waste is sent to a landfill, the

mercury may volatilize out with the

methane gas that is released from

the landfill.

Sewer Pipes

Mercury was used extensively

in medical settings in the past.

Often times the mercury may

have found its way into the

pipes of a dental facility when

items were broken, disposed of,

or spilled. This mercury can

settle at a low point such as a

sump or trap and remain in the

pipes of a dental facility for

many years. Often the slow

dissolution of the mercury in a

sump, trap, or pipe is enough to

cause violations of wastewater

discharge standards even after

poor management practices

have been eliminated. Hot

spots in a dental facility’s piping

may appear where equipment

maintenance areas were

located. Whenever traps or

sumps are moved or cleaned,

the solid contents should be

treated as a hazardous waste

unless proven otherwise. For

more information, please see

the excerpts from the MWRA/

MASCO Infrastructure

Subcommittee Maintenance

Guidebook that appear in the

“Resources” section of this

sourcebook.

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Keeping Mercury

Out of the

WasteWater

Stream

Mercury amalgam that is not

captured by a trap in your office

will travel to your local

wastewater treatment plant. Once

mercury enters the wastewater

treatment plant, most of it

concentrates in wastewater

biosolids during treatment. Since

most treatment plants dispose of

generated solids by land spreading,

mercury enters the terrestrial

environment by this process. Some

of this mercury spread on land

may, over time, be volatilized to the

atmosphere. This mercury may

then be deposited into lakes and

streams, methylated, and ingested

by fish, eventually reaching wildlife

and humans.

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258 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Acme Scrap Iron and Metal

7588 N. Syvania Avenue

Sturtevant, WI 53177

(414) 835-2662

Amalgaway

10085 Allisonville Road, Suite

203

Fishers, IN 46038

(800) 267-1467

Dental Recycling North America

PO Box 1069

Hackensack, NJ 07601

(800) 360-1001

D.F. Goldsmith

909 Pitner Avenue

Evanston, IL 60602

(708) 869-7800

Made Ltd.

Rt. 1 Box 127a

Hillman, MN 56338

(612) 277-3981

Maguire and Strickland Refining

Co.

1290 81st Avenue NE

Minneapolis, MN 55432

(800) 486-2858

Mercury Refining Company, Inc.

1218 Central Ave.

Albany, NY 12205

(518) 459 -0820

Recyclights Inc.

401 West 86th Street

Bloomington, MN 55420

(800) 831-2852

Mercury Waste Solutions, Inc.

21211 Durand Avenue

Union Grove, WI 53182

(414) 878-2599

Bethleham Apparatus

890 Front Street

Hellertown, PA 18055

(215) 838-7034

Garfield Refining

810 East Cayuga

Philadelphia, PA 19124

(800) 523-0968 ext. 300

Inmetco

PO Box 720

Elwood City, PA 16117

(412) 758-5515

Mercury Refining Company

790 Wateruliet-Shaker Rd.

Latham, NY 12110

(800) 833-3505

Mercury Waste Solutions, Inc.

21211 Durand Avenue

Union Grove, WI 53182

(414) 878-2599

AMALGAM

RECYCLERS

MERCURY

RECYCLERS
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 259

Alternatives to mercury amalgam

include gold, ceramic, porcelain,

polymers, composites and glass

ionomers. The cold silver and

gallium techniques are among the

most promising currently in the

developmental phase.

However, while alternatives exist

for mercury amalgam, they have

limited uses. Some of the variables

effecting the choice of material

are the location of the defect in the

tooth, the extensiveness of the

defect, the location of the afflicted

tooth in the mouth, the amount of

stress placed on the filling, and the

probability for contact with

moisture during placement of the

filling material. Amalgam use is

favored over composite resins by

STAR PROGRAM: DETROIT

From the Journal of the Michigan Dental Association, April/May 1995

The Detroit Water and Sewerage Department (DWSD) is a large municipal utility that supplies both drinking

water and wastewater treatment services to millions of individuals and industries in southeastern Michigan.

The DWSD has initiated a pilot program for dental facilities which seeks to reduce or eliminate mercury use

and improve disposal practices within dental offices. The pilot program has multiple objectives:

✯ to identify mercury usage and disposal practices among dentists

✯ to quantify the amount of mercury entering the sewage system from this source

✯ to identify and encourage the use of mercury-free alternatives and other suitable technologies

within the field

✯ to develop materials and other outreach initiatives specifically designed for the dental profession.

The DWSD has compiled a survey of over 2,000 dentists and conducted site surveys as well. They have also

convened a task force that will explore ways of reducing mercury pollution from dental facilities, make

recommendations for future legislation, regulation, and enforcement, and develop prevention strategies.

differences in strength durability,

ease-of-placement, an the lower

cost between mercury amalgam

and alternatives. Amalgams resist

dissolution and wear better, require

a less precise technique during

placement, and are lower in cost.

However, 0.6 percent of the

population may have some risk to

mercury amalgams due to a

mercury sensitivity. (research from

canadian dental association on

dental amalgam, published in

journal of american dental

association, Vol 122, August 1991,

pg. 54)

Mercury use by the dental

profession decreases each year

due to fluorides, sealant use,

improved oral hygiene practices

and dietary modifications. This

results in fewer fillings removed

from patients. In fact, in the

United States, from 1979 to 1990,

a 38 percent reduction in the use

of dental amalgam for restorative

procedures has been observed.

Some people are predicting that

technological advances will allow

amalgam substitutes to become

competitive and replace amalgam

fillings in the next couple of

decades. However, because a

large segment of the population

currently has mercury amalgam

fillings, the proper handling of this

waste will be a relevant issue for

some time to come.

ALTERNATIVES TO MERCURY AMALGAM FILLINGS

(from M2P2)
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260 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Dental Amalgam Use and Alternatives

Adopted from Dental Amalgam: A Scientific Review and Recommended Public Health Service Strategy for Research, Education, and

Regulation, Dept. HHS, January 1993. As appeared in Mercury Pollution Prevention In Michigan, April, 1996

Critical

Parameters

in Evaluating

Posterior

Restorative

Materials

Amalgam Composite Glass

Ionomer

Gold Foil Gold Alloy

(Cast)

MetalCeramic

Crowns

Median

Longevity

Estimate

8 to 12 years 6 to 8 years No data1: 5

years predicted

No data: 10 to

15 years

estimated

12 to 18 years 12 to 18 years

Relative

Surface Wear

Wears slightly

faster than

enamel

Excessive wear

in

stress-bearing

situations

Excessive wear

in

stress-bearing

situations

Excessive wear

in

stress-bearing

situations

Wears similar

to enamel

Porcelain

surface may

wear opposing

tooth

Resistance to

Fracture

Fair to

excellent

Poor to

excellent

Poor Fair to good Excellent Excellent

Marginal

Integrity

(leakage)

fair to excellent

(self-sealing

through

corrosion

products)

Poor to

excellent

(polymerizatio

shrinkage can

cause poor

margins)

Poor to

excellent

Poor to

excellent

Fair to good

(depends on fit

and type of

buting agent

used)

Poor to

excellent

(depends on fit

and type of

buting agent

used)

Conservation

of Tooth

Structure

Good Excellent Excellent if

initial

restoration,

not if

replacement

Good Poor Poor

Esthetics Poor Excellent Good Poor Poor Excellent

Indications:

Age range

Occlusal

Stress

Extent of

caries

All ages

Moderate stress

Incipient to

moderate size

cavity

All ages

Low-stress

bearing

Incipient to

moderate size

cavity

All ages

Adult-class V

and low-stress

primary teeth

Class I and II

child incipient

to moderate

size cavity

Adult

Class III and V

and Crown

repair

Incipient to

moderate size

cavity

Adult

High-stress

areas

Severe tooth

destruction

Adult

High-stress

areas

Severe tooth

destruction or

aesthetic

considerations

Cost to

patient2

1X 1.5X 1.4X 4X 3X + gold 8X

1 Longevity estimates reflect from published studies, however, under different clinical situations many restorations will last longer. For

materials that have emerged in the last decade and gold foil, estimates are speculative.

2 Relative cost to patient, in relation to amalgam (1X). There may also be considerable geographic variation.
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 261

WHAT ABOUT THE HEALTH EFFECTS OF MERCURYAMALGAM FILLINGS?

The focus of this analysis revolves around the proper disposal of amalgam filling waste, and not the potential

health effects of its use as a restorative material. However, because this issue frequently comes up when

discussing the use of mercury amalgams, we have provided a brief discussion of the issue and a list of paper

abstracts on the subject. (The abstracts appear in the appendix.)

In general, the american dental community regards mercury-amalgam fillings as safe. The U.S. Public Health

Service issued a report in 1993 stating that there is no health reason not to use amalgam, except in the

extremely rare case of the patient who is allergic to a component of amalgam. This stance has been echoed by

the Food and Drug Administration, the National Institutes of Health Technology Assessment Conference, and

the National Institutes of Dental Research, all who support dental amalgam as a safe and effective restorative

material.

Nonetheless, the issue is certainly under debate. There are two sections of articles included in the appendix

about this issue.

What we can do as a State

Following Michigan’s lead, Wisconsin can implement some practical initiatives to help reduce mercury

entering waste water treatment plants from dental offices. Here are some ideas from the Michigan

Dental Association and the Michigan Mercury Pollution Prevention Task Force:

◆ Encourage the development and use of mercury amalgam alternatives

◆ Recommend the elimination of bulk mercury and bulk amalgam alloy; recommend the use of

precapsulated amalgam alloy only

◆ Participate in a bulk mercury collection program

◆ Develop and distribute a pamphlet on amalgam waste reduction and recycling

◆ Provide a Health and Hazard Regulation Traveling Seminar on all phases of mercury hygiene in

dental offices. (These seminars are part of a continuing education program that is mandatory for all

Michigan licensed dentists.)

◆ Include articles in Dental Association Journals

◆ Speak at local dental society meetings

◆ Research particle size distribution on the latest in amalgam separators

◆ Form a Dental Task Force on Mercury Minimization

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262 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

DENTAL USE OF

AMALGAM:

ACTIVITIES IN

OTHER

COUNTRIES

Info from John Gilkeson

Canada

Canadian Ministry of Health has a

web site. Access this site through

http://hpb1.hwc.ca/datahpb/

dataehd/ Then click on

“English.” When you get the next

screen, click on “Medical

Devices.” Next screen, click on

“Research and Surveillance.” The

“Health Canada Position

Statement on Dental Amalgams”

and “The Safety of Dental

Amalgams” provide a summary of

Health Canada’s take on the issue

and of a recent Health Canadasponsored study of amalgam

safety.

This study that found that for the

average Canadian, 50 percent of

daily exposure to mercury (50

percent of the amount absorbed by

the body) is attributable to releases

from amalgam fillings. That

makes amalgam the most

significant single source of

mercury exposure for the average

Canadian. [Please note: The

summary of the report doesn’t

distinguish between forms of

mercury—exposures to

methylmercury in fish may still

cause greater health risk.]

However, the report concluded

that exposures at this level do not

cause illness in the general

population, although a small

percentage of the population has

allergic hypersensitivity to mercury

that could be triggered by

exposure through amalgam.

The study also developed a

tolerable daily intake (TDI) value

for mercury (something that

Health Canada does not endorse).

This is a level of mercury

exposure considered to be safe—

with a safety factor of 100. Most

people’s exposure are below this

TDI, although people who have

seven or more amalgam fillings

would have exposures in excess of

the TDI. Because of the safety

factor, it is still unlikely that such

people are at risk of health effects.

Health Canada’s position

statement says that neither a ban

on amalgam nor removal of sound

amalgam fillings from healthy

patients is justified. However, it

recommends use of non-mercury

materials in the primary teeth of

children, when “suitable,” and

recommends against the using

amalgam with pregnant women

(due to exposures during the filling

procedure) and with patients who

have impaired kidney function.

Sweden

Recently obtained information

from Sweden indicates that use of

amalgams in children has been

discontinued and use in adults is to

be discontinued as of Jan. 1, 1997.

This decision has been made on

the basis that there is simply too

much mercury in the environment

already, and amalgam use is halted

like nearly all other uses. They

have stayed away from the health

issue because it is contentious and

currently unresolved, due to the

lack of research that can be

agreed to resolve the question.
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 263

OTHER MERCURY-CONTAINING PRODUCTS THAT

MAY BE FOUND IN A DENTAL OFFICE

Mercury Product

Focus: Detergents

and Cleaners

The Massachusetts Water

Resources Authority (MWRA), in

conjunction with MASCO (a

consortium of Longwood Medical

and Academic Area Institutions),

has been working with their area

hospitals and academic institutions

to identify and address the problem

of mercury contamination in

hospital and medical waste

streams. As part of this process,

the MWRA group also worked to

identify “other sources” of

mercury contaminants. These are

common products, such as bleach,

alcohol, laboratory lids, not

otherwise thought to be of

significant importance or concern,

that might contain low levels of

mercury. Thus far, a total of 118

products has been identified by this

team. This information is

applicable in a variety of settings.

Included among their findings:

✯ At least four (4) cleaners, nine

(9) soaps, embedding tissues

and other miscellaneous items

such as photoprocessing fixer

and developer solutions each

contain significant levels of

mercury.

“Other Sources of Mercury”

Information from the Massachusetts Water Resources Authority/MASCO

Product Mercury Content

(ppb)

Ajax Powder 0.17

Comet Cleaner 0.15

Lysol Direct <0.011

Soft Scrub <0.013

Kodak Fixer 6.9; 3.7

Kodak Developer 2.65; 6.0

Alconox Soap 0.004 mg/kg

0.005 mg/kg

<0.0025 mg/kg

Derma Scrub <5.0

<2.5

Dove Soap 0.0027

Ivory Dishwashing

Liquid

0.061

Joy Dishwashing

Liquid

<0.01

Murphy’s Oil Soap <0.012

Soft Cide Soap (Baxter) 8.1

Sparkleen Detergent 0.0086

Sunlight Dishwashing

Detergent

<0.011
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264 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Mercury Product

Focus: Lamps

✔ fluorescent

- general purpose

straight, U-bent,

circline, compact

- high output

✔ germicidal lamps

- cold cathode

- hot cathode

- slimline

✔ metal halide

✔ high pressure sodium

There are a number of electric

lamps that use mercury as an

intrinsic part of their functioning.

These lamps include fluorescent,

mercury vapor, metal halide, and

high pressure sodium lamps. These

lamps may be used indoors or

outdoors in heat lamps, film

projection, photography, dental

exams, photochemistry, water

purification, or street lighting.

Fluorescent lamps contain mercury

in a vapor form. The electric

current of the lamp “excites” the

mercury atoms, which then give

off invisible ultraviolet light. The

ultraviolet light then “excites” a

powdery phosphorus coating inside

the tube that emits visible light.

The mercury that is contained in

these lamps is emitted into the

atmosphere when the lamps are

broken, disposed of in landfills, or

incinerated.

Fluorescent lamps are still a good

option. They last longer and cost

less to run than incandescent lights

because they use up to 50 percent

less electricity. This energy

savings helps reduce mercury

emissions because small amounts

of mercury are present in coal that

is burned in power plants. The less

energy we use, the less mercury

will be released into the

environment when coal is burned.

New Low Mercury Fluorescent Lamp

Phillips Electronics has developed a long-life fluorescent that contains so little mercury it is no longer

considered a hazardous waste. “Typically fluorescent lamps have an overabundance of mercury

because mercury loses its effectiveness due to physical and chemical reactions. So manufacturers

put in an overdose of mercury to compensate for these reactions,” said George Preston, a scientist at

Philips Lighting Co. Currently, a four-foot lamp contains about 22.8 milligrams of mercury, down

from 38.4 milligrams in 1990. Philips’s new lamp contains less than 10 milligrams of mercury. The

new lamp, named ALTOTM, relies on a “buffering mechanism” that blocks the physical and chemical

reactions that cause the mercury to lose its effectiveness over time. The lamp also uses a new form

of phosphorus patented by Philips.

- From “Philips Unveils a Fluorescent Lamp With Less Mercury and a Long Life,” Wall Street Journal, June 9, 1995

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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 265

Several Wisconsin companies are

in the business of recycling

fluorescent lamps and

incandescent bulbs. The copper

coils, and aluminum or brass end

pieces are smelted and reused as

raw materials for non-food

products. The glass can be purified

and used to make fiberglass. The

mercury is distilled from the

phosphor powder and reused in

new lamps and thermometers.

State hazardous waste regulations

prohibit businesses from disposing

of waste lamps and light bulbs in

sanitary landfills if those lamps and

bulbs contain levels of heavy

metals that exceed hazardous

waste limits. For information on the

storage, collection, and transport of

fluorescent lamps, please see the

informational handout, “Recycling

Your Fluorescent Lamps,” in the

“Resources” section of this

sourcebook.

Recycling Your Fluorescent Lamps

Types of Bulbs and Lamps that Contain Mercury

◆ Fluorescent Lamps - the tube-style were first used as overhead lighting in

offices, now they also come in compact globe shapes for a variety of home and

office uses

◆ Mercury Vapor Lamps - the first high intensity discharge (HID) lamps with

blue-white light, originally used as farmyard lights

◆ Metal Halide Lamps - newer, more efficient HID lights found in homes and

offices

◆ High-Pressure Sodium Vapor Lamps - white-yellow HID lights used for

street lamps and outdoor security lighting

◆ Neon Lamps - brightly colored lamps typically used in advertising; most colors

contain mercury except red, orange, and pink

- From the Wisconsin Recycling Markets Directory
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266 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Mercury Product

Focus: Switches

Tilt switches

✔ silent light switches (single

pole and three way;

discontinued in 1991)

✔ fire alarm box switch

✔ temperature control (mounted

on bimetal coil or attached to

bulb device)

✔ thermostats

· room temperature

control

· refrigerators

Another source of mercury that

dental facilities may encounter is

mercury switches. A small

electrical switch may contain 3,500

milligrams of mercury; industrial

switches may contain as much as

eight pounds of mercury. Mercury

is used in temperature-sensitive

switches and in mechanical

switches. The mechanical (tilt)

switches are activated by a

change from a vertical to a

horizontal position. These are used

in products like thermostats and

silent switches. Mercurycontaining tilt-switches may also

be present in or under the lids of

clothes washers and chest

freezers - they stop the spin cycle

or turn on a light. Mercury tilt

switches are also found in motionsensitive and position sensitive

safety switches in clothes irons or

space heaters. If a mechanical

switch is not visible in these items,

a mercury switch is probably being

used.

Mercury tilt switches have been

used in thermostats for more than

40 years. According to Honeywell,

Inc., a major manufacturer of

thermostats, more than 50 million

mercury-containing thermostats

have been sold since the 1950s for

use in homes and offices. Mercury

in these thermostats provide

accurate and reliable temperature

control, require little maintenance,

and do not need a power source.

However, each mercury switch in

a thermostat contains about 3

grams of mercury. (There may be

one or more of these switches in a

single thermostat, each switch in a

sealed glass bulb.) Alternatives to

these products include electronic

thermostats, which can be

programmed to set room

temperatures at predetermined

times. (blue brochure: the waste

connection)

Float control switches may be

used in septic tank and sump

pumps to turn the equipment on

and off when water is at a certain

level. Often, these switches are

visible. Temperature-sensitive

switches may be used in

thermostats. Yet another type of

mercury switch, the plunger or

displacement relay, is used in high

current, high voltage applications

that could include lighting,

resistance heating, or power

supply switching (M2P2).
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 267

Reduction Works!

Honeywell Corporation has been

running a free take-back program

in Minnesota to collect any brand

of used mercury-containing

thermostat through either a

reverse distribution system or a

recycle by-mail system.

Honeywell works with heating,

ventilating, and air-conditioning

(HVAC) wholesalers who sell

their products. Honeywell has one

license (called a network license)

for all the wholesalers who are

participating as a consolidation

point for the thermostats. HVAC

wholesalers contact their

Honeywell customer service

representatives to order containers

for used thermostats, and

Honeywell sends the wholesaler a

plastic container with an attached

lid that holds 100 thermostats.

Homeowners who replace their

own thermostats without

contractor assistance or with

contractors who are not currently

participating in the Honeywell

program may recycle their

thermostats through the free

recycle-by-mail system. These

individuals can call a toll-free

number to receive a free postage

paid thermostat mailer.

Switch Quantity of

Mercury

Available Alternatives

Tilt Switch

· Thermostats 3,000 - 6,000 mg Electronic type and snap switches

· Float Control

(septic tank and sump pumps)

? Magnetic dry reed switch, optic sensor, or

mechanical switch

· Freezer Light 2,000 mg Mechanical switch

· Washing Machine

(power shut off)

2,000 mg Mechanical switch

· Silent Switches

(light switches prior to 1991)

2,600 mg Mechanical switch

Thermo-Electrical Applications

· Accustat

(“mercury in glass thermostat,” a

calibrated device resembling a

thermometer is used to provide

precise temperature control for

specialized applications)

~ 1,000 mg ?

· Flame Sensor

(used in residential and commercial

gas ranges, mercury is in capillary

tube when heated mercury

vaporizes and opens gas valve or

operates switch. Used for both

electrical or mechanical output.)

2,500 mg Hot surface ignition system for devices or

products that have electrical connections.

Mercury Switches in Electrical Applications

Source: Michigan Mercury Pollution Prevention Task Force, 1996
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268 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

MERCURY SPILLS

As a dentist, you will probably continue to encounter mercury for some

time to come. Therefore, it is essential to handle mercury, especially

bulk mercury, safely. Small droplets of spilled mercury may lodge in

cracks and sinks, mix with dust, accumulate on work surfaces, and

adhere to knit fabrics, shoe soles, watches, gold, and other jewelry. This

allows for mercury to potentially be transported to other locations,

homes, or businesses.

The Costs of Mercury Spills

Mercury spills can be expensive for a number of reasons. Here are

some examples:

The Cost of Clean-up

◆ A mercury-containing sphygmomanometer broken on a carpeted

floor at Butterworth Hospital cost $2000 to clean up.

Labor costs

◆ It took Riverside Hospital 8 to 16 hours to clean up a mercury

spill (the mercury had fallen in tile crevices).

Facility Down-Time

◆ The room in which a mercury spill occurs will be unavailable for

use until the site is decontaminated. Riverside Hospital found

that their room was out of service for at least one day.

Equipment Loss

◆ A mercury-containing switch in an oven in a University of

Michigan Hospital cafeteria exploded. It cost $3500 to clean up

the spill. The oven, a $25,000 piece of equipment, was

irreparably damaged.

Training Time

◆ Continuing to use mercury containing items can be expensive for

your facility because of the needed staff training for spill

response plans. However, if you are still using mercurycontaining products, don’t neglect this important step! An

improperly handled spill can end up costing even more to

decontaminate.

Handle Mercury

Safely!

✔ Use mercury only in

uncarpeted, well-ventilated

areas. Provide troughs on

smooth surfaced tables and

benches to collect mercury

spills. Reserve the room for

mercury use only; restrict

traffic in the area.

 ✔ Ask workers to remove all

watches and other jewelry -

especially gold jewelry since

mercury readily combines with

gold - and have them wear a

mercury vapor respirator and

protective clothing: gloves,

disposable gowns, and shoe

coverings.

✔ Prohibit smoking, eating, and

drinking in the area.

✔ Train all workers to understand

the properties and hazards of

mercury and to carry out safe

handling procedures and

specific policies related to

mercury disposal.

 ✔ Clean and calibrate all mercurycontaining equipment

according to the manufacturer’s

recommended handling

procedures and the formal

procedures posed by your

communications or safety

program supervisors.

 ✔ Ask your safety supply vendor

for a mercury vacuum sweeper

and spill cleanup kit. Having

the right equipment on hand

will limit the amount of mercury

released into the atmosphere.

- From “The Case Against Mercury: Rx

for Pollution Prevention,” The Terrane

Institute
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 269

ACTION IDEAS FOR DENTISTS TO CONSIDER

✔ Eliminate the use of bulk mercury and bulk amalgam alloy in your practice; use precapsulated

amalgam alloy only

✔ Use a chair-side trap or other capture device to collect your waste amalgam. Educate staff on how to

effectively use the equipment .

✔ Recycle the waste amalgam you collect in your traps. Never throw it in the garbage or in the medical

waste red bags!

✔ Continue to educate yourself and your colleagues about amalgam alternatives

✔ Continue to use fluorescent lamps! Even though fluorescent lamps contain mercury, they are a good

choice because they use much less energy than regular bulbs.

✔ Establish a lamp recycling program for your business. Try not to break these lamps because some of

the mercury will escape into the air.

✔ When remodeling or replacing old equipment, replace thermostats containing mercury switches with

thermostats containing electronic type and snap switches, and replace “silent” light switches with

mechanical light switches.

✔ Clean or flush the traps, sumps, and pipes in your sewer lines to rid your facility of historical uses of

mercury. See excerpts from the MWRA/MASCO Infrastructure Subcommittee Maintenance

Guidebook that appear in the “Resources” section of this sourcebook for more information.
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270 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

SAMPLE PROCLAMATION

Your dental clinic may wish to formally declare your commitment to mercury reduction. You may use the

proclamation below, or adopt it to suit your needs.

WHEREAS mercury is an elemental substance, that once released into the environment, easily and rapidly

changes forms to several organic and inorganic states that transfer from soil to air to water and back again;

WHEREAS the organic form of mercury, methylmercury, bioaccumulates in aquatic ecosystems to magnify

concentrations in animal tissue in increasing degrees up to 250,000 times;

WHEREAS methylmercury, the most toxic form of mercury, can affect the reproductive efforts of top

predators in aquatic environments such as loons, otters, mink, and panthers;

WHEREAS the neurotoxic effects of high levels of methylmercury poisoning in humans has been established,

and low-level doses of methylmercury consumption can potentially effect human health, especially that of a

fetus;

WHEREAS elemental mercury is a highly toxic substance which can vaporize easily and cause both acute and

chronic health effects including severe respiratory irritation and damage to the central nervous system;

WHEREAS mercury has been identified internationally as a toxic substance of concern, and mercury

contamination has led to fish consumption advisories for more than 235 lakes and 350 miles of rivers in

Wisconsin;

WHEREAS the majority of mercury entering Wisconsin comes from anthropogenic sources, and one-quarter

of these emissions are the result of the purposeful use of mercury;

WHEREAS mercury is used widely in consumer and industrial products, where, in most cases, alternative,

mercury-free products are available;

WHEREAS pollution prevention or product substitution is a progressive approach to protecting the

environment that eliminates or minimizes the generation of mercury-bearing waste, making it one of the most

favorable strategies for maintaining a clean environment;

WHEREAS pollution prevention for mercury can help environmental conditions, as well as protect the health

and safety of workers;

WHEREAS recognizing mercury minimization as an active opportunity to improve the environment of

Wisconsin and the environment of our business, we, the undersigned, do hereby declare our business to be a

mercury minimization participant;
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 271

WE commit to research the following mercury minimization opportunities in our facility and implement those

we find most feasible:

◆ Continue education about amalgam alternatives

◆ Use a chair-side trap or other capture device to collect waste amalgam. Educate staff on how to use

effectively use the equipment .

◆ Recycle the waste amalgam collected in the traps.

◆ Eliminate the use of bulk mercury and bulk amalgam alloy; use precapsulated amalgam alloy only

◆ Recycle any bulk mercury still at facility

◆ Use safe, non-mercury cleaners and degreasers in labs, housekeeping departments, and maintenance

areas

◆ Replace mercury-containing thermostats and switches with mercury-free alternatives when

remodeling or replacing old equipment

◆ Recycle fluorescent lamps

◆ Establish effective spill response measures to ensure the mercury already in your facility is handled in

a safe and proper manner.

_________________________________________

Facility

_________________________________________ ________________________

Name Date Signed
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272 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

BIBLIOGRAPHY

The information included in the pamphlet is essentially a compilation of the best mercury pollution

prevention work to date. Information was gathered from the documents below; some material may have

been quoted directly from these sources:

“A Guide for Dentists: How to Manage Waste from Your Dental Practice,” Western Lake Superior Sanitary

District, 1993

“A Guide for Dentists: How to Manage Waste from Your Dental Practice,” University of Wisconsin-Extension

Solid and Hazardous Waste Education Center, 1996

“At the Source,” Great Lakes Pollution Prevention Centre, Fall 1995

“Best Management Practices for Hospitals and Medical Facilities,” Palo Alto Regional Water Quality Control

Plant, September 1994

“Business Waste Reduction and Recycling: A Guide For The Workplace,” Wisconsin DNR, 1995

“DNR Briefing Paper: How to Handle Your Waste Fluorescent Lamps and Incandescent Bulbs,” Wisconsin

DNR 1995

“Dental Amalgam-Environmental Aspects,” D. Arenholt-Binslev, Adv Dent Res 6:125-130, September, 1992

“Facts About Amalgam/Mercury,” Detroit Waster and Sewerage Department

“Hospital Mercury Work Group Operations Subcommittee Final Report,” Massachusetts Water Resources

Authority (MWRA) and MASCO Mercury Work Group, August 21, 1995

“Hospital Success Stories” (presentation), Jennifer Carver, University of Michigan Hospitals, presented at

“Mercury Pollution Prevention: Healthcare Providers Protecting People and the Great Lakes,” Novi, Michigan

October 4, 1996

“Household Fluorescent Lights: A Household Hazardous Waste Fact Sheet,” MPCA, August 1994

“How to Design and Administer a Hospital Mercury Reduction Plan” (presentation), David Smith, Riverside

Hospital, presented at “Mercury Pollution Prevention: Healthcare Providers Protecting People and the Great

Lakes,” Novi, Michigan October 4, 1996

“June Update, WLSSD Mercury Zero Discharge Project,” Western Lake Superior Sanitary District, June

1996

“MDA Initiatives on Mercury Pollution Prevention”

“Medical Waste Pollution Prevention: Keep Mercury Out of the Wastewater Stream,” USEPA Region 5,

September 1995
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 273

“Mercury Elimination and Reduction,” Pollution Probe, 1997

“Mercury in Minnesota Slide Show Script,” Western Lake Superior Sanitary District, November 1995

“Mercury Pollution Prevention Measures in Michigan Health Care Institutions,” Liz Krug and Guy Williams,

The National Wildlife Federation

“Mercury Products Study,” John Gilkeson, Minnesota Pollution Control Agency, May 1996

“Mercury Pollution Prevention in Michigan,” A Report by the Michigan Mercury Pollution Prevention Task

Force, April, 1996

“Mercury, Power Plants and the Environment: Basic Facts about Mercury and Coal-fired Power Plants, the

Environment, Fish and Wildlife, and Human Health,” compiled by Steven Ugoretz, WDNR

“Mercury in Medical Waste,” fact sheets 1-3, USEPA Region 5, September 1995

“Mercury Pollution Prevention in the Health Care System,” conference notes compiled by Emily Moore,

MPCA, April 1996

“Mercury in the Environment: The Waste Connection,” MPCA, MDEQ, WDNR

“Philips Unveils a Fluorescent Lamp With Less Mercury and a Long Life,” Wall Street Journal, June 9, 1995

“Preventing Mercury Waste Generation Through Comprehensive Environmental Management within the

Healthcare Industry,” Steering Committee Meeting Summary Notes, April 1996

“Sources of Mercury in Healthcare Business,” Detroit Water and Sewerage Department, July 1995

“Summary of the June 13, 1995 Meeting,” Detroit Waster and Sewerage Department Task Force for Mercury

Minimization from Dental Facilities

“Supplement to Annual Reports and Resolutions,” American Dental Association Board of Trustees, 1994

“Strategies for Mercury Control in Minnesota,” MPCA Mercury Task Force, July 1994

“The Case Against Mercury: Rx for Pollution Prevention,” The Terrane Institute

“The Concern Over Mercury and Wastewater,” Journal of the Michigan Dental Association, John Hughes and

Beverly J. Ingram, April/May 1995

“The Hunt for Quicksilver,” presented at AERB’s Wastewater Discharge Compliance Conference, November

17, 1992 by Frank Altmayer, Scientific Control Labs, Inc.

“The Use and Disposal of Amalgam (Mercury) In The Dental Office,” HHR Update, Michigan Dental

Association, Connie M. Verhagen, D.D.S., M.S., June 1995
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274 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

“Waste Management and Recycling for the Michigan Dental Office,” HHR Update, Michigan Dental

Association, March 1996

“Wisconsin Recycling Markets Directory,” Wisconsin DNR, May 1995
Current Mercury Work – Dentists

Specific Outreach/Research

Project: Lake Superior Pollution Prevention Pilot

Description: A focus area of dentist and hospital outreach and product education/collection was

targeted for 1996 projects

Agencies working on this project:

WDNR

Project: MercAlert

Description: Mercury education and waste reduction program, focusing on dentists and the general

public

Agencies working on this project:

WLSSD

Project: Targeted Initiative: Dentists

Description: Outreach effort and study of recycling/disposal procedures; best management practice

document

Agencies working on this project:

WLSSD

Project: Lake Superior Implementation Plan Team

Description: A focus area of dentist and hospital outreach was targeted for 1996 projects

Agencies working on this project:

MPCA/OEA

WDNR

Project: Study of Dentist Mercury Use and Alternatives

Description: A section of the M2P

2

 Task Force examined sources and alternatives for mercury use

in dental settings. Includes a table of amalgam alternatives, collection of bulk mercury

from dentist offices, and research

Agencies working on this project:

MDEQ

Project: Mercury Minimization from Dental Facilities

Description: As part of Detroit’s Mercury Minimization Program, DWSD is establishing collaborative

voluntary efforts with the ADA, the MDA, and the Detroit District Dental Society. Task

Force of 20 members. Bulk mercury collection.

Agencies working on this project:

Detroit Water and Sewerage Department
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276 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

MERCURY AMALGAM LITERATURE

1. Adamkus, Valdus V., Great Lakes National Program Manager - EPA, Memorandum: Sale of Mercury by the

Federal Government, August 2, 1994.

2. American Dental Association, Dental Office Wastewater Position Paper, October, 1994.

3. Arenholt-Bindsley, D., Dental Amalgam - Environmental Aspects, September, 1992.

4. California Water Pollution Control Association, City and County of San Francisco, Dental Related Facilities -

Heavy Metals Loadings, The Bulletin, Fall, 1993.

5. Citizens for a Better Environment, LA Gear - Putting Profits Over People.

6. City of Detroit Water and Sewerage Department, Waste Reduction Sewers, August, 1984.

7. City and County of San Francisco Department of Public Works, Bureau of Environmental Regulation and

Management, Water Pollution Prevention Program, Dental Related Metals Inventory, January, 1993.

8. Clinical Research Associates Newsletter, Silver Amalgam & Its Alternatives - 1991, Volume 15, Issue 2 - February,

1991.

9. Darlin, Damon, Mercurial Sales, Forbes, Page 12, June 20, 1994.

10. Expert Panel on Mercury Atmospheric Processes, Mercury Atmospheric Processes: A Synthesis Report,

September, 1994.

11. FDI World, The Amalgam Story Continues, Page 13-16, July/August, 1994.

12. Fan, P.L. Chang, S.B., Siew. C., Environmental Hazard Evaluation of Amalgam Scrap, Dental Materials, November,

1992.

13. Flanders, Raymond A., D.D.S., MPH, Mercury in Dental Amalgam - A Public Health Concern?, Public Health

Dent, Page 303-311 Fall, 1992

14. Gaines, Dr., Amalgam Waste Water Research Needed, ADS Says, ADA News, October 17, 1994.

15. Huggins, Hal A. D.D.S., Mercury & Other Toxic Metals in Humans: Proceedings of the First International

Conference on Biocompatibility of Materials.

16. Journal of Environmental Health, New Dental Amalgam Will Eliminate Mercury Content, December, 1993.

17. Kodak Dentel Radiography Series, Waste Management Guidelines, June 1994.

18. Lake Superior Partnership-Western Lake Superior Sanitary District, Dental Mercury Pollution Prevention Program.

19. Lawrence, David F., Memo - Dental Amalgam Survey Update, September 6, 1994.

20. Leinfelder, Karl F., D.D.S., M.S., After Amalgam, What Other Materials Fall Short?, JADA, May 1994.

21. Mason, R.P., Pitzgerald, W.F. and Morel, F.M.M., The Biogeochemical Cycling of Elemental Mercury:

Anthropogenic Influences.

22. Mercury and the Environment, Natural Sources.

23. METASYS; 1994, Amalgam Seperation - What You Should Know; Superior System; Amalgam Separator -

Multi System Type 1, Floor Model Description and Technical Data; Green & Clean M2 - The Dual Hygiene

System.
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 277

24. METRO; King County Department of Metropolitan Services, Draft Regulation of the Discharge of Amalgam

Waste Products from Dental Offices, October, 1994.

25. METRO, Municipality of Metropolitan Seattle, Dental office Waste Stream Characterization Study, September,

1991.

26. Michigan Department of Natural Resources, Implementaiton of MESB Mercury Report Recumn, November,

1993.

27. Michigan Department of Natural Resources, Lake Superior Pollution Prevention Strategy, October, 1993.

28. Michigan Department of Natural Resources, Mercury in Michigan’s Environment: Causes and Extent of the

Problem and Strategy for Abatement, March 12, 1992.

29. Michigan Environmental Science Board, Mercury in Michigan’s Environment: Environmental and Human

Health Concerns, (A Science Report to Governor John Engler), April, 1993.

30. Minnesota Pollution Control Agency Mercury Task Force, Strategies for Mercury Control in Minnesota, 1994.

31. Municipality of Metropolitan Seattle, METRO, Waste Management guidelines for Kine County Dental Offices.

Published by METRO as a Service of the Local Hazardous Waste Management Program, July, 1993.

32. National Wildlife Federation, Great Lakes Natural Resources Center; Prospectus for Prevention & Minimizing

Mercury Loadings to the Detroit Water & Sewerage [District Treatment Plant], August, 1994.

33. Poulson, David, U.S. Defense Department Halts Mercury Sales, Booth Newshouse Newspapers, July 7, 1994.

34. Radian Corporation, Mercury Control Technologies and Coast Report Prepared for Office of Air Quality

Planning and Standards, September 30, 1993.

35. Research Triangle Institute, Mercury Control Technologies and Costing of Activated Carbon injection for the

Electric Utility Industry, Prepared for Emissions Standards Division.

36. Rochester Series on Environmental Toxicity, Advances in Mercury Toxicology.

37. Rogers, Kenneth D., M.D., Status of Scrap (Recyclable) Dental Amalgams ad Environmental Health Hazards

or Toxic Substances, JADA, July, 1989.

38. Ross and Associates, Mercury Sources and Regulations, Background Information for the Virtual Elimination

Pilot Project, Prepared for U.S. EPA Gret Lakes National Program Office, September 12, 1994.

39. Rourke, Daniel, City and County of San Francisco - Dental Related Facilities, Heavy Metals Loadings, California

Water Pollution Control Association Bulletin, Page 10, 12 and 14, Fall, 1993.

40. Rowe, Nathaniel H., D.D.S., M.H.D., & Chadzynski, R.S., M.P.H., A Study of the Waste Management of One

Regulated Infectius Medical Waste: Shartp Disposal, October, 1993.

41. Sills, Robert, Great Lakes and Environmental Assessment Section Surface Water Quality Division, Mercury in

Michigan’s Environment (Causes and Extent of the Problem, June 24, 1992.

42. Sources of Human and Environmental Exposure.

43. Suzuki, Tsuguyoshi; Imura, Nobumasa; Clarkson, Thomas W., Rochester Serioes on Environmental Toxicity,

Advances in Mercury Toxicology, 1991.

44. Swedish Environmental Protection Agency, Waste Management in Sweden for Mercury Containing Waste

Products, 1994.
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278 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

45. Taylor, Joyal, D.D.S., The Complete Guide to Mercury Toxicity from Dental Fillings - How to Find Out If

Your Silver Dental Fillings Are Poisoning You and What You Can Do About It, 1988.

46. United States Department of Interior, Bureau of Mines, Mercury in 1992, July, 1993.

47. United States Department of Interior, Bureau of Mines, Mineral Industry Surveys, July 27, 1993.

48. Unites States Environmental Protection Agency, Guides to Pollution Prevention - Selected Hospital Waste

Streams, June, 1990.

49. United States Environmental Protection Agency, The EPA Great Waters Program: An Introduction to the

Issues and the Ecosystems, April, 1994.

50. Washington State Dental Association, WSDA News, May, 1994.

51. Welland, Cynthia (Metro Chemist), Dental Office Waste Stream Characterization Study, September, 1991/

Reprinted November, 1993.

52. The Western lake Superior Sanitary District, A Guide for Dentist - How to Manage Waste From Your Dental

Practice, March 1993.

53. The Wester Lake Superior, Sanitary District, Mercury, July, 1994.

54. World Health Organization, International Programme on Chemical Safety.

55. Yuen, Stephen, Dr., California Requires Use of Universal Precautions, ADA News, October 17, 1994.

56. Zapp, John S., D.D.S., Executive Director, American Dental Association, Memo: ADA Assistance with Dental

Office Waste Issues, June 6, 1994.
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 279

MORE ARTICLES ABOUT MERCURY-AMALGAM

FILLINGS

The following is a list of abstracts of articles about the mercury- amalgam health-field. Please note that

this is a very subjective selection by Leif Hedegard. Updated 8 April 1996.

give web address

Ahlqwist M, Bengtsson C, Lapidus L, Lindstedt G & Lissner L. Concentrations of blood, serum and urine

components in relation to number of amalgam tooth fillings in Swedish women. Comm Dent Oral Epidem

23(4):217-221 (1995)

ABSTRACT: “ Altogether 1462 women aged 38, 46, 50, 54 and 60 yr were examined in 1968/69 in a

combined medical and dental population study in Gothenburg, Sweden. Number of tooth surfaces restored with

amalgam fillings was assessed. The examination was repeated in 1980/81 including a new dental examination.

The results from a number of biochemical analyses of blood, serum and urine were analyzed for a possible

statistical relationship to number of dental amalgam fillings. As emphasis has been put in the literature on

special influence from amalgam on kidney function and on the immunological system, special attention was

paid to variables which might reflect these functions in our analyses. When potential confounders were taken

into consideration, no significant correlations remained which seemed to be of clinical importance. Specifically,

amalgam fillings were not found to be associated with impairment of the kidney function or the immunological

status.”

Bjorkman L, Pedersen N & Lichtenstein P. Physical and mental health related to dental amalgam fillings in

Swedish twins. Submitted for publication 1995. This article can be found in: Bjorkman L. Studies on Dental

Amalgam and Mercury. Exposure, Accumulation and Effects. Thesis, Institute of Environmental Medicine.

Karolinska Institutet, Stockholm Sweden 1995 (ISBN 91-628-1507-5)

ABSTRACT: “In the past years increasing attention has been paid to possible adverse health effects

associated to mercury exposure from dental amalgam fillings. To evaluate possible health effects from

amalgam fillings, dental status, registered by specially trained nurses, was obtained from 587 male and female

twins included in the ongoing Swedish Adoption/Twin Study of Aging (SATSA). Data on physical and mental

health were collected and memory function tested. Mean age was 66 years (SD 9, range 46-89). In the entire

material, 25 % of the individuals had no own teeth and in the group with own teeth the median number of teeth

surfaces filled with dental amalgam was 15 (range 0-65). Analyses of associations between dental amalgam

and a number of scales estimating somatic and mental health and memory functions were performed both

using the entire group and after excluding individuals with less than 12 teeth. Regardless of the sample no

negative effects on physical or mental health were found from amount of dental amalgam. On the contrary, a

positive correlation between performance in the memory tests and number of teeth surfaces filled with dental

amalgam was found. After controlling for age, gender, education and number of remaining teeth this

association generally disappeared. When using a co-twin control design with twin pairs discordant for amalgam

exposure, no negative health effects associated with dental amalgam were detected. This study does not

indicate any negative effects from dental amalgam on physical or mental health or memory functions in the

general population over 50 years of age.”
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280 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Borjesson J, Barregard L, Sallsten G, Schutz A, Jonson R, Alpsten M & Mattsson S. In vivo XRF analysis of

mercury: the relation between concentrations in the kidney and the urine. Phys Med Biol (P6J) 40(3):413-426

(1995)

ABSTRACT: “The objective of this study was to determine the concentrations of mercury in organs of

occupationally exposed workers using in vivo x-ray fluorescence analysis. Twenty mercury exposed workers

and twelve occupationally unexposed referents participated in the study. Their mercury levels in kidney, liver

and thyroid were measured using a technique based on excitation with partly plane polarized photons. The

mercury levels in blood and urine were determined using atomic absorption spectrophotometry. The detection

limit for mercury in the kidney was exceeded in nine of the exposed workers, but in none of the referents. The

mean kidney mercury concentration (including estimates below the detection limits) was 24 micrograms g-1 in

the exposed workers, and 1 microgram g-1 in the referents. The association between mercury in the kidney

and in urine was statistically significant, but it was unclear whether the relation was linear. The measurements

on liver (n = 10) and thyroid (n = 8) in the exposed workers showed mercury levels below the detection limit.

The study shows that it is now possible to measure the mercury concentrations in kidneys of occupationally

exposed persons, using in vivo x-ray fluorescence. The estimated concentrations are in reasonable agreement

with the limited human autopsy data, and the results of animal studies.”

Cavalleri A, Belotti L, Gobba FM, Luzzana G, Rosa P & Seghizzi P. Colour vision loss in workers exposed to

elemental mercury vapour. Toxicology Letters 77(1-3):351-356 (1995)

ABSTRACT: “We evaluated colour vision in 33 workers exposed to elemental mercury (Hg) vapour and in

33 referents matched for sex age, alcohol consumption and cigarette smoking. The results were expressed as

colour confusion index (CCI). In the workers urinary excretion of Hg (HgU) ranged from 28 to 287 ug/g

creatinine. Subclinical colour vision loss, mainly in the blue-yellow range, was observed in the workers. This

effect was related to exposure, as indicated by the correlation between HgU and CCI (r=0.488, P<0.001). In

the workers whose HgU exceeded 50 ug/g creatinine, mean CCI was significantly increased compared to the

matched referents. The results suggest that exposure to elemental Hg inducing HgU values exceeding 50 ug/g

creatinine can induce a dose-related colour vision loss.”

Echeverria D, Heyer NJ, Martin MD, Naleway CA, Woods JS & Bittner AC jr. Behavioral Effects of LowLevel Exposure to Hg0 Among Dentists. Neurotoxicol Teratol 17(2):161-168 (1995)

ABSTRACT: “Exposure thresholds for health effects associated with elemental mercury (Hg0) exposure

were examined by comparing behavioral test scores of 19 exposed (mean urinary Hg = 36 micrograms/l) with

those of 20 unexposed dentists. Thirty-six micrograms Hg/l is 7 times greater than the 5 micrograms Hg/l

mean level measured in a national sample of dentists. To improve the distinction between recent and

cumulative effects, the study also evaluated porphyrin concentrations in urine, which are correlated with renal

Hg content (a measure of cumulative body burden). Subjects provided an on-site spot urine sample, were

administered a l-h assessment consisting of a consent form, the Profile of Mood Scales, a symptom and

medical questionnaire, and 6 behavioral tests: digit-span, symbol-digit substituion, simple reaction time, the

ability to switch between tasks, vocabulary, and the One Hole Test. Multivariate regression techniques were

used to evaluate dose-effects controlling for the effects of age, race, gender and alcohol consumption. A doseeffect was considered statistically significant below a p value of 0.05. Significant urinary Hg dose-effects

were found for poor mental concentration, emotional lability, somatosensory irritation, and mood scores.

Individual tests evaluating cognitive and motor function changed in the expected directions but were not

significantly associated with urinary Hg. However, the pooled sum of rank scores for combinations of tests

within domains were significantly associated with urinary Hg, providing evidence of subtle preclinical changes

in behavior associated with Hg exposure. Coproporphyrin, one of three urinary porphyrins altered by mercury

exposure, was significantly associated with deficits in digit span and simple reaction time. The prophyrin pooled

sums of rank scores were as sensitive as the urinary Hg analyses within the cognitive and motor domains but
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 281

were less sensitive for the overall battery of tests. The reported effects were detected among dentists with a

mean urinary Hg level of 36 micrograms/l, which lies between the proposed biologic thresholds of 25 and 50

micrograms Hg/creatinine, suggesting the need for a more comprehensive study to determine the threshold of

adverse biologic effects.”

Ellingsen DG, Nordhagen HP & Thomassen Y. Urinary Selenium Excretion in Workers with Low Exposure to

Mercury Vapour. J Appl Toxicol 15(1):33-36 (1995)

ABSTRACT: “Urinary selenium excretion was studied in 21 mercury vapour (Hg0)-exposed workers

involved in the demolition of a chloralkali plant. The subjects had no known previous occupational exposure to

mercury. Their mean pre-exposure urinary mercury concentration, determined on average 1.2 days prior to the

exposure, was 0.8 nmol/mmol creatinine (range 0.3-1.9). Their last mean urinary mercury concentration,

determined on average after 51.4 days (range 19-103) of exposure, was 4.8 nmol/mmol creatinine (range 1.2-

10.0). The exposure ceased on average 4.1 days after the last determined urinary mercury concentration. The

corresponding concentrations of urinary selenium decreased from an average of 39.1 nmol/mmol creatinine

(range 13.9-89.5) to 29.0 nmol/mmol creatinine (range 10.1-52.9) (P=0.002). This finding may indicate that

even a low to moderate work-related exposure to Hg0 may reduce the urinary selenium concentration in

humans in a manner that is not yet fully known”

Enestrom S & Hultman P. Does Amalgam Affect the Immune System? A Controversial Issue. Int Arch

Allergy Immunol 106:180-203 (1995)

ABSTRACT: “Although in use for more than 150 years, dental amalgam has been questioned more or less

vigorously as a dental restoration material due to its alleged health hazards. Humans are exposed to mercury

and the other main dental amalgam metals (Ag, Sn, Cu, Zn) via vapour, corrosion products in swallowed saliva,

and direct absorption into the blood from the oral cavity. Dental amalgam fillings are the most important source

of mercury exposure in the general population. Local, and in some instances, systemic hypersensitivity

reactions to dental amalgam metals, especially mercury, occur at a low frequency among amalgam bearers.

Experimental and clinical data strongly indicate that these and other subclinical systemic adverse

immunological reactions to dental amalgam metals in humans will be linked to certain MHC genotypes, and

affect only a small number of the exposed individuals. These individuals will be very difficult to detect in a

mixed population of suspectible and resistant individuals, including persons with alleged symptoms due to dental

amalgam fillings, where many of the individuals are likely to suffer from conditions with no proven

immunological background such as multiple chemical sensitivity syndrome. Intensified studies should be

performed to identify such susceptible MHC genotypes, taking advantage of the reported cases of more

heavily metal-exposed humans with systemic autoimmune reactions. Further studies will also be needed to

ascertain whether the combined exposure to the metals in dental amalgam may lower the threshold for

adverse immunological reactions, since recent studies have shown that the metals in alloy, especially silver,

may induce autoimmunity in genetically susceptible mice.”

End of abstract. A quote follows:

“... Very recent results (Hultman et al., in prep) in genetically suspectible rats implanted with

conventional dental amalgam fillings in 4 teeth revealed a stimulation of B cells, measured as a

significant increase in serum IgE, followed by systemic immune complex deposits...”

Eti S, Weisman R, Hoffman R & Reidenberg. Slight Renal Effect of Mercury from Amalgam Fillings. Pharm

& Toxicol 76:47-49 (1995)

ABSTRACT: “The current study was to answer the question: Is enough mercury absorbed from dental

amalgam fillings to produce renal damage? One hundered healthy adults (18-44 years old) filled out health

questionnaries and voided urine samples. Urine mercury concentration and N-acetyl-beta-glukosaminidase
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282 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

(NAG) were measured. Subjects were grouped into those having amalgam fillings (N=66) and those without

(N=34). Median 95% Confidence Interval) urine mercury was 1 (1-2) and 0 (0-0.6) ng/ml (P<0.01) and

median urine NAG was 23 (18-27) and 16 (11-18) units (P<0.05) in the two groups respectively. People with

mercury amalgam fillings excreted slightly more mercury than people without them, and have a very small

increase in urinary NAG excretion that is probably of no clinical significance. This dose of mercury absorbed

from amalgam appears to be too little to be a health hazard for renal injury.”

Fuortes LJ, Weismann DN, Graeff ML, Bale JF, Tannous R & Peters C. Immune trombocytopenia and

elemental mercury poisoning. J Toxicol - Clin Toxicol 33(5):449-455 (1995)

ABSTRACT: “ Three cases of severe mercury toxicity occurring within a family are reported. Two cases of

thrombocytopenia occurred in this family and represent the second such report in the literature of an

association between elemental mercury toxicity and thrombocytopenia. Three of the children presented with a

combination of dermatologic and neurologic manifestations reminiscent of acrodynia or pink disease. Each of

the four children in this family were treated with dimercaptosuccinic acid. The hazard of vacuuming spilled

mercury and appropriate clean-up procedures are described.”

Gonzalez-Ramirez D, Maiorino RM, Zuniga-Charles M, Xu Z, Hurlbut KM, Junco-Munoz P, Aposhian MM;

Dart RC, Diaz Gama JH, Echeverria D et al. Sodium 2,3-dimercaptopropane-1-sulfonate challange test for

mercury in humans: II. Urinary mercury, porphyrins and neurobehavioral changes of dental workers in

Monterrey, Mexico. J Pharmacol Exp Ther 272(1):264-274 (1995)

ABSTRACT: “The sodium salt of 2,3-dimercaptopropane-1-sulfonic acid (DMPS) challange test (300 mg

p.o. after an 11-hr fast) was given in Monterrey, Mexico to dental and non-dental personnel. Urine samples

were collected and analyzed for total mercury. The mean mercury urinary excretion (+/- S.E.) for 6 hr before

and 6 hr after DMPS administration for 10 dental technicians, who formulate amalgam, was 4.84 micrograms

+/- 0.742 and 424.0 micrograms +/- 84.9; for 5 dentists, who use amalgam in their practice, 3.28 micrograms

+/- 1.11 and 162.0 micrograms +/- 51.2; and for 13 nondental personnel, 0.783 microgram +/- 0.189 and 27.3

micrograms +/- 3.19. The urinary coproporphyrin levels before DMPS administration, which are indicative of

renal mercury content, were quantitatively associated with the urinary mercury levels among the three study

groups after DMPS administration. This was not so if the urinary mercury level before DMPS administration

was compared with the urinary coproporphyrin concentration. The urinary mercury level after DMPS

administration is a better indicator of exposure and renal mercury burden than is the mercury level measured in

the urine before DMPS is given. Regression analysis showed that the coefficient of urinary mercury was

statistically and adversily associated with complex attention (switching task), the perceptual motor task

(symbol-digit substitution), symptoms and mood. The easily performed DMPS-mercury challenge test is useful

for monitoring dental personnel for mercury vapor exposure.”

Gothe CJ, Odont CM & Nilsson CG. The environmental somatization syndrome. Psychosomatics 36(1):1-11

(1995)

ABSTRACT: “Patients with environmental somatization syndrome (ESS) believe that their symptoms are

caused by exposure to tangible components of the external environment or by ergonomic stress at work. ESS

is distinguishable by mental contagiousness and by the patients’ focus on the external environment as cause of

the illness. The presentation is often polysymptomatic, and epidemic outbreaks may appear. The patients

usually refuse alternative explanations of their symptoms and discredit and reject any suggestion of a

psychogenic etiology. It is important to distinguish between hygienic problems and ESS problems, particularly

when poor and inadequate hygienic factors are present simultaneously with an ESS epidemic.”
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 283

Grandjean P. Individual susceptibility in occupational and environmental toxicology. Toxicol Lett 77(1-3):105-108

(1995)

ABSTRACT: “By prudent interpretation of toxicological and epidemiological evidence, susceptibility could

become a very useful notion, both in a scientific sense and for prevention of adverse effects. Based on

presumed aetiology, susceptibility can often be separated into genetic, constitutional, and environmental

categories, although some overlapping between these groups will be apparent. Inherited factors seem to be

involved in determining many toxic effects of environmental chemicals, including carcinogenic responses,

although some of the evidence is equivocal. Among constitutional factors, sex, age and pregnancy are major

determinants of individual susceptibility. An individual’s resistance toward chemical toxicity may also be

affected by other environmental exposures, including those associated with diet and lifestyle. The mechanisms

involved are only partially known but are likely to include both toxicokinetic and toxicodynamic interactions.

Three major types can be recognised: (1) factors that increase the concentration of the biologically active

substance at the active site; (2) factors that augment the reaction of the chemical substance with target

molecules in the body, thereby initiating the response; and (3) factors that promote the sequence of events

between the initial reaction and the final manifestation of an adverse health effect. Specifically, a decrease in

the body’s reserve capacity may not be readily observable and may only reveal itself as a weakening of the

defence mechanisms. The causes of hypersusceptibility and its effects on toxic responses are little known and

deserve to be explored systematically.”

Guerrier P, Weber J-P, Cote R, Paul M & Rhainds M. The accelerated reduction and elimination of toxics in

Canada: the case of mercury-containing medical instruments in Quebec hospital centres. Water, air, and soil

pollution 80:1199-1202 (1995)

ABSTRACT: “In Canada, medical instruments containing mercury (Hg) are still widely used in hospitals.

These are mostly thermometers and sphygmomanometers. Mercury present in these instruments does not

itself consitute a risk of contamination since the metal is contained within a closed system. however, breakage,

inadequate maintenance and disposal of such instruments can expose workers and the public to this toxic

substance. In Quebec 80% of the 28 hospitals surveyed still use Hg sphygmomanometers and 45% Hg

thermometers. Besides, 35% do not have any recovery procedures in case of spillage and most mercury spills

are apparently not reported. Two main courses of action are recommended: the gradual replacement of these

medicla instruments by aneroid sphygmomanometers and electronic thermometers, and the establishment and

communication, in form of a handbook, of guidelines to handle and dispose of mercury safely.”

Gustafsson E. Swedish experiences of the ban on products containing mercury. Water, Air, and Soil Pollution

80:99-102 (1995)

ABSTRACT: “The Swedish Parliament has decided that the use of mercury (Hg) must cease. Risk reuction

measures are to be carried out with and without the support of legislation. According to decisions taken in May

1994 the aim is, with a few exemptions, to end the use of Hg in processes and products by the year 2000.

Special attention has been paid to products containing Hg. Most uses of Hg-containing measuring instruments

and electrical components have successively been phased out in Sweden. It can be concluded that most such

uses have reliable Hg-free alternatives.”

Liang L I & Brooks RJ. Mercury reactions in the human mouth with dental amalgams. Water, Air, and Soil

Pollution 80:103-107 (1995)

ABSTRACT: “This is a preliminary study of the reactions of mercury (Hg) in the human mouth with dental

amalgams. It was conducted by analysing saliva samples from subjects with amalgam fillings and control

subjects with no amalgams. Samples were collected both prior to and after cleaning the mouth. These samples

were analyzed for elemental mercury (Hg0), inorganic mercury (Hg2+) and methylmercury (MeHg). We

concluded that the concemntrations after cleaning represented the systemic concentrations. Hg2+ and MeHg
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284 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

were found in all systemic samples from both subjects and controls, while Hg0 was found only in the samples

from subjects with amalgams. In the control group, the concentrations found before and after cleaning the

mouth were equivalent. In the amalgam group, concentrations of Hg2+ found before cleaning the mouth were

10 to 40 times higher than those found after cleaning, suggesting that the oxidation reaction of Hg0 into Hg2+

takes place. For MeHg, a similar but less pronounced pattern as Hg2+ was found, supporting methylation in

the mouth.”

Louwerse ES, Buchet J-P, Van Dijk MA, de Jong VJMB & Lauwerys RR. Urinary excretion of lead and

mercury after oral administration of meso-2,3-dimercaptosuccinic acid in patients with motor neurone disease.

Int Arch Occup Environ Health 67:135-138 (1995)

ABSTRACT: “Amyotrophic lateral slerosis (ALS) and spinal muscular atrophy (SMA) are progressive

neurodegenerative disorders involving motor neurons. The aetiology of the non-familiar forms is still unknown

but it has been suggested that long-term exposure may play a role in the pathogenesis of these diseases. In 53

patients suffering from ALS (n=42) and SMA (n=9) the oral administration of dimercaptosuccinic acid

(DMSA, 20 mg/kg) did not result in a greater mobilization of lead and mercury from peripheral depots than in

control subjects. Although it can not be excluded that the amount of lead or mercury excreted after DMSA

administration may not be a reflection of the amount accumulated in the motor neurones, this study does not

provide support for the hypothesis that heavy metals play a significant role in the occurrence of motor neurone

diseases.”

Maretta M, Marettov:a E, Skrob:anek P & Lede:c M. Effect of mercury on the seminiferous epithelium of the

fowl testis. Acta Vet Hung 43(1):153-61 (1995)

ABSTRACT: “ Phenylmercuric chloride was applied in three doses (5 ppm, 30 ppm Hg, and 30 ppm Hg + 4

ppm Se) via the food for 60 days. The effect of Hg with an without Se was studied histologically and the data

of a shortened spermatogram were evaluated. Treatment with 30 ppm Hg resulted in hypospermia, occurrence

of abnormally maturing spermatozoa, reduction of the volume of semen, and decrease in the number of

spermatozoa. The dose of 5 ppm Hg only resulted in the appearance of abnormally developing cells and

decreased sperm motility. The addition of Se maintained spermatogenesis and the values of semen on the

control level.”

McCann. Intravenous gamma globulin (IVIG) treatment of autoimmune kidney disease associated with

mercury ( Hg++) toxicity. J Allergy Clin Immunol 95(1)(Pt 2):145 Abstract 18 (1995)

ABSTRACT: “Tiny amounts of Hg++ (10(-6)) regulary induce in Brown-Norway rats, but not in outbred

strains, autoimmune renal disease characterized by polyclonal activation of B-cells, hypergammaglobulinemia

with antibodies against a variety of antigens as well as autoreactive T cells directed against Class II molecules.

The same could occur in humans but only in those who are genetically susceptible. RS, a 31 yr old Finn,

developed fatigue and recurrent infections (aseptic meningitis, pneumonia, sinusitis, pseudomonas

pyelonephritis) beginning at age 9. He was heavily exposed to Hg++. Urine Hg = >800 ug/L. His illness

exaberated following simultaneous removal of 21 large Hg-amalgam fillings along with chelation therapy

(EDTA & DMPS). Over the next yr he had 70 lb wgt loss, gastroenteritis, monilial stomatitis, granulocytopenia

and proteinuria. IgG=14.6 gm/L, CD8 lymphocytes= 50% CD4/CD8=0.9, CD8 HLADR=20u/L(N=>149).

Antimyelin IgM antibody was pos. The only successful treatment was IVIG, 400 mg/kg/mo. Creatinine Cl, 60

ml/min increased to > 80 ml/min, proteinuria cleared and weight gain resumed. His illness resembled AIDS but

repeated HIV testing was neg. This case suggests that traditional toxicological thinking in which symptoms

should be dose related to total body Hg++ burden in all individuals in a group, needs to be changed to recognize

genetic variability.”
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 285

Molin M, Berglund JR & Mackert Jr. Kinetics of mercury in blood and urine after amalgam removal. J Dent

Res 74:420 IADR Abstract 159 (1995)

ABSTRACT: “Even though a number of studies have not been able to reveal any correlation between

subjective symptoms and amalgam load there still are speculations wether patients with subjective symptoms

related by the patients themselves to their amalgam fillings could have a changed pattern of elimination of

mercury. The aim of the present investigation was to study the elimination half-time of mercury in plasma.

erythrocytes and urine over an extended period of time after amalgam removal in a group of 10 patients with

subjective symptoms by the patients themselves reffered to their amalgam fillings and a group of 8 healthy

subjects. The average number of occlusal and total amalgam surfaces in the patient group were 13.0 (range 4

- 20) and 44.4 (range 24 - 68), respectively. Corresponding figures in the control group were 12.9 (range 10 -

16) and 40.9 (range 24 - 63). The amalgam removal using rubberdam, water spray cutting and high volume

vacuum evacuator, was carried out at one and the same time. Blood and urine samples were collected at two

occasions before the amalgam removal, then blood was collected at thirthytwo occasions and urine at

forthythree occasions during the following year. The mercury content wasanalysed by CVAAS technique. The

measured P-, Ery- and U-Hg concentrations before amalgam removal were slightly higher in the control group

6.4+/-3.3 nmol/L, 19.4+/-6.6 nmol/L, and 2.7+/-1.3 nmol/mmol creatinine respectively than in the symptom

group 5.6+/-1.8 nmol/L, 14.8+/-8.8 nmol/L, and 1.6+/-0.9 nmol/mmol creatinine respectively. The Hgconcentrations did not significantly increase in the two groups after amalgam removal. Six days after the

removal the plasma mean concentrationwas significantly decreased at p<0.05 level and ten days after the

decrease was at a permanent p<0.005 level. The mean Ery-Hg level was significantly decreased after eleven

days (p<0.05) a level that remainedstabel for the rest of the year. The mean U-Hg level was significantly

decreased one month after the removal and after six months the mean level was reduced with 80% compared

to the initial level in bothgroups. The conclusion to be drawn from the present study is that the symptom group

did not have a changed pattern of elimination of mercury compared to the healthy group.”

Moszczy:nski P, S:owi:nski S, Rutkowski J, Bem S & Jakus-Stoga D. Lymphocytes, T and NK cells, in men

occupationally exposed to mercury vapours. Int J Occup Med Environ Health 8(1):49-56 (1995)

ABSTRACT: “ Lymphocytes, T-cells (CD3+), T-helper (CD4+) and T-suppressor (CD8+) as well as NKcells (CD16+) counts were determined in the peripheral blood of 81 males occupationally exposed to metallic

mercury vapours and of 36 non-exposed males using monoclonal antibodies in indirect immunofluorescence

tests. Mean weighted mercury concentration in air accounted for 0.0028 mg x m-3. Urine mercury

concentrations ranged from 0 to 240 micrograms x 1(-1) and concentrations in the blood varied from 0 to 30

micrograms x 1(-1). Stimulation of T-lymphocytes manifested by an increased number of T-cells, T-helper and

T-suppressor was observed. Quantitative change in T-cells night be an immunological index of exposure to

mercury vapours as indicated by a positive correlation between the exposure duration and the number of these

cells.”

Nakagawa R. Concentration of mercury in hair of diseased people in Japan. Chemosphere 30(1):135-140

(1995)

ABSTRACT: “The purpose of this investigation was to estimate the total hair mercury of diseased people

(not including patients of mercury poisoning such as Minamata disease). Hair samples were collected from

133 diseased volunteers in Tokyo and the surrounding areas from Oct. 1992 to June 1993. The total mercury

concentrations in the hair of ordinary diseased people (atopic dermatitis, asthma, dementia, cerebral infarct,

osteoporosis, hypertension and diabetes) were from 2.08 ppm to 36.5 ppm. Those values were considerably

higher than that of healthy people of the same age groups. However, the uptake routes and the metabolic

mechanism of high hair mercury concentrations in diseased people are not clear.”
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286 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Nuyts GD, Vanvlem E, Thys J, Deleersnijder D, Dhaese PC, Elseviers MM & Debroe ME. New

Occupational Risk Factors for Chronic Renal Failure. Lancet 346(8966):7-11 (1995)

ABSTRACT: “Occupational pollutants may have a role in development of chronic renal failure (CRF). Most

epidemiological studies have been cross-sectional, limited to certain renal diagnoses, or concentrated on early

transient renal effects. In a case-control study, we examined the association between CRF and occupational

exposure. Occupational histories of 272 men and women with CRF (of all types) were compared with those of

272 controls matched for age, sex, and region of residence. Exposures were assessed and degree and

frequency were scored independently by three industrial hygienists unaware of case/control status,

Significantly increased risk of CRF were found for exposure to lead (odds ratio 2.11 [95% CI 1.23-4.36]),

copper (2.54 [1.16-5.53]), chromium (2.77 [1.21-6.33]), tin (3.72 [1.22-11.3]), mercury (5.13 [1.02-25.7]),

welding fumes (2.06 [1.05-4.04]), silicon-containing compounds (2.51 [1.37-4.60]), grain dust (2.96 [1.24-

7.04]), and oxygenated hydrocarbons (5.45 [1.84-16.2]). The frequencies of various occupational exposures

were high among patients with diabetic nephropathy. This epidemiological study confirms previously identified

risk factors and suggests that additional occupational exposures, for which there is some other experimental

evidence, may be important in the development of CRF. The role of grain dust and the association between

occupational exposure and diabetic nephropathy merit further investigation.”

O’Carroll RE, Masterton G, Dougall N & Ebmeier KP. The neuropsychiatric sequelae of mercury poisoning.

The mad hatter’s disease revisited. Br J Psychiatry 167(1):95-98 (1995)

ABSTRACT: “BACKGROUND. the detailed effects of mercury poisoning on cognitive function, brain

anatomy and regional brain function are largely unknown. We report a case of a 38-year-old man who was

exposed to toxic levels of inorganic mercury. METHOD. Four years after exposure, the patient was assessed

using magnetic resonance imaging (MRI), single-photon emission computerised tomography (SPECT) and

detailed neuropsychological evaluation. RESULTS. The patient developed a myraid of physical and psychiatric

complaints, including stomatitis, muscle spasm, tremor, skin rash and the psychiatric syndrome known as

“erythism” (Mad Hatter’s disease). Neuropsychological evaluation revealed marked and significant deficits of

attention, concentration, particularly when under time pressure. The MRI scan was unremarkable; however,

SPECT revealed hypermetabolism of the posterior cingulate cortex. CONCLUSIONS. Mercury poisoning

appeared to result in a dysregulation of posterior cingulate cortex, which was associated with attention/

concentration deficits and marked anxiety/agitation.”

Oskarsson A, Palminger Hallen I & Sundberg J. Exposure to toxic elements via breast milk. Analyst

120(3):765-770 (1995)

ABSTRACT: “Breast milk is the ideal nutrient for the newborn, but unfortunately also a route of excretion

for some toxic substances. Very little attention has been paid to breast milk as a source of exposure to toxic

elements. The dose-dependent excretion in breast milk and the uptake in the neonate of inorganic mercury,

methylmercury and lead were studied in an experimental model for rats and mice. The transfer of mercury

from plasma to milk was found to be higher in darns exposed to inorganic mercury than to methylmercury. In

contrast, the uptake of mercury from milk was higher in the sucklings of dams exposed to methylmercury than

to inorganic mercury. Pre- acid postnatal exposure to methylmercury resulted in increased numbers and

altered proportions of the thymocyte subpopulation and increased lymphocyte activities in the offspring of mice

and also effects on the levels of noradrenaline and nerve growth factor in the developing brain of rats.

Mercury in blood and breast milk in lactating women in Sweden was studied in relation to the exposure to

mercury from fish and amalgam. Low levels were found; the mean levels were 0.6 ng g(-1) in milk and 2.3 ng

g(-1) in blood. There was a statistically significant correlation between mercury levels in blood and milk,

showing that milk levels were approximately 30% of the levels in blood. Inorganic mercury exposure from

amalgam was reflected in blood and milk mercury levels. Recent exposure to methylmercury from

consumption of fish was reflected in mercury levels in the blood but not in milk. A high lactational transfer of
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DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS 287

lead was found in rats and mice. A linear correlation was found in the dams between lead in plasma and milk

and between lead in milk and tissues of sucklings. It was also found that the bioavailability of lead in milk diets

is dependent on the casein content of milk. Thus, lead in human milk with a low casein content was absorbed

more rapidly and to a higher extent in the sucklings than lead in rat milk with a high casein content. The

excretion of lead in milk was also studied in cows after an episode of lead intoxication. A curvilinear

relationship between lead in blood and milk was found, with a sharp increase in lead levels in milk at blood lead

levels above 200-300 mu g kg(-1). Lead levels in human breast milk and blood were studied in Sweden. The

mean levels of lead were 0.8 mu g l(-1) in milk and 33 mu g l(-1) in blood. This can be compared with a

reported mean value of 62 mu g l(-1) in milk from women living close to a smelter in Mexico. There was no

correlation between lead levels in blood and milk in the Swedish study. However, significantly higher levels of

lead in milk were found in women living close to a metal smelter as compared with women from a control

area.”

Perlingeiro RCR & Queiroz MLS. Measurement of the respiratory burst and chemotaxis in polymorphonuclear

leukocytes from mercury-exposed workers. Human & Experim Toxicol 14:281-286 (1995)

ABSTRACT: “The chemotactic and nitroblue tetrazolium reducing activities of neutrophils from 48 mercuryexposed workers were examined and compared with those of non-exposed, age- and sex-matched individuals.

At the time of testing, the exposed population had a mean (+/- s.d.) urinary mercury concentration of 24.0 +/-

20.1 ug/g creatinine and in 44 of these workers urinary mercury levels were below the accepted threshold

level (TLV) of 50 ug/g creatinine. The two neutrophil functions were significantly reduced in the mercuryexposed workers compared with the controls. In 28 of these workers, chemotaxis was re-evaluated 6 months

later. During the intervening 6 months, the level of hygiene was improved throughout the plant and urinary

mercury concentrations were determined monthly in each worker. Des pite a significant reduction in urinary

mercury concentrations, neutrophil migration did not return to within the normal range. These results suggest

the “safe” level mercury exposure may lead to impairment of netrophil function.”

Ritchie KA, MacDonald EB, Hammersley R, McGowan DA, Dale IM & Wesnes K. Psychomotor testing of

dentists with chronic low level mercury exposure. J Dent Res 74:420 IADR Abstract 160 (1995)

ABSTRACT: “There is still widespread concern about possible ill effects of chronic low-level mercury

exposure on dentists, staff and patients. 20 experienced general practioners (mean age 41), and 19 first year

post-qualification dentists (mean age 23), were tested, as were a control group of 40 doctors, 20 “older” (mean

age 46) and 20 “younger” (mean age 28). A computerised battery of psychomotor tests developed for drug

studies by Cignitive Drug Research was used., along with a questionnaire on age, sex, alcohol consumption,

regular medication, general health (supplemented by the 12-question version of the General Health

Questionnaire), and some aspects of practice procedure, includingany recent mercury spillage. Their urine

samples were analysed by cold atomic absorption spectroscopy and related to creatinine content as a measure

of urine concentration. The robertson Institute for Biostatistics (University of Glasgow), analysed data from

the 42 measurements from the 8 tests along with results of the questionnaire and of the urine testing. The

median mercury / creatinine ratios (nmol/mmol) for older dentists were 3.65 (range 1.4 - 17.6), younger

dentists 1.8 (0.7 - 16.6), older controls 0.95 (0.2-15), and younger controls 1.25 (0.5 - 6.1). Three older and

one young dentist had levels above the 5 mg/mmol cretinine considered to be the normal background level.

Older dentists scored faster Mean Reaction Times, (t-test, p<0.02) and poorer Mean Immediate, (p<0.05), and

Mean Delayed, (p<0.05), Word Recall, than the other groups, but there were no differences in the tests of

Number Vigilance, Choice Reaction Time, Spatial Memory, Memory Scanning, or Word Recognition. No

differences were shown in GHQ responses. Older dentists had faster reaction times, perhaps due to

occupational experience, but impaired memory retrieval, which could not be related to any confounding factors,

and could be due to chronic low level mercury exposure. The CDR testing system is suitable for larger scale

studies of effectc of mercury exposure on dentists.”
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288 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

Salonen JT , Sepp:anen K, Nyyss:onen K, Korpela H, Kauhanen J, Kantola M , Tuomilehto J, Esterbauer H,

Tatzber F & Salonen R. Intake of mercury from fish, lipid peroxidation, and the risk of myocardial infarction

and coronary, cardiovascular, and any death in eastern Finnish men. Circ 91(3):645-655 (1955)

ABSTRACT: “ BACKGROUND: Even though previous studies have suggested an association between high

fish intake and reduced coronary heart disease (CHD) mortality, men in Eastern Finland, who have a high fish

intake, have an exceptionally high CHD mortality. We hypothesized that this paradox could be in part explained

by high mercury content in fish. METHODS AND RESULTS: We studied the relation of the dietary intake of

fish and mercury, as well as hair content and urinary excretion of mercury, to the risk of acute myocardial

infarction (AMI) and death from CHD, cardiovascular disease (CVD), and any cause in 1833 men aged 42 to

60 years who were free of clinical CHD, stroke, claudication, and cancer. Of these, 73 experienced an AMI in

2 to 7 years. Of the 78 decreased men, 18 died of CHD and 24 died of CVD. Men who had consumed local

nonfatty fish species had elevated hair mercury contents. In Cox models with the major cardiovascular risk

factors as covariates, dietary intakes of fish and mercury were associated with significantly increased risk of

AMI and death from CHD, CVD, and any death. Men in the highest tertile (> or = 2.0 micrograms/g) of hair

mercury content had a 2.0-fold (95% confidence interval, 1.2 to 3.1; P = .005) age- and CHD-adjusted risk of

AMI and a 2.9-fold (95% CI, 1.2 to 6.6; P = .014) adjusted risk of cardiovascular death compared with those

with a lower hair mercury content. In a nested case-control subsample, the 24-hour urinary mercury excretion

had a significant (P = .042) independent association with the risk of AMI. Both the hair and urinary mercury

associated significantly with titers of immune complexes containing oxidized LDL. CONCLUSIONS: These

data suggest that a high intake of mercury from nonfatty freshwater fish and the consequent accumulation of

mercury in the body are associated with an excess risk of AMI as well as death from CHD, CVD, and any

cause in Eastern Finnish men and this increased risk may be due to the promotion of lipid peroxidation by

mercury.”

Sato K, Kusaka Y, Yanagihara M , Ueda K, Mori T & Miyakoshi S. :An epidemiological study of factors

relating to mercury sensitization: Arerugi 44(2):86-92 (1995) (In Japanese with Engl abstr)

ABSTRACT: “We investigated factors relating to mercury sensitization in 156 medical students (mean age

22.7 +/- 2.4, mean +/- S.D., male 113, female 43). Their allergic symptoms, lifestyles and family histories were

studied by questionnaire. Patch tests were performed on them with HgCl2 (0.05%aq.), NiSO4 (5%aq.), PPD

(2%pet.) and urushiol (0.01%pet.). Anti-dermatophagoides and anti-cryptomeria pollen IgE antibodies in serum

were also measured. While the positive rates of urushiol, nickel and PPD were 11.1%, 5.1% and 2.6%,

respectively, that of mercury was as high as 12.8%. Each allergen specific antibody positivity and past

histories of allergic diseases were not associated with mercury sensitization (by the chi-square test). Mercury

sensitized students had significantly more frequently experienced eczema caused by cosmetics, shampoos,

soaps and haircreams (by the chi-square test, p < 0.005). They also had significantly more teeth treated with

metals compared to the controls (one-tailed t-test, p <0.05). And their urinary mercury concentrations were

significantly higher than those of the controls (one-tailed t-test, p < 0.05). These findings suggest that mercury

sensitization is associated with exposure to mercury in the living environment.”

Saxe SR, Snowdow DA, Wekstein MW, Schmitt FA & Wekstein DR. Amalgam and Elderly Mental Function.

J Dent Res 74:75 AADR Abstract 510 (1995)

ABSTRACT: “Dental amalgam restoration surfaces release mercury (Hg), a neurotox, when mildly abraded

such as from chewing. Possible neuropsychological effects of such Hg relese have been alluded to but have

not been well assessed. This study investigated whether a relationship exists between number and surface

area of occlusal amalgam restorations and cognitive function in older women. Catholic sisters (nuns) (n=122)

aged 75-102 years who lived in the same residential complex with an on-site dental office were given a

selected battery of 8 standarized neuropsychological tests. Number and surface area of occlusal amalgams
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were determined using bite registrations, an intra-oral video camera and a Kontron image analyzer computer

system. Of the 122 sisters, 22 were dentate but had no amalgam (Grp. I) who were compared to 27

edentulous (Grp.II), 43 with 1 to 99 sq. mm of occlusal amalgam surface (Grp III) and 30 with 100 or greater

sq. mm (Grp. IV). Age and education-adjusted differences in Word Recall outcome scores showed that

compared to Grp. I, Grp. II was 1.3 (95% CI -0.3,2.9) p=0.12; Grp. III was 0.6 (Cl -1.0,2.2) p=0.43; Grp. IV

was 1.1 (Cl -0.6,2.9) p=0.20. Remaining tests also showed no adverse effects in grps. II, III and IV. The older

women studied showed no difference in mental function testing regardsless of the presence and extent of

occlusal surface amalgam.”

Skare I. Mass Balance and Systemic Uptake of Mercury Released from Dental Amalgam Fillings. Water, air,

and soil pollution 80(1-4):59-67 (1995)

ABSTRACT: “The release of mercury (Hg) from dental amalgam fillings has been verified by several

authors. In this study, the emission rate of Hg0-vapor from the oral cavity (O-Hg) and the urinary Hgexcretion rate (U-Hg) have been studied with 34 healthy individuals. In ten cases, the urinary excretions of

silver (U-Ag) and the fecal excretions of Hg and Ag (F-Hg, F-Ag) were also monitored. All variables, except

U-Ag, were significantly related to the load of amalgam. According to this study, an individual with a moderate

lode of amalgam, i.e. 30 restored surfaces, is predicted to exhibit the following emission rates: O-Hg=22, UHg=3, F-Hg=60 and F-Ag=27 ug/d (d=24 hours), consistent with a gross mass balance for Hg of

approximately 60 ug/d. The corresponding systemic uptake of Hg was estimated to 12 ug/d based on external

data relating air Hg0-exposures to urinary Hg-excretions. The worst case individual showed a gross mass

balance of 200 ug Hg/d connected to a systemic uptake of 70 ug Hg/d. These values were compared to the

average intake of total-Hg by a Swedish diet (2 ug/d) and to the WHO’s tolerable value for intake of total Hg

by food (45 ug/d). Upscaled to the entire Swedish population (8 mill.), the data suggests a fecal/urinary

emission to the environment of 100 kg Hg yearly originating from a population load of amalgam fillings

containing 90,000 kg of Hg.”

Smart ER, Macleod RI & Lawrence CM. Resolution of lichen planus following removal of amalgam

restorations in patients with proven allergy to mercury salts: a pilot study. Br Dent J 178(3):108-112 (1995)

ABSTRACT: “Thirteen patients with symptomatic oral lichen planus had been shown by patch testing to be

allergic to ammoniated mercuric chloride. Replacement of amalgam restorations in these patients effected an

improvement in all but one case. In some cases the resolution of symptoms was dramatic following the

replacement of one or two fillings. The authors feel that the removal of all amalgam fillings need not be

necessary except in the most intractable case.”

Soederstroem S, Fredriksson A, Dencker L & Ebendal T. The effect of mercury vapour on cholinergic

neurons in the fetal brain: studies on the expression of nerve growth factor and its low- and high-affinity

receptors. Developmental Brain Research 85(1):96-108 (1995)

ABSTRACT: “The effects of mercury vapour on the production of nerve growth factor during development

have been examined. Pregnant rats were exposed to two different concentrations of mercury vapour during

either embryonic days E6-E11 (early) or E13-E18 (late) in pregnancy, increasing the postnatal concentration of

mercury in the brain from 1 ng/g tissue to 4 ng/g tissue (low-dose group) or 11 ng/g (high-dose group). The

effect of this exposure in offspring was determined by looking at the NGF concentration at postnatal days 21

and 60 and comparing these levels to age-matched controls from sham-treated mothers. Changes in the

expression of mRNA encoding NGF, the low- and hogh-affinity receptors for NGF (p75 and p140 trk,

respectively) and choline acetyltransferase (ChAT) were also determined. When rats were exposed to high

levels of mercury vapour during early embryonic development there was a significant (62%) increase in

hippocampal NGF levels at P21 accompanied by a 50% decrease of NGF in the basal forebrain. The

expression of NGF mRNA was found to be unaltered in the dentate gyrus. The expression of p75 mRNA was
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290 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

significantly decreased to 39% of control levels in the diagonal band of Broca (DB) and to 50% in the medial

septal nucleus (MS) whereas no alterations in the level of trk mRNA expression were detectable in the basal

forebrain. ChAT mRNA was slightly decreased in the DB and MS, significantly in the striatum. These findings

suggest that low levels of prenatal mercury vapour exposure can alter the levels of NGF and its receptors,

indicating neuronal damage and distributed trophic regulations during development.”

Stoz F, Aicham P, Janovic S, Steuer W & Mayer R. Ist ein generelles Amalgam-Verbot gerechtfertigt?

Untersuchungen an M:uttern und ihren Neugeborenen. (Is a generalized amalgam ban justified? Studies of

mothers and their newborn infants) Z Geburtshilfe Perinatol 199(1):35-41 (1995) (In German with Engl Abstr)

ABSTRACT: “To measure the Hg-contamination from amalgam as well as other exposures to mothers and

their newborns 185 women with tooth filling surfaces from 0 to 780 mm2 were examined. The Hg-values of

mother and child at a time showed a highly significant correlation with a median value from 0.4 resp. 0.5

microgram/Hg/l. Obviously, the placenta has a retention capability with up to 10 times higher Hg-values and a

low positive correlation to the amalgam surfaces. There was no relationship between the blood values of the

women and the children and the size of the surfaces of the amalgam fillings. Opposite to this a high

consumption of fish led to higher Hg-values in the umbilical cord blood, this even in children with mothers

without amalgam fillings. Other exposures through working conditions (i.e. dental assistant) or living

environment did not lead to higher values. Symptoms of diseases such as headaches, allergies, eczemas

appeared with those patients who had amalgam fillings as well as those in the group without amalgam fillings.

All women gave birth to healthy children. With all necessary caution concerning contamination with heavy

metals during pregnancy some of today’s panic inducing portrayals do not seem justified.”

Tandon L, Kasarskis EJ & Ehmann WD. Elemental imbalance studies by INAA on extraneural tissues from

amyotrophic lateral sclerosis patients. J Radioanal Nuclear Chem 195(1):13-19 (1995)

ABSTRACT: “Human kidney and liver tissues were studied for generalized elemental imbalances in

amyotrophic lateral sclerosis (ALS) by instrumental neutron activation analysis (INAA). Iron was significantly

increased (p < 0.05) in ALS kidneys and Co and Fe(marginal, p < 0.10) were increased in ALS liver compared

with their respective controls. Mercury values were almost two-fold higher for ALS kidney and 17% higher

for ALS liver as compared with their respective controls. However, the Hg data exhibited large variations and

ALS-control differences were not significant. Data from the present study are discussed with reference to the

role of metallothioneins (MT) in ALS, and a possible linkage between a free radical mediated mechanism and

degeneration of cells in ALS is also explored.”

Tibbling L, Thuomas K-A, Lenkei R & Stejskal V. Immunological and brain MRI changes in patients with

suspected metal intoxication. Int J Occup Med Toxicol 4(2):285-294 (1995)

ABSTRACT: “ Thirty-four patients with CNS and systemic symptoms suggestive of intoxication from dental

amalgam were examined with magnetic resonance imaging (MRI) of the brain (n=32) and with a Memory

Lymphocyte Immuno Stimulation Assay, MELISA, (n=17). Lymphocyte phenotype was analysed with flow

cytometry (FC) in 22 of the patients. One hundred twenty age-matched patients without CNS symptoms

served as controls for the MRI study, seventy-seven healthy subjects with dental amalgam fillings served as

controls for the MELISA test, and seventy-five clinically healthy subjects were controls for lymphocyte

phenotype determination. Pathological MRI findings were found in 81 % of the patients, most of them with

signs of degeneration in the basal ganglia, but in none of the controls. The lymphocyte phenotype determination

was pathological in 58 %. The MELISA showed pathological findings in 88 % of which 60 % with immune

reactions to mercuric chloride. 62 % of the patients had some kind of atopic disease. 35 % suffered from

levothyroxine-treated hypothyreosis. A high rate of immunopathies and objective signs of immunological

reactions in the majority of the patients with MRI changes in the brain suggests that immunological

mechanisms may play an important role in the development of the lesions.”
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Tulinius AV. Mercury-dental amalgam fillings and intellectual abilities in Inuit school children in Greenland. Arct

Med Res 54(2):78-81 (1995)

ABSTRACT: “The hair mercury concentration of 125 Greenland pupils aged 12 to 17 was recorded and

compared with the pupils’ marks in selected school subjects. Mercury values ranged from 0.2 to 15.9

microgram per gram (ug/g) and 20% of the pupils had more than 6 ug/g. There was no correlation between a

high mercury concentration score and poor results in school. Correlation of the number of dental amalgam

fillings with mercury concentration showed a weak but no significant relation. Eating habis were significantly

correlated with mercury concentration. Girls had a significantly higher number of amalgam fillings than boys,

and had a significantly higher mercury concentration. Modern Inuit and the mummified Qilaqitsoq Inuit from

the 15th century had largely identical levels of mercury in the hair irrespective of today’s higher exposure to

global environmental contamination. This is believed to result from a change in eating habits away from the

traditional Greenland food towards a more continental diet.”

Warfvinge K, Hansson H & Hultman P. Systemic autoimmunity due to mercury vapor exposure in genetically

susceptible mice: dose-response studies. Toxicol Appl Pharmacol 132(2):299-309 (1995)

ABSTRACT: “Six groups of genetically mercury-suspectible female SJL/N (H-2(5)) mice were exposed to

mercury vapor at a concentration of 0.3-1.0 mg Hg/m3 air for 0.5-19 hr/day 5 days a week for 10 weeks. The

absorbed doses calculated to be between 75 and 2365 ug Hg/week/kg body wt (ug Hg/week/kg). The

correlation between the dose and the concentration of Hg in Kidney, spleen, and thymus was significant (p

<0.0001; Spearman’s rank correlation test). The lowest observed adverse effect level (LOAEL) for serum

IgG antinuclear antibodies (ANoA) was 170 ug Hg/week/kg, corresponding to a renal mercury concentration

of 4.0+/-0.76 ug Hg/g wet wt. The correlation between the absorbed dose and the ANoA titer was highly

significant (p <0,0001; Spearmen’s rank correlation test), and all mice were ANoA-positive at a dose of 480 ug

Hg/week/kg. High-titer ANoA targeted the nucleolar 34-kDa protein fibrillarin. The LOAEL for B-cell

stimulation, measured as an increase in serum IgG2a and IgG1 concentrations, was 360 ug Hg/week/kg, but

the increase was fivefold higher and also included IgE at a dose of 690 to 2365 ug Hg/week/kg. The serum Ig

concentrations peaked after 2-4 weeks and then slowly declined but, except for IgE, remained significantly

increased during the entire exposure time. Glomerular, mesangial IgG immune complex (IC) deposits,

accompanied by systemic vessel wall IC deposits, were first detected at a dose of 480 ug Hg/week/kg, The

mesangium also showed increased titers of IgM IC deposits and complement factor C3c. The correlation

between the absorbed dose, and the individual titer of IgG, IgM, and C3c, was highly significant (p <0.0001;

Spearmen’s rank correlation test). In conclusion, mercury vapor efficiently induced an autoimmune syndrome

in genetically suceptible mice, and the LOAEL for adverse effects varied in the order ANoA < B-cell

stimulation < IC deposits. Comparing the body burden of mercury in mice at the LOAEL for autoantibodies

with the body burden in populations of occupationally exposed humans suggests that the safety margin may be

narrow for genetically suspectible individuals.”

Zaichick VYe, Tsyb AF & Vtyurin BM. Trace elements and thyroid cancer. Analyst 120(3):817-821 (1995)

ABSTRACT: “To evaluate the importance of trace amounts of elements in thyroid cancer etiology and

diagnostics, instrumental neutron activation analysis has been used to estimate Ag, Co, Cr, Fe, Hg, I,Rb, Sb, Sc,

Se, and Zn concentrations in malignant and benign thyroid nodules as well as in apparently intact paranodular

thyroid tissue. Resected material from 135 patients was obtained from operations. Forty-five cancer cases

were diagnosed and the rest were of benign nodules. The thyroid glands of 65 people, 53 male and 12 female,

who died and unexpected death or committed suicide, were used as a control group. Trace element contents of

the International Atomic Energy Agency reference material H-4 (animal muscle) were analysed simultaneously

with the thyroid tissue in order to evaluate the accuracy of the obtained data. No dependence of trace element
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292 DRAFT WISCONSIN MERCURY SOURCEBOOK: DENTISTS

contents on sex and age (14-80 years) was found for normal thyroids. In paranodular tissue, the Ag, Co, Hg, I

and Rb contents were much higher for malignant and benign nodules than they were for the standard. There was

also a slight deficiency of Se in the nodules compared with the standard. This result supports the hypothesis that

the direct toxic heavy metal influence on thyrocytes plays a major role in thyroid cancer etiology, provided that an

adequate level of the defence mechanisms is absent. Iodine concentrations are 15 times lower, on average, in

malignant compared with benign nodules. It is also shown that the radio between the iodine concentration in

nodular and paranodular tissue can be used for in vivo thyroid cancer diagnostics.”