The Materials Flow of Mercury in the Economies

 of the United States and the World

By John L. Sznopek and Thomas G. Goonan

U.S. Geological Survey Circular 1197 

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

Bruce Babbitt, Secretary

U.S. Geological Survey

Charles G. Groat, Director

Version 1.0

Any use of trade, product, or firm names in this publication

is for descriptive purposes only and does not

imply endorsement by the U.S. Government

.

Published in the Central Region, Denver Colorado

Manuscript approved for publication June 14, 2000

Edited by Lorna Carter 

Photo composition by William E. Sowers

Graphics by William E. Sowers

This report is only available on line at

http://greenwood. cr.usgs.gov/pub/circulars/c1197/
III

Contents

Abstract ................................................................................................................................................ 1

Introduction .......................................................................................................................................... 1

Acknowledgments .............................................................................................................................. 3

Mercury Flow Analysis........................................................................................................................ 3

Domestic ...................................................................................................................................... 3

Emissions to the Environment ......................................................................................... 4

Sources—1996 .................................................................................................................. 5

Sources—1990 Versus 1996 ............................................................................................ 6

Disposition—1996 ............................................................................................................. 6

Disposition—1990 Versus 1996........................................................................................ 7

Case Study—Chlor-Alkali ................................................................................................. 9

Legislation ........................................................................................................................... 10

Outlook ................................................................................................................................. 10

International ................................................................................................................................ 11

Emissions to the Environment ......................................................................................... 12

By Countries .............................................................................................................. 12

Brazil .................................................................................................................. 12

Germany............................................................................................................. 12

Japan ................................................................................................................. 12

New Guinea....................................................................................................... 12

Russia................................................................................................................. 12

Tajikistan............................................................................................................ 12

By Processes ............................................................................................................. 12

Artisanal Gold ................................................................................................... 12

Coal Combustion............................................................................................... 13

Oil and Natural Gas Combustion.................................................................... 13

Sources................................................................................................................................ 13

Disposition........................................................................................................................... 14

Trade, 1990 Versus 1996 .................................................................................................... 14

Case Study—Chlor-Alkali ................................................................................................. 15

Legislative Approaches..................................................................................................... 15

Netherlands................................................................................................................ 15

Sweden and Denmark .............................................................................................. 15

Japan........................................................................................................................... 16

Norway........................................................................................................................ 16

Brazil............................................................................................................................ 16

Russia, Ukraine, Kyrgyzstan .................................................................................... 16

Conclusions........................................................................................................................................... 17

Selected References ......................................................................................................................... 17

Appendix................................................................................................................................................ 19
IV

Figures

1. Generic materials flow diagram.......................................................................................... 2

2. Histogram showing components of U.S. apparent supply of 

mercury (1970–1998) ............................................................................................................. 3

3. Graph showing U.S. industrial reported consumption of

 mercury (1970–1997) ............................................................................................................. 4

4. Graph showing U.S. apparent supply and reported consumption of

 mercury (1970–1998) ............................................................................................................. 4

5–13. Diagrams showing:

5. Domestic flow of mercury in 1996.......................................................................... 5

6. Domestic flow of mercury in 1990: natural and incidental releases, 

and mined, recycled, and imported metal supplied to 

domestic and exported markets ............................................................................ 6

7. Domestic flow of mercury through end uses in 1996 ......................................... 7

8. Domestic flow of mercury in 1990: products manufactured, 

in use, and obsolete ................................................................................................. 8

9. 1996 mercury flow in the U.S. mercury cell sector, 

chlor-alkali industry.................................................................................................. 8

10. 1990 mercury flow in the U.S. mercury cell sector, 

chlor-alkali industry.................................................................................................. 9

11. U.S. reported consumption, production, price, and 

legislation (1970–1997)............................................................................................. 10

12 International net mercury flow, 1990 and 1996 .................................................... 14

13. Global mercury flow by use, 1990 versus 1996 .................................................... 14

Tables

1. Legislation and programs affecting mercury........................................................................ 11

2. World chlorine capacity from chlor-alkali plants................................................................. 15

3. Mercury and gold production, 1991–1992 ............................................................................. 20

4. U.S. mercury imports, 1996 ...................................................................................................... 20

5. Mercury usage in the dental sector (1986–1996) ................................................................. 21

6. Mercury usage in the laboratory sector (1990–1996).......................................................... 21

7. Mercury usage in the measurement and 

control devices sector (1990–1996) ........................................................................................ 22

8. Mercury usage in the wiring devices and 

switches sector (1963–1996).................................................................................................... 22

9. Mercury content in a fluorescent lamp (1990–1996) ........................................................... 23

10. Mercury usage in the electric light sector (1991–1996)...................................................... 24

11. Mercury usage in the battery sector (1991–1996)................................................................ 24

12. Mercury usage in the chlor-alkali sector (1991–1996) ........................................................ 24

13. Reported mercury end-use categories (1970, 1980, 1996) ................................................. 25

14. Mercury usage in the “Other” sector (1992–1996) .............................................................. 25

15. Global mercury production, use, and flow, 1990 and 1996.................................................. 26
1

Abstract

Although natural sources of mercury exist in the environment, measured data and modeling results indicate that the 

amount of mercury released into the biosphere has increased 

since the beginning of the industrial age. Mercury is naturally 

distributed in the air, water, and soil in minute amounts, and can 

be mobile within and between these media. Because of these 

properties and the subsequent impacts on human health, mercury 

was selected for an initial materials flow study, focusing on the 

United States in 1990.

This study was initiated to provide a current domestic and 

international analysis. As part of an increased emphasis on materials flow, this report researched changes and identified the associated trends in mercury flows; it also updates statistics through 

1996. In addition to domestic flows, the report includes an international section, because all primary mercury-producing mines 

are currently foreign, 86 percent of the mercury cell sector of the 

worldwide chlor-alkali industry is outside the United States, there 

is a large international mercury trade (1,395 t1 in 1996), and environmental regulations are not uniform or similarly enforced from 

country to country.

Environmental concerns have brought about numerous regulations that have dramatically decreased both the use and the 

production of mercury since the late 1980’s. Our study indicates 

that this trend is likely to continue into the future, as the world 

eliminates the large mercury inventories that have been stockpiled to support prior industrial processes and products.

Introduction

Materials flow studies provide insights into the dynamics 

that affect flow, that quantity of a specific material moving from 

one medium and (or) location to another, in this case, mercury. 

These studies permit decision-makers to leverage knowledge of 

materials flow into more efficient management with respect to 

social goals. For example, policy might be directed toward minimizing environmental impact by adjusting some aspect of a particular material’s flow. Materials flow studies address the life 

cycle of materials from extraction, through processing, manufacturing, use, re-use, and disposition. Materials flow studies characterize not only the movement of materials (including losses to 

the environment), but also the stocks: a stock (inventories or 

1

t=metric tons throughout the report.

products in use) is where a specified material resides, relatively 

unaltered, for a period of time. For more information on materials flow studies, see URL http://minerals.usgs.gov/minerals/

mflow/.

Mercury was selected for study because of its demonstrated 

toxic effects on the environment and its potential for impact on 

human health. Mercury is widely dispersed throughout air, soils, 

and water. It is mobile within the environment, so any policy-oriented solution or technological advancement that limits the 

amount going into the environment could yield benefits.

A materials flow study of mercury in the United States was 

last published by the U.S. Bureau of Mines in 1994 and contained 

data through 1990 (Jasinski, 1994). This study updates the information through 1996. This year was selected because the most 

complete set of data was available, and estimations and assumptions were thus held to a minimum. In that brief span of time 

between 1990 and 1996, major changes, precipitated mainly 

through government policy, have occurred within the mercury 

lifecycle. One purpose of this report is to document those 

changes; another is to identify trends in mercury production and 

usage for the future. More recent data from 1998 confirm that 

these trends have continued.

Mercury and its compounds have a long history of human 

use. It has been found in Egyptian tombs dated back to 1500 BC. 

Cinnabar, a mercury-sulfide mineral, was used as a red pigment 

in early Egypt and China. Spiritualists associated mercury metal 

with mystic qualities, and alchemists tried to transform it into 

gold. It was used for centuries as a curative for syphilis. Modern 

uses for mercury include electrical switches, thermometers, dental amalgams, lighting (mercury vapor and fluorescent lamps), 

flow meters, batteries, fungicides, electrochemistry, catalysis, 

explosives, gold recovery, and bactericides.

Mercury is the only metal that is liquid at room temperature 

(20 ̊C). Mercury is a good electrical conductor and is highly 

resistant to corrosion. It has a high charge density to weight ratio, 

which makes mercury batteries preferable for space missions. 

Mercury is easily separated from its parent minerals through the 

application of heat, enhancing its ability to be recovered in a pure 

state. Mercury has the highest solubility in water of any metal, 

and easily vaporizes into the air; these two properties make it very 

mobile in the environment.

Mercury vapor can be carried over great distances in the 

atmosphere, and be deposited into lakes and streams. Under 

anaerobic (oxygen-deficient) conditions, deposited mercury 

undergoes biochemical change to become methylmercury. 

Methylmercury can enter and proceed through the food chain, 

bio-accumulating in fish tissue to levels that can endanger 

The Materials Flow of Mercury in the Economies of the 

United States and the World

By John L. Sznopek and Thomas G. Goonan 
2 The Materials Flow of Mercury in the Economies of the United States and the World

populations of animals and humans that feed farther up the chain. 

Government advisories, which warn consumers about mercurycontaminated fish, have become more frequent throughout both 

the industrialized and the developing world. These concerns have 

been the main impetus for greater regulatory control of mercury.

Although natural sources of mercury exist in the environment, such as mineral deposits, hot springs, and volcanoes, 

increased amounts of mercury have entered into the biosphere 

from anthropogenic (human-derived) sources. Some of the more 

significant anthropogenic mercury-emission sources include 

municipal and medical waste incineration, coal combustion, 

manufacturing process leaks, and the leaching of solid wastes in 

landfills.

In the past, management and regulatory responses to the 

growing mercury problem have generally been constrained by a 

lack of information on sources, method of transport, chemical 

interaction with the environment, and biological significance of 

mercury in the environment. However, significant research 

advances during the past decade have allowed scientists to identify, measure, and examine the important biogeochemical processes that determine the fate and biological availability of 

mercury in the environment. A detailed discussion of these issues 

is outside the scope of this study, but the following references 

may be helpful: U.S. EPA, “Mercury Study Report to Congress,” 

1997; “Mercury as a global pollutant,” in Water, Air, and Soil Pollution, v. 80, 1995; “Mercury pollution – Integration and synthesis,” edited by Carl J. Watras and John W. Huckabee, 1994; and 

“Mercury as an environmental pollutant,” in Water, Air, and Soil 

Pollution, v. 56, 1991.

A primary requirement for any materials flow analysis is 

substantiated data. Where U.S. data were unavailable because 

they were either not collected or not reported, certain calculations 

were made based on estimations and assumptions. Flow splits 

(numerical fractions into which a single flow from one stock distributes to two or more different stocks) were estimated if data 

were unavailable. In addition, approximations were made for byproduct mercury production from gold mines, mercury incorporated in lighting fixtures, and disposal splits between recycling 

and land filling. As mercury in the environment is an international issue, global interregional mercury flows were estimated 

for 1990 and 1996. Unless specifically noted, the figures in this 

study were produced using U.S. Geological Survey’s data (Mineral Commodity Summaries, 1997–1998, and Minerals Yearbook, 1995–1997). The details concerning the quantification of 

various textual and graphical parameters mentioned are contained in the Appendix.

Post-consumer

discards Waste or losses

Recycled

flow

Waste or losses

Renewable and

nonrenewable

resources

Landfills, impoundments, deep wells,

and ocean disposal

Releases to air,

land, and water

Materials Flow Cycle

Resource

supply

Production and

manufacturing Consumption

Recycling

Environment

Figure 1. Generic materials flow diagram.
Mercury Flow Analysis 3

Acknowledgments

We are very appreciative to Stephen M. Jasinski, U.S. Geological Survey mineral commodity specialist, for sharing his 

prior research, methodologies, and associated references, and to 

Robert G. Reese, U.S. Geological Survey mineral commodity 

specialist, for his assistance.

Mercury Flow Analysis

Domestic

U.S. mercury apparent supply2 is shown in figure 2 for the 

period 1970 to 1998. These data suggest three different time 

periods, characterized by different market dynamics. From 

1970 to 1986, U.S. primary mercury mine production and net 

imports contributed significant amounts to the mercury market. 

Net imports, during this first period, grew strongly from 33 percent of apparent supply in 1970 to 83 percent in 1974, and then 

decreased slowly to 58 percent in 1978. Thereafter, net imports 

plunged to 13 percent of apparent supply in 1980, remaining 

steady until 1984, when they advanced to 42 percent. The market share of U.S. primary mercury mine production was 

inversely correlated to net imports, indicating direct substitution of one for the other. Throughout this period, U.S. secondary mercury production from scrap supplied between 4 and 26 

percent of apparent supply.

 2 Apparent supply includes production (primary and secondary) + net imports + 

government stockpile releases.

The second distinct period spanned 1986–1992; it was 

characterized by a rapid decrease in U.S. apparent mercury supply, caused by legislation to eliminate mercury in batteries (54 

percent of demand for mercury in 1984, and 2 percent in 1992) 

(fig. 3). Also contributing to the reduction in apparent mercury 

supply was the elimination of mercury in paint as a fungicide 

(16 percent in 1989, and 0 percent in 1992). U.S. stockpile 

releases continued through this period, and secondary production showed little change. From 1989 through 1992, the United 

States exported mercury, most likely from industry stocks held 

to manufacture batteries and paint additives, but also from large 

U.S. Government stockpile releases (1991 and 1992). Mine 

production of primary mercury in the United States ceased in 

1991.

The third distinct historical period, from 1993 to 1998, was 

one of adjustment to current conditions where apparent mercury 

supply had bottomed out. This period is characterized by 

increases to consumer and producer stocks, increasing net 

imports, no primary mine production, and greatly expanded secondary mercury production, supported by favorable (State-level) 

legislation mandating mercury recycling.

The term “reported consumption” has a long history and 

was used in the past by the U.S. Bureau of Mines (USBM) and 

is currently used by the U.S. Geological Survey (USGS). 

Reported consumption is collected data from surveyed respondents and represents the mercury metal purchased from producers (at market prices, at time of purchase) by nonproducers. 

Distribution of U.S. mercury reported consumption among 

industrial sectors for the period 1970 through 1997 is shown in 

figure 3. This illustration demonstrates the details of the distribution of mercury among market sectors, and shows the major 

impact of curtailment of the use of mercury for batteries and 

paints, illustrating the discussion of figure 2.

1970 1974 1978 1982 1986 1990 1994 1998

-1500

-1000

-500

0

500

1000

1500

2000

2500

3000

METRIC TONS

YEAR

Stockpile release

Mine production

Secondary production

Net imports

Figure 2. Components of U.S. apparent supply of mercury (1970–1998).
4 The Materials Flow of Mercury in the Economies of the United States and the World

1970 1975 1980 1985 1990 1995

0

500

1000

1500

2000

2500

Chlor-alkali

Other

Dental

Instruments

Batteries

Switches

Lighting

Laboratory

Paint

YEAR

METRIC TONS

Figure 4 compares apparent mercury supply with reported 

consumption. If stock changes were added to apparent supply, 

the result would track more closely with reported consumption.

In figure 4, when apparent supply exceeds the reported consumption line, inventories of producers and consumers are 

increased that year, and where the apparent supply fails to reach 

the reported consumption line, inventories are depleted. 

Between 1984 and 1989, mercury apparent supply never 

achieved the full reported consumption level; indicating continual consumer and producer inventory declines3

. During 1991 

and 1992, when net imports were negative (exports are greater 

than imports) and reported consumption was leveling off from 

the steep decline experienced between 1983 and 1991, the 

United States was actually depleting its total mercury stocks.

Emissions to the Environment

In 1996, the burning of fossil fuels emitted 76 t of mercury 

into the atmosphere, as shown in figure 54. Almost 87 percent 

3

See discussion in Appendix, p. 19, regarding how this observation may not be 

consistent for the years 1978–1988. 4Figure 5 is an update of figure 6, “Domestic flow of mercury in 1990” (Jasinski, p. 

24). Both figures address supply, demand, and emissions to the environment. 

For a detailed explanation of figure 5 flow amounts and how they were 

derived, see pages 19– 20 in the Appendix. For the purposes of this analysis, 

it is assumed that all flow amounts are 100 percent mercury.

or 66 t originated from the burning of coal. The single largest 

point source of anthropogenic mercury emissions is coal-fueled 

utility boilers used for electrical generation. Recovery of mercury presents a problem because it is present in coal in very 

small quantities, but the enormous amount of coal burned produces a large overall contribution. Oil and gas combustion, 

mainly in business and residential boilers and furnaces for 

space heating, emitted 10 t of mercury into the air. The concentration of mercury in oil and gas is even less than in coal. 

Oil and gas burners are widely dispersed, small, and the stacks 

are generally uncontrolled.

Figure 3. U.S. industrial reported consumption of mercury (1970–1997).

Figure 4. U.S. apparent supply and reported consumption of mercury 

(1970–1998).

1970 1974 1978 1982 1986 1990 1994 1998

-500

0

500

1000

1500

2000

2500

3000

METRIC TONS

YEAR

Apparent supply

Reported consumption
Mercury Flow Analysis 5

66.0

10.0

27.0

14.6

6.4

4.4

1.0

0.2

0.1

129.7

0.4

nil

13.9

Metal

exports

Net change

consumer 

stocks

Net change

producer 

stocks

Industrial

usage

Coal

combustion

Oil & natural gas

combustion

Municipal solid waste

combustion

Medical waste

combustion

Hazardous waste

combustion

Cement kiln

operation

Sewage sludge

incinerators

Non-ferrous

smelters

Landfills

Total

addition

to the 

environment

144

Secondary 

production

By-product

from gold mining

Metal

imports

Net change in

government stocks

Net change in 

mercury cells

Emissions from: Sources Destinations

446.0

340.0

0

0

45.0

125.0

372.0

851.0

309.0

65.0

Various types of waste combustors and incinerators5 emitted 54 t of mercury into the atmosphere in 1996. Two principal 

contributors were municipal waste combustors (27 t) and 

medical waste incinerators (15 t). Mercury additions to both 

municipal and medical wastes have been reduced, mainly by 

eliminating the use of mercury-containing batteries by mandate, 

and by the use of a new class of electronic medical instrumentation to replace those that formerly required mercury, for 

example, medical thermometers and blood pressure gauges. 

Hazardous waste (solid and liquid) was burned both in hazardous waste combustors and cement kilns. These sources emitted 

11 t of mercury into the atmosphere in 1996.

Several factors are at work to reduce the total mercury 

emission levels from these sources. These factors include mandated stack emission controls, similar to those for municipal and 

medical waste combustors; and closure of hazardous waste 

combustors that had been justified by subsidies to the combustors for co-generated electricity. Finally, although hazardous 

waste can be utilized in cement kilns, its use limits production, 

because the fuel value of the waste is variable and its use 

requires more control. During periods of high capacity usage, 

cement kilns run on conventional fuels.

A total of 144 t of mercury entered the U.S. environment 

from all anthropogenic sources in 1996. This is 35 percent of 

 5The terms “incinerator” and “combustor” have no technical differences and are 

incorporated in this report to follow historical usage.

the total mercury entering otherwise useful applications (417 

t). A significant amount of mercury, about 13.9 t, entered the 

environment from spills, breakage, and other leaks as mercury 

was used. Comparison of figures 5 and 6 indicates that mercury mine closures in the early 1990’s were responsible for a 

significant reduction of mercury releases to the environment 

(78 t) from the milling and roasting of mercury ores. Domestic mercury releases to the environment in 1996 decreased by 

97 t over 1990 levels, that is, 144 t (1996) versus 241 t (1990). 

Mercury releases from incineration decreased by 47 percent 

(100 to 53 t) from 1990 to 1996. This reduction took place 

because of fewer mercury-containing products entering waste 

streams and more efficient stack emission controls on incinerators. Mercury disposed of in landfills, excluding soil 

amendments6, in 1996 (295 t) was 61 percent less than in 1990 

(755 t). 

Sources—1996

As shown in figure 5, U.S. mercury sources in 1996 included 

secondary production (446 t), by-product from gold mines (65 t), 

and mercury metal imports (340 t). These sources contributed 

851 t, exceeding metal exports of 45 t, and reported consumption 

6

Sewer treatment plant sludges are applied to soils as fertilizers. Such sludges 

contain nutrient minerals, but also traces of heavy metals, including mercury.

Figure 5. Domestic flow of mercury in 1996, in metric tons.
6 The Materials Flow of Mercury in the Economies of the United States and the World

372 t by a total of 434 t. The 434 t represent an increase of 

consumer stocks of 125 t, and an increase of producer stocks of 309 

t. Secondary production of mercury, by itself, was greater than 

reported mercury industrial usage in the United States in 1996.

In 1996, no government stockpile sales or chlor-alkali mercury-cell closures took place, so no mercury entered the economy 

from those particular sources. Although there is little reason for 

government stockpile sales in the near term, future market disruptions can be expected as occasional mercury-cell closures occur 

within the chlor-alkali industry.

The chlor-alkali industry uses mercury-containing electrolysis cells as one technology to produce chlorine from chloride 

salts of sodium or potassium. Approximately 3,000 t of mercury 

resides in this mercury cell stock. Mercury cell chlorine plants are 

slowly being phased out in favor of non-mercury technologies.

Sources—1990 Versus 1996

In 1996, secondary production (446 t) was more than four 

times the level of secondary production in 1990 (mercury recovered from old scrap, fig. 6). Although no domestic, primary mine 

production of mercury occurred in 1996, 448 t was produced from 

U.S. mercury mines in 1990. The change from primary mine production to increased secondary production over the 6-year period 

is important because it eliminated a major source of mercury to 

the environment, approximately 72 t from milling and roasting, 

probably reflecting increased recovery efforts due to legislation. 

Currently, much of the recycling occurs in States that encourage 

and support recycling (see table 1).

From 1990 to 1996, there was a total trade turnaround of 591 

t, indicating a growing dependence on foreign sources for the current mercury needs of the United States. Production of mercury, 

as a by-product of gold mining operations, decreased from 114 t 

in 1990 to 65 t in 1996, a 43 percent decrease. Imports of mercury 

rose sharply from 15 t in 1990 to 340 t in 1996. On the other hand, 

mercury exports decreased dramatically from 311 t in 1990 to 45 

t in 1996.

Compared to 1990, when the U.S. Government stockpile 

released 245 t of mercury to the market, 1996 saw no such 

sales. Sales were suspended in 1994 pending the release of the 

Mercury Study Report to Congress (U.S. Environmental Protection Agency, 1997b), and have not resumed as of this writing 

(1999).

Disposition—1996

Figure 77 illustrates that in 1996, 372 t of mercury flowed 

into private stocks. Private stocks are mercury residences that are 

nongovernmental stockpiles. They are controlled by producers of 

7

 Figure 7 is an update of figure 8, “Domestic flow of mercury in 1990 – continued” 

(Jasinski, 1994, p. 25). Both figures address U.S. industrial inflows and 

outflows. For a detailed explanation of figure 7 flow amounts and how they 

were derived, see pages 20–25 in the Appendix.

Natural & incidental 

releases to air, land, and 

water excluding 

incineration of wastes 

Mercury released

from natural

emissions 

1,000

Mercury released

from combustion

of coal, oil, &

natural gas 

138

Mercury emitted

from lime & 

cement kilns &

nonferrous

smelters

25 

Loss to 

environment

163

Loss to 

environment

78

Mercury

contained

in ore

520

Milling

and

roasting

448 

Mercury imports,

metal, waste, & scrap

15

Released from 

National Defense 

& DOE stockpiles

245

Mercury recovered

from old scrap

108

Recovered at gold

mining operations 

114

Industry stocks

1/1/90

217

Unaccounted

mercury

W

Mercury mine

production

448

Mercury

exports

311

Total U.S.

supply

1,228

U.S.

demand

720

Industry

Stocks

12/31/90

197

2

4

72

Mined, recycled, and imported metal supplied to domestic and exported markets

Figure 6. Domestic flow of mercury in 1990, in metric tons (Jasinski, 1994): natural and incidental releases, and mined, recycled, 

and imported metal supplied to domestic and exported markets. W, withheld.
Mercury Flow Analysis 7

mercury metal, manufacturers of products containing mercury, 

users of mercury in other production processes (such as chloralkali plants), retail consumers, wholesale distributors, and scrap 

brokers. Private stocks include inventories (for example, ores and 

scrap, work-in-progress inventories, inventories for sale) and 

products in use (such as dental fillings, switches, fluorescent 

lamps). In 1996, 794 t flowed out of private stocks, of which 56 

percent went into secondary production to be recycled and 

returned to useful applications. The balance, 44 percent, either 

was disposed into landfills (295 t), or was lost to the air from 

incineration processes (53 t). The total unrecovered mercury (lost 

during incineration or to landfills) of 348 t represents a private 

stock-wasting rate of 5 percent in 1996.

The majority of the private mercury stock was split between 

(1) chlor-alkali plants (45 percent), at 14 locations, and (2) wiring 

devices and switches (39 percent), widely dispersed in virtually 

every facet of the economy. Should these mercury-cell chloralkali plants close, most of the associated mercury stocks could 

be easily recovered. On the other hand, recovery of the mercury 

held in electrical devices would be much more problematic, 

although in some States, such as Minnesota, companies like Honeywell offer a free recycling program for mercury-containing 

thermostats (CREST, 1995).

The chlor-alkali industry used 136 t of mercury in 1996, 

almost triple the mercury usage in the next category, wiring 

devices and switches (49 t). Except for the chlor-alkali plants, 

and wiring devices and switches, which together make up 84 

percent of private mercury stocks, all other private stocks had 

larger outflows of mercury in 1996 than inflows.

At the beginning of 1996, private stocks totaled 6,800 t of 

mercury, exceeding all U.S. Government mercury stockpiles of 

4,600 t. Together, these private sector and government stocks 

(11,400 t) represent approximately a 27-year supply of mercury 

at the 417 t level of industrial and exported demand in 1996.

Disposition—1990 Versus 1996

A nearly 50 percent reduction in total mercury flows to 

industry occurred between 1990 and 1996. The mercury flows to 

industry went from 711 t in 1990 to 372 t in 1996. Comparing 

figure 7 with figure 8, mercury flowing into all specified industrial sectors in 1996 was lower than 1990 levels: dental 30 percent; laboratory 38 percent; measurement and control devices 62 

percent; wiring devices and switches 30 percent; lighting 66 percent; batteries 100 percent; and chlor-alkali plants 45 percent.

Excluding the chlor-alkali industry’s private mercury stocks, 

which were not estimated in the 1990 report, the sum of all other 

private stocks decreased from 4,300 t in 1990 to 3,800 t in 1996, 

a compound annual stock reduction rate of slightly more than 2 

percent.

In 1990, the paint sector was still adding mercury to waterbased paints, mainly as a fungicide. In 1996, this sector does not 

appear because mercury-containing paints were banned from the 

market by legislation in 1992. In 1990, mercury-containing dry 

cell batteries used 105 t of mercury; in 1996, virtually no mercury went to dry cell batteries because of both legislation and 

technological advances.

46

25

54

16

5

3

54

16

19

101

20

16

114

794

2

7

11

3

282

31

20

41

49

11

0

136

84

Unknown

Product/process Outflows Disposition

stocks 1/1/96

End Use Inflow

Sector

Dental

Laboratory

Measurement &

control devices

Wiring devices & 

switches

Electric

lighting

Batteries

Chlor-alkali

Other

Unaccounted

Totals 372 6,800

Secondary 

production

446

Land or

landfill

295

Incineration 

loss

53

236

65

331

2,670

64

32

3,050

349

Unknown

Figure 7. Domestic product flow of mercury through end uses in 1996, in metric tons.
8 The Materials Flow of Mercury in the Economies of the United States and the World

Dental

Laboratory

uses

Measuring &

control Instr.

Wiring

devices &

switches

Electric

lighting

Paint

Batteries

Other

Chlorine &

caustic soda

Recycled

internally

170

Loss to 

environment

83

105+267 in imported batteries

500

32

1,000

1,500

100

300

800

55

Incineration

loss & 

dissipation

100

Disposed in

landfill

755 

Recycled

130

Manufacture of products Products in use—4,300 (rounded) Obsolete products

44

32

108

70

33

14

105

58

247

44

32

107

1

70

32

14

<1

<1

1

<1

3

77

4

36

26

6

60

47

36

62

2

26

14

600

55

55

Figure 8. Domestic flow of mercury in 1990, in metric tons (Jasinski, 1994): products manufactured, in use, and obsolete.

Make-up

150

Within recycle

process

134

Within cell

process

2,770

On-site

recycle 324

!996 purchases (136)

Unaccounted 101

Environmental

releases 8

Associated with

caustic product 1

Off-site recycle 7

Outflow 350

Treated and landfilled 19

Sector 

flows

Sector

inventories

324

Figure 9. 1996 mercury flow in the mercury cell process of the U.S. chlor-alkali industry, in metric tons.
Mercury Flow Analysis 9

Case Study—Chlor-Alkali

 Since 1989, the use of mercury for the production of chlorine and caustic soda (37 percent of total mercury consumption 

in 1996) has been the largest component of U.S. mercury consumption. Mercury is used in electrolytic cells (mercury cells) 

to decompose chloride compounds. During this process, small 

amounts of mercury are emitted to the air, water, and land as 

sludge and as wastewater. A detailed description and a flow diagram of this process are included in Information Circular 9412 

(Jasinski, 1994). Because mercury cells (a mature technology) 

account for a major part of total industrial usage of mercury, a 

more detailed look at the flow of mercury within this process is 

warranted.

The chlor-alkali industry employs three classes of stocks 

(inventories) that are shown in figure 98

. They include new purchases or make-up (averaging about 150 t per year during the 

1990’s) that are held in warehouses to be used to restore any 

losses from the process; an average mercury inventory (134 t) 

passing through the recycling processes within the plants; and 

an average mercury inventory cycling through mercury cells 

(2,770 t).

In 1996, Toxic Release Inventory data (1997) indicated9

that the chlor-alkali industry released approximately 8.0 t of 

8

Figure 9 (1996) and figure 10 (1990) represent inflows and outflows in the 

domestic chlor-alkali industry. For a detailed explanation of how they were 

derived, see pages 25–26 in the Appendix.

mercury directly to the environment (7.6 t to air, 0.2 t to land, 0.2 

t to water), 7 t to off-site recyclers, and 19 t to landfills. Less than 

1 t is associated with the caustic product that leaves the plant, 

most likely distributed to paper mills. Subtracting these known 

losses of 35 t from the given 1996 purchase of 136 t of mercury 

by the industry leaves a total of unaccounted mercury in 1996 of 

101 t. In 1999, the “missing” mercury continues to be the subject 

of intense scrutiny by the industry and the EPA (F. Anscombe, 

EPA, oral commun., May 7, 1999).

Comparing figure 9 (1996) with figure 10 (1990), reveals 

several trends: there were four more mercury cell chlor-alkali 

plants operating in 1990 than in 1996, and the incremental mercury inventory of the chlor-alkali industry to support those 

plants was 544 t. Mercury purchases by the chlor-alkali industry in 1990 amounted to 247 t, which were 111 t more than in 

1996 (136 t). The industry landfilled 41 t less mercury in 1996 

(19 t) than in 1990 (60 t), a 68 percent decrease. Releases and 

losses embodied in caustic product remained about the same. 

In 1990, the private stocks held by the chlor-alkali industry 

were approximately 3,600 t. These stocks had been reduced in 

1996 to 3,050 t. This difference is an overall decrease of 15 

percent, or about 2.5 percent per year. This inventory reduction 

for mercury cells most likely flowed out of the United States as 

exports, and is part of the negative trade balance in 1991 and 

1992 (fig. 2).

9

All chlor-alkali plants operating mercury cells reported except for one minor 

plant in Vicksburg, Miss.

Figure 10. 1990 mercury flow in the mercury cell process of the U.S. chlor-alkali industry, in metric tons; n.a., not applicable.

Make-up

275

Within recycle

process

153

Within cell

process

3,170

On-site

recycle 369

1996 purchases (247)

Unaccounted 177

Environmental

releases 9

Associated with

caustic product 1

Off-site recycle n.a.

Outflow 429

Treated and landfilled 60

Sector 

flows

Sector

inventories

369
10 The Materials Flow of Mercury in the Economies of the United States and the World

The chlor-alkali industry has been closing some mercury 

cells and tightening mercury flow controls on the remaining 

operational cells. No new mercury cell plants are being constructed. New, more efficient, and less costly technologies have 

been available for a long time, and they are being installed 

where new chlorine capacity is needed. However, some very 

efficient, large-capacity mercury cell operations still exist and 

will remain operational into the foreseeable future.

Legislation

Figure 11 illustrates time series for mercury reported consumption, production, and price alongside dates of regulatory and 

control legislation. Even though numerous regulations are in 

place, Federal and local governments are implementing new 

actions to further reduce mercury contamination of the environment from all anthropogenic sources and to limit the use and disposal of mercury. Recently established regulatory actions could 

reduce mercury emissions from municipal and medical waste 

about 90 percent by the year 2000, when proposed rules become 

effective. Table 1 lists legislation and programs that have affected 

mercury flows in the 1990’s.

Outlook

The following are examples of current actions and efforts to 

curtail the use of mercury in any nonessential and (or) substitutable application:

♦ The Chlorine Institute (Report to EPA, 1998) has committed to a 50 percent reduction of mercury used in the 

chlor-alkali industry by 2005. This will initially occur 

through tighter controls over mercury cycling within 

mercury-cell plants, and eventually, the closing of these 

plants will shift large private stocks into the market 

supply line.

♦ Under the Clean Air Act, EPA has established mercury 

emissions limits (1) for municipal waste combustors, 

which should result in a 90 percent decline from 1990 

levels by 2000, and (2) for medical waste incinerators, 

which should result in a 95 percent decline from 1990 

levels by 2002.

♦ The EPA and the American Hospital Association agreed 

to establish several goals regarding waste management, 

one of which would eliminate specific mercury-containing waste by the year 2005.

♦ The EPA’s Mercury Study Report to Congress (U.S. EPA, 

1997b) predicted that high deposition rates of anthropogenic mercury (from both global and domestic sources) 

will occur in the Great Lakes Region. The major factors 

contributing to this phenomenon are proximity to sources 

and local climate. The increasing concern regarding 

mercury contamination within the Great Lakes Basin was 

the impetus for an international agreement between the 

Governments of Canada and the United States. The 

agreement sets a goal to significantly reduce the human 

use and release of mercury from anthropogenic sources 

in the Great Lakes Basin by 2006.

Figure 11. U.S. mercury reported consumption, production, price, and legislation (1970–1997).

 1970–Clean Air Act authorized EPA to set national standards for hazardous air pollutants.

 1971–Mercury designated as hazardous pollutant.

 1972–Federal Insecticide, Fungicide, Rodenticide Act (FIFRA) cancelled many pesticides containing mercury.

 Federal Water Pollution Control Act authorized EPA to regulate mercury discharges into waterways.

 1973–Mercury designated as toxic pollutant. Standards were enacted for mercury ore processing facilities

 and chlor-alkali plants. Dumping of mercury/mercury compounds into ocean was prohibited.

 1974–Safe Drinking Water Act authorized EPA to set standards for hazardous substances in drinking water. 

 1978–Resource Conservation And Recovery Act (RCRA) established regulations for disposal of

 mercury-bearing waste.

 1980–Comprehensive, Environmental Response, Compensation, and Liability Act

 established Superfund to clean toxic waste sites.

 

 

 

Reported consumption

Price

Production

0

1000

2000

3000

1970 1973 1976 1979 1982 1985 1988 1991 1994 1997

0

300

600

900

1200

1500

METRIC TONS

1997$/FLASK

EPA banned land disposal of high mercury content wastes generated from chlor-alkali facilities.–1992

 EPA canceled registrations of last two mercury-containing fungicides at manufacturer's request.–1993

Congress suspended mercury sales from National Defense Stockpile due to EPA questions associated with–1994 

 

The Mercury-Containing and Rechargeable Battery Management Act prohibited the sales of regulated batteries –1996 

 without recyclability or disposal labels and phased out most batteries containing intentionally added mercury.

 environmental problems.
Mercury Flow Analysis 11

Table 1. Legislation and programs affecting mercury. 

Year Authority Summary 

1992 EPA - - - - - - - - - - - - - - - - - - - - Banned the land disposal of high mercury content wastes that are generated from 

the electrolytic production of chlorine and caustic soda (effective 5/8/92). 

1992 New Jersey - - - - - - - - - - - - - - - - Restricted the sale and disposal of batteries containing mercury. 

 Banned the sale of products that have cadmium, mercury, or other toxic materials 

in packaging after 1/1/93. 

1992 California and Minnesota - - - - - - Placed restrictions on the disposal of fluorescent light tubes. 

1993 EPA - - - - - - - - - - - - - - - - - - - - Canceled the registrations for the last two mercury-containing fungicides approved 

for use in the United States at the request of the manufacturer. Cancellation 

became effective 11/1/93. 

1993 Florida - - - - - - - - - - - - - - - - - - Approved emissions regulations for resource recovery plants to limit stack 

emissions of mercury. 

 Limits the release of mercury to the environment from the disposal of batteries. 

 Arkansas, Minnesota, and New Jersey. Banned the sale and distribution of mercuric-oxide button cell batteries. 

 Phase out the amount of mercury permitted in alkaline batteries. 

1994 U.S. Food and Drug Administration Set level of 1 part per million in fish as the safe maximum limit for human 

consumption. Several States, primarily in the Northeast, issued warnings 

against eating freshwater fish because of elevated levels of mercury. 

 Minnesota - - - - - - - - - - - - - - - - Prohibited the disposal of thermostats and other mercury-containing devices unless 

the mercury was removed. 

 Congress - - - - - - - - - - - - - - - - - Suspended sales from the National Defense Stockpile because of questions raised 

by the EPA as to the potential environmental problems associated with the 

release of mercury effective 7/94. 

1995 33 States - - - - - - - - - - - - - - - - Issued freshwater fish consumption advisories because of elevated levels of 

mercury contamination. 

1996 Public Law 104 – 142 - - - - - - - - The Mercury-Containing and Rechargeable Battery Management Act of 1996 was 

made law on May 13, 1996. Title I prohibited the sale of regulated batteries 

after May 1997 without a label indicating recyclability or proper disposal. 

Title II phases out the use of alkaline-manganese and zinc-carbon batteries 

containing intentionally added mercury and button cell mercuric-oxide 

batteries. 

 U.S. Coast Guard - - - - - - - - - - - Signed an agreement with the Georgia Environmental Protection Division to 

remove from Georgia’s waterways discarded zinc-air batteries containing 

mercury. 

1997 EPA, U.S. Department of Justice, U.S. 

Attorney for Arizona. 

Settled lawsuit brought by Defenders of Wildlife. The suit was concerned with 

mercury pollution of certain Arizona waterways. 

 EPA - - - - - - - - - - - - - - - - - - - - Released its 1996 summary of State-issued warnings to the public to avoid or limit

eating fish from certain water bodies (Environmental Protection Agency, 

1997b). 

 EPA - - - - - - - - - - - - - - - - - - - - Issued its report on mercury (Environmental Protection Agency, 1997c) fulfilling 

the requirements of section 112(n)(1)(B) of the Clean Air Act as amended in 

1990. 

International

Mercury presents a global issue because emissions from 

identifiable point sources, wherever they are located, find their 

way into water and air for transport across national borders. 

Legislation and regulation have been created in many countries 

to address the mercury issue and are responsible for dramatic 

decreases in mercury use, and consequently in the available 

supply of mercury-containing products. As a current, net 

importer of mercury, the United States must consider the importance of the international flow of mercury, because all of the producing mercury mines are foreign; 86 percent of the mercury 

cells of the worldwide chlor-alkali industry is outside of the 

United States; there is a large global trade in mercury (2,037 t in 

1990 and 1,395 t in 1996); and environmental regulations are not 

uniform or similarly enforced from country to country.
12 The Materials Flow of Mercury in the Economies of the United States and the World

Emissions to the Environment

There are several specific international environmental questions regarding mercury. Because People’s Republic of China 

(PRC) is the largest combustor of mercury-containing coal as well 

as being the largest importer of mercury in the world, what are the 

internal Chinese flows of mercury and their associated emissions? 

What are the impacts of the unchecked use of mercury by artisanal 

miners in Brazil, Ghana, Venezuela, Philippines, and other countries? Are the mercury-emission control levels adequate in foreign chlor-alkali plants? What are the environmental 

consequences of mercury production in Tajikistan, Kyrgyzstan, 

and the Ukraine, considering the uncertainties surrounding the 

poor level of environmental controls within the former Soviet 

Union (FSU)? Although these questions cannot be answered 

here, the following anecdotal evidence addresses the concerns.

By Countries

Brazil.—The Kayapo Indian Area is situated in the south of 

the State of Para, Brazil. A study by Antonio Barbosa, a chemist 

from the University of Brasilia, has confirmed that newborn 

Kayapo children suffer from high levels of mercury contamination—although not to a sufficiently high degree to yield classic 

mercury poisoning symptoms (as reported by Cimi–Indianist 

Missionary Council, 1998). The study showed that mercury levels in Kayapo women drop significantly during pregnancy as the 

mercury is transferred from the mother and accumulates in the 

fetus. For this reason, newborn children have higher levels of 

mercury concentration than their mothers.

Germany.—As reported by Drozdiak (1996), the Rhine 

River was considered the “sewer of Europe” for decades. Originating in the Alps, the continent’s busiest waterway absorbed pesticides from the Swiss chemical factories, potassium salts from 

Alsatian mines, and heavy metals from German industry. By 

1970, mercury and cadmium concentrations had reached very 

high levels. However, in 1995, French biologists found that 

salmon and sea trout had returned to the upper Rhine for the first 

time in 50 years. Lead, mercury, and dioxin levels have been cut 

by 70 percent since 1986 when an international commission was 

created to clean up the river. 

Japan.—According to Takeuchi (1960), effluent containing 

mercury from an acetaldehyde manufacturing plant was discharged into the small bay of Minamata, Japan. This discharge 

continued from the years before 1953, when Minamata disease 

began to occur, to September 1958. A total of 121 cases of 

Minamata disease were identified in adults, children, and fetuses. 

About half of the adults, one-third of the children, and about oneeighth of the fetal victims died. Characteristically, the children 

and adults had eaten a great amount of fish and shellfish that contained a considerable amount of mercury. From 1 ppm to 50 ppm 

were detected in some organs on a wet weight basis. In fetal 

cases, all of the mothers had eaten large amounts of seafood and 

river fish. This provided evidence that alkyl mercury penetrates 

the placental barrier in humans.

In 1959, when the causative agent of the disease was 

found to be organic mercury, the mud of Minamata Bay was 

correspondingly found to contain an extremely large amount of 

mercury. The maximum concentration (133 ppm to 2,010 ppm) 

was found near the drainage channels from the chemical plants. 

This Japanese experience served to focus world attention on 

mercury emitted to the environment.

New Guinea.—Morgan (1995) reported that the gold workings at Porgera, New Guinea, have been operational since 1990. 

In that time they have yielded more than 6 million ounces of gold, 

dumping about 40,000 cubic meters of treated tailings into the 

Porgera River each day. In tests conducted by Phillip Sherman, 

University of Tasmania, Australia, mercury concentration in the 

river water was 64 times pre-mining levels.

Russia.—In January 1995, the Arkhangelsk Pulp and Paper 

Combine of Novodvinsk, Russia, emitted as much as 16 t of mercury compounds into the Svernaya Dvina River (as reported in 

The Environmental Database [TED Case 245, 1997]). The silt 

beds of the Svernaya Dvina River were found to contain high levels of mercury salts. Contamination levels were more than 600 

times allowable concentration limits. Although the contamination was quickly taken away by high water levels and a strong 

current to the White Sea (considered to be critical Arctic habitat), 

the pulp and paper combine continues to emit mercuric substances to the river. The plant is the principal employer in the 

town, and its water treatment plant serves as the water treatment 

for the community as well as the plant, so it would be very difficult to shut down for necessary improvements.

Tajikistan.—In Tajikistan, the Shing-Mangianskaya mountain range contains many antimony-mercury, gold-sulfides, and 

gold-rare metal mines (as reported by Baratov and Skochilov, 

1996). Wastes from these mines as well as natural background 

materials from these mines have contributed large quantities of 

mercury and other metals to the Zeravshan River. In the 

Iskanderkul-Yagnobsky region of that range, which largely specializes in mercury-antimony mining, two areas are notably polluted with mercury, antimony, arsenic, lead, and possibly 

thallium. The largest area consists of the Jijikrut mine and the 

Anzob Processing Facility situated in the middle stretch of the 

Yagnob River. This mine and its processing facility have been 

operational for more than 30 years. During this period, several 

million metric tons of mercury-antimony mining waste have been 

accumulated and occasionally washed into the river. In the second area, around the Konchoch-Skal mine, several hundred thousand metric tons of mercury-antimony waste have accumulated, 

and considerable amounts have washed into the Konchoch River.

By Processes

Artisanal Gold.—Artisanal small-scale gold mining of 

placer deposits occurs mostly in developing countries. Examples 

include Brazil, Venezuela, Colombia, Guyana, and Suriname, 

which border the Guyana Shield in South America; the Philippines and New Guinea in Oceania; and Nicaragua in Central 

America.

In Brazil, the amount of mercury entering the environment 

was estimated at about 200 t/yr [Trade and Environment Database (TED) case 132]. As described in TED case 132, gold 
Mercury Flow Analysis 13

recovery is performed by removing sediments from river bottoms 

and adjacent areas and feeding them through a number of mercury-coated sieves. The mercury amalgamates with the gold in 

the sediments, separating the gold from the rest of the material. 

Considerable amounts of mercury remain in the gold-depleted 

soil, and much of this finds its way into the rivers. The gold-mercury amalgam is then retorted. Heat drives off the mercury, leaving the gold product. While most of the mercury condenses and 

is recovered, some of this mercury is emitted to the air, where it 

resides for a time before being deposited on nearby land or water 

surfaces through precipitation. Mercury deposited on land ultimately reaches streams and rivers through runoff. Roughly 1.0 

kilogram of mercury enters the environment for every kilogram 

of gold produced by artisans (Farid and others, 1991). Another 

estimate according to research by Veloso de Araujo (1995), in the 

Alta Floresta area, State of Mato Grosso, Brazil, was that a typical 

month’s gold production of 230 kilograms (kg) emitted 240 kg of 

mercury to the atmosphere as elemental mercury vapor, and 60 kg 

of mercury into rivers.

Coal Combustion.—On a worldwide basis, coal is the most 

widely used primary fuel, accounting for approximately 37 percent of total fuel used for electricity production (U.S. Department 

of Energy, 1998). The amount and percentage of global mercury 

contributions originating from the burning of fossil fuels such as 

coal are unknown. If the rest of the world parallels the United 

States with respect to mercury emissions, then coal burning may 

be the single largest anthropogenic source of mercury to the 

atmosphere. Although all countries recognize that burning coal 

can degrade the environment, not all have pursued or are actively 

implementing methods to significantly reduce emissions.

Canada, most European countries, and Japan are widely recognized as having strict regulations limiting emissions from coalfired plants. Although these regulations are not specifically targeted at reductions in mercury emissions at this time, some of the 

emission control technologies currently employed prevent nearly 

one-half of the mercury contained in coal from being emitted to 

the atmosphere (Chu and Porcella, 1995). As stricter regulations 

are implemented and as mercury is targeted, mercury contributions to the environment from these sources should decrease. 

Some countries, such as PRC, India, Russia, and other 

countries of the FSU, are taking some measures to reduce emissions from coal burning, but they have not been very effective. 

Russia, other countries of the FSU, and some other countries in 

Eastern Europe have actually decreased coal burning, in part 

because of depressed economies, but also because of substituting 

natural gas for coal in some utility plants (Mining Journal, 

1997). As industrializing countries increase coal burning, but 

allow pollution controls to lag far behind, emissions to the environment, including mercury, will increase. PRC uses coal to produce nearly 80 percent of its electrical energy. Chinese coal, in 

general, contains about the same amount of mercury as U.S. 

coals; however, preliminary studies of coals burned in other 

countries indicate that mercury can be as much as 10 times 

higher (Robert Finkelman, USGS, oral commun., 1998). At current growth rates, PRC will continue to be the largest coal-burning nation in the world. 

A broad estimate of mercury emissions from coal burning 

could be made. A global study would have to consider average 

mercury contents and destination of coal shipments, identify significant coal combusting facilities, and identify recovery technologies used. A detailed estimate of global mercury 

contributions from coal combustion requires collection and analysis of data from individual coal-fired utility plants and industrial boilers throughout the world. The USGS is planning to 

undertake a study that will collect information and estimate 

quantities and composition of air pollution produced through 

coal combustion in the United States. An examination of mercury emissions will be included in that study (Robert Finkelman, 

USGS, oral commun., 1998).

Oil and Natural Gas Combustion.—On a worldwide basis, 

gas and oil are the second and third most widely used primary 

fuels, accounting for approximately 16 percent and 10 percent of 

total fuel used for electricity production, respectively (U.S. 

Department of Energy, 1998). The top five consumers of oil for 

generating electrical power include the United States, Japan, Russia, PRC, and Germany. Studies have shown that the oil refining 

process also releases mercury (Akelsson, 1998). Oil burning is a 

contributor to mercury emissions on a global basis, but much less 

than coal. 

Burning natural gas to generate electricity is not a significant 

mercury emissions factor on a worldwide basis. In the United 

States, the mercury emissions rate from burning natural gas is relatively low, contributing approximately 0.1 percent of total U.S. 

mercury emissions. The net effect of the substitution of natural 

gas for coal to produce electricity should result in lowering atmospheric loading of mercury. As in the case of coal and oil, data are 

insufficient to provide an estimate of global mercury emissions 

from natural gas-fueled plants.

Although the mercury content of natural gas is generally 

believed to be comparatively low, there are exceptions. Approximately 6–8 t of mercury is recovered annually from North Sea 

gases processed in the Netherlands (Maxson and Vonkeman, 

1996). High levels of mercury are also known to exist in natural 

gas burned in Germany, but the mercury is not recovered. These 

two examples illustrate the need for further research into the 

small-scale mercury content of natural gas and emissions from its 

combustion.

Sources

Presently, the world-class, producing primary mercury 

mines are located in Algeria, PRC, Kyrgyzstan, and Spain. 

(Unless noted, the production numbers in this section are from 

the Gobi Report, 1998 (see Appendix, p. 26).) Before the worldwide collapse of mercury markets in the early 1990’s, Italy, 

Mexico, Slovakia, Slovenia, and Turkey were all active minor 

producers. Although none of these countries are presently producing mercury from primary mines, each retains significant 

reserves.

The Western European region was the world’s largest mercury supplier in terms of net trade in 1996 (1,141 t). Spain, the 

largest producer within this area, provided 92 percent of this 

region’s total output. The FSU, principally the nations of Kyrgyzstan, Tajikistan, Russia, and Ukraine, was the world’s second 

largest supplier of mined mercury (785 t in 1996). Northeast Asia 

(PRC, Japan, and Korea) has widely scattered but extensive 
14 The Materials Flow of Mercury in the Economies of the United States and the World

mercury reserves. In 1996, 508 t of mercury was produced from 

mines in the PRC. Algeria produced 347 t of mercury from its 

mines in 1996; this accounted for all of Africa’s production.

Some mercury is produced as a by-product of gold production, for example, in Mexico. Mercury is also produced as a byproduct of zinc production. Finland started by-product mercury 

production from zinc operations in 1971 (Roskill Information 

Services, Ltd., 1990), and produced 88 t in 1996 as reported in the 

USGS Minerals Yearbook, 1998.

Disposition

Approximately 40 percent of the mercury produced in 1996 

was used in the world’s chlor-alkali industry (1,344 t). Western 

Europe, with the world’s largest reservoir of mercury-cell chloralkali capacity, consumed 631 t of mercury just for that purpose 

in 1996. North America, Eastern Europe, and India/Pakistan 

were also significant users of mercury (136, 184, and 133 t, 

respectively) for chlorine production. North America, Western 

Europe, and northeast Asia were the principal economies using 

mercury (a total of 860 t, 81 percent of global manufacturing) for 

the production of mercury-containing goods.

The international use of mercury for chlor-alkali production 

decreased for the period 1990–1996 by 33 percent, and for mercury-containing products by 42 percent. Estimated mercury use 

by small-scale gold miners in Brazil decreased from 200 t in 

1990 to 100 t in 1996. Mercury use by gold miners in other 

developing countries is probably significant based on anecdotal 

evidence, but is not quantifiable at this time. Stock changes in 

the world were extensive both in 1990 and 1996 (25 percent of 

their respective years’ production). Besides the United States, 

Western Europe seems to be the only region that is actively 

reducing mercury stocks. On the other hand, PRC has apparently been adding mercury to its stockpiles in levels far in excess 

of their own needs.

Trade, 1990 Versus 1996

Major net mercury exporters in 1996 included Western 

Europe, the FSU, and Africa. Major net mercury importers in 

1996 included Asia, Eastern Europe, and South America. These 

net trade flows to and from various regions of the world are displayed in figure 12, which also illustrates the 32 percent decrease 

in worldwide mercury trade from 1990 to 1996.

Figure 13 presents a slightly more detailed picture of global 

mercury demand. Global production of mercury in 1996 (3,337 

t) decreased by 2,019 t (38 percent) over 1990 levels (5,356 t).

Figure 12. 1990/1996 international net mercury trade flow, in metric tons.

Eastern 

Europe

Western 

Europe

South

America

North 

America

Asia

Africa Middle

East

Former

Soviet

Union

China

India

Other

164

208

175

10

757

932

862

214

330

96

474

201

170

145

50

682

692

531

179

104

178

196

1990

Global

production

5,356

1996

Global

production

3,337

Chlor-alkali

2,003

Products

1,818

Artisanal gold 200

Stocks

1,335

Chlor-alkali

1,344

Products

1,061

Artisanal gold 100

Stocks

832

Figure 13. Global mercury flow by use, 1990 versus 1996, in metric tons.
Mercury Flow Analysis 15

Case Study—Chlor-Alkali

Table 2 reports data from the Chemical Marketing Association, Inc. (1999) showing 1992 and 1997 world chlorine production capacities.10 The following observations can be made:

1. Most of the growth in chlorine capacity is occurring in 

Asia, including the subcontinent of India.

2. Sixty-five percent of mercury cell capacity is located in 

Europe.

3. Mercury cells as a percentage of total capacity have 

remained the same or decreased everywhere (only 

exception is northeastern PRC), that is, decommissioning is occurring and most new capacity is not mercury 

cell.

Lindley (1997) reported major improvements in reducing 

mercury emissions from mercury cell processes. However, the 

main emission route is still to air. From 1977 to 1995, the European chlor-alkali industry reported a drop in mercury emissions 

from 220 t to 18 t, a 92 percent decrease.

Legislative Approaches

Netherlands

Maxson and Vonkeman (1996) stated that the Dutch, to 

encourage recycling, have banned the disposal of mercury-containing wastes, and closed the borders to their export since January 1996. Mercury will only be allowed in products whose life 

cycles can be controlled.

The Dutch government has implemented strict measures to 

reduce mercury emissions from industry. The Dutch consider 

10 Although prior analyses were based on 1990 and 1996 data, only 1992 and 1997 

data were available in this case.

that the health risk to the general population of mercury in the air, 

food, and water is now negligible. The aquatic environment is not 

well enough understood to fully appreciate the risks, although it 

is generally agreed that predators (both birds and mammals) that 

feed on fish and (or) other aquatic organisms undergo some risk. 

Mercury is still a problem in Dutch soils, and especially in 

dredged harbor sediments.

Despite the low estimated human risk from mercury, the 

Dutch government has called for reductions in mercury emissions 

to soil, water, and air of 80, 70, and 50 percent, respectively, by 

2000 relative to 1985 emissions. Actual reductions in emissions 

of 40, 70, and 65 percent are expected. The ability to meet the target for water emissions is somewhat uncertain, while the target 

for emissions to soil will clearly be missed, implying that accumulation of mercury in the soil continues. More stringent targets 

will be set for 2010, and additional regulatory measures are under 

consideration.

Sweden and Denmark

Both Sweden and Denmark have already taken steps to ban 

the use of mercury in nonessential applications, as reviewed by 

Maxson and Vonkeman (1996). Furthermore, both countries have 

committed themselves to closing their borders to the transfer of 

mercury-bearing wastes. They have therefore had to address 

questions similar to those being addressed by the Netherlands. 

The key difference is that both Denmark and Sweden have far less 

mercury circulating in the environment than the Netherlands, and 

they do not have such significant secondary sources of mercury. 

Therefore, neither country expects to have to deal with mercury 

surpluses as large as those the Netherlands will have to deal with.

Officially, Sweden considers mercury, as an environmental 

pollutant, to be a global problem requiring an international 

approach. The main strategy for risk reduction in Sweden is to 

phase out all uses of mercury. Formal government legislation with 

*CAGR=Compound Annual Growth Rate. Numbers in parentheses are negative.

Data provided by CMAI through personal communication.

Total

World

North

America

South

America

West

Europe

East

Europe

FSU Africa Middle

East

India

Pakistan

N.E.

Asia

S.E.

Asia

All Cells

1992 45,394

100%

13,575

30%

1,696

4%

11,223

25%

1,896

4%

3,773

8%

535

1%

800

2%

1,523

3%

9,706

21%

667

1%

1997 49,437

100%

14,686

30%

1,787

4%

10,640

22%

1,791

4%

3,676

7%

584

1%

1,294

3%

2,135

4%

11,794

24%

1,050

2%

CAGR 1.72 1.59 1.05 (1.06) (1.13) (0.59) 1.77 10.10 6.99 3.94 9.50

Hg-Cell

1992 12,625

100%

2,016

16%

460

4%

6,984

55%

1,437

11%

248

2%

295

2%

263

2%

898

7%

0

--

5

nil

1997 11,640

100%

1,809

16%

424

4%

6,445

55%

1,174

10%

248

2%

222

2%

276

2%

916

8%

50

nil

5

nil

CAGR* (1.61) (2.14) (1.62) (1.59) (3.94) 0 (5.53) 0.97 0.40 nil 0

% Hg-Cell

1992 28 15 27 62 76 7 55 33 59 0 1

1997 24 15 24 61 66 7 38 21 43 nil nil

Table 2. World chlorine capacity from chlor-alkali plants, in thousands of metric tons.
16 The Materials Flow of Mercury in the Economies of the United States and the World

regard to products was enacted early in 1991. The importation, 

manufacture, and sale in Sweden of the following products were 

prohibited:

• as of 1 January 1992, mercury in glass thermometers;

 • as of 1 January 1993, other mercury-containing thermometers, measuring instruments, and electrical devices 

including level switches, thermostats, relays and circuit 

breakers;

• as of 1 January 1995, mercury-containing pressure 

switches and electrical contacts for the continuous transfer of current.

The most recent Environmental Government Bill (1993/

94:163), which also has the support of Parliament, proposes that 

all remaining products and uses of mercury, with a few exceptions, should be phased out by the year 2000 or sooner. One notable exception is the continued use of mercury in the chlor-alkali 

industry, which is permitted until 2010. 

Early in the evolution of Danish mercury controls, the Danes 

had thought that controlling industrial emissions of mercury 

would be sufficient to reduce human exposure to acceptable levels. It has gradually become clear that this is not sufficient. Products containing mercury are still being produced, and give rise to 

diffuse mercury pollution during use, and to mercury-containing 

waste after disposal.

In general, the official Danish position has now developed to 

the point that exposure of humans to mercury should be kept to an 

absolute minimum. This can be achieved only by minimizing the 

use of mercury for all purposes. The long-term goal of the Danish EPA is to bring all uses of mercury to an end.

Through subsidies promoted by the Danish Government for 

recycling and cleaner technologies, financial support is available 

for research, development, and dissemination of information promoting substitution and recycling of heavy metals. Projects have 

been completed concerning the substitution of mercury in products, as well as improved collection aimed at recycling of specific 

industrial products containing mercury.

One of the key objectives of The Cleaner Technology 

Action Plan 1993–97 is to support the development of environmentally safer products. Concerted efforts are being made by 

industry, research institutions, and others to develop and test, in 

particular, dental filling materials that do not contain mercury. 

An evaluation has been carried out for the possibilities of beginning or improving existing arrangements for the collection, recycling, and (or) proper disposal of used products containing 

mercury, especially electronic equipment and construction/demolition wastes. As part of an ongoing project concerning the recycling of fluorescent light tubes, the possibility of recapturing 

mercury vapor has been investigated, in order to avoid mercury 

emissions and potential occupational health problems.

Japan

Because of several well-publicized industry-related disasters involving pollution by heavy metals, dating as far back as the 

1950’s, the Japanese public and industry are particularly sensitized to such issues (Maxson and Vonkeman, 1996). It is generally 

not considered necessary in Japan to pass legislation aimed at the 

potential hazards of products. Whenever sufficient consensus 

develops that might otherwise lead to legislated restrictions, 

industry “voluntarily” regulates itself to respond to the problem. 

Target restrictions are set by a consensus between government 

and industry, and industry is then free to take the measures it considers most appropriate to meet those restrictions. In the case of 

limit values for pollutants, it is common practice for the Japan 

Environment Agency (JEA) and industry to agree on a provisional value for the first 5 years, which is then reviewed at the end 

of that period.

Norway

Maxson and Vonkeman (1996) commented that the official 

position of Norway is that mercury is one of the heavy metals 

whose effects on the environment and on human health are most 

severe. Risk reduction measures should therefore be based on a 

concern for both health and for the environment. Despite 

decreases in Norwegian discharges, concentrations continue to 

increase in the soil and aquatic systems, leading to restrictions on 

the consumption of certain fish and shellfish.

Brazil

The gold mining situation in Brazil (representative of similar activity in some other developing countries) is important for 

several reasons (Maxson and Vonkeman, 1996). First, Brazil is 

one of the largest present markets for mercury, used extensively 

in the unsophisticated gold mining operations characteristic of 

the interior regions of the country. Second, together with similar 

operations in other developing countries, gold mining is the largest single source of mercury pollution to the environment (especially surface waters) in the world. In the last 20 years, an 

estimated 1,200 t of mercury has been emitted to the Brazilian 

environment due to artisanal gold mining activities! Third, the 

health effects due to this pollution are already visible among 

workers and residents in these areas. Fourth, these mining operations, and the use of mercury, have proven nearly impossible for 

national or regional authorities to control.

Russia, Ukraine, Kyrgyzstan

Following the disintegration of the FSU, substantial stocks 

of mercury came onto the international market, according to 

Maxson and Vonkeman (1996). In desperate need of foreign currency, certain republics offered this mercury at prices as low as 25 

percent of the average world price in 1990, according to The 

Economist in a 1991 report. The European Commission took 

measures to prevent FSU mercury from being “dumped” on the 

European market, but the general effect was nevertheless a 

depression of world prices, which continues to this day.

FSU mines present a curious phenomenon. They are government controlled, but they are likely to be under the influence 

of one or two key individuals. They are not likely to be subsidized, but they are capable of producing mercury at very low cost. 

Finally, they are likely to sell mercury when certain organizations 

or individuals need quick cash, rather than when market prices 

might suggest they should sell. In effect, like state-owned mercury mines in other countries, FSU sales may be little influenced 

by market conditions. However, FSU sales may have significant 

influence on world market prices.
Selected References 17

Conclusions

Environmental concerns, prompted by incidents such as the 

mercury-caused deaths and injuries at Minamata, Japan, have 

produced many rules, regulations, and mandates that, over the 

years, have greatly reduced worldwide mercury production, use, 

and emissions to the environment.

In the United States, there was no mercury mine production 

in 1996, whereas 448 t was produced in 1990. Mercury mine closures, in the early 1990’s, were responsible for a significant reduction of mercury to the environment from the milling and roasting 

of mercury ores. In 1996, secondary production was more than 

four times the level of secondary production in 1990. The change 

from primary mine production to secondary production over the 

6-year period is important because it not only eliminated a major 

source of mercury to the environment, namely 72 t from milling 

and roasting, but it also reflected an increased awareness for recycling. Much of the recycling occurs in States with mercury recycling mandates, and some of it is subsidized. Recycling of 

domestic mercury scrap in 1990 occurred at the rate of 130 t per 

year. In 1996, the rate was 446 t, a 243 percent increase.

Domestic mercury use decreased 48 percent from 1990 to 

1996. In 1996, mercury flowing into all specified industrial uses 

was less than 1990 levels: dental use was down 30 percent, laboratory use down 44 percent, measurement and control devices 

down 62 percent, wiring devices and switches down 30 percent, 

lighting down 66 percent, chlor-alkali down 45 percent, and mercury use in batteries and paints down 100 percent. In 1990, the 

paint industry added mercury to water-based paints, mainly as a 

fungicide. In 1996 this use has disappeared. Mercury-containing 

paints were banned from the market by legislation in 1992. In 

1990, mercury-containing dry cell batteries used 105 t of mercury; in 1996, virtually no mercury went to dry cell batteries.

In 1990, the U.S. government stockpiles released 245 t of 

mercury to the market. In 1996, there were no sales. Sales were 

suspended in 1994 pending the release of the Mercury Study 

Report to Congress (1997b), and have not resumed as of this writing (1999). Mercury imports rose sharply from 15 t in 1990 to 

340 t in 1996. On the other hand, mercury exports decreased dramatically from 311 t in 1990 to 45 t in 1996. This is a total trade 

turnaround of 591 t, indicating a growing dependence on foreign 

supply for the remaining mercury needs of the country.

Mercury emissions to the environment in 1996 decreased 

by 97 t over 1990 levels. Mercury losses from incineration processes decreased by 47 percent between 1990 and 1996. This 

reduction was a function of less mercury-containing products 

entering waste streams as well as stack emission controls on 

incinerators. Mercury disposed in landfills, excluding soil 

amendments, in 1996 was 61 percent less than in 1990.

With regard to the international production and flow of mercury: all producing mercury mines are foreign; 86 percent of the 

mercury cell sector of the worldwide chlor-alkali industry is outside of the United States; there is a large trade (2,037 t in 1990 

and 1,395 t in 1996) in mercury; and environmental regulations 

are not internationally uniform.

The Western European region was the world’s largest mercury supplier in 1996. Spain, the largest producer within this 

area, provided 92 percent of this region’s total output. The FSU, 

principally the nations of Kyrgyzstan, Tajikistan, Russia, and 

Ukraine, was the world’s second largest source of mined mercury 

(785 t in 1996). PRC has widely scattered, but extensive mercury 

reserves and produced 508 t of mercury in 1996. The nation of 

Algeria produced 347 t mercury from its mines in 1996, which 

accounted for all of Africa’s production. Global production of 

mercury in 1996 decreased by 2,019 t over 1990 levels.

Approximately 40 percent of the mercury produced in 1996 

was used in the world’s chlor-alkali industry. Western Europe was, 

by far, the world’s largest reservoir of mercury-cell chlor-alkali 

capacity, and used 631 t mercury in 1996. North America, Eastern 

Europe, and India/Pakistan were also significant users of mercury 

(154, 184, and 133 t respectively) for chlorine production. North 

America, Western Europe, and northeast Asia were the principal 

economies using mercury for the production of mercury-containing goods. Major net mercury exporters, in 1996, included Western Europe, the FSU, and Africa. Major net mercury importers, in 

1996, included Asia, Eastern Europe, and South America.

PRC is the largest consumer of mercury-containing coal and 

the largest importer of mercury in the world. In the future, those 

interested in mercury in the environment will want to know what 

the flows and their associated emissions are in PRC. Although 

estimated mercury use by artisanal gold miners in Brazil 

decreased 50 percent from 1990 to 1996, the impact of the continued use of mercury by artisanal gold miners in countries 

throughout the world is an important international environmental 

concern. Additionally, the consequences of mercury mining and 

production in Tajikistan, Kyrgyzstan, and the Ukraine are of 

interest because of the uncertainty of environmental control 

within the states of the FSU.

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at URL http://www.friends-partners.org/newfriends/edusci/science/

ecostan/ecostan4.6.html.

Center for Mineral Technology (CETEM), 1995, Gold mining (Garimpo) and 

mercury emissions into the atmosphere: Socio-economic evaluation, in Activities report 1995, p. 11–12.

Center for Renewable Energy and Sustainable Technology (CREST), 

Facts about mercury-containing thermostats, accessed May 13, 

1998, at URL http://solstice.crest.org/environment/gotwh/general/

hvac-controls/html/mercury.html.

Chemical Marketing Association, Inc. 1999, (CMAI), Chlorine, world 

capacity tables: Chemical Marketing Association, Inc., 11601 Katy 

Frwy, Number 22, Houston, Tex., 48 p.

Chu, Paul, and Porcella, D.B., 1995, Mercury stack emissions from U.S. 

electric utility power plants, in Porcella, D.B., Huckabee, J.W., and 

Wheatley, B., eds., Mercury as a global pollutant: Water, Air, and 

Soil Pollution, v. 80, p. 134–144.

Cimi–Indianist Missionary Council, 1998, Kayapo children and mercury 

pollution, research by Antonio Barbosa, chemist, university of Brasilia, accessed July 28,1998, at URL http://bioc09.uthscsa.edu/natnet/archive/nl/9410/0267.html.
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Danish Environmental Protection Agency, 1994, Heavy metals: Redegorelse fra Miljostyrelsen, No. 3, p. 27 -31.

Drozdiak, William, 1996, The Rhine River is no longer the “sewer of 

Europe,” accessed August 18, 1998, at URL http://www.seattletimes.com/extra/browse/html/rhin_032896.html.

Farid, L.H., Machaado, J.E.B., and Silva, O.A., 1991, Controle da Emmissao 

e Recuperacao de Mercurio em Rejritos de Garimpo, in Veiga, M.M., 

and Fernandes, F.R.C., eds., Pocone—Um Campo de Estudos do 

Impacto Ambiental do Garimpo: Rio de Janeiro, Brazil, CETEM/

CNPq, p. 27–44.

Gobi International, 1998, The gobi report on mercury, CD ROM: version 2.2.

Harris, R.B., Ask the dentist: The Beacon, Virginia Beach, Va., accessed 

August 20, 1998 at URL http://www.drharris.com/askden.htm.

Heavy Metal Bulletin, 1996, Volume 3, Issue 3, Current amalgam status 

and restrictions world-wide, accessed May 29, 1998 at URL http://

vest.gu.se/~bosse/Mercury/Misc/HMB/amalgamrestrictions.html.

Hedegard, Leif, Amalgam-related illness FAQ, Mercury sources, accessed May 21, 1998, at URL http://hera.algonet.se/~leif/AmFAQk07.html.

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U.S. Bureau of Mines Information Circular 9412, 28 p.

Kenney, C.W., Queneau, P.B., and Hansen, Barry, 1995, State of the art in 

mercury recycling and Remediation of mercury-containing waste, in

International Symposium on the Treatment and Minimization of 

Heavy Metal-Containing Waste, February 12–16, 1995, Las Vegas, 

Nev.: Metallurgical Society of the American Institute of Mining and 

Metallurgical Engineers, 27 p.

Lindley, A.A., 1997, An economic and environmental analysis of the chloralkali productive process—Mercury cells and alternative technologies: Prepared for the European Commission, Directorate-General 

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Water, Air, and Soil Pollution, v. 56, 847 p.

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Mining Journal Ltd., p. 80.

Maxson, P.A., and Vonkeman, G.H., 1996, Mercury stock management in 

the Netherlands, Background document prepared for the workshop, 

Mercury: ban it or bridle it?, 21 November 1996: The Hague, Netherlands, Institute for European Policy, Brussels, Belgium, December, 

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Mercury flow in Sweden, 1997, Swedish mercury consumption and 

deposits in 1996, accessed May 28, 1998, at URL http://vest.gu.se/

~bosse/Mercury/Nature/Swedishflow/flowOne.html.

Mining Journal, 1997, World energy trends, East Europe/CIS slump: Mining Journal, v. 328, no. 8411, January 10, p. 24.

Mishra, C.P., Wilburn, D.R., Hartos, D.G., Sheng-Fogg, C.D., and Bowyer, 

R.C., 1985, Mercury availability—Market economy countries: U.S. 

Bureau of Mines Information Circular 9038, 18 p.

Morgan, C.J., 1995, Porgera pollution: Department of Anthropology & 

Archaeology, James Cook University, Australia, accessed August 18, 

1998, at URL http://listserv.acsu.buffalo.edu/cgi-biwa?A2=ind9512&L 

=anthro-l&F=&S=&P=6490.

National Electrical Manufacturers Association, 1996, The declining 

presence of mercury in batteries and municipal solid waste: 

National Electrical Manufacturers Association, Rosslyn, Va., 22 p.

North Carolina Office of Waste Reduction and Recycling (NCOWRR), 1995, 

Guidance for used fluorescent lamp management, accessed June 16, 

1998, at URL http://www.fac.unc.edu/WasteReduction/fluoresc.htm.

Porcella, Don, Huckabee, John, and Wheatley, Brian, eds., 1995, Mercury 

as a global pollutant: Water, Air, and Soil Pollution, v. 80, 1336 p.

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2.10, p. 18.

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human beings and animals caused by organic mercury contamination, in Hartung, R., and Dinman, B.D., eds., Environmental mercury 

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The Chlorine Institute, Inc., 1998, North American chlor-alkali industry 

plants and production data report—1997: The Chlorine Institute, 

Inc., Pamphlet 10, April 1998, 18 p.

———1998, Report to EPA, May 8, 1998: The Chlorine Institute Inc., 2001 

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Appendix 19

Appendix

Introduction

This Appendix sets forth the methodology for the calculations of mercury flow and stocks represented in figures 2–13. Figures 2, 3, 4, and 11 present a historical perspective on domestic 

mercury sources and use over the period 1970 to 1997. In the 

shorter span between 1990 and 1996, mercury production and use 

changed dramatically. Many changes were mandated by legislation passed because of concerns about mercury and its impact on 

the environment. Figures 5–10, 12, and 13 compare domestic 

mercury flow for 1990 and 1996. Much of the methodology used 

for the study of mercury flows in 1990 has been retained, but several important changes have been made in the development of the 

1996 values. This Appendix explains them in detail. Several elements constrained the development of these data: they had to be 

consistent among themselves; estimates, where possible, had to 

agree with authoritative sources; and some rationale was required 

for estimates where data were not available. In the data tables, column and row data may not add to totals due to independent rounding. The authors welcome suggestions for estimate improvement 

that are based on better data or more pertinent experience.

Perspective Figures

Figure 2, Components of U.S. mercury apparent supply 

(1970–1998), was developed from time series data provided by 

the commodity specialists of the USGS. Domestic apparent supply for each year in the range is shown by a bar having four segments, including net imports, mine production (including byproduct), secondary production from scrap, and U.S. Government stockpile releases. (See footnote 2, p. 3.)

Figure 3, U.S. industrial reported consumption of mercury 

(1970–1997), shows how mercury consumption was distributed 

by sector for the period. Most of the data used to generate figure 

3 were available. However, values for the laboratory sector had to 

be estimated for 2 years (1995, 1996), where an extrapolation 

yielded a rate of decline of 2 t per year that was extended from the 

previous 5 years of data.

Pharmaceutical and agricultural usage was reported for the 

first few years of the period, but not at the end of the series; thus, 

the values, where reported, were added into the “Other” category, 

and no delineation for those categories was made.

The breakout of lighting, wiring devices and switches, and 

batteries did not appear in the series until 1978. Previous to that 

time, only the total was reported. To show these three categories 

from 1970 to 1978, the average of the values for lighting and wiring devices and switches for the years 1978, 1979, and 1980 was 

used for each year from 1970 through 1977, and the values for 

batteries for those years were taken to be the difference between 

the sum of the estimates for lighting and wiring devices and 

switches and the total reported value for the three.

Figure 4, U.S. apparent supply and reported consumption 

(1970 – 98), shows how consumer and producer mercury stock 

changes have been distributed over time. Numbers for most of 

the supply items were available, but net imports of mercury had to 

be estimated for the period 1978 to 1988, during which U.S. 

exports of mercury were not published. To make this estimate, 

we assumed a straight-line appreciation of exports from the value 

of 33 t in 1977 to 221 t in 1989, and subtracted the extrapolated 

values from imports, which were known for this period.

One artifact of the linear growth assumption, especially if 

the growth was really a step function with a long period of low 

export levels, is the failure of apparent supply to close with 

reported consumption, as indicated in figure 4. The reported consumption line lies above the apparent supply line for most of the 

period in question. This could lead to a misinterpretation of the 

period as one of generally decreasing producer/consumer stocks.

Figure 11, U.S. reported consumption, production, price, 

and legislation (1970–1997), juxtaposes discrete legislation passage dates with the time series data for primary mercury production, reported consumption of mercury, and world mercury price 

normalized to 1997 dollars.

Comparative Figures

Figure 5 Versus Figure 6

In the left third of figure 6 are estimated mercury emissions 

to the environment from natural sources, fuel combustion, and 

kiln/smelter activities. To improve the 1996 estimate, the more 

rigorous estimates made by the EPA in its Mercury Study Report 

to Congress (1997b) were used. The EPA’s estimates were for 

1995, and these data have been incorporated into figure 5 as the 

element titled “Emissions from.” Furthermore, the item in figure 

6, “Mercury released from natural emissions,” was not duplicated 

in figure 5 because the update (fig. 5) is targeted towards the 

anthropogenic mercury flow system. “Emissions from” represents actual mercury releases to the environment and excludes a 

large body of mercury that is retained in landfills from previous 

mercury disposal activities. The EPA estimated a loss rate from 

landfills based on effluent gas data, and that small contribution is 

recorded in figure 5.

The middle third of figure 6 and the middle third of figure 5 

are both representations of supply, but different in many important ways. The figure 6 categories “Mercury mine production” 

and its feeders “Milling and roasting” and “Mercury contained in 

ore” were dropped from figure 5 because domestic primary mercury mining has been completely replaced by secondary production from scrap. The concept of estimating mercury contributed/

released to the environment from production activities was 

retained, but the EPA’s estimates are reported. The net result of 

both changes is a rather large decrease (78 to 0.4 t) in mercury 

contribution to the environment from domestic mercury production activities.

The figure 6 item “Mercury recovered from old scrap” and 

the figure 5 item “Secondary production” are identical. Note the 

four-fold increase in supply from this item. State mandates for 

mercury recycling are largely responsible for this major supply 

change. The figure 6 item “Recovered at gold mining operations” corresponds to the update’s “By-product from gold mining.” The original estimate was based on actual survey data. For 

this update, an estimate of 65 t was reported based on the following observations. In 1991 and 1992, although no primary domestic mercury mine production took place, Mineral Commodity 
20 The Materials Flow of Mercury in the Economies of the United States and the World

Summaries (MCS) data were reported for both mercury and gold 

production as shown in table 3.

In 1996, gold production was reported by MCS at 326 t. 

Multiplying by the ratio (0.2), the estimate for mercury is 65 t. 

Kenney and others (1995), using 1994 data, reported that about 

30 gold and silver mining/recovery operations collectively 

recovered about 73 t of by-product mercury using retorts. 

Whether any of this mercury actually was available to the market 

rather than being added to producer stocks was not determined.

The terms “Industry stocks (1/1/90)” and “Industry stocks 

(12/31/90)”, which appear in the middle and right third of figure 

6, have been combined into one item, “Net change consumer 

stocks” (fig. 5). The word “consumer” is used because the MCS 

footnotes this item as “Consumer stocks only.” The convention of 

subtracting start-of-year from end-of-year stocks is used. This 

item could have been presented in the “Sources” column in figure 

5, where the increasing stocks would have been represented by 

negative flows, but we preferred to keep all flows positive. Therefore, an increase in stocks will be a positive flow in the “Destinations” column.

In the middle sector of figure 6, an item labeled “Unaccounted mercury” is reported as withheld (W). In figure 5, a new 

item, “Net change producer stocks,” was created to distinguish it 

from consumer stocks, which are directly reported. The methodology for calculating “Net change producer stocks” is as follows: 

first, the “Destinations” column quantities of “Metal exports” (45 

t), “Net changes consumer stocks” (125 t), and “Industrial usage” 

(372 t), all of which are reported, are totaled (542 t); next, the 

“Sources” column quantities of “Secondary production” (446 t), 

“By-product from gold mining” (65 t), “Metal imports” (340 t), 

“Net change in government stocks” (0 t), and “Net change in mercury cells” (0 t) are totaled (851 t); finally, the reported “Destinations” total of 542 t is subtracted from the “Sources” total of 851 

t and the difference of 309 t is ascribed to “Net change producer 

stocks.” This amount of mercury is an increase in producer 

stocks for 1996. Secondary production has completely replaced 

primary production, and it is uncertain whether either secondary 

producers, or by-product mercury producers, actually sell all of 

their production. Therefore, it seemed reasonable to create the 

producer stock category.

But why would producers increase stocks by an amount 

equivalent to nearly the total of industrial usage? Table 4 shows 

the only mercury imported at full market price to be 33 t from 

Kyrgyzstan. The remaining imports of 307 t, an amount approximately the same as the 309 t attributed to producer stocks, came 

into the United States at less than market price. One conclusion 

is that the producers were willing, in 1996, to buy mercury at 

below market prices and hold it for future sales.

“Released from National Defense & DOE stockpiles” from 

figure 6, and “Net change in government stocks” from figure 5 

are essentially the same in concept, but the new title seemed 

more descriptive of the scenario where the government could 

actually buy mercury (unlikely, but possible), as well as sell it.

A stock in the “Sources” column labeled “Net change in 

mercury cells” was added to figure 5. The mercury cell process 

used in production of chlorine in chlor-alkali plants retains over 

3,000 t of mercury. These types of plants, while viable, have 

been slowly closing. Japan has recycled virtually all of the mercury in its now-closed mercury cells, and for a period of time 

was a large mercury exporter. Although there was no reported 

change in the amount of mercury in domestic mercury cells in 

1996, the potential for change in the future can be accommodated with this new category.

In figure 6, all the outputs go to a box titled “Total U.S. Supply.” This box has been deleted from figure 5, but the total 1996 

flow amount (851 t) is shown prior to being split. This amount 

(851 t) represents mercury metal that will be used for products 

(“Industrial usage”), inventory changes (“Net change producer 

stocks” and “Net change consumer stocks”) and exports (“Metal 

exports”).

Finally, figure 5 shows an arrow representing mercury flow 

from “Industrial usages” going to “Total addition to the environment.” This estimate (13.9 t) was taken directly from the EPA 

Mercury Study Report to Congress (U.S. EPA, 1997b).

Figure 7 versus Figure 8

Generally, figure 7 corresponds to figure 8 in concept. Note 

that mercury embedded in exports and imports of products containing mercury was not included in any of the sectors’ analysis. 

With the exceptions of the wiring devices and switches sector, 

which is known to be considerable and growing, and the electric 

light sector, where imports and exports are approximately equal, 

the remaining sectors’ imports and exports are negligible.

Dental Sector

It was determined that 90 percent of current year mercury 

used for dental applications was used in teeth, 8 percent was 

lost in the dental office in the first year, and 2 percent was lost 

within 10 years (Jasinski, 1994). Furthermore, Harris (1998) 

has reported the average life of a mercury amalgam filling to be 

5–8 years. Seven years was assumed for the calculation. The 

updated estimates for mercury flow through the dental sector are 

illustrated in table 5.

Item 1991 1992

Mercury 58 60

Gold 290 320

Ratio— Mercury:Gold 0.20 0.19

Table 3. Mercury and gold production, 1991–1992, in metric tons.

Origin t Value (1000 $) $/t

Canada 137 791 5,770

Kyrgyzstan 33 266 8,060

Russia 79 302 3,820

Spain 68 327 4,810

Other 23 92 4,000

Total 340 1,778

Table 4. U.S. mercury imports, 1996.
Appendix 21

The amount of mercury added to product stocks in 1996 

was reported as 31 t (fig. 7). The mercury retained in products 

included 7 years’ worth of mercury in teeth (233 t) plus the 

mercury retained in the dental offices, which is eventually lost 

within 10 years. It is assumed that about 1/10 of the 10-year 

mercury total is lost every year. The mercury in Row H represents the 10-year office contribution (3 t) that is retained in this 

sector in 1996. This brings the total 1996 stock to 236 t. The 

mercury leaving the sector includes all of the mercury from 

teeth in the eighth year11 (48 t), the mercury lost from dental 

offices within the first year (2.6 t), and the fraction of mercury 

that dissipates in 1 year from the mercury that is retained in 

dental offices for 10 years, the sum of Row F (0.8 t) for a total 

of 51 t. The 51 t of mercury that exited the dental sector in 1996 

split into 46 t recycled, and by difference, 5 t into dissipative 

(incineration and landfill) loss. This split is based on the 

assumption that 90 percent of mercury generated by the dental 

sector is recycled, mostly as spent fillings that are being 

replaced yearly, or new mercury collected within dental offices 

from amalgam scrap.

Laboratory Sector

Because mercury usage for 1996 was withheld, the estimate 

for 1996 was based on the consistent annual decrease of 2 t 

between 1990 and 1994. Therefore, this sector usage was estimated at 20 t in 1996.

11As a rule, whenever there were no data about the fraction of mercury that each 

year contributes to sector outflow, that is, no recognizable distribution, we 

applied the convention that the next year’s sector usage (the first year 

beyond the average life of the product) was a fair representation of the 

outflow from the sector.

The EPA reported that mercury is used in laboratories in 

instruments, and as reagents and catalysts. Without specific data 

on the distribution of mercury to these three subsectors, we 

assumed that 1/3 of the annual input goes to each subsector. The 

life within each subsector was based on the EPA’s estimate of a 5-

year life for instruments, reagent 1 year, and catalyst 2 years. 

Applying these assumptions allowed us to generate table 6, which 

provides the mercury flows through this sector.

The amount of mercury going into laboratory product 

applications in 1996 is estimated to be 20 t. The mercury 

retained in the laboratory sector includes 5 years’ worth of mercury in instruments (43 t) plus 1 year’s worth of mercury in 

reagents (7 t), plus 2 years’ worth of mercury in catalysts (15 t), 

a total of 65 t. Mercury exiting the laboratory sector in 1996 

includes the sixth year of mercury in instruments (11 t), the 

second year of mercury in reagents (8 t), plus the third year of 

mercury in catalysts (9 t), a total of 28 t. The 28 t of mercury 

NOTE TO READER: To distinguish among the various values expressed in tables 5 though 12 and 14 and their associated text, the authors provided the following formats. For persons with color printers, blue equals mercury inflows to sectors, red equals mercury in inventories (use), and magenta equals mercury outflows from sectors. For persons with noncolor printers, bold text equals blue, italicized text equals red, and underlined text equals magenta.

Table 5. Mercury usage in the dental sector (1986–1996), in metric tons.

Item Action 96 95 94 93 92 91 90 89 88 87 86

A Sector usage 31 32 24 35 42 41 44 39 53 56 52

B Amt. to fillings A*.90 29 22 32 38 37 40 35 48

C '96 flow

from teeth

8th year

48

D Dent. office

loss, 1st yr.

.

A*.08

2.60

E Amt. dent. off. loss > 

10 yrs.

A*.02

0.64 0.48 0.70 0.84 0.82 0.88 0.78 1.10 1.10 1.00

F 10% of 2% 

to '96 outflow

E*.10

0.06 0.05 0.07 0.08 0.08 0.09 0.08 0.11 0.11 0.10

G % Dent. Off. loss 

retained in '96

Multiplier

0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0

H Amt. to dental. sect. 

inventory

G*E

0.58 0.38 0.49 0.50 0.41 0.35 0.23 0.22 0.11 0.00

 Year Usage Instruments

(33.3%)

Reagents

(33.3%)

Catalysts

(33.3%)

1996 W, 20e

1995 W, 22e 7.3 7.3 7.3

1994 24 8.0 8.0 8.0

1993 26 8.7 8.7

1992 28 9.3

1991 30 10.0

1990 32 10.7

e= estimated, 

W = withheld

Table 6. Mercury usage in the laboratory sector (1990–1996), in metric 

tons. 
22 The Materials Flow of Mercury in the Economies of the United States and the World

that leaves the laboratory sector in 1996 splits into a 25 t flow 

into recycling, and, by difference, a 3 t flow into dissipative 

(incineration and landfill) loss (fig. 7). This split is based on the 

assumption that 90 percent of mercury generated by the laboratory sector is recycled, mostly as spent instruments and catalysts.

Measurement/Control Devices Sector

Table 7 contains mercury usage provided by the USGS for 

measurement and control devices for the last 7 years. In 1996, 

41 t of mercury went into product applications. In addition to 

these base data, the EPA reports that the major portion of mercury production in this sector is thermometers, which have an 

estimated average life of 5 years.

The mercury retained in products includes 5 years’ worth of 

mercury used for this sector (331 t). Mercury exiting this sector 

1990 1991 1992 1993 1994 1995 1996

Hg use 108 90 80 65 53 43 41

Table 7. Mercury usage in the measurement and control devices sector 

(1990–1996), in metric tons.

Year Usage

(A)

Accumulation of mercury 

outflow

(B)

Contribution to

1996 outflow

(C)

Contribution to product 

inventory

(D)

1996 49

1995 84 1%, 1 1%, 0.8 99%, 83

1994 79 2%, 2 1%, 0.8 98%, 77

1993 83 3%, 3 1%, 0.8 97%, 80

1992 82 4%, 3 1%, 0.9 96%, 79

1991 71 5%, 4 1%, 0.7 95%, 67

1990 70 6%, 4 1%, 0.7 94%, 66

1989 141 7%, 10 1%, 1.4 93%, 130

1988 176 8%, 14 1%, 1.8 92%, 160

1987 131 9%, 12 1%, 1.3 91%, 119

1986 103 10%, 10 1%, 1.0 90%, 93

1985 95 11%, 11 1%, 1.0 89%, 84

1984 94 12%, 11 1%, 0.9 88%, 83

1983 80 13%, 10 1%, 0.7 87%, 70

1982 69 14%, 10 1%, 0.7 86%, 59

1981 91 15%, 14 1%, 0.9 85%, 77

1980 106 16%, 17 1%, 1.0 84%, 89

1979 111 17%, 19 1%, 1.1 83%, 92

1978 110 18%, 20 1%, 1.1 82%, 90

1977 103* 19%, 20 1%, 1.0 81%, 83

1976 103 20%, 21 1%, 1.0 80%, 82

1975 103 21%, 22 1%, 1.0 79%, 81

1974 103 22%, 23 1%, 1.0 78%, 80

1973 103 23%, 24 1%, 1.0 77%, 79

1972 103 24%, 25 1%, 1.0 76%, 78

1971 103 25%, 26 1%, 1.0 75%, 77

1970 103 26%, 27 1%, 1.0 74%, 76

1969 103 27%, 28 1%, 1.0 73%, 75

1968 103 28%, 29 1%, 1.0 72%, 74

1967 103 29%, 30 1%, 1.0 71%, 73

1965 103 30%, 31 1%, 1.0 70%, 72

1964 103 31%, 32 1%, 1.0 69%, 71

1963 103 32%, 33 1%, 1.0 68%, 70

Table 8. Mercury usage in the wiring devices and switches sector (1963–1996), in metric tons.

* Based on the EPA statement that production was constant at 1 million units, mercury input for the unreported early years was estimated to 

be the average of production from 1978 through 1986, excluding recession years 1982 and 1983.
Appendix 23

in 1996 was 108 t, which was 1990’s mercury use. The 108 t of 

mercury that left the measurement/control devices sector in 1996 

was split in half, 54 t each flowed into recycling and into dissipative (incineration and landfill) loss. The 50 percent assumption, 

based on recycling, is arbitrary, yet seems reasonable given the 

fact that these devices are widely spread throughout society.

Wiring Devices/Switches Sector

Neglecting mercury imports for wiring devices and 

switches, which could be substantial in this sector, the amount of 

mercury going into product applications in 1996 was reported in 

the USGS Minerals Yearbook as 49 t. The EPA’s Mercury Study 

Report to Congress (U.S. EPA, 1997b) noted that electrical 

switches containing mercury were not manufactured prior to the 

1960’s. This study also reported that 10 percent of electrical 

switches were discarded after 10 years, 40 percent after 30 years, 

and 50 percent after 50 years, and that thermostats had approximately a 20-year life. The results of incorporating this information into the estimates are shown in table 8.

The mercury retained in product is the sum of the numbers 

in column D (2,670 t), which was determined by subtracting the 

1 percent per year wasting rate from the reported yearly usage. 

Mercury exiting this sector in 1996 is the sum in column C (32 t) 

that splits into two equally divided streams of 16 t each. Again, 

this split is based on the assumption that 50 percent of mercury 

generated by this sector will be recycled.

Electric Light Sector

The electric light sector includes both fluorescent lamps and 

high-intensity discharge lamps (HID). The EPA reported12 the 

following: the average mercury content of each fluorescent lamp 

unit has decreased from 46 to 23 milligrams over the period 

1990–1995; the 1992 split between fluorescent and HID lamps is 

96:4 (confirmed by Kenney and others (1995), for 1996 production); HID lamps average about 62 milligrams mercury per unit; 

and the average life of both fluorescent and HID lamps is 4 years. 

Table 9 shows the decrease in mercury content, per fluorescent 

lamp, by year.

Table 10 illustrates the methodology for calculating the mercury flow through the electric light sector. Lamp production and 

sales were extracted from Department of Commerce data, and the 

mercury usage from the USGS Minerals Yearbook was based on 

lamp wholesaler survey estimates. Disregarding mercury 

imports and exports13 (equal in 1996) of fluorescent and HID 

lamps, the amount of mercury going into product applications in 

1996 was estimated to be 11 t. The mercury retained in products 

included 4 years’ accumulation of mercury usage for this sector 

(64 t) and the mercury exiting this sector in 1996 equals the total 

mercury usage calculated from 1991 (23 t).

The stream split was based on the lamp-recycling rate 

reported by Kenney and others (1995). They determined that in 

12 Incorporating National Electrical Manufacturer’s Association (NEMA) data. 13 If this sector’s flow analysis is updated in the future, the analyst will want to 

obtain more data on imports. PRC, a major mercury producer, has also 

become one of the world’s largest producers and exporters of electric lamps.

1995, the United States had capacity (24 hour operation, 300 days 

per year) to recycle 60 percent of lamp production. However, 

only about 1/5 of capacity was being utilized. This calculates out 

to approximately 3 t. Therefore, the electric light sector in 1996 

split into a 3 t flow into recycling, and a 20 t flow into dissipative 

(incineration and landfill) loss.

Batteries Sector

Although mercury batteries were no longer being produced 

in 1996, some of the mercury-containing batteries from prior 

years’ production were still in the system. Despite the fact that 

in-service batteries retain their utility for as long as 2 years, Kenney and others (1995) reported that the mean retention time for 

batteries in households was 4 years. The 4-year life estimate was 

used to calculate the mercury in product inventory based on usage 

listed in table 11.

The mercury retained in product includes 4 years’ worth of 

mercury used for this sector (32 t). Mercury exiting this sector 

in 1996 includes the fifth year of sector mercury use (18 t). The 

split into recycling (2 t) and dissipative loss (16 t) is based on the 

assumption that 10 percent of mercury generated by this sector is 

recycled. The 10 percent assumption is arbitrarily based on the 

fact that batteries are widely spread throughout society, and the 

level of adherence to recycling mercury mandates is high, to 

keep these materials out of municipal solid waste.

Chlor-Alkali Sector

Mercury usage in the chlor-alkali industry has decreased 

due to the decreasing proportion of mercury cells making up 

chlorine production capacity and tighter mercury recycling in the 

mercury cell subsector. The mercury flowing through the chloralkali sector is shown in table 12.

The amount of mercury going into this process was 136 t in 

1996. The mercury retained in the process, actually within the 

working mercury cells, is estimated to be 2,770 t. Additionally, 

the industry’s on-site recycling activity contains an inventory of 

134 t, and a make-up inventory of purchased mercury of 150 t. 

The sum of these three inventories represents the industry’s total 

working mercury inventory of 3,050 t. The mercury leaving this 

sector is estimated from EPA TRI data and is discussed in the next 

paragraph.

A figure of 136 t of mercury leaving the sector in 1996 is 

based on the fact that 136 t of mercury was purchased in 1996: 

the system being essentially in equilibrium requires purchases to 

make up for system losses. Toxic Release Inventory data informs 

that 19 t flows into landfills, 7 t flows into off-site recycling, and 

8 t is lost to fugitive and stack emissions. One can estimate, 

based on plant data, that about 1 t leaves the plant associated 

Table 9. Mercury content in a fluorescent lamp (1990–1996), in 

milligrams.

Year 1990 1991 1992 1993 1994 1995 1996

Hg 46 38 34 30 27 23 19

The figures for 1990 and 1995 in the table are reported values, and the remaining 

figures are extrapolated estimates. The assumption is a straight-line decrease in 

mercury content.
24 The Materials Flow of Mercury in the Economies of the United States and the World

with impurities in the caustic product. This leaves 101 t of 

outflows from the chlor-alkali industry as unaccounted. For 

development of figure 7, the only concern was with the mercury 

leaving the system for off-site recycling and for land filling. This 

total is 26 t.

Obsolete Product Disposition Estimates

The “Disposition” column in figure 7 has three categories: 

“Secondary production” to represent recycled material; “Incineration loss” to represent the fraction of mercury that is released to 

the environment from municipal waste combustors (MWC), 

medical waste incinerators (MWI), hazardous waste combustors 

(HWC), cement kilns, and sewage waste combustors; and “Land 

or landfill,” which includes mercury contained in items that are 

applied to land as soil amendment or that are directly landfilled, 

and collected mercury from incineration activities.

The subcategory “Secondary production” is the connection 

between figure 5 and figure 7. The 446 t of mercury from figure 

5 establishes the limit in figure 7 for the sum of recycled materials 

from the industry sectors.

The EPA, in its Mercury Study Report to Congress, estimated mercury incineration losses as follows: 26.9 t from MWC, 

14.6 t from MWI, 6.4 t from HWC, 4.4 t from cement kilns, and 

1 t from sewage sludge incineration, a total of 53.3 t.

The EPA reported mercury collection efficiencies for various control devices as follows: flue gas desulfurization 30.85 

percent; spray dryers 25.59 percent; fabric filters 28.47 percent; 

electrostatic precipitators 23.98 percent. It was assumed that 27 

percent applied overall.

The total mercury going into all types of incinerators 

would be:

Mercuryinput = 53.3/(1–0.27) = 73 t (1)

Approximately 12 percent of generated municipal solid 

waste (MSW) goes into MWC; the remainder is directly landfilled. Correspondingly, about 95 percent of medical waste goes 

into MWI, 95 percent of hazardous waste goes into HWC, or 

cement kilns, and 26 percent of sewage sludge is incinerated, 36 

percent is used as soil amendment, and 38 percent is directly 

landfilled.

The total mercury going into municipal waste combustors 

in 1996 would be:

Mercuryinput to MWC = 26.9/(1–0.27) = 37 t (2)

The total mercury in MSW would be:

MercuryMSW = 37/0.12 = 308 t (3)

The mercury from MSW going to the landfill would be:

MercuryLandfill = 308–37 = 271 t (4)

Table 10. Mercury usage in the electric light sector (1991–1996).

Year Lamp

production

(millions)

Fluorescent

fraction

(96%)

Hg per unit

(milligrams)

Hg usage (t) HID fraction 

(4%)

Hg per unit 

(milligrams)

Hg usage (t) Total Hg

usage

(t)

1996 550 528 19 10 22 62 1.4 11

1995 550 528 23 12 22 62 1.4 13

1994 550 528 27 14 22 62 1.4 15

1993 550 528 30 16 22 62 1.4 17

1992 550 528 34 18 22 62 1.4 19

1991 550 528 42 22 22 62 1.4 23

1991 1992 1993 1994 1995 1996

Hg use 18 13 10 6 3 0

Table 11. Mercury usage in the battery sector (1991–1996), in metric 

tons.

1991 1992 1993 1994 1995 1996

Hg use 184 209 180 135 154 136

Table 12. Mercury usage in the chlor-alkali sector (1991–1996), in 

metric tons.

Other Sector

Table 13 demonstrates how end-use mercury reporting has 

changed over the years, as percent of total usage in the various 

sectors. The following assumptions about the flows through this 

category were made. A product life of 3 years and a 10 percent 

recycling rate for this category were chosen based on assumptions made for prior sectors. The mercury flowing through the 

“Other” sector is shown in table 14.

The amount of mercury going into product inventories in 

1996 is estimated to be 84 t. The mercury retained in product 

includes 3 years’ worth of mercury used for this sector (349 t). 

Mercury exiting this sector in 1996 includes the fourth year of 

sector mercury use (112 t). The 112 t of mercury that leaves the 

sector in 1996 splits into a 11 t flow into recycling (10 percent), 

and, by difference, a 101 t flow into dissipative (incineration and 

landfill) loss.

Unaccounted Sector

The purpose for this category is to make the “Outflows” sum 

to the totals in the “Disposition” column of figure 7. It is an artifact of the methodology used. With regard to “Secondary production,” 64 percent is “Unaccounted.” With regard to “Landfill” and 

“Incineration loss,” 33 percent is “Unaccounted.” Further 

research is suggested to reduce the relative size of the contribution from the “Unaccounted” section.
Appendix 25

The mercury from the MWC going to the landfill would be:

MercuryTo Landfill From MWC = 37 * 0.27 = 10 t (5)

The total mercury from MSW, the amount going directly, 

and the amount from MWC, going to the landfill would be (271 + 

10) = 281 t. Similarly, the total mercury from MW going to the 

landfill is 7 t, the total mercury from HW going to the landfill is 

4 t, and the total mercury from sewage sludge incineration is 1 t. 

The total mercury input to landfills from these sources would be 

295 t (fig. 7).

Some mercury is known to leave the system attached to the 

caustic product, which is mainly used at paper mills. This is about 

1/2 t per year (rounded to 1 t in fig. 9). This leaves 101 t of outflow 

from the chlor-alkali industry as unaccounted; this number is 

incorporated into the 116 t which outflows from the “Unknown” 

sector listed under the “Product/process stocks 1/1/96” in figure 7.

The estimate of the amount of mercury contained, and continuously recycled, through mercury cells in chlor-alkali plants 

was derived as follows: Art Dungen (Chlorine Institute, written 

commun., December 11, 1998), reported that 14 mercury-cell 

plants were operating in the United States in 1996. Within these 

plants, there were a total of 726 working mercury cells. A single 

mercury cell contains between 7,000 and 10,000 pounds of mercury. Given this information, it was assumed that the distribution 

of 7–10 thousand pound mercury cells was normal, such that the 

average of 8,500 pounds mercury per cell applied. The estimate 

for mercury in mercury cells was therefore:

Mercurytotal in Hg-cells = 8,500 lb/cell * 726 cells * 0.90718/2,000 

= 2,800 t (6)

F. Anscombe (EPA, oral commun., December 11, 1999) reported 

that one mercury cell plant of which he had knowledge held 

200,000 pounds of mercury in 24 cells. This calculates to 8,330 

pounds mercury per cell. Using this number to replace the 8,500 

in the calculation above yields a total of 2,740 t. Averaging the 

two estimates gives 2,770 t of mercury residing in mercury cells 

(fig. 9).

From figure 9, 150 t of make-up mercury, 134 t of mercury 

cycling within the recycle loop, and 2,770 t of mercury in cells 

were added to obtain the 3,050 t estimate of total mercury within 

the chlor-alkali segment of the industry.

Category 1970 1980 1996

Agriculture 4 W NR

Amalgamation <<1 NR NR

Catalysts 4 NR NR

Dental preparations <<1 NR 8

Electrical apparatus 23 NR NR

Lights part of electrical 

apparatus

W 8

Wiring Devices/Switches part of electrical 

apparatus

5 13

Batteries part of electrical 

apparatus

38 0

Other electrical part of electrical 

apparatus

W NR

Chlor-Alkali 30 24 37

Laboratory 1 <<1 W

Measurement/Control Devices 4 3 11

Paint 21 22 NR

Pulp/Paper <<1 NR NR

Pharmaceuticals <<1 NR NR

Other 11 7 23

Table 13. Reported mercury end-use categories (1970, 1980, 1996), in percent. 

[<<, much less than; W, withheld; NR, not reported]

Table 14. Mercury usage in the “Other “sector (1992–1996), in metric 

tons.

1992 1993 1994 1995 1996

Hg use 112 121 135 93 84

Figure 9 Versus Figure 10

In 1996, the industry purchased 136 t of mercury to service 

a make-up mercury inventory, estimated from the average of 3 

years (1995, 1996, and 1997) of annual purchases to be about 

150 t. In addition to the make-up inventory, the industry retains 

about 134 t of mercury in its on-site recycling activities and 

about 2,770 t in the mercury cells themselves. The sum of these 

three inventories represents the industry’s total working mercury 

inventory of 3,050 t, as shown in figure 7.

The mercury leaving the industry is estimated from EPA 

Toxic Release Inventory data as follows: 19 t flow into landfills, 

7 t flow into off-site recycling, and 8 t lost to fugitive and stack 

emissions. 
26 The Materials Flow of Mercury in the Economies of the United States and the World

Figure 10 shows flows in 1990. The chlor-alkali industry 

purchased 247 t of mercury to service a make-up mercury 

inventory, estimated from the average of 5 years (1988, 1989, 

1990, 1991, and 1992) of annual purchases to be about 275 t. In 

addition to the make-up inventory, the industry retained about 

153 t of mercury in its on-site recycling activities, and about 

3,170 t in the mercury cells themselves. These estimates were 

made by taking the ratio of chlorine capacity for 1990 and 1996. 

The sum of these three inventories represents the industry’s total 

working mercury inventory of 3,600 t in 1990.

The mercury leaving the industry in 1990 is estimated from 

EPA Toxic Release Inventory data as 60 t flow into landfills, no 

flow into off-site recycling, and 9 t lost to fugitive and stack 

emissions.

Some mercury is known to leave the system attached to the 

caustic product, which is mainly used at paper mills. This is about 

1/2 t per year (rounded to 1 t in fig. 10). This leaves 177 t of outflow from the chlor-alkali industry as unaccounted in 1990.

Figure 12 and Figure 13

Table 15 contains the data for the production, use, and flow 

of mercury on a global basis and underlies the presentation in 

figures 12 and 13.

For table 15, the listed “Regions” include the following 

countries: North America—Canada, Mexico, and United States; 

South America—Central and South America; West Europe—Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, 

Luxembourg, Norway, Portugal, Spain, Sweden, Switzerland, and 

United Kingdom; East Europe—Albania, Bulgaria, Czech 

Republic, Bosnia-Herzegovina, Federal Republic of Yugoslavia, 

Hungary, Macedonia, Poland, Romania, Slovakia, and Slovenia; 

FSU—Kyrgyzstan, Tajikistan, Russia, and Ukraine; Middle 

East—Iran, Iraq, Israel, Jordan, Saudi Arabia, Turkey, and United 

Arab Emirates; Africa—Algeria, Egypt, Gabon, Libya, Morocco, 

South Africa, and Tunisia; India and Pakistan; Northeast Asia—

PRC, Japan, Korea, and Taiwan; Southeast Asia—Australia, Indonesia, Singapore, and Thailand.

Production

“Production” was taken from the Gobi Report (Gobi, 1998). 

Some discrepancies exist between the Gobi production data and 

the USGS data for the years in question. For example, total global mercury production for 1990 was 4,100 t according to USGS 

sources, and 5,356 t according to Gobi. Likewise, USGS 

reported total mercury production in 1996 as 2,795 t, versus 

3,337 t by Gobi. As the Gobi Report provided the most complete 

set of trade flows, and considering that flow patterns were more 

important than flow precision, the Gobi production data were 

used for this part of the analysis.

Uses

This part of table 15 delineates four mercury uses: chloralkali production in mercury cells; manufactured products that 

Table 15. Global mercury production, use, and flow 1990 and 1996, in metric tons. 

[n.a., not available]

Region Production Use Net flow

Chlor-alkali Manufactures Artisanal gold Stock changes

1990 1996 1990 1996 1990 1996 1990 1996 1990 1996 1990 1996

North

America 1,297 526 319

 

154 553

 

238 n.a. n.a.

 

 255 84 -170

 

-50

South

America 0 5 72

 

62 65

 

 20 200 100 34 18 +371 +195

West

Europe 882 1,141 1,067

 

631 440

 

 177 n.a. n.a.

 

-1,165 -30 -540 -363

East

Europe 163 25 209

 

184

 

88

 

28 n.a. n.a. 30 21 +164 +208

FSU 1,400 785 34 34 150 60 n.a. n.a. 459 9 -757 -682

Middle

East 47 0 101

 

81 35

 

18 n.a. n.a. 7 5 

 

+96 +104

Africa 637 347 43 36 1 9 unknown unknown 3 2 -570 -300

India and

Pakistan 0 0 138

 

133 66

 

30 n.a. n.a. 20 16 +224 +179

NE. Asia 930 508 0 5 375 445 unknown unknown 1,688 701 +1,133 +643

SE. Asia 0 0 20 24 25 36 unknown unknown 4 6 +49 +66

World

Total 5,356 3,337 2,003

 

1,344 1,818

 

1,061 200+ 100+ 1,335 832

 

 0 0
Appendix 27

contain mercury; artisanal gold mining; and stock changes. 

These parameters were estimated as shown.

Chlor-Alkali Production

Chemical Marketing Association Inc. (CMAI, 1999) provided a complete global listing of chlor-alkali plant capacity, broken out by production method, which allowed the isolation of 

each country’s mercury-cell chlorine capacity. Country estimates 

for mercury usage in chlor-alkali production were calculated by 

multiplying the mercury-cell chlorine capacity by the U.S. ratios 

as follows: (annual mercury purchases for mercury cells) / (mercury cell capacity). 

The above ratio was different for 1990 and 1996, 0.1444 versus 0.0918 t mercury per thousand metric tons mercury cell chlorine capacity, respectively. The decrease in mercury usage rate 

was attributable to increased efficiencies in the operation of mercury-cell chlor-alkali plants in the United States, and tightened 

controls on system mercury losses, both of which are indicated by 

reduced purchases of mercury.

We assumed that some of the developing countries had not 

accomplished the same increased mercury-cell efficiencies and 

loss controls as had the United States. Therefore, the 1990 ratio 

(less efficient than 1996 ratio and requiring higher use for same 

capacity) was utilized to estimate 1996 mercury use for those 

countries.

Manufactures (Products Containing Mercury)

Except for the United States, very little international sector 

(dental, instruments, lighting, and others) information was available. A reasonable estimate was feasible for the chlor-alkali 

industry from the existing data, but was not possible for other 

sectors. We decided to estimate the total amount of mercury that 

would likely be going into manufactured products for each country. The following assumptions were made: each country has a 

level of economic sophistication proportional to that of the 

United States; total chlorine production capacity (chlorine production being ubiquitous throughout the world) for each country 

is a good indicator of economic sophistication; and supporting 

data must be available for each country. Accordingly, annual 

ratios for the years 1990 and 1996 were calculated as follows: 

(U.S. mercury purchases for mercury-containing products) / 

(total U.S. chlorine production capacity).

Again, this ratio basis was different for 1990 and 1996, 

0.0401 versus 0.0165 t mercury per thousand metric tons total 

chlorine capacity, respectively. The decrease in mercury usage 

rate was attributed to legislation that mandated reductions in mercury use in products, technological advances in lighting leading 

to reduced mercury use in that sector, and tightened controls on 

system mercury losses through recycling.

Following the same line of reasoning as in the previous 

chlor-alkali calculations, the assumption was made that developing countries had not passed the same mercury-conscious legislation as had the United States. For such countries, the 1990 ratio 

was applied to 1996 total chlorine production capacities for the 

purpose of estimating 1996 mercury use for the manufacture of 

mercury-containing products. Specifically, only Western Europe, 

Japan, and Australia were considered to be progressing economically, technologically, and legislatively along the same track as 

the United States.

Anecdotal Information

The data in the “Manufactures” column, table 15, were not 

broken into individual sectors. The following information provides additional insights as to the state of each of these sectors.

Dentistry

Domestically, the use of mercury in dental applications has 

remained almost constant since 1980. Recently, concerns about 

the use of mercury-silver amalgams in women either pregnant or 

contemplating pregnancy has arisen because of evidence that the 

fetus preferentially takes mercury from the mother’s body. The 

use of mercury in dental amalgams (50 percent) is being seriously debated worldwide. As reported by Heavy Metal Bulletin 

(1996), the replacement of amalgam (with ceramics) has been 

suggested in Sweden, Finland, Denmark, and Norway. Canada, 

Germany, Austria, and Sweden have recommended legally nonbinding restrictions for mercury amalgams. Japanese dentists 

are directly responsible for the safe disposal of mercury. Amalgam separators are legal requirements in Sweden, Norway, Germany, and Switzerland. In Denmark, mercury-containing 

product sales have been banned since 1994, with the exception of 

amalgam. Germany and Austria have laws to outlaw amalgam 

by the year 2000.

Batteries

Mercury-oxide batteries have been banned from commercial 

use in the United States and Europe. Demand for this product has 

been eliminated entirely in these areas. Although PRC has legislation on the books that will eliminate mercury-oxide battery production by the year 2002, the question of how many are being 

produced currently is unanswered. Whatever the number, the use 

is restricted to developing countries because such products cannot be exported to the United States or Europe. The substitutes 

for mercury-oxide batteries all contain traces of mercury, and battery-recycling programs have developed worldwide.

Button batteries, primarily “button type” containing mercury, 

are still produced by Gold Peak (Hong Kong) and other companies. They are not used in consumer devices in United States. 

However, the Ever Ready amplifier battery, EP-675, may still be 

manufactured by the Ever Ready Company for use (overseas) in 

hearing aids.

Fungicides

Fungicides containing mercury are no longer produced in 

developed countries. Mercury-containing fungicides were previously added to latex paints. Agriculturally, mercury-containing 

fungicides were used to control brown mold in freshly sawn 

lumber and to combat Dutch elm disease and snow mold. Some 

golf courses still use mercury-containing fungicides. As with 

batteries, these uses have been controlled or prohibited by law in 
28 The Materials Flow of Mercury in the Economies of the United States and the World

developed countries. Again, no reliable information exists about 

production and use in developing countries, although there have 

been reports (Iraq) of local poisonings from grains treated with 

mercury-containing fungicides.

Fluorescent Lamps 

Fluorescent lamps contain about 200 parts per million mercury. From 1985 to 1995 the mercury content of fluorescent 

lamps has decreased by 35 percent (NCOWRR, 1995). PRC is a 

major producer of fluorescent lamps; however, few data are available on Chinese lamp production, use, disposition, and trade. 

Chinese fluorescent lamps could conceivably be a vehicle for 

mercury flow into the United States.

Laboratory Chemicals

Mercury used in laboratories in many cases finds its way 

into the municipal water treatment plant, where it goes straight 

through into receiving waters. With regard to the international 

use and disposal of laboratory chemicals, no data are available.

Electronic Equipment 

Electronic equipment such as thermostats and electrical 

switches can contain significant amounts of mercury. With regard 

to the international use and disposal of electrical equipment, no 

data are available.

The Danish Environmental Protection Agency (1994) 

reported that from 1977 to 1990, mercury use declined from 31 t 

to about 11.5 t (63 percent), closely tracking the U.S. experience. 

Although it is not reported in this way in other European countries, one may infer from European Union environmental legislation and the quality of annual mercury flow monitoring reports 

that Europe is reducing mercury use through product bans. 

Whether this is occurring in developing countries to the same 

degree is an open question.

Artisanal Gold

One of the greatest environmental concerns is associated 

with artisan gold mining in the Amazon basin. The Center for 

Mineral Technology (CETEM, 1995), Brazil, estimated that 140 

t of mercury were being used every year by artisanal gold miners 

in the Amazon region. In 1990, 50 percent of reported gold production was from artisanal miners. In 1996, only 20 percent of 

reported gold production was by artisanal gold miners. In table 

15, the artisanal gold miner’s use of 200 t mercury in 1990 and 

that of 100 t mercury in 1996 were extrapolated from the CETEM 

estimate and reported artisanal gold production.

Stock Changes

The parameter “Stock changes” is an artifact established to 

balance production, use, and flow (net imports). Information 

regarding stock changes on a country-by-country basis was limited. Any information available was used, and flow was estimated 

or adjusted. In some cases, it was estimated for a subject country 

as either 5 or 10 percent (based on economic sophistication) of 

the sum of estimated mercury use for chlor-alkali and manufactures for that particular country.

Net Flows

“Net flows” was extracted directly from trade flow data contained in the Gobi Report. Net flow data were not available for all 

countries. For countries where net flow data were unavailable, an 

estimate was made to balance production and use. The assumption was made that global net flow summed to zero.