Coastal Pollution: Effects on Living Resources and Humans - Chapter 2 doc

27

2

Minamata Disease

The “Dancing Cat Disease” of Minamata

Sometime in the early 1950s, weird behavior began to be noticed in some of
the nonhuman inhabitants of small fishing towns near the industrial city of
Minamata, on the island of Kyushu in southern Japan. Birds tumbled from trees,
or flew erratically, occasionally bumping into houses in their flight. Cats walked
with a peculiar lopsided gait, or ran in tight circles, eventually becoming totally
disoriented and dying. Locals called the condition “dancing cat disease.” Not
long after these strange happenings were first observed, abnormalities began to
occur in humans as well — abnormalities of increasingly frightening proportions.
Fishermen and members of their families began to experience neurological
disabilities: tremors, numbness of face and limbs, paralysis, visual disturbances
(especially constricted vision), mental disorientation, and speech disorders.
Advanced cases lost control of body functions, became bedridden, and died.
Mortality was about 40% of affected individuals. The full horror of the disease
was still ahead — in the birth of blind, dreadfully deformed, and mentally
impaired children (Smith and Smith 1975). The affliction was first called “the
strange disease” and later “Minamata Disease.” By the end of 1956, 52 victims
had been identified in the small fishing communities surrounding Minamata Bay.
The search for a cause was painfully slow, and was impeded by govern-
ment/industry foot-dragging and denials by both parties that a problem existed.
Mercury contamination of Minamata Bay and its fish and shellfish populations
by the effluents of a chemical production company was suspected as the cause,
and was reported as such in the scientific literature in 1959. It was not until

1968, however, that the Japanese government stated officially that organic
mercury contamination of fish and shellfish was the cause of the disease in
human consumers, and that the chemical company (a part of the Chisso Cor-
poration) was the source. Later investigations disclosed that during the period
1932 to 1965 Chisso had dumped 80 tons of organic mercury into the bay. The
company denied legal responsibility until 1973, although beginning in 1959 it
had begun offering poisoning victims and their families minuscule compensa-
tions (so-called “solatiums,” which acknowledged corporate concerns but were
not to be considered admissions of guilt). For all the suffering, disfigurement,
and death that this company had caused, it paid “solatiums” of only $800 for
a death, $280 per year for adult victims, and $83 per year for afflicted children!
(These amounts were increased in the 1970s after public outrage and legal
decisions in civil suits forced action by Chisso.) Present compensation consists
of a lump sum payment of about 24 million yen (about 240,000 U.S. dollars).

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Coastal Pollution: Effects on Living Resources and Humans

By 1975, 793 victims had been designated officially, but about 2700 other
people living in the polluted zone around Minamata City had symptoms of mercury
poisoning, and an additional 10,000 residents were considered latent victims.
[According to the most recent government information (March 1997), 2762 victims
have been certified in the Minamata area, although many other cases are still being
contested in courts, or have gone unobserved, or have been concealed because of
family pride
, during the long interval from the early 1950s to the present.]

But the Japanese mercury poisoning story was not confined to Minamata.
In 1964, another outbreak of the “strange disease” due to mercury poisoning
was discovered on the west coast of Japan, near the city of Niigata. The source
of contamination was traced to a factory of the Showa Denko Corporation that
was using the same acetaldehyde pr
oduction process (with a mercury sulfate
catalyst) as that used by Chisso in Minamata — with mercury being dumped
into adjacent river waters. Cases were mostly confined to fishermen and their
families, for whom fish was a dietary staple. Fortunately, the scale of contam-
ination was less than that of Minamata Bay
, with fewer deaths and disabilities.
T
o the present time, 690 cases of Minamata Disease have been certified officially
from the Niigata area.
Then in 1973, a third outbreak of the disease, involving only 10 cases, was
reported from the coastal area bordering the Ariake Sea, 40 km north of
Minamata Bay. Announcement of that outbreak touched off near-panic in all of
Japan, accompanied by short-term but widespread incidents of civil disorder,
aimed at for
cing reduction of pollution by large industries and increasing
government regulatory activities at prefectural and national levels.

F
rom Field Notes of a Pollution Watcher

(C.J. Sindermann, 1983)

CHRONOLOGY OF EVENTS RELATED TO
MINAMATA DISEASE

The Minamata mercury poisoning episode has become an important milestone in
global environmental thinking, and, because components of such events become
obscured with the passage of time, it seems useful here to summarize principal
events on a time scale. It also seems relevant to consider those events from several
perspectives: those of the victims, the scientific community, and the polluting indus-
tries and the regulatory agencies.
All the elements of high drama are here: the human pain and suffering, the
struggles by scientists for understanding, the uncaring polluting industry, the reluc-
tant governmental regulatory bodies, and the endless legal maneuvering to assign
guilt and to secure adequate compensation for victims. Each group has its own
perspective on the happenings. To minimize confusion, a time and event summary
for each of the principal entities involved follows, with their perspectives on the
unfolding story of Minamata disease in Japan.

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Minamata Disease

29

P

ERSPECTIVE



OF

THE

V

ICTIMS

Early 1950s

— Fishermen and their families began exhibiting signs of an unknown
illness characterized by trembling, numbness of hands and feet, paralysis, and loss
of control over body functions. It was first thought to be an infectious disease, and
signs of the affliction resulted in social ostracism of the victims. The Chisso factory
was a known polluter of the bay, but it was also essential to the economy of the
region, so when the disease became associated with eating contaminated fish, the
local business community and the local government refused to confront the com-
pany directly.

1958

— Disease victims and their families formed a mutual assistance society
to negotiate with Chisso for compensation but were rebuffed (Huddle et al. 1975).

1959

— With the publication of a university scientific report implicating Chisso
in polluting the bay, the demands of the fishermen’s union for compensation for
reduced catches became more violent. Repeated demonstrations were held at the
factory. A mediation committee formed of local politicians proposed a minimum
solatium that specifically ignored the matter of compensation to disease victims.

More than 2000 fishermen rioted, stormed the factory gates, and caused extensive
damage. The riots brought national attention; disease victims conducted a sit-in,
demanding that medical compensation be included in any settlement. An agreement
was reached at year’s end, even though the victims’ mutual assistance society was
extremely unhappy with the ridiculously small amounts of the solatiums ($800 for
a death, $280/yr for adult victims, $83/yr for children, and $56 for funeral
expenses). The fishermen’s union was the principal negotiator of the agreement
(Huddle et al. 1975).

1960–1967

— The insultingly small solatiums to victims paid by Chisso sub-
dued protests for a number of years, even though the victims continued to live in
poverty and many received no treatment. Late in 1964, a second outbreak of
Minamata disease occurred in the area of the Agano River near the city of Niigata.
The sequence of events followed the course of the original outbreak in Minamata:
illness and death among poor people with a fish diet, denial of responsibility by
the polluting company, suppression of academic research findings by government
agencies, and demonstrations and legal actions by victims’ associations. By 1967,
victims from Niigata were cooperating with those from Minamata with joint protests
and legal claims.

1968

— The national government finally and belatedly agreed that organic
mercury caused Minamata disease and that its source in the Minamata area was the
Chisso factory, and in the Niigata area the Showa Denko factory. It also passed in
December 1968 the Pollution Victims Relief Law (later called the Pollution-Related
Health Damage Compensation Law), in which certified victims of mercury poison-
ing received a lump sum payment. Chisso claimed inability to pay the compensa-

tions, so the national government has “assisted” (National Institute for Minamata
Disease 1997).

1973

— A prefectural court found Chisso guilty of gross negligence, and the
company finally admitted its responsibility for creating conditions leading to organic
mercury poisoning — a clear victory for Minamata victims. Chisso also agreed to

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Coastal Pollution: Effects on Living Resources and Humans

pay compensation of 16 to 18 million yen (US$51,000 to US$59,000) to victims,
but by 1975 Chisso was already requesting government loans.

1992

— In addition to compensation to certified victims, the Japanese govern-
ment began providing financial or medical support to residents of contaminated
areas, to reduce health-related anxieties.

2000

— Almost 3000 victims of organic mercury poisoning have been certified
for compensation under the terms of the
Victims Relief Law. Victims are now eligible

for lump sum payments of about 24 million yen (roughly US$240,000 at the present
rate of exchange). Chisso has claimed inability to pay the cost, so the national
government has “assisted” with its payments.

2001

— The Japanese Supreme Court awarded an additional total sum of US$2.8
million to 51 plaintif
fs who claim illness from mercury poisoning.
The drama is not over. Every year, 400 to 700 people apply for certification and
compensation — individuals who did not apply in the past, for various reasons, or
those who were rejected earlier.

A S

CIENTIFIC

P

ERSPECTIVE

1956

— The “strange disease” was first officially described by the director of
Minamata’s Chisso Hospital as “severe damage to the central nervous system of
humans.” In that same year, a scientific/medical group (including Kumamoto Uni-
versity researchers) was designated by the prefectural government to search for the
cause. The first report of that group suggested very tentatively that the cause might
be “heavy metal intoxication from eating contaminated fish.”

1957

— The university group reproduced the disease signs seen in cats by
feeding experimental animals fish caught in Minamata Bay. The group recommended
a ban on fishing in the bay, but no action resulted. Local fishermen were urged to
limit fishing in the bay, but no compensation was provided.

1958

— After many inconclusive tests of various pollutants, organic mercury
became a prime suspect, principally because a British neurologist, D. McAlpine,
visited Minamata for 2 days and subsequently published a paper in

The Lancet

(September 20, 1958) suggesting that concentration of organic mercury in nerve
tissue could produce the symptoms seen in Minamata patients.

1959

— Despite delays imposed by the Kumamoto Prefecture government, a
university research report was published concluding that the causative agent of
Minamata disease was organic mercury. The report identified Chisso effluents as
“the likely source” of organic mercury compounds found in the environment (Huddle
et al. 1975). Minamata thus became the first recorded episode of mass mercury
intoxication from

indirect

transmission from a contaminated coastal environment.

1960–1967

— Charges by Chisso scientists resulted in the termination in 1960
of research grants to Kumamoto University scientists studying Minamata disease.
Grant support was assumed for 3 yr by the U.S. National Institutes of Health (NIH).
Organic mercury was found in the factory effluents in 1962, and it was found to
be concentrated as it moved up estuarine food chains. The chemistry of conversion
of inorganic mercury used as a catalyst for acetaldehyde production to methyl-
mercury was also described in 1962. The prefectural and national governments,

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Minamata Disease

31

particularly the National Ministry of Health and Welfare, repeatedly suppressed or
delayed scientific reports on Minamata disease. This was in part a result of some-
times obstructive cooperation between government ministries and industry (Huddle
et al. 1975).

1973

— The national government of Japan announced that during 33 yr of
acetaldehyde production at Minamata (1932–1965), Chisso had discharged an esti-
mated 80 tons of methylmercury into the bay.

1978

— The National Institute for Minamata Disease was established to carry
out medical studies of the disease and to conduct medical examinations of
possible victims.

1996

— The institute’s role was expanded to include international chemical and
environmental studies of mercury poisoning in humans.

1997

— Monitoring of methylmercury concentrations in fish and shellfish con-
tinued in the Minamata area, as did other investigations that led to the conclusion
that “continuous methyl mercury exposure at the level which can cause Minamata
Disease existed until no later than 1968 in the Minamata area and after that there
has not been such exposure” (National Institute for Minamata Disease 1997).

2001

— Medical scientists disagree about the validity of neurological tests used
to identify and certify victims of Minamata disease.

I

NDUSTRY

/R

EGULATORY

P

ERSPECTIVE

Before 1950

— The huge Chisso Corporation, located on the shore of Minamata
Bay in southern Japan and established in 1908, became a major producer of polyvinyl
chloride, acetaldehyde, and other synthetic chemicals used in plastics manufacturing.
Increased production for a booming economy, without concern for environmental
consequences, was the prevailing philosophy of the time, and this philosophy was
reflected in very tolerant government regulatory attitudes toward the actions of large
polluting industries like Chisso.

1950

— Because of conspicuous postwar pollution damage to the fisheries, the
local fishermen’s union appealed to Chisso for compensation. The company, citing
lack of scientific evidence, denied responsibility for any deterioration of the bay.

1953

— The first cases of what came to be called the “strange disease” were
reported to local authorities in Minamata City.

1954

— Chisso purchased land and fishing rights from the fishermen’s union to
compensate for past and future damages, with the provision that “even if further

damages occurred, no new claims would be made.” The company promised to test
its effluents, install treatment equipment, and carry out pollution control measures
(none of these steps was implemented, and fish production continued to decrease).

1959

— A Kumamoto University report identified organic mercury as the cause
of the “strange disease” (which became known as “Minamata disease”). The report
implied that Chisso was the source of the mercury, and its publication caused
intensified efforts by fishermen and victims to receive compensation, as well as
efforts by the company to deny responsibility and to discredit the organic mercury
theory. Also in 1959, a scientist employed by Chisso reported to company manage-
ment his experimental results with cats, finding that the factory effluents produced

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Coastal Pollution: Effects on Living Resources and Humans

signs of the condition then known as “dancing cat disease.” Chisso suppressed the
report until 1968, and the experiments were terminated (Ui 1968).

1968

— The Japanese government stated officially that organic mercury com-
pounds in industrial effluents caused Minamata disease.

1970

— The Water Pollution Control Act was enacted to reduce or eliminate
industrial mercury and cadmium discharges in all of Japan.

1973

— Chisso admitted its responsibility for the mercury pollution and agreed
to pay compensation to present and future victims. It also agreed to cooperate with
the government in the cleanup of the bay.

1975

— Chisso applied for a government loan of US$33 million, in an attempt
to shift responsibility for compensation payments, and began spinning off its more
profitable subsidiaries as independent companies.

1976

— Kumamoto Prefecture began removing 1.5

×

10

6

m

3

of contaminated
bottom sediments from Minamata Bay. Chisso was to pay 60% of the costs of
removal. Work was completed in 1990.

1977

— Nets that had been installed in 1959 to reduce movement of fish into
or out of Minamata Bay were removed, with the assumption that the methylmercury
problem had been resolved.

1997

— Testing for methylmercury contamination in fish continued, as did other
investigations by the National Institute for Minamata Disease.

2001

— Government and industry appealed the Japanese Supreme Court award
of US$2.8 million to Minamata disease victims.
Table 2.1 is a further condensation of events from the perspectives of victims,
scientific, and industry/regulatory bodies.

WHAT HAS BEEN LEARNED FROM THE
MINAMATA EXPERIENCE?

The sheer horror and accompanying public outrage over the Minamata poisonings
marked an important turning point in national and eventually international attitudes
about industrial development and environmental abuse. The phenomenal economic
growth of Japan after World War II was accomplished at a huge cost in environmental
degradation and human suffering. Minamata continues as a stark illustration of that

reality, and one that the Japanese people recognized and began changing in the 1970s.
Events during the course of massive and culpable polluting episodes like this
one seem to follow an almost predictable course. The polluting industry, deliberately
or through negligence, dumps toxic wastes into rivers or estuaries. Fish and shellfish
may be affected, in that abnormalities appear and populations may decline. Fish-eat-
ing birds and mammals (including humans) may be affected by ingested toxic
chemicals, so that sickness and death may result. Medical scientists address the
problem after growing public concern results in release of research funds. Investi-
gations focus on suspect chemicals, and evidence accumulates about a specific
contaminant and its likely source.
During this period of initial uncertainty, the polluting company vehemently denies
that its effluents can maim or kill, even when it has evidence from studies by its own

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Minamata Disease

33

TABLE 2.1
Important Milestones in the History of Minamata Disease

Victims Science Industry/Government

Fishermen of Minamata
encounter reduced catches and
blame pollution from Chisso
factory, beginning in 1926
Fishermen’s union appeals to

Chisso for compensation for
lost catches in 1926, 1943, and
1950
Chisso denies responsibility for
reduced fish catches, 1950
First cases of “strange disease”
reported during early 1950s
A university scientific/medical
group is designated by the
prefectural government to
search for the cause of the
“strange disease,” 1956
Chisso factory management
refuses to allow scientists
access to its effluents, 1956
Disease victims form mutual
assistance society to negotiate
with Chisso, 1958
First report of the scientific
investigation of the “strange
disease” suggests heavy metal
intoxication as a cause, 1956
After demonstrations and riots
outside Chisso factory, an
agreement was reached at the
end of 1959 in which the
company paid tiny “solatiums”
to disease victims and small
compensations to the
fishermen’s union

The first scientific report
implicating organic mercury as
the probable cause of
Minamata disease was
published in 1959
Chisso begins paying
“solatiums” but continues to
deny responsibility, 1959
The U.S. National Institutes of
Health provided principal
financial support to Kumamoto
University research on
Minamata disease, 1960–1963
A second outbreak of Minamata
disease occurred at Niigata,
near the Showa Denko factory
in 1964
Niigata University designated by
the Japanese government to do
research on Minamata disease,
1964

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Coastal Pollution: Effects on Living Resources and Humans

First report of Niigata research

scientists points to mercury
pollution from the Showa
Denko factory as the cause of
the disease outbreak, 1966
Victims from Minamata joined
with those from Niigata in legal
actions for compensation in
1967
Production of acetaldehyde by
Chisso discontinued at
Minamata in 1968
National government passes
pollution-related Health
Damage Compensation Law,
providing compensation to
victims, 1968
Japanese government states
officially that Minamata
disease was caused by organic
mercury from the Chisso
factory, 1968
National Water Pollution
Control Law enacted, 1970
Chisso agrees to pay victims
compensation of US$51,000 to
US$59,000, 1973
Chisso requests loan of US$33
million from national
government to help pay
victims’ compensation costs,

1975
Kumamoto Prefecture begins
dredging 1.5

×

10

6

m

3

of
contaminated bottom sediment
from Minamata Bay, 1976
Nets preventing fish from
moving into or out of
Minamata Bay removed, with
the assumption that the
mercury problem had been
eliminated, 1977
National Institute for Minamata
Disease established, 1978
National government begins
providing financial and
medical support to residents of
contaminated areas, 1992

TABLE 2.1 (Continued)
Important Milestones in the History of Minamata Disease

Victims Science Industry/Government

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Minamata Disease

35

capti
ve scientists that the company’s effluents are responsible (as did the Chisso
management early in the Minamata incident). Scientists in the employ of the polluting
industry conduct their own investigations, but they never release their findings (except
to the CEO and the board of directors). Governments and their regulatory agencies,
during this phase of denial, are reluctant to act against the industry in the absence of
truly o
verwhelming data and vigorous public outcry against the polluters. Civil suits
instituted by individuals or groups may eventually resolve the impasse, if decided in
favor of the victims, and if endless appeals by the polluting industry are denied. The
proffered settlements are invariably far too small to compensate for damages; the
polluter then pleads poverty and begs for a government bailout. The final stage is
threatened or actual declaration of bankruptc
y, after the company has spun off the
more profitable of its subsidiaries as independent companies.
The sequence of events in these major pollution episodes, often dragging on
over several decades, seems to follow this common pattern — almost a formula —
augmented occasionally by new legal devices designed to avoid admission of respon-

sibility for en
vironmental degradation or damage to resources and people. One of
the few positive aspects of this prolonged struggle of victims against polluting
industries has been the reinforcement of an important legal concept that had been
developed during repeated earlier confrontations with polluters of Japanese waters,
which states: “In the absence of conflicting clinical or pathological evidence,

epi-
demiolo
gical

proof of causation [of human disease] suf
fices as

le
gal

proof of cau-
sation.” This hard-won concept — which has become known as the “Minamata
Principle” — will be important in any future major contamination episode, anywhere
in the world, that results in human illness.
Today there is widespread recognition in Japan of the reality that post–World
War II industrial development succeeded at a large cost in environmental damage

Role of National Institute for
Minamata Disease expanded to
include environmental and
international studies, 1996
Lump sum payments
underwritten by the Japanese

government are specified at 24
million yen (US$240,000),
1997
Japanese Supreme Court awards
an additional total sum of
US$2.8 million to 51 plaintiffs
who claim illness from
mercury poisoning, 2001
Medical scientists disagree
about the validity of
neurological tests used to
identify and certify Minamata
disease, 2001
Industry/government appeal
Supreme Court award of
US$2.8 million to Minamata
disease victims, 2001

TABLE 2.1 (Continued)
Important Milestones in the History of Minamata Disease

Victims Science Industry/Government

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Coastal Pollution: Effects on Living Resources and Humans

and in damage to human health. Environmental protection has received increasing
attention there since the late 1960s, when the consequences of earlier polluting
practices began to be identified. Pollution prevention and control policies have been
implemented throughout the country and in adjacent waters.
The Minamata experience, partly because of widespread media coverage and
public demonstrations, was an important factor in developing awareness of a
national pollution problem and in g
aining support for preventive and remedial
actions (Ui 1968).

REFERENCES

Huddle, M., N. Reich, and N. Stiskin. 1975.

Island of Dreams: Environmental Crisis in Japan.

Autumn Press, New York. 225 pp.
National Institute for Minamata Disease. 1997. Our intensive efforts to overcome the tragic
history of Minamata Disease. Spec. Rep., NIMD. 23 pp. (In English)
Smith, W.E. and A.M. Smith. 1975.

Minamata.

Holt, Rinehart and Winston, New York. 220 pp.
Ui, J. 1968.

The Politics of Pollution.

Sanseido, Tokyo. (In Japanese)

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