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(this is not an essay. It's a story...)

Why did Minamata pollution prove so destructive?

In 1953, inhabitants of Minamata, a city on the South-western coast of Kyushu, began to fall ill with a mysterious degenerative disease that attacked the central nervous system, leaving patients with impaired mobility, speech, and hearing, and which often led to death. In time, the cause was revealed - methyl mercury that had been discharged into Minamata Bay by a local factory run by Chisso Corporation Ltd. This then entered the food chain through fish and shellfish, which were consumed in large quantities by local fishing families, resulting in their affliction with what became known as Minamata Disease (Smith and Smith, 1975; George, 2001).

Despite the fact that thousands were affected, this lethal discharge of organic mercury compound continued until 1968, 16 years after the problem was first brought to light. The reasons were to be found in the hold that Chisso Corporation had over the people of the ‘company’ town, its close links with local government and its powerful place in the national government’s program of petrochemical industry-led economic growth. Indeed its cessation was due only to the company’s decision to end production of Acetaldehyde (of which organic mercury was a by-product) rather than in response to outside pressure (Ishimure, 1972; George, 2001).

Inevitably, what could have been a relatively minor environmental incident, had it been dealt with effectively at the outset, took on epic proportions, with hundreds of thousands exposed to the pollution. Many of these people still suffer today. Over 30 court cases have been fought, and, as of September 2005, compensation payments totalling 134 billion yen have been made to victims by Chisso and the Japanese Government (Kinjō et al., 1991; Ninomiya et al., 1995; George, 2001; Kerr, 2001; Sakamoto et al., 2001, 267; Kyodo, 2006).

The impact upon those who were unfortunate enough to contract the disease before the cause was discovered was devastating. Cruelly, it was traditional fishing families, that is, those on the margins of the newly-industrialised society, those who could least afford medical bills, and who could least afford to lose valuable workers to a debilitating disease, who suffered the most. One such family was that of 28-year-old Yamanaka, a fisherwoman who, until the onset of Minamata Disease in mid-July 1956, had enjoyed perfect health. The first sign of her illness was a numbness in her fingers – this was followed two days later by a deterioration in her hearing. Shortly after this she began to find difficulty in walking, and in early August was admitted to the local isolation hospital. Within two weeks she had fallen into a state of severe delirium, in which she would howl like a dog, suffer convulsions, and then rigidity. Her condition rapidly deteriorated, until by 4am on the 3rd of September, just 52 days after the onset of the illness, she was dead (Kumamoto Medical Society, 1957, cited in Ishimure, 1972, 38-39).

There were thousands more who eventually contracted the disease, enduring varying degrees of the illness which ate away at healthy brain cells causing irreparable damage (Takeuchi et al., 1961).

The destructive power of Minamata pollution was keenly felt not only by those who were unfortunate to come down with the disease, but by the entire fishing industry that bounded the semi-enclosed Shiranui Sea of which Minamata Bay is a part. With Chisso’s adoption of a new manufacturing process in August 1951 (ironically devised by a technician who not only served as a wartime Plant Manager, but also became a four-term mayor of Minamata) the level of mercury pumped into the harbour had increased dramatically, thus causing a rapid deterioration of the quality of water and associated fish stocks (Ishimure, 1972; George, 2001). The fishermen, who had fought the company for years over the issue of pollution, found themselves swamped by debt as they borrowed more and more money to buy increasing amounts of bait – all to no avail. By 1958 the average catch had fallen to less than 1% of that of only 5 years previously. By 1961, the number of families engaged in fishery had almost halved from that of the pre-outbreak years (Ishimure, 1972; George, 2001, 72-73).

When news of the disease spread, the fishermen, many of whom were now developing the disease themselves, were dealt a further blow as consumers (fearful of contracting the strange illness) refused to buy their catches, despite assurances by the fishing co-operatives that they were not from the affected area. The government did absolutely nothing to remedy the situation. Even though there was a clear risk to public health, a fishing ban was never introduced, as this would not only have been an admission that there was a serious pollution problem, but would have resulted in a legal duty being placed upon them to compensate the fishermen for lost income.

Meanwhile, the pollution was causing devastating damage to the wider community, as a gulf opened up between the victims and the townspeople, the majority of whom saw any attack upon the company as an attack upon the city itself. Chisso did indeed provide a lifeline to the rural town at the time; not only did it account for 48% of the city’s tax receipts in 1960, but also 19.2% of employment. With a former Plant Manager in the mayoral office for much of the 1950s and 1960s, Chisso had a great deal of influence over local and prefectural politics, and frequently used its power to sway public opinion in its favour whenever it came under fire. When, in 1959, local fishermen broke into the factory compound and rioted, the non-fishing locals responded not by looking at the crimes committed by the company that led to this outburst of pent-up frustration, but rather, joined forces with the factory workers and voiced condemnation of the action and vowed to fight those who had ‘victimised’ their company (Ishimure, 1972, 125; George, 2001). The strength of these sentiments did not wane: as late as 1970, by which time the patients had finally succeeded in bringing the case to court, locals were publishing pamphlets with titles such as “Patients, What Do You Think Will Be Left in Minamata If You Ruin the Company”, in which they warned “No matter who supports you, no matter what your reasons, the citizens of Minamata will rise up as one to thwart your attempts to destroy Chisso” (cited in George, 2001, 226). Another local resident, in an interview with the Asahi newspaper declared that “The Weirdo patients have inflated their story out of all proportion and instigated the press and public opinion against Chisso. The company will surely go bankrupt, and the whole town with it. It’s us who risk losing everything, not those damned, drooling idiots!” (cited in Ishimure, 1972, 343).

The hostility shown towards the victims of Minamata Disease marked an end to the traditional support networks that had existed in the town. The local council, by insisting on disinfecting patient’s homes with DDT and confining them to the isolation ward when hospitalised made the situation far worse by promoting the false rumour that the disease was contagious, a belief that lives on even today (Ishimure, 1972, 226; Kyodo, 2006). Many patients found the stigma attached to their condition (which was partly due to the natural Japanese attitude of shame and fear in connection with physical or mental health problems), and the prejudice that they experienced as a result of it too much to bear, and chose to conceal their illness from others. The hostility of the townsfolk towards those seeking compensation from Chisso was such that many patients were unwilling to apply for certification; thus the pain caused to sufferers was needlessly prolonged as they were unable to receive recognition for their plight or appropriate medical attention (Upham, 1993, George, 2001).

Even doctors were treated with suspicion and distrust. When it became evident that no cure was available, patients began to feel as if they were merely research subjects. Likewise with the press, who throughout the 1950s and 1960s did little in terms of investigative journalism. Rather, they would visit the “poor, backward fishing villages”, ask irrelevant questions, and then turn to either Chisso or the government (which was keen to keep the true cause of the problem hidden) and government or company-financed Tokyo-based professors for the ‘facts’ behind the case, in a bid to remain ‘neutral’ (Ishimure, 1972, 234-235; George, 2001).

One of the major reasons for the prolonging (and therefore worsening) of the Minamata problem was the direct involvement of both the local and national governments in hindering all attempts at identifying the cause, and even when this had been established, delaying the implementation of any remedial action. One of the first warnings of what was to come was given in 1952, when an investigator from Kumamoto Prefecture stated that it appeared that waste from the Chisso plant was causing the decline in fish catches, and recommended that the waste be analysed. However, no action was taken. Again, in May 1956, having reported to the prefectural authorities that the cause of the ‘strange disease’ seemed to be sea water, the head of the prefectural health department was warned by the prefectural governor not to go there again. The Mayor of Minamata was particularly active in the fight against the investigation, in April 1957 telling the Ministry of Health and Welfare that pesticides were the cause – a theory of his own that was without foundation. Other ideas that continued to be pushed by both Chisso and the government (even when discredited by local scientists) included pollution from discarded wartime ammunition and stagnant well-water (Ishimure, 1972, 229; George, 2001, 53-55).

However, in 1959 Chisso found themselves in possession of strong evidence that methyl mercury was the cause, when Professor Hosokawa carried out the famous ‘Cat #400 Experiment’. Since the very beginning of the outbreak ‘dancing cats’ had been a frequent sight, and were indeed one of the causes of the initial media attention. Having consumed mercury-laced fish, cats soon began to lose their senses, fall into convulsions and eventually kill themselves by running into the sea (Takeuchi et al, 1961; Ishimure 1972; van Wolferen, 1989, 55). By feeding Cat #400 with factory waste, he found that it rapidly developed Minamata Disease. On reporting this to the factory manager, he was ordered to immediately cease all experimentation, and sworn to secrecy (George, 2001, 60).

Meanwhile, the Ministry of Health and Welfare issued a warning to other ministries that the disease was most likely caused by the consumption of fish contaminated by Chisso waste. However, under pressure from the company, the prefectural governor and the Ministry of International Trade and Industry (MITI), the report was suppressed. The following year Kumamoto University professors submitted the findings of their own investigation which reached the same conclusion; following this their funding was cut off, and a campaign to discredit the mercury theory swung into action, with Chisso publishing a series of pamphlets to discredit the research. The company stated that without corroborating evidence from their own research team they would not accept the findings. In later years Chisso went even further by employing Sokaiya, security companies with ties to the Japanese mafia, to use physical violence to prevent Minamata patients from asking awkward questions in shareholder’s meetings (the patients having bought single shares to enable them to do just that) (Upham, 1993, 340-341; Kerr, 2001, 56-57; Kaplan and Dubro, 2003, 165-167).

MITI also played an active role in this action by publishing their own pamphlet rebutting the mercury theory, utilising arguments based on skewed data. It was not until September 1968, 9 years following this report, that the Ministry of Health and Welfare finally declared that Chisso were to blame (Ishimure, 1972; George, 2001, 62). In order to determine the reason for this criminal inaction that resulted in a large increase in the number of patients, it is necessary to look at Chisso’s place in the national plan for Japan’s economic recovery, which gained pace following the passing of the Comprehensive Law for the Development of the National Land in 1950 (McCormack, 2001, 44).

Chisso had been targeted by MITI as an essential component in its plan to create a huge petrochemicals industry, and as such, it was essential that the company’s profitability be protected in order to finance a new plant. Because of this, it was vital that the Minamata pollution be prevented from becoming a major issue, and thus, every attempt was made to stall any efforts to disrupt the highly profitable production of Acetaldehyde. In the era of high growth, Tokyo bureaucrats took it as a necessary given that some people on the fringes of society would suffer as a result of Japan’s economic expansion program. This pattern was repeated elsewhere in Japan, with Minamata becoming one of what became know as the Big Four Pollution Cases that came to symbolise the sacrificing of human rights upon the alter of high growth (Upham, 1993, George, 2001).

Ultimately, the strong influence of Japan’s capitalist expansion program which filtered down from the ministries in Tokyo, through the local government to the chemical plant in Minamata, resulted in the patients (who occupied a low socioeconomic stratum) being unable to assert their human rights. The hold that the factory had over the company town robbed them of traditional support networks, whilst it wasn’t until the late 1960s that the media aroused concern for environmental issues - meanwhile leaving the victims completely isolated. It was not just the health of the thousands of disease victims that suffered: the ecosystem of the entire Shiranui Sea was degraded, livelihoods were destroyed, communities shattered, and faith in the new ‘democracy’ put under severe strain.

The Minamata patients ultimately won their case in court and received a government apology. However, 50 years on from the date that the disease was officially recognised, there remain many open wounds. The damage caused by Minamata Disease will undoubtedly take generations to heal.


George, Timothy S. (2001), Minamata: Pollution and the Struggle for Democracy in Postwar Japan, Cambridge, Massachusetts: Harvard University Asia Center.

Ishimure, Michiko (1972), Kugai Jōdo: Waga Minamata-byō, translated by Monnet, Livia (1990), Paradise in the Sea of Sorrow: Our Minamata Disease, Tokyo: Yamaguchi Publishing House.

Kaplan, David and Dubro, Alec (2003), Yakuza: Japan’s Criminal Underworld, Berkeley: University of California Press.

Kerr, Alex (2001), Dogs and Demons: The Fall of Modern Japan, London: Penguin Books Limited.

Kinjō, Y., Higashi H., Nakano, A., Sakamoto, M., Sakai, R. (1993), “Profile of Subjective Complaints and Activities of daily Living among Current patients with Minamata Disease after 3 Decades”, Environmental Research 63: 241-251.

Kyodo (2006), Struggle in Minamata still continues prior to 50th anniversary, Tokyo: Kyodo News Agency. Available from <
storyid=230192> (Updated 15/02/2006, Accessed 13/04/2006 22:54).

McCormack, Gavin (2001), The Emptiness of Japanese Affluence, London: M.E. Sharpe, Inc.

Ninomiya, T., Ohmori, H., Hashimoto, K., Tsuruta, K., Ekino, S. (1995), “Expansion of Methylmercury Poisoning outside of Minamata: An Epidemiological Study on Chronic Methylmercury Poisoning outside of Minamata”, Environmental Research 70: 47-50.

Sakamoto, M., Nakano, A., Akagi, H. (2001), “Declining Minamata male birth ration associated with increased male fetal death due to heavy methylmercury pollution”, Environmental Research 87(2): 92-98.

Smith, Eugene and Smith, Aileen (1975), Minamata, New York: Alskog-Sensorium.

Takeuchi, T., Morikawa, N., Matsumoto, H., Shiraishi, Y. (1961), A Pathological Study of Minamata Disease in Japan, Kumamoto: Kumamoto University School of Medicine.
Upham, Frank (1993), “Unplaced Persons and Movements for Place”, 325-346, in Andrew Gordon (ed.), Postwar Japan as History, Berkeley: University of California Press.

Wolferan, Karel van (1989), The Enigma of Japanese Power, London: MacMillan London Limited.


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