Mercury Treaty Puts Spotlight On Japan's Minamata Chemical Disaster

Oct 9, 2013

Representatives from 140 countries gather in Minamata, Japan, this week to sign a global agreement to reduce mercury in the environment.

This comes nearly 80 years after a chemical plant in Minamata began releasing methyl mercury into the ocean.

The resulting mercury poisoning affected some 60,000 people and was officially recognized as Minamata disease in 1956.

The chemical poisoning is described as one of the world’s worse environmental disasters.

The company and government response to the incident, and the effects on the residents and the environment continue to reverberate today.

Timothy S. George, a professor of history at the University of Rhode Island, joins Here & Now’s Robin Young to discuss the history of the environmental danger and what this new agreement will mean for the company that released the chemicals into the ocean.


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It's HERE AND NOW. Representatives from some 140 countries are in Japan today to finalize an agreement to reduce mercury pollution, mercury pollution known to cause birth defects and brain damage. The treaty calls on governments to cut down mercury from coal-fired power plants and industrial facilities, to phase down the use of mercury dental fillings, to close mercury mines.

The Minamata Convention on Mercury is a sober tribute to the site of one of the worst environmental disasters in history. In 1932, the Chisso Chemical Plant in Minamata, Japan, began releasing methyl mercury into the ocean. Residents began noticing symptoms of poisoning. Minamata disease was officially recognized in 1956, and those effects continue today.

As Japan deals with another environmental disaster at the Fukushima nuclear plant, what have they learned from Minamata? Timothy George is professor of history at the University of Rhode Island. He joins us from Rhode Island Public Radio. And Tim, what happened at the Chisso Plant?

TIMOTHY GEORGE: In Minamata in 1908, a chemical factory was built by the company that later came to be called Chisso, and in 1932 they started making a chemical called acetaldehyde, which is used with other chemicals to make plastics. And they were using mercury as a catalyst in that process, and the organic mercury was dumped directly into the ocean.

Over time that was accumulated and concentrated in the food chain and then consumed by everyone and everything that ate fish and shellfish.

YOUNG: And when did residents realize they were having these health problems?

GEORGE: Well, there were some hints early on, but it didn't become plainly obvious until the early- to mid-1950s, when fishing families noticed that their cats were going crazy; gyrating, dancing and sometimes jumping into the sea. So one of the early names for this unknown disease was the dancing cat disease.

It was first officially reported in 1956 by the best doctor at the best hospital in town, which happened to be the factory hospital, when a couple of young girls were brought to him with symptoms.

YOUNG: Well, and in humans the symptoms were difficulty walking, talking, eating, convulsions because mercury poisoning does what?

GEORGE: It attacks the central nervous system, nerves throughout the body and the brain itself.

YOUNG: So now there's evidence that something is wrong. How did the company and ultimately the government respond?

GEORGE: Well, the symptoms and the disease were reported by this Dr. Hosokawa to the public health office, and a research group was set up based at the prefectural university. The company of course denied any responsibility, but within the company there were secret experiments carried out by that same Dr. Hosokawa who had first reported the disease.

He among other things fed factory waste to cats, and in the fall of 1959, his famous Cat Number 400 died of symptoms of the strange disease. He autopsied it and confirmed that the disease was caused by the factory waste.

When he reported that to his superiors, he was ordered to stop his experiments and keep quiet.

YOUNG: Well, and moving forward in the story, the CEO of the company famously drank water saying it was fine, but it wasn't actually the water that might have been contaminated. Then what happened? I mean, is there a point in the story where the government acknowledged that there should have been more control of this company?

GEORGE: Well, that took some time. You have to remember that the Chisso Corporation had really been at the leading edge of Japan's industrial development in the pre-war period. Its reputation was something like Sony and Honda in the post-war period. And even in the post-war it was considered absolutely essential to Japan's high growth policies.

And so the Ministry of International Trade and Industry blocked researchers from getting access to company waste and company information and pushed the company to build pollution control equipment. They put in something called the cyclator, which was basically a sedimentation system.

It did not remove dissolved mercury from the waste, but it was the water that came out of the cyclator that the president company drank at the end of 1959. The other thing that was done at the end of 1959 was that the company made a so-called salatium agreement with patients in which the patients got sympathy money in return for promising never to sue, even if it was determined in the future that the factory was the cause, and of course the factory knew from those secret experiments that it was.

YOUNG: Well, and we understand people are still filing lawsuits today to get compensation. Was there ever a marker, was there ever a point at which the government fully acknowledge and Chisso fully acknowledged that there was a problem?

GEORGE: Yes, the government in 1968 officially announced that the cause of the disease was the methyl mercury from the Chisso factory. The company itself never officially acknowledged responsibility until it lost, in 1973, a lawsuit brought by patients that ordered it to pay the largest settlement in Japanese legal history up to that time.

YOUNG: And we know some people are still filing to receive compensation. Why is it hard to identify who is deserving?

GEORGE: Well, I think the basic problem all along has been that that became much more than a medical question, it became a political and a financial question because when someone is certified as a victim of Minamata disease, they get a one-time payment from the company, and then the company gives them regular payments to cover their medical costs.

And there was a lot of worry that the company itself would go bankrupt, that it would look bad, that the government would look bad, that if the company went bankrupt the government would have to step in and pay compensation, and that would violate the so-called polluter pays principle, by which the government wants companies to pay the costs of the pollution they cause.

YOUNG: Well, so we hear the story of Minamata, and another legacy is that countries are now gathering to sign a treaty to reduce mercury in the environment. What's to be learned, and what maybe hasn't been learned, from Minamata, when you think of the Fukushima nuclear accident, Fukushima owned by the company TEPCO?

GEORGE: Well, I think we can see answers to that in the debates over naming this convention on mercury after Minamata. The Japanese government wanted to do that partly to show that Japan had learned from the incident and could be a model for cleaning up for the rest of the world.

People in Minamata were divided over that. Some felt that they weren't ready to say the government had learned the lessons because there were so many people who thought they were victims who weren't yet certified.

Certainly it's true that Japan cleaned up its environment very quickly in some ways, from the early '70s on, at least for air pollution, but other things continued unabated, and of course one of those was this rush to use nuclear power.

Now that radiation has been leaking for two and a half years, people wonder how much has really been learned from Minamata. They still wonder if they can trust the government when they find more and more things that weren't told to them earlier.

YOUNG: That's Tim George, a professor of history at the University of Rhode Island, also the author of "Minamata: Pollution and the Struggle for Democracy in Postwar Japan." Thank you so much, Tim, for reminding us of the Minamata story.

GEORGE: Thank you, Robin.

YOUNG: And a quick moment to say tomorrow on HERE AND NOW, the streets of Washington are getting crowded. Furloughed workers and marches for immigration reform. We'll check in on that topic that's been overlooked during the shutdown. But the latest news is next, HERE AND NOW. Transcript provided by NPR, Copyright NPR.