Minamata disease ismethylmercurypoisoning that leads to neurological symptoms.The condition develops after a person has been eating heavily contaminated seafood daily.
This article will go over what Minamata disease is, the history of how it developed, and what the effects are today.
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The Minamata Disaster
The story of the poisonings starts in several small fishing villages on the edge of Minamata, Japan, on the coast of Minamata Bay. Given the location, the people living here ate a lot of seafood.
In the mid-1950s, the villagers started to notice their cats were behaving strangely—specifically, falling into the sea. Some people even believed the cats' behavior was an act of suicide.
Soon after, villagers started to report unusual symptoms like:
Like the cats, some people began acting strangely. Something was affecting theirnervous system—but what could it be? The fish-based diets of the villagers and cats seemed to be the common thread, leading scientists to suspect that the fish in Minamata Bay were being poisoned.
Chisso denied the allegations and continued manufacturing without changing production practices. Chisso continued to deny that its mercury waste was causing any illnesses. It was later estimated that Chisso Corporation had dumped 82 tons of mercury compounds into Minamata Bay.
As the mercury dumping continued over time, pregnant people were poisoned, leading to the birth of babies with congenital Minamata disease. The children were born with severe deformities, including motor dysfunctions such as spasticity and coordination difficulties, mental deficits, deafness, and blindness.
The fishermen of Minamata began protesting Chisso Corporation in 1959, demanding that the company stop dumping toxic waste and compensate the villagers for the methylmercury poisoning linked to it.
Recovering From Minamata Disease
Chisso finally stopped poisoning Minamata’s waters in 1968. In the early 1980s, groups of plaintiffs filed lawsuits against the Japanese government and the Chisso Corporation, alleging that the government had failed to regulate Chisso’s pollution activities adequately and had neglected to protect the environment and public health despite clear violations of pollution laws.
Is Minamata Disease Still Around?Yes, residents in Minamata City and the surrounding areas are still dealing with the medical effects of Minamata disease. According to the Japanese Ministry of the Environment, as of 2013, almost 3,000 people had been certified as Minamata patients. By this time, more than 2,300 had died.Some researchers believe this number is too low with reports that “tens of thousands” of people in the area have neurological symptoms consistent with methylmercury poisoning.
Is Minamata Disease Still Around?
Yes, residents in Minamata City and the surrounding areas are still dealing with the medical effects of Minamata disease. According to the Japanese Ministry of the Environment, as of 2013, almost 3,000 people had been certified as Minamata patients. By this time, more than 2,300 had died.Some researchers believe this number is too low with reports that “tens of thousands” of people in the area have neurological symptoms consistent with methylmercury poisoning.
Yes, residents in Minamata City and the surrounding areas are still dealing with the medical effects of Minamata disease. According to the Japanese Ministry of the Environment, as of 2013, almost 3,000 people had been certified as Minamata patients. By this time, more than 2,300 had died.
Some researchers believe this number is too low with reports that “tens of thousands” of people in the area have neurological symptoms consistent with methylmercury poisoning.
On October 15, 2004, the Supreme Court of Japan ordered the government to pay 71.5 million yen ($703,000) in damages to the Minamata disease victims, holding the government liable for negligence in regulating industrial pollution that contributed to the outbreak.The Environment Minister bowed in apology to the plaintiffs. After 22 years, the plaintiffs achieved their goal of making the people responsible for Japan’s worst case of industrial pollution pay for their negligence.
More than 65,000 people applied for this compensation, showing that over five decades later, the effects of the disaster arestill being felt.
Summary
When people (and cats) in the village consumed fish and shellfish from the contaminated water, they ingested high levels of methylmercury, leading to serious neurological illnesses.
After decades of legal battles, the victims of the Minamata disaster were compensated. When people (and cats) in the village consumed fish and shellfish from the contaminated water, they ingested high levels of methylmercury, leading to serious neurological illnesses.
Frequently Asked Questions
The organic form of the metal mercury, known as methylmercury, causes Minamata disease.
Notable symptoms of mercury poisoning, particularly from organic mercury (methylmercury), include headache, tremors,insomnia, memory loss, muscle weakness, and cognitive and motor dysfunction.The severity of symptoms depends on the type of mercury, the amount and duration of exposure, a person’s age, and whether mercury was ingested, inhaled, or absorbed through the skin.Learn MoreMercury Poisoning: What You Should Know
Notable symptoms of mercury poisoning, particularly from organic mercury (methylmercury), include headache, tremors,insomnia, memory loss, muscle weakness, and cognitive and motor dysfunction.The severity of symptoms depends on the type of mercury, the amount and duration of exposure, a person’s age, and whether mercury was ingested, inhaled, or absorbed through the skin.
Notable symptoms of mercury poisoning, particularly from organic mercury (methylmercury), include headache, tremors,insomnia, memory loss, muscle weakness, and cognitive and motor dysfunction.
The severity of symptoms depends on the type of mercury, the amount and duration of exposure, a person’s age, and whether mercury was ingested, inhaled, or absorbed through the skin.
Learn MoreMercury Poisoning: What You Should Know
Additionally, be careful when using products that contain metallic mercury. Certain thermostats, fever thermometers, and even novelty jewelry can pose the risk of mercury exposure if their contents are released.
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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World Health Organization.Mercury and health.
U.S. Food and Drug Administration.Advice about eating fish.
Environmental Protection Agency.How people are exposed to mercury.
The Japan Times.Mercury pact falls short on Minamata.
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