Minamata disease is a neurological condition brought on by severe mercury poisoning. In the technical sense of the word, Minamata disease is not truly a disease; rather, it is a neurological syndrome brought on by environmental and industrial pollution. This indicates that the central nervous system is impacted by pollutant poisoning. Methylmercury is the specific pollutant that causes this condition. Ataxia, numbness in the hands and feet, generalized muscle weakness, loss of peripheral vision, and damage to hearing and speech are some of the signs and symptoms. In severe cases, coma, death, paralysis, and insanity all occur within a few weeks of the commencement of symptoms. Cerebral palsy may result from a congenital type of illness that can also harm fetuses in the womb. This article will explain to you about Minamata Disease which will be helpful in preparing the Environment Syllabus for the UPSC Civil Service exam.

Mercury Pollution

• Mercury is a heavy metal that is present naturally in the air, soil, and water.
• Mercury is one of the top ten chemicals that the World Health Organization (WHO) lists as being of significant public health concern.
• Exposure to mercury can be poisonous and have negative effects on one's health even in minute doses.
• Mercury has an impact on the immune, neurological, and digestive systems.
• Additionally, it harms the kidneys, lungs, eyes, skin, and other organs.
• The brain damage suffered by victims cannot be repaired, and they may experience memory loss or language difficulty.
• Since even small levels of elemental mercury can have negative consequences on health, there is no established safe exposure level for people.
• The most susceptible groups to the negative effects of mercury include children, newborns, and foetuses.
• Because mercury is easily transmitted around the planet by the environment, its harmful effects can be felt even in remote areas.

Minamata Disease - History

• In 1956, the disease was identified for the first time in Minamata.
• The first Minamata Disease patient was described as having neurological symptoms with no known cause.
• Minamata City immediately established the Committee on Unknown Disease upon the report of the first patient in order to take action against the patients and conduct an investigation to determine the cause.
• However, it took a long time before the cause could be determined because at the time, knowledge and experience about environmental pollution were lacking, and equipment for analysing very minute amounts of chemical substances was inadequate.
• Cats and local wildlife were first affected by the illness, which spread to more people over the course of the next ten years as nothing was done to stop the pollution.

Minamata Disease - Causes

• Methylmercury enters the body through a variety of environmental sources, especially seafood, and causes Minamata sickness.
• Hair samples are used to measure the amount of mercury in the body, and it is generally accepted that when these levels are more than 50ppm (parts per million), nerve damage is likely to occur.
• People living in the Minamata area had levels as high as 700ppm, compared to an average level of 4ppm for people living outside.
• Although environmental degradation and contamination caused by mercury poisoning is the primary factor, there are additional reasons as well:
• Biomagnification in Aquatic Food Chain: As was the case for residents of Minamata, the most typical source is through contaminated seafood.
• Methyl mercury was among the pollutants in the waste that was deposited, and it accumulated in the food chain.
• Plankton, the main food supply for aquatic animals like fish and shellfish, absorbed and consumed it.
• The poisoning continue spreading up the food chain as larger fish that ate such tainted fish also ingested the mercury.
• Both fish-eating birds and other predators that preyed on them were contaminated.
• Because individuals in Minamata Bay derived their protein from fish, the risk was increased because the contaminants were not spread over a large region but rather stayed concentrated within the bay.
• Livestock as a Source: In New Mexico, USA, there were numerous instances of mercury poisoning brought on by consuming livestock that had been fed grain contaminated with mercury.
• Grain Flour as a Source: Similar exposure occurred in Iraq, where over 6,000 people consumed flour made from wheat that had been methyl mercury-treated.

Minamata Disease - Symptoms

• Concentric constriction of the visual field (narrowing of the field of vision), hearing loss, disequilibrium (impairment of faculties for maintaining balance), speech impediments (speech becomes slurred and unclear), and tremors (trembling of the hands and feet) are among the symptoms of Minamata disease.
• Sensory disorders in the distal portion of the four extremities include loss of sensation in the hands and feet (eye movement becomes erratic).
• In extremely severe cases, patients become insane, lose consciousness, and sometimes even pass away.
• In moderate situations, it is difficult to tell the condition from other illnesses like headache, chronic exhaustion, and a generalised inability to discriminate taste and smell.

Minamata Disease - Treatment

Depending on the condition's severity and the symptoms present, different treatments may be necessary. However, some established procedures that are adhered to are:

• Mitigating Exposure Source: Locating and isolating the exposure source in order to stop any additional exposure. In many ways, this is a requirement for treatment and is certainly the first step.
• Using Chelating Agents: The most crucial part of treatment is utilizing chelating agents to remove mercury from the body.
  • Chelating chemicals react with and bind to body tissue, preventing heavy metals like mercury from doing the same.
  • This clearly has its own set of adverse effects, therefore experts advise using substances with low levels of toxicity.
  • Mercury may be redistributed and may even reach the brain when chelating agents are used.

Minamata Disease - Minamata Convention

• An international environmental agreement called the Minamata Convention on Mercury attempts to safeguard the environment and public health from the damaging effects of mercury and its derivatives.
• It discusses particular human actions that are causing widespread mercury pollution.
• Over the future decades, it's anticipated that this Convention's implementation will lessen mercury pollution.
• The agreement was signed in 2013 and became effective in 2017.
• It is an international agreement that the United Nations Environment Programme (UNEP) oversees.
• India ratified the Minamata Convention in 2018 and is a party to it.

*To know more about the topic, click this link Minamata Convention

Conclusion

Toxic substance contamination of the environment causes severe harm, including danger to life and destruction of the living environment. The world has learned from this instance of the Minamata Disease that actions that prioritize economic objectives but pay insufficient attention to the environment cause a variety of major damages, including health damage, and that it is difficult to recover from the damage later on. Because the remedies for these losses are expensive and time-consuming, it is obvious from an economic perspective that these activities are not a wise choice.

FAQs 

Q1: What is Minamata disease?

Q2: What are the symptoms of Minamata disease?

Q3: What causes Minamata disease?

Q4: How can Minamata disease be treated?

Q5: What is the Minamata Convention?

MCQs 

1. What is the primary cause of Minamata disease?

A) Lead poisoning

B) Methylmercury contamination

C) Arsenic contamination

D) Pesticide exposure

2. Where was Minamata disease first identified?

A) Hiroshima

B) Minamata Bay, Japan

C) New Mexico, USA

D) Bangladesh

3. What is a significant symptom of Minamata disease?

A) Chest pain

B) Numbness in the hands and feet

C) Skin rashes

D) Fever and chills

4. What was the main source of mercury contamination in Minamata?

A) Coal mining

B) Industrial waste discharge into the water

C) Pesticide use

D) Agricultural runoff

5. What is the Minamata Convention focused on?

A) Preventing nuclear accidents

B) Reducing plastic pollution

C) Reducing and eliminating mercury pollution

D) Protecting endangered species

GS Mains Questions and Model Answers

Q1: Discuss the impact of Minamata disease on public health and the environment.

Answer: Minamata disease had a profound impact on both public health and the environment. Public health was severely affected, with thousands of individuals suffering from mercury poisoning, leading to neurological damage, and in some cases, death. The disease caused irreversible harm to individuals and affected multiple generations due to its congenital form. Environmentally, the contamination of Minamata Bay severely impacted the local aquatic ecosystem, affecting both fish and the animals that relied on them for food. The widespread contamination led to significant changes in environmental policies and prompted global action against mercury pollution.

Q2: Explain the role of industrial pollution in the development of Minamata disease.

Answer: Industrial pollution, specifically the discharge of mercury-laden waste into Minamata Bay by a chemical plant, was the primary cause of Minamata disease. Mercury accumulated in the food chain, contaminating fish and shellfish, which were staple foods for the local population. The poisoning of aquatic life led to the widespread health crisis among humans who consumed contaminated seafood. This case highlighted the dangers of unregulated industrial waste disposal and the need for stringent environmental protection measures.

Q3: How did the Minamata Convention contribute to the global effort to manage mercury pollution?

Answer: The Minamata Convention, adopted in 2013, was a significant international treaty aimed at reducing and eventually eliminating mercury pollution. The convention focuses on controlling mercury emissions from industrial processes, promoting mercury-free products, and improving the management of mercury waste. It also encourages the safe storage of mercury and its environmentally sound disposal. By setting binding targets and promoting cooperation among countries, the Minamata Convention plays a critical role in addressing global mercury contamination and protecting public health and ecosystems from the harmful effects of mercury.

Previous Year Questions on Minamata Disease

1. UPSC CSE 2020

Q1: "Discuss the causes and effects of Minamata disease, and highlight the global response to mercury pollution."

Answer: Minamata disease is caused by methylmercury poisoning, resulting from industrial pollution in Minamata Bay, Japan. The disease affected thousands of people who consumed contaminated seafood, causing neurological damage, and in some cases, death. The global response included the Minamata Convention, an international treaty that aims to reduce mercury pollution, manage its use in industrial processes, and protect human and environmental health. The convention is a vital step in addressing the harmful effects of mercury on public health and ecosystems.

2. UPSC CSE 2019

Q2: "Explain the significance of the Minamata Convention and its role in controlling mercury pollution globally."

Answer: The Minamata Convention, signed in 2013, is a key international agreement focused on reducing mercury pollution globally. It provides a framework for the reduction of mercury emissions and the management of mercury-containing products, with an emphasis on minimizing its impact on human health and the environment. The convention calls for the phase-out of mercury use in many products, the regulation of industrial processes, and the reduction of mercury emissions. Its role in controlling mercury pollution is significant as it ensures global cooperation in tackling the harmful effects of mercury exposure, as demonstrated by the Minamata disease tragedy.