Context: Recently, a district court in Hiroshima recognised survivors of the post-explosion “black rain” caused due to the atomic bomb incident in 1945, who were outside a government-defined zone at the time of the event. 

• The court clears the way for them to receive medical benefits just days before the 75th-anniversary Hiroshima bombings. 

Background

• In 1976, the Japanese government used the 1945 study in Hiroshima to demarcate the area within which people could claim to have been affected by black rain and be recognised as survivors of the nuclear blast. 
• As per the then decision, people who lived in that area during the time of the black rain could avail free medical care and other benefits if they showed symptoms related to radiation exposure. 
• Many studies conducted later have shown that black rain could have come down on an area nearly four times the size of the one demarcated by the government. 
• In 2015, 84 plaintiffs went to court against the restrictions placed on being recognised as Hibakusha, the Japanese term for the survivors of the nuclear blasts. 

What is Black Rain?

• An estimated 69 per cent of the buildings in Hiroshima were destroyed by the atomic bomb and the debris and soot from this, mixed with the radioactive fallout from the bomb, rose high into the atmosphere in the form of a mushroom cloud.
• This material combined with the vapour in the atmosphere and came down as dark drops of liquid that have been called Black Rain.
• It has been described as consisting of large, greasy drops that are much heavier than normal raindrops by survivors. 
• Its Impact- Black rain is full of highly radioactive material, and studies have shown that exposure to it can result in serious illnesses. 
• A study of 1945 showed that black rain had come down as far as 29 km away from ground zero and contaminated everything it came in contact with, and dead fish were reported floating in water bodies. 
• It has caused acute radiation symptoms (ARS) in many who were exposed to it, with reports of people suffering from nausea and diarrhoea for weeks, fever, sore throat and loss of hair. Many exposed people developed cancer over a period of time. 

About Hiroshima and Nagasaki Bombings

• The United States dropped an atomic bomb on Hiroshima on August 6, 1945, and another one on Nagasaki three days later on August 9. 
• The explosions caused by the bombs and the resultant firestorms (large fires caused by the explosion) are believed to have killed around 80,000 people in Hiroshima and around 40,000 people in Nagasaki. 
• The bomb dropped on Nagasaki was more powerful than the one dropped on Hiroshima, but it killed fewer people and its effects were confined to a smaller area due to its geographical position between hills. 
• The after-effects of those bombings still persist in the form of cancer, deformations in newborn child etc.