According to the Environmental Protection Agency (EPA), which nuclear accident released more radioactive material into the atmosphere than all nuclear tests conducted throughout history?

• A. Palomores, Spain.
• B. Fukushima, Japan.
• C. Three Mile Island, Pennsylvania.
• D. Chernobyl, Union of Soviet Socialist Republics (USSR).

Answer: (D)

Chernobyl stands out because the explosion and ensuing fire lofted a huge plume of radionuclides into the atmosphere, spreading fallout across Europe and far beyond. The EPA states that the total amount of radioactive material released into the air from that single accident exceeded the sum of all releases from nuclear weapons testing throughout history. That makes it the largest atmospheric release among the events listed.

In contrast, the Palomares incident involved surface contamination from a crash and did not produce a comparable atmospheric plume; Three Mile Island released only a tiny amount of radioactivity to the environment due to effective containment, and Fukushima, while severe, released less radioactive material into the atmosphere than Chernobyl according to EPA assessments.