Godzilla, a theropod dinousaur of the genus gojirasaurus.

The twenty-three crew-members of the fishing boat Lucky Dragon #5 (Daigo Fukuryu Maru).

Radioactivity from hydrogen bomb testing at Bikini Atoll, 1954.

Intensely radioactive fallout from the first fission-fusion-fission bomb---exploded at Bikini Atoll, March 1, 1954---blanketed the boat, gently snowing down for three hours as the crew went about their business. No safety measures were taken, as they had no idea what the white ash was and ionizing radiation cannot be sensed. The "death ash" (shin no hai) stuck tenaciously to things, remaining on hair, fingernails, skin, clothes, and all the surfaces on the boat for their two week journey home. Breathing, drinking, and eating brought the radioactivity inside of their bodies. One man slept with a sample of the novel substance under his pillow.

Highly radioactive body; leaves trail of radioactive residue.

Radioactive plasma breath/ray.

Nuclear pulse locomotion.

Increase in size from 12 meters tall, weighing 60 metric tons, to (at least) 50 meters tall and weighing 20,000 metric tons.

Ability to reproduce a-sexually.

Ability, rather necessity, to ingest radioactive materials, e.g., nuclear reactors.

Eventually, Godzilla succumbed to his own internal nuclear disaster: a combination of emotional grief over the death of his child, the stress of physical attack, and an apparent malfunction caused his atomic heart to melt-down. As the melt-down progressed it manifested itself physically in the form of glowing red patches on Godzilla's epidermis, and his normally blue radioactive breath glowed red.

EARLY:
nausea and vomiting; loss of appetite; fatigue; skin became itchy, painful, and inflammed; painful eyes.

LATER:
sores developed; loss of hair; temporary sterility; beta ray burns turned exposed areas of skin dark brown; discharge from the eyes and ears; jaundice; swollen livers; depressed counts of white and red blood cells, platelets, and bone marrow cells.

FINAL:
Aikichi Kuboyama died six months after exposure, from liver and blood damage, despite intensive medical treatment. Everyone else was hospitalized for over a year and lived with increased probabilities of cancer and shortened life-span. Seventeen members of the crew remain alive today.

An early biotechnological experiment fusing of one of Godzilla's immortal cells (G-cell) with a previously created rose/human hybrid cell created Biollante. Biollante is further mutated under the influence of Godzilla's radioactive breath. A creature capable of emitting corrosive radioactive sap...

One of Biollante's rose/human/Godzilla cells made its way into outer space where it fused with a crystalline alien [cosmic] life-form in a black hole creating SpaceGodzilla.

The intense radioactivity of Godzilla's nuclear immolation revived and further mutated his son Godzilla Junior. Godzilla Junior originally mutated from a gojirasaurus under the influence of residual radioactivity from the atomic tests in the Marshall Islands.

The bomb, code name BRAVO, of the test series CASTLE, was the most powerful explosion ever, over 1,000 times greater than the A-bomb used on Hiroshima. The yield, some 15 megatons, was more than twice the expected maximum. The weather turned officially "unfavorable," i.e., the wind blew in the wrong direction, but they detonated it anyway. These factors help explain why the boat got hit from 20 miles beyond the perimeter of the "safety zone."
The military moved 20 ships to adjust for the weather; they did nothing to prevent the nearby Marshallese inhabitants from being exposed
... but that's another story.

The Lucky Dragon introduced the world to fallout, adding a whole new dimension of fear and fatality to an already menacing nuclear reality: death dealt from a hundred miles away.

Treatment was problematic, partly because no one had ever suffered the effects of fallout before, the unique combination of doses from both inside and outside the body; in addition, the U.S. refused to tell the Japanese what the contents of the fallout were, under the rubric of national security.

To make matters worse, the U.S. dismissed the severity of the fallout and denied responsibility for the consequences of this action. This attitude did nothing to relieve the already embroiled anxieties about Americans and Atomics.

Upon his death, Aikichi Kuboyama became the first hydrogen bomb casualty, as well as the first known victim of nuclear fallout.

The fallout over the fallout from BRAVO extended well beyond the lives of these twenty-three individuals. The nine tons of contaminated fish they brought home was sold in four major cities and eaten by at least 100 people before anyone realized what had happened. This discovery sparked a national crisis, the "tuna panic." People stopped eating marine products, usually their major source of protein. The fishing industry was devastated as the price of fish plummeted; the fishermen, living near poverty level already, were especially hard hit. Over the course of ten months 457 tons of fish were confiscated and destroyed.

Among the perverse benefits of BRAVO: As scientists tried to find out why contaminated fish continued to be brought in over the next ten months, even as the radioactivity in the ocean dispersed, they found that radioactivity in the ocean allowed them to trace out paths of ocean currents.
They also discovered the principle of bio-accumulation: plankton "eat" the unusual chemicals, concentrating them, then get eaten by larger organisms; then, big fish eats little fish right on up the line.

The Lucky Dragon became a symbol for the world wide anti-nuclear movement.