February 22, 2024

This year’s March 1 will mark 70 years since the U.S. hydrogen test explosion at the Bikini Atoll in the Marshall Islands in the Pacific, exposing about 1,000 Japanese fishing boats to radiation fallout. Among them was a tuna fishing boat whose homeport was in Shiogama (Miyagi Pref.), one of the major fishing ports in the Tohoku region.

Nearly two weeks after the U.S. H-bomb test, national dailies in Japan reported that fishermen on the Daigo Fukuryu Maru (Lucky Dragon #5) whose base was the Yaizu port in Shizuoka Prefecture were exposed to radiation fallout. In Miyagi Prefecture, a local daily, Kahoku Shimpo reported that more than ten fishing boats in the prefecture were caught in a radiation shower.

One of them, Daigo Myojin Maru (Bright God #5), was operated at a location 1,255 kilometers away from the test site on that day. On March 26, captain Abe Sosaku in his reply to a Kahoku Shimpo inquiry after returning to the Shiogama Port said, “I didn’t know that the U.S. carried out the nuclear test near our area of operation. I was really surprised at the news that our boat was affected by radiation fallout. All people on board, including me, are well.” As the captain said, there was no problem with the results of health checkups given to the 24 crewmembers at the time they entered the port, but they were ordered to stay on the ship.

On the following day, March 27, they were re-examined and were finally allowed to go their homes on the grounds that the amount of radiation detected was small.

After this incident, the price for tuna coming to the Shiogama port dropped by half.

The Shiogama City Assembly at that time adopted a resolution submitted by cross-party assemblymembers, including a Japanese Communist party assemblyperson, demanding compensation for damages caused by the nuclear test and suspension of further nuclear tests. In 1986, the assembly unanimously adopted a declaration for peace and the abolition of nuclear weapons.