Mutsuko Yoshida is eager to gather as many details and facts as possible as a storyteller. But when it comes to accounts of hibakusha, she knows there has to be a certain line drawn.

As she collects stories by talking with atomic bomb survivors, Yoshida understands the intricate and personal nature of their experiences and how sharing them with her is a big decision on the part of hibakusha.

(Mutsuko Yoshida)

The important mission, she says, is to serve as a bridge between aging survivors and people born after the 1945 U.S. atomic bombings of Hiroshima and Nagasaki that led to Japan's surrender in World War II.

At 76, Yoshida, who is not an atomic bomb survivor herself, is now taking on a new challenge: going overseas to share the story of one hibakusha in English.

In what will be Nagasaki's first dispatch of an English storyteller who inherits hibakusha stories, she will travel to Portugal from late September for a series of gatherings in three cities that she, along with local officials, hopes will inject momentum into the drive for eliminating nuclear weapons.

"We tend to think getting burned or injured is symbolic of the suffering of the atomic bombing but that is not all," Yoshida said.

"Those who had radiation exposure afterwards have also continued to live with the fear of not knowing what would happen and with their inner struggles."

She plans to share the story of a male hibakusha who, then aged 9, was not near the hypocenter at the time of the bombing on Aug. 9 but was exposed to radiation in the following days. The bombing killed an estimated 74,000 people by the end of 1945.

Through her storytelling, Yoshida hopes to help deepen understanding abroad of what an atomic bomb can do to ordinary people.

The Japanese term "hibakusha" refers not just to atomic bomb survivors but also to people who entered a 2-kilometer radius of ground zero within two weeks of the respective bombings.

Like Yoshida, people who try to pass the baton from atomic bomb survivors to future generations say sharing is not always easy despite its increasing urgency.

The extent to which each survivor has suffered from the atomic bombings -- directly or indirectly -- varies. And to atomic bomb survivors, it means exposing themselves, and often their family members, by talking about what happened.

"It's true that there are hibakusha who do not want to share everything that happened. The person may want to share it but doing so would also involve their family members and put them in the spotlight too," Yoshida said.

(Atomic bomb survivors sing in Nagasaki on Aug. 9, 2018, during a ceremony marking the 73rd anniversary of the U.S. atomic bombing of the city)

This year marked the 73rd anniversary of the atomic bombings of Hiroshima on Aug. 6 and Nagasaki on Aug. 9.

As of March, Japan had nearly 155,000 atomic bomb survivors, according to government data. People who entered a 2-kilometer zone in the two-week period and have been recognized as hibakusha accounted for less than a quarter of the total.

The average age of hibakusha now stands at 82.06, prompting a hard look at how the experiences of the Hiroshima and Nagasaki bombings can be shared and remembered.

Faced with the aging of atomic bomb survivors, Nagasaki has been training people to become storytellers on behalf of hibakusha. Sending Yoshida to Portugal is a critical step into new territory.

"The hope is to give people outside Japan something to think about," said an official in Nagasaki involved in the project. "If more people understand the realities of the atomic bombing, it could lead to international efforts toward the abolition of nuclear weapons."

Nagasaki and Portugal's Porto marked the 40th anniversary of their sister-city relationship in 2018.

Yoshida's trip will come weeks after U.N. Secretary General Antonio Guterres, a Portuguese diplomat, became the first chief of the international body to attend Nagasaki's annual memorial ceremony.

Making their case for a world free of nuclear weapons, the mayors of Nagasaki and Hiroshima both touched on the influence that civil society can generate. Nagasaki Mayor Tomihisa Taue stressed the importance of learning history and listening to accounts of wartime experiences.

"There are many things that each and every one of us can do to help bring about the realization of a peaceful world," Taue said in his peace declaration during the Aug. 9 ceremony.

(U.N. Secretary General Antonio Guterres, left, talks with atomic bomb survivors in Nagasaki on Aug. 8, 2018)

Ahead of her trip, former English teacher Yoshida spends hours trying to figure out how best to get her message across as she puts the finishing touches on her roughly 30-minute performance with help and advice from a Canadian native.

She is feeling the weight of responsibility as a messenger.

"I speak for hibakusha, not myself," Yoshida said. "But my message is that an atomic bomb, once used, makes people suffer for years and years. You can't put a period to it."