More than 300 families across the country will host 150 children from Chernobyl over the next month and become their Irish "mums and dads".
Adi Roche's charity Chernobyl Children International (CCI) has organised the trip of a lifetime for the youngsters affected by the nuclear disaster in the city.
A host of activates including swimming, barbecues, horse riding and a big day out with broadcaster Joe Duffy have been lined up for the children, some of whom have never been outside the walls of medical institutions.
Ms Roche told the Herald that families had opened their homes and their hearts for the children on the 30th anniversary of the disaster.
"Even if they have to go back to the institution, they will always know that they have an Irish 'mammy and daddy'.
"We say they are like little ambassadors, they have come from the heart of Chernobyl to the heart of the Irish people," she said.
The Chernobyl disaster began in the early hours of April 26, 1986, when a botched test at the nuclear plant in then-Soviet Ukraine triggered a meltdown.
Deadly clouds of radioactive material were spewed into the atmosphere, forcing tens of thousands of people from their homes and doing untold long-term health damage.
Ms Roche said she began the Rest and Recuperation Programme after receiving a fax from Belarus, which was then in western Ukraine.
"We got a fax from the doctors saying 'for God's sake get the Rest and Recuperation Programme children out'.
"They need clean water, clean air, and clean food. Children were the most vulnerable," she said.
The programme was established to provide a health-boosting reprieve from the toxic environment and high levels of radiation to which they are exposed.
The dangerous environment has been maintained due to the ongoing recontamination by forest fires in the affected regions.
Shannon Airport was yesterday full of cheer as the children arrived and met their host families.
"It warms everyones' heart here today to see the excitement on the children's faces as they arrive safe and happy into Shannon.
"Our wonderful volunteers have opened their hearts and their homes to these children every summer, children who so desperately need our help.
"While the Chernobyl accident happened 30 years ago, the consequences last forever," Ms Roche said.
"My heartfelt gratitude goes to the volunteers who offer hope to the children who the world has largely forgotten," she added.
Recent studies have shed light on the benefits of rest and recuperation to the children who live in some of the world's most radioactive contaminated lands.
It is expected that radiation levels in the children will drop by nearly 50pc on the trip - adding up to two years to their life expectancy.
Dr Ian Fairlie, a nuclear biologist, said in a recent report on the effects of Chernobyl "beyond a reasonable doubt" children's health improves greatly when they are removed form toxic environs.
Since 1991, 25,000 children from Belarus and western Russia have come to Ireland with CCI on this Rest and Recuperation programme.
Among the children who arrived yesterday was 13-year-old Maryna, who was abandoned to a medical institution.
She suffers from Cerebral Palsy but has been making great progress thanks to the care of CCI carers and volunteers
Maryna will stay with her 'adopted' mother Trina Gilchriest and her family in Dublin.
Nastya (16) was abandoned at an institution in Belarus as a baby. She has cerebral palsy and had never been outside the walls of the institution because she didn't have a wheelchair.