Several Japanese medical experts want blood stem cell bank workers at the nuclear plant of Fukushima Daiichi in trouble. The cells would be used as a treatment in case of high radiation exposure makes a sick worker. But the proposal raises eyebrows among American experts, who say it probably would not save many lives.
In a letter today The Lancet Tetsuya Tanimoto of the Japanese Foundation for Cancer Research and four others noted that the introduction of nuclear power radiation leak under control could last for months or years, and some workers could be accidentally exposed to high levels of radiation. While high doses of radiation can possibly cause cancer, the immediate health effect is to destroy dividing cells, including blood cells that the immune system clears. The authors point out that some workers after bone marrow transplantation 1986 Chernobyl disaster received given, and two Japanese nuclear workers were given stem cell transplants after an accident 1999.
Stem experts transplant cells in Japan and Europe have approved the bank workers stem cell Fukushima, and medical workers in Japan and Europe are there to help. (The cells would be obtained by giving workers a medicament which pushes stem cells from bone marrow blood in the bloodstream and then hang them to a machine that filters stem cells.)
Other questions the rationale. It is not known if a transplant of donor stem cells have helped some Chernobyl workers survive; they received several different types of cells, and there was no control group, bone marrow transplant expert David Weinstock of the Dana-Farber Cancer Institute in Boston. The two Japanese nuclear workers, they eventually die of organ failure caused by radiation anyway, notes radiologist Fred Mettler, of the University of New Mexico.
Moreover, giving Fukushima workers their own stem cells should work better than the donor cells because the patients own cells will not be rejected by the immune system. Experience with patients with lymphoma who receive a transplant of their own blood cells or bone after radiation therapy to clear their cancer, showed "there is no doubt that it helps," says expert in bone marrow transplant Nelson Chao of Duke University in Durham, North Carolina.
But a stem cell transplant would only allow a worker has received a dose of about 5 to 10 gray grays of radiation, Chao said. (Below patients survive with other treatments, above, they were going to die anyway damage to the intestines and lungs.) Workers would also have had their whole body exposed to radiation. If workers are partially protected, as the three who entered the radioactive water last month, affected their bone marrow will restore the destroyed cells.
The number of the 800 workers of the Fukushima plant could receive radiation in the narrow range of dose "would be quite limited," said Chao. A scenario that might make more sense, Chao said, is whether stem cells have been reserved for a subset of some 100 workers who were sent only in high-radiation areas.
Chao he said "a lot of emails circulating" in response to The Lancet letter, and he expects a US group that he and Weinstock are a part of, radiation injury treatment system (of RITN) may post a reply. Nuclear Safety Commission of Japan also opposed the plan because experts and public disagreements, including a concern that it could give workers a false assurance and make them less careful to take risks.
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