Does plutonium intake in workers affect lymphocyte function?

Measurements of mononuclear cells in peripheral blood of persons with long-term internal depositions of plutonium indicate a preferential reduction in suppressor T-lymphocytes (Ts) in some individuals. The decrease in Ts cells is apparently due to altered radiosensitivity, which is demonstrated in cultured cells subjected to in vitro X ray radiation. The increase in ratios correlates with the quantity of plutonium deposition in these subjects, but there are wide individual differences. Confirmatory studies are needed in other persons with long term alpha or chronic gamma radiation exposure. If confirmed, the implications would include recognition of a potential mechanism for an enhanced immune system reactivity in some individuals exposed to chronic low level radiation. (author)