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Accumulation of strontium-90 in human teeth as a result of nuclear fall-out.

Strontium-90, resulting from nuclear fall-out, is taken up by bone and tooth during periods of calcification. The results are reported of a dental survey carried out by the Royal Navy since 1959. There is a time lag of three to four years between the development of the roots and the development of the crowns in relation to the total period of calcification which allows the probable rate of uptake to be determined from tooth assays. Since there is close correlation between tooth and bone levels, tooth assays may be used to monitor bone levels in living subjects.