Deciduous teeth of Finnish children born in 1958-1967 were analysed for strontium-90 by means ofčCerenkov radiation. The strontium–90 content was about 9 pCi/gCa in children born in 1963-1964; the values decreased strongly in the subsequent cohorts of children. The strontium–90 content of the deciduous teeth varied in perfect unison with that of COW'S milk (r = +0.99). The results confirm that deciduous teeth provide a practical and accurate indicator of the total body burden of bone–seeking environmental pollutants.