Lead content of deciduous molar enamel in Finland, as measured by proton-induced X-ray emission.

The lead content of deciduous molar enamel was measured with an accurate physical technique based on proton-induced X-ray emission. The absolute values were calibrated according to the animal bone standard of the International Atomic Energy Agency. The results obtained from five different communities indicated little difference between communities in the lead content of the deciduous molar enamel of children born in 1960-1975. The overall mean for all samples analyzed was 3.2 (SD 1.6) micrograms/g (N = 120); the highest individual value measured was 10.0 micrograms/g. Judging from the lead content of the teeth, the general population in Finland does not yet seem to be exposed to detectably higher amounts of artificially occurring environmental lead, neither in urban nor in rural areas. It would seem that naturally occurring environmental lead still plays a decisive role in the integrated long-term exposure in Finland.