Child Lead Exposure Determined from Measurement of X-Ray Fluorescence of Teeth in Situ

X-ray fluorescence from lead when irradiated by gamma rays from a Co-57 source was utilized to measure the lead concentration in children´s teeth in situ. The sensitivity of the method was adequate to detect 15 PPM from a gamma ray exposure to the tooth approximately 1/10 the exposure of a routine dental x-ray examination. The tooth lead levels assayed using x-ray fluorescence correlated well with chemical assay techniques for both extracted permanent and shed primary teeth. Thirty children from the Children´s Hospital of Philadelphia suspected of having elevated lead levels had tooth lead levels measured in situ determined using the x-ray fluorescent technique. The tooth lead concentration varied from a low of 16 PPM to a high of 56 PPM.