L-line X ray fluorescence of tibial lead: correction and adjustment of radiation risk to ICRP 60

Effective doses E (ICRP 60, 1991) to adults and children from a non-invasive assessment of tibial bone lead by L-line X ray fluorescence (LXRF) are calculated using published absorbed dose data. E is 1.0 μSv for a 5 year old child and 0.3 μSv for an adult. LXRF effective dose equivalents HE (ICRP 26, 1987) calculated from the same data were previously overestimated about twofold and should have been reported as 1.7 μSv for a 5 year old child and about 0.7 μSv for an adult. Differences between HE and E are largely due to an ICRP recommended reduction of the tissue weighting factor wT for 'bone surface' from 0.03 (ICRP 26) to 0.01 (ICRP 60). The proportion of E from the sum of all of the wT weighted equivalent doses to tissues other than red bone marrow ranges from 48% in a 1 year old child to over 99% in adults. (author)