External thyroid absorbed dose estimates were based on integrated photon exposure given previously and based on an adjustment for living pattern in a variable exposure rate environment. Further detail about the adjustment can be found in (Na80) and (Le83). Some questions about the external beta dose to the thyroid were expressed by Cronkite (Cr81). The thickness of tissue overlying the thyroid ranges from 0.4 to 2.0 cm, average 0.82 cm, and does not correlate with age or body weight very well (ICRP74). The minimum beta energy for penetration of 0.82 em of tissue was estimated to be 1.8 MeV. At Rongelap Island about 70% of the population has skin lesions on some part of the neck appearing initially about 21 days post exposure (Cr56). thousand rads. netic energy. This would imply a skin surface dose of several Only a small per cent of the beta flux was above 1.8 MeV in kiOf this higher energy flux, only a small fraction would penetrate 0.82 cm of tissue and deposit energy in the thyroid. this pathway was considered insignificant. 37 Thus thyroid dose from