la ew - tissue (i.e., far beyond the 0.007 cm penetration depth assumed by Standards setting bodies in estimating skin dose. Also, one should determine whether or not there are co-relations or synergistic relation between beta-radiation and UV as there are between UV-A and UV-B in the induction of skin cancer. One might suspect that skin cancer _ is the predominate malignancy on the sun baked islands. 5. Since a large fraction of the radioactive contamination on the islands should be 905, + 90, | and since 99 percent of Sr is deposited in the skeleton, why did the authors not discuss bone dose and radia-~ tion induced bone sarcoma and carcinoma as well as leukemia from active bone marrow irradiation in the trabecular bone matrix? Published values of bone cancer coefficients range from 2 x 10° to 2.2 x 104 cancers per person rem depending on age, radionuclide, type radiation, etc. . Some of the comparisons of population exposure given do not add to the quality of the report. U.S. If natural background radiation in the causes 6 x 1074 (c/pr) 80 mrem/y x 220 x 10° persons x 107? « 10,000 lethal cancers/y in the U.S., the objective should be to reduce this background radiation - especiallythat due to phosphate rock, etc. - and not use this as an excuse to permit more malignancies. bad thing does not justify another! radiation workers in the U.S. 7. One The comparison with exposures to weakens the report. It seems odd that these writers were able to use data from BEIR III report. I have been trying unsuccessfully to get a copy of this _unpublished report for over a year. I guess the fact that this report is paid for by tax monies does not entitle university professors to a copy? 8 In estimating the genetic risk, it is not stated whether or not the risk was reduced by a factor of 10 (as is often the practice) because the exposures are at low dose and low dose rate, i.e.: _. 3 (dose rate effect for spermatogonia) x 2 (2 sexes) x 2 (dose effect) = 10. Data of Lyon et al. (Nature New Biol. 101, July 1972) suggest use of his factor of 10 may not be warranted at very low dose rates. When the authors suggested small doses of radiation might even be beneficial genetically, they might have added also that influenza If o¢