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In certain Hiroshima neighborhoods, radiation measurements using thermoluminescence dosimetry (TLD) exceed what can be explained by the initial gamma-ray doses and uncertainties from the Dosimetry System 2002 (DS02). This problem was not previously recognized as being isolated to certain parts of that city. The ratio between TLD measurements and DS02 dose calculations for gamma rays appear to grow larger than unity up to more than three with increasing ground range, but closer examination shows the excess TLD dose (0.1, 0.2, or possibly up to 0.8 Gray) is correlated with certain neighborhoods and could be due to radioactive fallout. At Nagasaki, the TLD measurements do not show this same excess, probably because there were no TLD measurements taken more than 800 m downwind (eastward) from the Nagasaki hypocenter, so that any small excess TLD dose was masked by larger initial gamma-ray doses of 25-80 Gray in the few downwind samples. The DS02 Report had noted many measurements lower than the DS02 calculation for several Nagasaki TLD samples, independent of ground range. This was explained as being the result of previously unaccounted urban shielding which was observed from Nagasaki pre-bomb aerial photos. However, the Hiroshima excess TLD dose issue was not resolved. If the excess TLD doses at Hiroshima are an indication of fallout, it may be possible to use additional TLD studies to make better estimates of the locations and radiation doses to survivors from the fallout after the bombings at both cities.

Background and Purpose: Although radiation skin injuries associated with interventional radiology have been known as a critical issue, there are few reports mentioning direct measurement of the entrance skin dose (ESD). Thus, the purpose of this study was to clarify the regional distributions of ESDs in neurointervention., Materials and Methods: Using photoluminescence glass dosimeters (PLDs), we measured the ESDs in 32 patients with a median age of 61.5 years. Angiographic parameters, including exposure time, dose-area product (DAP), and the number of digital subtraction angiography (DSA) studies and frames, were recorded. The ESDs of operators were analyzed by the same method., Results: The maximum ESD of 28 therapeutic procedures was 1.8 +/- 1.3 Gy. Although the averaged ESD on the right temporo-occipital region was higher than that in other regions, disease-specific patterns were not observed. Statistically positive correlations were found between the maximum ESD and exposure time (r = 0.5283, P = .005), DAP (r = 0.7917, P < .001), the number of DSA studies (r = 0.5636, P = .002), and the number of DSA frames (r = 0.8583, P < .001). As for operators, ESDs to the left upper extremity were significantly higher than those to other regions. However, most of the ESDs were <0.2 mGy. Lead protective garments reduced the exposure doses to approximately one half to one tenth., Conclusion: It was shown that the regional ESD could be measured by applying the PLD. This method should contribute to reducing the dose accumulation in patients as well as in operators.

We have applied the thermoluminescence dosimetry technique to measure the total external dose from all the nuclear explosions in a few locations near the Semipalatinsk nuclear test site in Kazakhstan. The technique was optimized at our laboratory by fundamental study of the method of thermoluminescence dosimetry. The measured values of each sample at 10 mm depth were 248+/-102 mGy (KSD-1), 30+/-76 mGy (2(1-3)), 222+/-63 mGy (2(3-2)), 217+/-55 mGy (2(4-1)). The results are part of an international intercomparison exercise using bricks collected from the areas surrounding the Semipalatinsk nuclear test site.

The doses of radiation streaming through a labyrinth were measured using thermoluminescence dosemeters (TLDs) and neutron moderators for TLDs at the neutrino beam line of the 12 GeV proton accelerator facility of High Energy Accelerator Research Organization (KEK). The calculated doses using the Monte Carlo code, MCNPX basically agreed with the experimental results. However, unexpectedly, the calculated neutron doses were smaller than the measured ones along the upstream side of the labyrinth.

We have developed a method for obtaining the cumulated activities in organs from radionuclides, which are injected into the patient in nuclear medicine procedures, by external exposure measurement with thermoluminescent dosimeters (TLDs) which are attached to the patient's body surface close to source organs to obtain information on body-surface doses. As the surface dose is connected to the cumulated activities in source organs through radiation transmission in the human body which can be estimated with the aid of a mathematical phantom, the organ cumulated activities can be obtained by the inverse transform method. The accuracy of this method was investigated by using a water phantom in which several gamma-ray volume sources of known activity were placed to simulate source organs. We then estimated by external measurements the organ cumulated activities and absorbed doses in subjects to whom the radiopharmaceuticals 11C-labelled Doxepin, 11C-labelled YM09151-2 and 11C-labelled Benzotropin were administered in clinical nuclear medicine procedures. The cumulated activities in the brain obtained with TLDs for Doxepin and YM09151-2 are 63.6 +/- 6.2 and 32.1 +/- 12.0 kBq h MBq-1 respectively, which are compared with the respective values of 33.3 +/- 9.9 and 23.9 +/- 6.2 kBq h MBq-1 with direct PET (positron emission tomography) measurements. The agreement between the two methods is within a factor of two. The effective doses of Doxepin, YM09151-2 and Benzotropin are determined as 6.92 x 10(-3), 7.08 x 10(-3) and 7.65 x 10(-3) mSv MBq-1 respectively with the TLD method. This method has great advantages, in that cumulated activities in several organs can be obtained easily with a single procedure, and the measurements of body surface doses are performed simultaneously with the nuclear medicine procedure, as TLDs are too small to interfere with other medical measurements.

Thermoluminescence dosimetry measurements of gamma rays produced by the atomic bomb in Hiroshima were made by the predose technique using eight ceramic samples collected from five buildings located at distances between 1271 and 2051 m from the hypocenter. The results of our measurements are compared to both the newer dose estimates (Dosimetry System 1986) and older dose estimates (Tentative 1965 Doses) for survivors of the Hiroshima atomic bomb. In comparison with the older estimates, our results are larger by a factor of 2.3 at 1271 m and 3.9 at 2051 m. Our results and the newer estimates for Hiroshima differ by a factor of only 1.14 +/- 0.16 on the average.