[en] As part of a wider programme of investigations being carried out in N. Wales, a study of the radioactivity of sheep droppings has been undertaken, some preliminary results from which are presented in this note. (author)

[en] Any reliable estimation of the frequency with which low doses of ionising radiation cause cancer requires a detailed study of records from very large exposed populations, over long periods of time following exposure, and with an exact comparison of cancer frequencies with those of equally large or larger populations which have not been similarly exposed, but in which the cancer incidences of mortalities have been ascertained with equal efficiency. Special problems occur in finding appropriate comparison groups for occupationally exposed workers and for patients treated or investigated radiologically. These are discussed, together with the difficulties in ensuring comprehensive recording of total cancer incidence, rather than of mortality. (author)

[en] Concentrations of radon-222 can vary widely both indoors and out of doors. Some of the causes of the variations are unpredictable, but diurnal and seasonal patterns of variation can be discerned if radon fluctuations are averaged out. The average diurnal variation in radon concentration out of doors has been shown to follow the average pattern of variation in atmospheric temperature gradient very closely. Indoors a similar diurnal pattern is observed, and seasonal variations also follow a pattern. The average radon concentration indoors in January (the coldest month) is about twice that in July. The implications of these variations for the measurement of exposures of people to radon decay products are discussed. (author)

[en] During the analyses of sheep and cattle tissues following the Chernobyl accident, the only nuclide routinely detected in the short count times being used, apart from the caesium isotopes and ¹³¹I, was ^110mAg in the liver. The table presented compares the activity concentration of ^110mAg and ¹³⁴Cs in the liver of sheep slaughtered during the first four months after deposition from various sites in Cumbria. The ratio of ^110mAg to ¹³⁴Cs ranged from 0.09 to 1.67 with a coefficient of variation of 102%. (author)

[en] The whole-body dose from inhaled radionuclides is a complex function of factors describing exposure and physiology. Exposure-related factors may be estimated by considering likely emission rates combined with measured time-varying meteorological (transport) parameters and estimated exercise patterns. Physiological factors, strongly influencing radionuclide intake and consequent radiation dose, have been catalogued as functions of age and activity level. Both exercise patterns and physiological factors are related to age of the exposed individual. Combining these factors permits estimates to be made of the span of exposures that may be expected in a typical population. The ratio of highest to lowest radionuclide intake is predicted to be of the order of 40, suggesting that specification of an 'average' value may be misleading if this value approaches regulatory limits. Individuals exposed to maximal risk may be identified, and are likely to be active children. Activity pattern (lifestyle) is a primary determinant of risk. (author)

[en] As a result of experience gained from the Chernobyl accident, and evidence about radiation risks provided by the latest Hiroshima and Nagasaki studies, NRPB wishes to review its recommendations on emergency reference levels of dose for the public, and to provide guidance on worker protection in accident situations. This paper contains the authors suggestions for the form new NRPB recommendations might take. The basic principles for planning actions to protect the public are discussed and dose levels for the introduction and withdrawal of countermeasures are proposed. Dose levels are given which it is suggested should not be exceeded by workers involved in dealing with an accident and corresponding dose levels for workers carrying out recovery operations. Comments are invited. (author)

[en] The main hazard in the early phase after Chernobyl was radioiodine. Thyroid doses were esimated separately for (i) zones of strict control, (ii) most contaminated provinces (iii) the whole central European region of the USSR. Distinction was made between children under the age of 7 years at the time of the accident and the rest of the population. In the later phase the main concern is whole-body exposure to radiocaesium. Doses were calculated for the same areas and age groups as radioiodine. The following were considered: thyroid malignancies, leukaemia, other types of cancer, genetic defects and teratogenic anomalies. A stastistically significant excess over the spontaneous level is unlikely to be detectable for these effects, with the possible exception of thyroid disorders. The risk was greatly reduced by preventive measures, in particular lifetime doses have been restricted by establishment of a limit of 0.35 Sv. (author)

[en] The radioactive releases from the Chernobyl accident reached Syria on 7 May 1986. Levels of radioactive contamination in milk, soil, grass, etc, were measured using gamma spectrometry. Population dose by a number of routes was calculated. Projected doses were below the emergency action levels. (author)

[en] In this note the ICRP 48 and ICRP 56 models for plutonium are compared with each other and with the comparable predictions of the Oak Ridge and Harwell/Chilton dosimetric models using a common Monte Carlo computer code. (author)

[en] Diagnostic radiology is the largest man-made contribution to the population dose in the United Kingdom. It is therefore of importance to monitor and reduce radiation dose levels in diagnostic radiology, if the principle of 'as low as reasonably achievable' is to be attained. The work presented here describes the adaptation of an electronic personal organiser or filofax (PSION II LZ64, PSION plc, London), which when used in combination with a Diamentor dose-area product meter will store information on the patient and examination as well as the dosimetry results. The electronic personal organiser can be linked to a thermal printer to provide a permanent record of the patient dosimetry information. The electronic personal organiser can be interrogated via a computer link for scientific analysis on a separate computer. (author)