Summaries of articles in this issue

Abstract

Review: Radiological protection of the environment from the Swedish point of view L-E Holm et al (235-247) This is a review of the Swedish regulatory experiences of protecting the environment against harmful effects of ionising radiation. The Swedish radiation legislation aims at protecting both humans and the environment. The Swedish Parliament has established national environmental quality objectives with the purpose to hand over to the next generation a sustainable society. The Swedish Radiation Protection Society (SSI) has the responsibility for the objective of `A Safe Radiation Environment'. In its regulations concerning the final management of spent nuclear fuel and waste and releases of radioactive substances from nuclear facilities, SSI has formulated environmental aims that focus on protection of biodiversity and biological resources.Radiological impacts on organisms other than man of long-lived radionuclides M C Thorne et al (249-277) A case study is presented in which an assessment is made of the radiological impacts on organisms other than man of various long-lived radionuclides of importance in solid radioactive waste disposal. Threshold dose rates for the induction of significant deleterious effects on communities are estimated and it is shown that compliance with radiological protection standards appropriate to man will ensure that such thresholds are not exceeded. These results apply only to the radionuclides and assessment context considered, and the authors identify the need to build up a dossier of such case studies in support of the ICRP contention that the standard of environmental control needed to protect man from the effects of ionising radiations would ensure that other species were not put at risk.The proportion of thyroid cancers in the Japanese atomic bomb survivors associated with natural background gamma radiation M P Little (279-291) Absolute and relative risk models are fitted to the Japanese atomic bomb survivor thyroid cancer incidence data followed up over the period1958-1987, taking account of natural background radiation. Over 50% of the excess cases associated with either the atomic bomb radiation or natural background radiation are linked to exposures under the age of 20, irrespective of the assumed risk model or natural background dose rate (in the range 0.5-2.0 mSv/year). The excess risk is overwhelmingly concentrated among females, again irrespective of the assumed model or natural background dose rate. Depending on the assumed natural background dose rate and risk model between 4% and 32% of the thyroid cancers in this cohort may be associated with natural background radiation. The proportion of the thyroid tumours attributed to the atomic bomb radiation is between 19% and 22%, dependent on the assumed background radiation dose and risk model.Choice of alpha-probe operating voltage to suit a wide range of conditions R B Bosley and J A Simpson (293-303) Scintillation probes are used throughout the nuclear industry to monitor for alpha radiation. The ability to detect alpha radiation is dependent on a number of factors including the efficiency of the probe, and the surface being monitored. In the past, it has been assumed that maximising the operating voltage and therefore the probe efficiency will improve the ability to detect alpha radiation. However, the work presented here suggests the characteristics of the surface being monitored have far more effect on the results of alpha monitoring than the choice of operating voltage.