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Background The possible relationship between temporal variability of electrocardiographic spatial heterogeneity of repolarization and the risk of sudden cardiac death (SCD) in patients with coronary artery disease (CAD) is not completely understood. Methods The standard deviation of T‐wave morphology dispersion (TMD‐SD), of QRST angle (QRSTA‐SD), and of T‐wave area dispersion (TW‐Ad‐SD) were analyzed on beat‐to‐beat basis from 10 min period of the baseline electrocardiographic recording in ARTEMIS study patients with angiographically verified CAD. Results After on average of 8.6 ± 2.3 years of follow‐up, a total of 66 of the 1,678 present study subjects (3.9%) had experienced SCD or were resuscitated from sudden cardiac arrest (SCA). TMD‐SD was most closely associated with the risk for SCD and was significantly higher in patients who had experienced SCD/SCA compared with those who remained alive (3.61 ± 2.83 vs. 2.64 ± 2.52, p = .008, respectively), but did not differ significantly between the patients who had experienced non‐SCD (n = 71, 4.2%) and those who remained alive (3.20 ± 2.73 vs. 2.65 ± 2.53, p = .077, respectively) or between the patients who succumbed to non‐cardiac death (n = 164, 9.8%) and those who stayed alive (2.64 ± 2.17 vs. 2.68 ± 2.58, p = .853). After adjustments with relevant clinical risk indicators of SCD/SCA, TMD‐SD still predicted SCD/SCA (HR 1.107, 95% CIs 1.035–1.185, p = .003). Conclusions Temporal variability of electrocardiographic spatial heterogeneity of repolarization represented by TMD‐SD independently predicts long‐term risk of SCD/SCA in patients with CAD.

Background The possible relationship between temporal variability of electrocardiographic spatial heterogeneity of repolarisation and the risk of sudden cardiac death (SCD) in patients with coronary artery disease (CAD) is not completely understood. Purpose To investigate the prognostic value of temporal variability of T-wave spatial heterogeneity in SCD in patients with CAD. Methods The Innovation to reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study population consisted of 1,946 patients with angiographically verified CAD. T-wave morphology dispersion (TMD), which estimates the average angle between all reconstruction vector pairs in T-wave loop based on leads I-II and V2-V6, was analysed on beat-to-beat basis from 10 minutes period of the baseline electrocardiographic recording in 1,678 study subjects. The temporal variability of TMD was evaluated by standard deviation of TMD (TMD-SD). Results After on average of 7.4±2.0 years of follow-up, a total of 47 of the 1,678 study subjects (2.8%) had experienced SCD or were resuscitated from sudden cardiac arrest (SCA). TMD-SD was significantly higher in patients who had experienced SCD/SCA compared with those who remained alive (3.64±2.57 vs. 2.65±2.54, p Figure 1 Conclusions Temporal variability of electrocardiographic spatial heterogeneity of repolarisation represented by TMD-SD independently predicts long-term risk of SCD/SCA in patients with CAD. Acknowledgement/Funding Sigrid Juselius Foundation and Finnish Foundation for Cardiovascular Research

The CONRAD Project is a Coordinated Network for Radiation Dosimetry funded by the European Commission 6th Framework Programme. The activities developed within CONRAD Work Package 5 ('Coordination of Research on Internal Dosimetry') have contributed to improve the harmonisation and reliability in the assessment of internal doses. The tasks carried out included a study of uncertainties and the refinement of the IDEAS Guidelines associated with the evaluation of doses after intakes of radionuclides. The implementation and quality assurance of new biokinetic models for dose assessment and the first attempt to develop a generic dosimetric model for DTPA therapy are important WP5 achievements. Applications of voxel phantoms and Monte Carlo simulations for the assessment of intakes from in vivo measurements were also considered. A Nuclear Emergency Monitoring Network (EUREMON) has been established for the interpretation of monitoring data after accidental or deliberate releases of radionuclides. Finally, WP5 group has worked on the update of the existing IDEAS bibliographic, internal contamination and case evaluation databases. A summary of CONRAD WP5 objectives and results is presented here.

The EUropean RAdiation DOSimetry Group (EURADOS) initiated in 2005 the CONRAD Project, a Coordinated Network for Radiation Dosimetry funded by the European Commission (EC), within the 6th Framework Programme (FP). The main purpose of CONRAD is to generate a European Network in the field of Radiation Dosimetry and to promote both research activities and dissemination of knowledge. The objective of CONRAD Work Package 5 (WP5) is the coordination of research on assessment and evaluation of internal exposures. Nineteen institutes from 14 countries participate in this action. Some of the activities to be developed are continuations of former European projects supported by the EC in the 5th FP (OMINEX and IDEAS). Other tasks are linked with ICRP activities, and there are new actions never considered before. A collaboration is established with CONRAD Work Package 4, dealing with Computational Dosimetry, to organise an intercomparison on Monte Carlo modelling for in vivo measurements of 241Am deposited in a knee phantom. Preliminary results associated with CONRAD WP5 tasks are presented here. © The Author 2007. Published by Oxford University Press. All rights reserved.

Emergency response plans have long been focused on accidents at nuclear power plants. Recently, the malevolent use of radiation aimed at creating disruption in the society has been considered as a possible threat. In this kind of emergency situations casualties will most likely be members of the public and the number of affected people can vary from a few to mass casualties. There is an evident need for rapid measurements of large groups of internally contaminated people. Radiation and Nuclear Safety Authority (STUK) in Finland has obtained new monitors for thyroid and simple whole-body measurements in field conditions as a part of the continuous improving of emergency preparedness. The new monitors consist of a NaI(Tl) detector and a control unit. The monitors work as spectrometers allowing real-time spectrum analysis in the field.

Urine monitoring is the preferred method to determine exposure to soluble compounds of uranium in workplaces. The interpretation of uranium contents in workers bioassay samples requires knowledge on uranium excretion and its dependence on intake by diet. Exceptionally high concentrations of natural uranium in private drinking water sources have been measured in the granite areas of Southern Finland. Consequently, high concentrations of natural uranium have been observed in the urine and hair samples of people using water from their own drilled wells. Natural uranium content in urine and hair samples of family members, who use uranium-rich household water, have been analyzed by using ICP-MS. The uranium concentrations both in urine and hair samples of the study subjects were significantly higher than the world-wide average values. In addition, gammaspectrometric methods have been tested for determining uranium in hair samples. This method can be used only for samples with highly elevated uranium concentrations.

The 137Cs and 90Sr fallout in Finland and the content of these nuclides in milk samples, water reservoirs, fishes, and human bodies were measured.

In a preliminary study, in vivo skull measurements and in vitro urine measurements of 210 Pb and nat U have been performed to find out the individual, chronic exposure to waterborne natural radionuclides of a small group of Finnish people. For their domestic water, the studied individuals use water from drilled wells containing elevated concentrations of natural uranium and its daughter nuclides ( 234,235,238 U, 222 Rn, 226,228 Ra, 210 Po, 210 Pb). Enhanced 210 Pb and 235 U activities were observed in several people. A positive correlation is observed between the U concentration in urine (μg d -1 ) and the number of counts (cpm) in the gamma ray energy peaks originating from the decay of 235 U and 234 Th respectively. Calibration of the detector setup and the determination of background sources are in progress.

The aim of this study was to estimate the current concentrations of 90 Sr and 137 Cs in the urine of Finnish people and to estimate the doses. Two to three daily urine samples were collected from 18 adult Finnish volunteers in connection with studies of 137 Cs body burdens in 1999-2001. The 90 Sr activities in urine varied between 1.4 and I 1 mBq I 1 The 137 C, activity in urine varied between 0.36 and 56 Bq 1 1 . The daily urinary excretion was found to he 4.8-17 mBq for 90 Sr and 0.81-68 Bq for 137 Cs. Assuming that the daily 90 Sr intake was constant and that 18% of the infested activity was excreted in urine, the mean intake in the investigated group would vary between 27 and 96 mBq d 1 . Based on these estimated intake values the respective annual effective internal doses iron 90 Sr and 90 Y varied from 0.3 to 1.0 μSv and from 137 Cs from 4 to 350 μSv during the sampling period.

In a large village, Veprin of the Bryansk region of Russia contaminated with radionuclides as a result of the Chemobyl accident, 137 Cs concentration in food products of agricultural produce and natural origin was regularly measured, local inhabitants were polled on the composition of their diet, and the 137 Cs content in their bodies was measured at the same time. These results were used as the basis for calculation of annual effective doses of internal exposure to inhabitants and for reconstruction of the dose during the entire period after the accident (1986-1996). The efficiency of countermeasures performed for reduction of the internal dose was assessed. The internal dose in inhabitants during the 10 years after the accident was shown to be reduced by countermeasures by a factor of 2, namely down to 35 mSv instead of the expected 70 mSv. The dose of external gamma radiation during the same time period is close to the obtained dose of internal exposure. The presence of peat and water-meadow soils in the vicinity of this village that are characterised by high transfer factors for radionuclides from soil to vegetation causes a high contribution of internal exposure to the total dose of population exposure. The contribution of natural products to the internal dose increased from 6% in 1987 increased to 25% in 1996. The individual content of 137 Cs in the body of inhabitants reliably correlates with consumption of milk in the initial period after the accident and with consumption of forest mushrooms in the subsequent period.

The industrial pollution of an ecosystem, e.g., by heavy metals, might also affect the behavior of fallout radionuclides in the soils of these areas. To study such effects, we determined at various distances from the huge copper-nickel smelters at Monchegorsk on the Kola Peninsula (Russia) and at a reference site: (1) the vertical distribution of fallout 137Cs,90Sr and239+240Pu in the soil, (2) the corresponding residence half-times in different soil horizons, and (3) the resulting external gamma-dose rates at these sites in 1 m height due to 137Cs in the soil. The data show that the residence half-times and the partitioning of the fallout radionuclides among the various soil horizons depend significantly on the extent of the heavy metal pollution at the sites. The resulting external gamma-dose rate in 1 m height due to 137Cs in the soil is, however, rather similar at the various sites.

Three types of modular phantom were tested. All can be assembled to fit different geometries and to simulate different body masses. The radionuclide distribution is homogeneous in each module, but uneven distributions in the body can be simulated. The basic modular phantom consisted of flat plastic bottles filled with calibrated radionuclide solutions. An improved version was filled with a solution of plastic monomers, that was polymerised with gamma radiation to form a semi-rigid hydrogel. The third type of phantom is the 'St. Petersburg' modular block phantom, consisting of inactive tissue-equivalent plastic blocks into which rods containing known activities of the desired radionuclides are inserted. The precision of assembling the phantoms was very good for all three types. The standard deviation of the mean pulse rate was less than 2% when each phantom was measured repeatedly; the modules were removed and re-assembled between measurements. The accuracy in measuring unknown activities of 134 Cs, 137 Cs and 60 Co was 5% or better.

EDITOR, - Neither the editorial1 nor the three articles*RF 2-4* relating to the Chernobyl reactor accident make more than a passing mention to the one major increase in malignancy that has so far been identified - namely, the greatly increased incidence of childhood thyroid cancer in the exposed population of southern Belarus, which was first reported in 1992.5,6 The pathology was documented in 1993,7 the relation to the disaster has been reviewed,8 and the paradox that isotopes of iodine may be carcinogenic to the thyroid in normal children depite their safety in adults with Graves' disease has been discussed.9 As was reported at a recent World Health Organisation meeting in Rome, the increase has now also been recorded in the northern Ukraine and is continuing in Belarus. Thurstan B Brewin gives the impression that the Chernobyl accident was fairly trivial and that we know all about the dangers of radiation.10 He is concerned that the dangers of radiation are being exaggerated, but he goes too far in the direction of complacency. We most certainly do not know all about the dangers of radiation - for example, we need to know more about the tissue specific effects of different radioactive isotopes. Complacency, and a belief that we knew all about the dangers, led to huge releases of various isotopes from the Hanford nuclear facility in the United States, partly as a deliberate but covert experiment.10 Despite the accident at Chernobyl there is clearly a case to be made for nuclear power, but it must be made against a background of openness and a realistic assessment of risk. The accident at Chernobyl was unprecedented, with about 1018 Bq of radioactive isotopes released. While studies of low level exposure are valuable, studies of …

Some of the quality assurance tasks of whole-body counting are specific to that method of measurement, whereas others are similar to those of gamma spectrometric sample measurements. Quality assurance in whole-body measurement and the associated calculation of internal doses is a complex matter. The uncertainty in the measurement geometry between the radiation source and the detector is unavoidable when measuring humans. Quality assurance includes quality control with procedure and protocol descriptions, detector calibrations, instrument control, documentation of measurement results and evaluation internally or by outside persons. This evaluation also involves regularly repeated comparative measurements. An intercomparison study in the Nordic countries was carried out using a phantom that corresponded to a person weighing 62 kg. The radionuclides used were 60 Co, 137 Cs and 40 K. The phantom was circulated to seventeen laboratories. The results agreed well with the reference values. The results from this project showed that the preparedness for performing body and organ measurements in emergency situations has improved greatly since the Chernobyl reactor accident.

The deposition of 137 Cs from Chernobyl was very unevenly distributed. This resulted in big variations in foodstuffs especially those of wild origin. For estimation of internal doses groups of people were studied with whole-body counting techniques. A Helsinki group. deposition 3kBq.m -2 , was studied from 1965 onwards and groups from Viitasaari, deposition 29 kBq.m -2 , and Ammansaari, deposition 1.5 kBq.m -2 were studied from 1987 to 1994. Special items in the diet of people from Viitasaari were local freshwater fish and from Ammansaari reindeer meat. In spring 1987 the mean body burdens of the Viitasaari (10 kBq) and the Ammansaari (7.4 kBq) were 4 to 5 times that of the Helsinki group (1.9 kBq). In 1994 only 15% of the maximum mean body burden in the Viitasaari group was found. In the Helsinki and Ammansaari groups the corresponding percentage was about thirty. The great influence of the consumption of foodstuffs of wild origin was seen.

Monitoring of the workforce in the nuclear industries is carried out primarily in order to demonstrate compliance with European Union (EU) legislation and the Basic Safety Standards for the protection of the health of workers against the dangers arising from ionizing radiation recommended by the International Atomic Energy Agency (IAEA). There is, however, no common strategy for internal dose monitoring programmes currently in use in the EU countries. Surveys have been carried out in which organisations were asked to provide information on the design of their internal dose monitoring programmes and on the costs of these programmes. Information was requested from both EU countries and Associated States. Databases for storage and reporting of all gained information were constructed, and results from the surveys have been compiled. This work was carried out within the EC 5th Framework Programme project, OMINEX, which aims to provide advice and guidance on designing and implementing internal dose monitoring programmes in the workplace in such a way that best use is made of available resources, while minimising costs.

The costs of monitoring for internal exposure in the workplace are usually significantly greater than the equivalent costs for external exposure. Therefore, there is a need to ensure that resources are employed with maximum effectiveness. The EC-funded OMINEX (optimisation of monitoring for internal exposure) project is developing methods for optimising the design and implementation of internal exposure monitoring programmes. Current monitoring programmes are being critically reviewed, the major sources of uncertainty in assessed internal dose investigated, and guidance formulated on factors such as programme design, choice of method/techniques, monitoring intervals, and monitoring frequency. OMINEX will promote a common, harmonised approach to the design and implementation of internal dose monitoring programmes throughout the EU.

To study the impact of industrial pollution on the soil-to-plant uptake of fallout-radiocesium in a boreal forest ecosystem, four study sites were selected at distances of 7, 16, 21 and 28 km from the large copper-nickel smelter at Monchegorsk on the Kola Peninsula (Russia). At each site, soil and selected plant species were sampled from five plots and analysed separately for 137Cs and 40K. The data show that the root-uptake of 137Cs, as characterised by the median aggregated transfer-factor T(ag), decreased significantly (P0.05) with decreasing distance from the smelter for the plants Vaccinium myrtillus (from 0.023 to 0.007 m2 kg-1) and Empetrum nigrum (from 0.015 to 0.007 m2 kg-1), but increased for Deschampsia flexuosa (from 0.013 to 0.031 m2 kg-1). For Vaccinium vitis-idaea a significant trend for the T(ag) was not observed. The median 40K activity concentrations in these plants also decreased significantly (P0.001) with decreasing distance from the smelter for Vaccinium myrtillus (from approx. 140 to 20 Bq kg-1 dry wt.), Empetrum nigrum (from approx. 90 to 40 Bq kg-1 dry wt.), and also for Deschampsia flexuosa (from approx. 270 to 40 Bq kg-1 dry wt.). For Vaccinium vitis-idaea such a continuous significant trend was not observed. The results for the Cu-Ni polluted soils thus show: (1) that the soil-to-plant transfer of radiocesium can be significantly modified; (2) that these modifications are quite specific; and (3) that modifications of the uptake of potassium do not always correspond to those of radiocesium.

Previous ICRU reports have dealt with the formulation and properties of tissue substitutes and phantoms that are used to calibrate in vivo measurement systems. This report provides guidance on the overall process of the direct measurement of radionuclides in the human body for radiation protection and medical applications. It addresses the detectors and electronics used for the measurement; methods of background reduction and control; measurement geometries for whole body, partial body or organ counting; physical and mathematical calibration methods; data analysis; and quality assurance. It is directed to readers who need practical advice on the establishment and operation of direct measurement facilities.

Radionuclides, especially the long-lived 137Cs (physical half-life 30 years), are accumulated efficiently in the northern, subarctic, lichen-reindeer-man foodchain. Until the Chernobyl accident the fallout nuclides studied originated from nuclear weapons tests. After this accident some fresh fallout was deposited in Finnish Lapland. Lichens grow very slowly and collect nutrients very efficiently from air, rain and snow. During winter the basic fodder plants for reindeer are lichens and some winter-green plants, shrubs and dry leaves. During the bare-ground season, the reindeer eat various grasses, herbs and leaves etc. Lichens constitute 30-50 per cent of the entire vegetable mass consumed by the reindeer in a year. The highest 137Cs-concentration 2500 Bq/kg dry weight was found in lichen in the middle of the 1960s. In 1985 the concentration had decreased to about 240 Bq/kg dry weight. After the Chernobyl accident the 137Cs-concentration in lichen varied from 200 to 2000 Bq/kg dry weight in Finnish Lapland. In reindeer fodder plant samples collected in the 1980s before the Chernobyl accident the 137Cs-concentration varied from 5 to 970 Bq/kg dry weight. The highest 137Cs-concentration in reindeer meat, about 2500 Bq/kg fresh weight, was found in 1965 and thereafter decreased to about 300 Bq/kg fresh weight in the winter before the Chernobyl accident. After the accident the mean 137Cs-concentration in reindeer meat from the 1986-87 slaughtering period was 720 Bq/kg fresh weight and in 1987-88, 630 Bq/kg fresh weight.

The highly sensitive whole-body counting technique makes quantitative determinations of nanocurie amounts of gamma-emitters within the body possible. So such counters are especially suitable for the long-term measurement of tracer retention and excretion rates. In the present study, the biological half-life of body potassium in ten male volunteers was determined using 42K as tracer. The group was measured using two different types of whole-body counters. A 43-cm standard chair technique was used with counter A and a multidetector linear scanning technique with counter B. The oral tracer dose of 12-15 muCi 42K to volunteers made it possible to estimate the biological half-life of potassium, which varied from 10 to 28 days, the mean being 16 days. The total body potassium determinations were carried out with the 42K- and 40K-methods. The results of the parallel determinations performed with Counter A agreed well with those of Counter B. A good consistency was also found in the body potassium values of individual subjects, obtained using both the methods separately for each counter.

The distribution and biological half-life of 203Hg in the human body was investigated using 203Hg-labeled compounds and a regional whole-body counting technique. Fifteen volunteers were administered methylmercury as a labeled fish proteinate. A single serving of the proteinate contained an average of 1.8 uCi of 203Hg-activity and 22 mug of total mercury. Inorganic mercury was given to eight volunteers as labeled calf liver paste containing 4-8 muCi of inorganic 203Hg-activity and 6 mug of total mercury. The radiomercury determinations were performed in a steel room equipped with the standard chair geometry and one 4 inch x 8 inch NaI(Tl) crystal. For determinations of 203Hg-activity in the head a 3 inch x 3 inch NaI(Tl) crystal was used. A lead collar was utilized as a shield in order to absorb any disturbing radiation that might originate in the stomach region. The effectiveness of the Pb collar was determined using phantoms. The activities in the whole-body, the head, the legs and the liver were determined. About 20% of the methylmercury activity in the whole-body was found to be localized in the head 30 d after administration. No significant amounts of 203Hg-activity were found in the head during the first 58 d after administration of inorganic mercury. An average value of 10-15% methylmercury activity was found in the legs 30 d after administration. A control mean value of 13% was determined by measuring five of the same volunteers the next day in Sweden. Not more than 1% of inorganic mercury was found in leg muscle after 39 d in one male volunteer. The biological half-life of protein-bound inorganic mercury in the liver region, studied in one male volunteer, was estimated at 53 +/- 15 d.