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Asker Aarkrog E Risø-R-437 Part II (Appendices Environmental Studies on Radioecological Sensitivity and Variability with Special Emphasis on the Fallout Nuclides *°Sr and ,37Cs Asker Aarkrog Risø National Laboratory, DK-4000 Roskilde, Denmark June 1979 RISØ-R-437 ENVIRONMENTAL STUDIES ON RADIOECOLOGICAL SENSITIVITY AND VARIABILITY WITH SPECIAL EMPHASIS ON THE FALLOUT NUCLIDES 90sr and 137C. Part two Appendices by Asker Aarkrog Risø National Laboratory Health Physic* Department June 1979 Risø National Laboratory, DK 4000 Roskilde, Denmark ISBN 87-550-0736-8 ISBN 87-550-0727-9 ISSN 0106-2840 Risø Repro 1981 - 271 - Page CONTENTS OF PART TWO APPENDICES APPENDIX A SAMPLING, ANALYSIS, MEASUREMENT AND ERROR 275 A.l. Sampling methods 275 A.2. Analytical procedures and measurements of radioactivity 313 A.2.1. Radiostrontium analysis 314 A.2.2. Plutonium analysis 314 A.2.3. Assessment of radiocesium 316 A.2.4. Radioactivity measurements 317 A.3. Quality of data assessment 321 A.3.1. The precision of the data 322 A.3.2. The accuracy of the data 325 APPENDIX B ANALYSIS OP VARIANCE, AND THE VARIABILITY 328 B.l. Introduction 328 B.2. Seme statistical definitions 328 B.3. Analysis of variance 331 B.4. Variability 335 B.5. Anova and variability tables 337 APPENDIX C PREDICTION MODELS AND RADI0EC0LOGICAL SENSITIVITY 361 C.l. Introduction 361 C.2. Actual models 362 C.3. Radioecological sensitivity 364 C.4. FIT-tab les 365 APPENDIX D NOTES TO THE MAIN TEXT 399 D.1.2. Summary of history of nuclear weapons testing 399 D.1.2.1. Local variations in the con- 90 137 centrations of Sr and Cs in air samples 400 90 Table D.1.2.1. Total deposition of Sr in the northern hemisphere related to 90 137 Sr and " Cs concentrations in ground-level air at Risø • • • 401 - J.: i z - Page 90 Table D.l.3.2. Earlier estimates of the Sr deposition in Denmark before Danish measurements began 402 D.1.3.3. Calculation of the fallout-weighted mean precipitation at the state experimental farms 402 90 D.1.4.1. An estimate of the transfer of Sr from Danish ground water to the biosphere 403 90 D.l.4.2. Estimate of Sr run-off with Danish streams 404 Table D.1.5.1. The 90Sr and 137Cs con­ centrations in Danish waters related to salinity 405 Table D.1.5.2. Strontium-90 in deep sea water collected by the Dana in the North Atlantic 406 D. 1.6.1.1. Removal processes for radio­ nuclides deposited en the surface of the earth 406 90 Table D.1.6.1.1. An estimate of the total Sr 137 and Cs uptake by Danish crops 1950-1974 408 Table D.1.6.1.2. Strontium-90 and Cs in Greenlandic and Faroese soils 410 D.l.6.2. Estimate of the effective halflife 90 of Sr in Danish soils 410 Table D.1.6.2.1. Calculated effective halflives for the root uptake of 90 Sr from uncultivated soils 411 Table D.l.6.2.2. Calculated effective halflives fcr the root uptake of 90 Sr from cultivated soils 414 Table D.1.5.2.3. Calcium and stable strontium ir. the coil of the ploughing layer collected from 10 Danish experime.it«! farms in 19f»6 415 - 273 - Page D.2.2.1. Influence of variety on radionuclide concentrations is cereal grain 415 D.2.2.2.1. Comparison between prediction models for pCi 90S r (g Ca)- 1 in cereal grain. 417 D.2.2.2.2. Error estimate of prediction models for grain 418 D.2.4.1. The calcium and potassium content of Danish, Faroese and Greenlandic grass samples 419 Table D.3.2.1. Peed units in various crops re­ lative to feed units from grass 420 D.3.4.4. On the fallout rate used in the pre­ diction models for sataples from Nest Greenland 420 D.3.5.1. Calcium content of cod-flesh 421 D.4.2.1. The importance of the variations in the composition of the Danish total diet .. 421 D.4.2.2. Assessment of the radioactive contami­ nation of the Danish total diet 424 Table D.4.2.2. A comparison of the relative con­ tributions from the various diet groups and of the transfer coefficients P-3 .. 426 D.4.3.2. Prediction models based on diet levels for 90S r in adult human bone 426 D.4.4.1. Influence of the time of tooth sampling "* on the 90S r concentrations observed in shed deciduous teeth 428 D.4.7.7. The collective 'effective dose equivalent commitibwnt , .. 428 D.4.7.8. The significance of the time distri­ bution of the fallout when applied for calculation of the radioecological sen­ sitivity 429 0,5.2.1. Statistical information on Danish agricultural produce with estimates of calcium and potassium levels 430 ABBREVIATIONS AND UNITS 435 APPENDED REPRINTS 437 - 275 - APPENDIX A SAMPLING, ANALYSIS, MEASUREMENT AND ERROR This appendix comprises sunmariss of sampling Methods and analytical procedures including counting and an assessment of the lover Unit of detection. The appendix is concluded by an estimate of the precision and accuracy of the data. A.l. Sampling methods To estimate a variable in a population (cf.B.2.), it is usually impossible to measure the whole population. Instead, a sample must be taken, i.e. a number of individuals are selected from the population and measured. This selection should be made so as to obtain a truly representative sample of the population, which is best done by random selection. In the present study, the various sample locations and sampling intervals were selected beforehand with a view to being representative of the area studied with respect to food production, rainfall and soil characteristics, and to ensure that seasonal and yearly variations were taken into account. Once these locations and sampling intervals had been determined, sampling was carried out randomly. The present sampling programme was designed for a study of the environmental radioactive contamination from global fallout in Denmark, the Faroes and Greenland. As both population and food production were concentrated in Denmark (5 * 10 inhabi­ tants), most samples were collected there. On the other hand, Greenland (S • 10 inhabitants) and the Faroes (4 • 10 inhabi­ tants) were not neglected because the special environmental conditions and dietary habits in these territories can enhance the dietary intakes of radionuclides by the local populations; in other words, the radioecological sensitivity of humans may be higher in the Faroes and Greenland than in Denmark. Sampling in the Faroes and Greenland was carried out with the help of doctors, pharmacists, and staff at telestations and meteoro­ logical stations. However, it was not always possible to obtain all samples specified in .the programmes because communications, especially with remote locations in Greenland, were poor. The Danish sampling programme was intended to yield data on the radioactive contamination of the various foods both where they were produced and at the site of consumption. The production levels were estimated from two main sampling systems: the seven dried milk factories (Fig.A.1.3.2), which yielded an estimate of the radionuclide levels in Danish milk products, and the eleven state experimental farms (Fig.A.1.1.3.1 and table A.1.1.6.2) from where samples of precipitation, soil, gra*n, potatoes, milk and fodder were-obtained. The sampling system for the consumption site consisted of the 48 provincial towns (1.14 • 106 inhabitants) in the 8 zones (Figs. A.1.4.2.1 and A. 1.4.2.2) and Copenhagen (1.35 * 10 inhabitants). The samples from this system were purchased in local stores and consisted of all diet components, besides simultaneous collection of individual samples of bread, dairy milk and vegetables. The sampling methods that were applied in the present study are summarized below in the tables denoted A.l. followed by two digit? identical to the numbering in the main text of the sample category in question. The sampling locations are shown in corresponding figures. Hore detailed information on sampling methods appears in the Ris# Reports referred to in the table heads of the various samples. Sampling principles for assessment of radioactive contamination in the environment have, moreover, been dealt with in several publications (Harl72, H666, Ka7tf). - 277 - T»»l« A.l.1.2. Saaplin* of *ir Small M^ltr (He 54-57) Larea saapler (MIO CO) mom* Hf et peper filters 2 rectangular olass fibre filtors. S« x 4« c«2 each SIM 300-400 n3 day"1 3*000 m"3 day-1 Locality Ms* Ris« 3 m aeowo the eround 3 • above tho ground NrM Sine* 1»S« Sine* IMO Frequency Continuous op«ration Continuous operation daily saaøles half-weekly samples Roel MM "sr eMSr) *°Sr C*'sr), Y-eaitters •specially 137Cs Pooling The daily Maples for Radlostrontlum on before 1 Month ara coefelned Monthly aliquot*. analysis Y on half-weakly total saaplas Reeerks niter efficiency Filter efficiency - 100% ~ lOOt 278 - T»bU ».1.1.1.1. Saall ram Ion aachane* 1 • eaaa>ler Neteoroloay state eap. bottlaa eoliarna (MM • 3) tower fame (MM * 1) (MM I 2) (•a 54-57) (MM M 4) istrr) (MD 401 (MS il. DUO ti) (UO 541 (WD 42) Mathod Elaht rtva a. q ladratle tlalit Thra« polyathylana Ion aachanf« atalnlaaa polyethylene polyathylan« bottlaa »tth colama wit« ataal bettlee at bottlaa at polyathyalena polyethylan* eaavler dlffarant aach atatlon funnala fannala helvhta In tha with »tea Dovex SO a ft 121 n tower funnala Oowm 2 a • Siw taaplln« tMBllnf I.2 lach bottle Saaellna araa of tha araa of the had a funnal araa of th« t bottlaa.
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