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Radiation protection dosimetry, Vol. 31, Nos. 1–4, microdosimetry, proceedings of the tenth symposium on microdosimetry held at Rome (Italy) 21–26 May 1989
J. Environ. Radioactivity 18 (1993) 259-261
Book Review
Radiation Protection Dosimetry, Vol. 31, Nos. 1-4, Microdosimetry, Proceedings of the Tenth Symposium on Microdosimetry held at Rome (Italy) 21-26 May 1989. J. Booz, J. A~ Dennis and H. Menzel (eds.) ISBN 1 87098505; USDOE CONF-890517: CEC Document EUR 12864, softbound, £80. This volume contains 85 papers presented at a 1989 conference on microdosimetry. The n u m b e r a n d breadth of the papers make this proceedings a c o m p r e h e n s i v e treatise on the subject, particularly as several of the contributions are from the foremost authorities on microdosimetry. One of these is the excellent introductory, paper oil microdosimetric concepts by Dr A. M. Kellerer. Following this paper, there are six papers on radiation interactions that range from crosssections for secondary electron production through radiation interactions with biological molecules. Five papers on initial radiation effects complete the first major section on Physical Concepts (four of these papers are related to interactions with des-oxyribonucleic acid (DNA): the remaining paper is on radiation interactions with the a m i n o acid glycine). The second major section is devoted to the Development of Instruments a n d T e c h n i q u e s tbr microdosimetric measurements. There are 7 papers devoted to ion track detectors, 8 to microdosimetrv techniques, and 3 papers on techniques for determining microdosimetric averages. The last group includes an interesting c o m p a r i s o n of highpressure ionization c h a m b e r results with low-pressure proportional cotlnter results. The third section of this proceedings is on the Evaluation of Microdosimetric Quantities a n d Distributions which contains 16 papers in three groups. The first group of three papers deals with the microdosimetry of charged particle tracks and the secondary electrons generated by the passage of such particles. The second group of three papers describes the energy deposition patterns both axially a n d radially 259 J. Environ. Radioactivi O, (18)(1993)--O 1993 Elsevier Science Publishers Ltd. England. Printed in Great Britain
260
Book review
along the ionization tract. Special emphasis is placed on the dosimeiric significance of the radial energy deposition pattern. In the last group of 5 papers, the slatistics of the distributions a n d the calculation of averages are discussed. The e m p h a s i s of the firsl three sections is on f u n d a m e n t a l processes and m e a s u r e m e n t techniques. The emphasis of the remaining three sections is on application of this information to radiation biology. radiation protection a n d radiation therapy. The fourth section contains 25 papers on the application of microdosimetric m e t h o d s to radiation biology. Almost half (10) of these papers address the microdosimetry of D N A d a m a g e including the m e c h a n i s m s of p r o d u c i n g c h r o m o s o m e aberrations (breaks and incorrect recombinations). There are eight papers pertaining to radiobiological effects of ion beanas and 5 pertaining to the microdosimetry of radionuclides incorporated into the body. This section concludes with two papers on the radiobiological significance of particle ionization track structure. The fifth major section of the proceedings on microdosimet~' might be of greatest interest to the reader of JER as it pertains to applications to radiation protection. This section begins with an introductory paper by W. S. Sinclair on concepts a n d issues concerning the quality factorL the conversion factor between absorbed dose and dose equivalent. One of the topics discussed in this paper is the evidence that the Relative Biological Effectiveness (RBE) of ~'°Co g a m m a rays (1.25 MeV average energy) is only about half of that of 200 kVp X-rays. This finding helps explain some of the inconsistencies in measured values of the quality factor tbr neutrons that result from using two different low-LET reference radiations. X-rays and ~°Co g a m m a radiation. However, this finding also suggests that because X- and g a m m a - r a d i a t i o n have different quality factors, future m e a s u r i n g instruments may have to correct tot energy in order to permit accurate measurements ot 7dose equivalent e. The following paper by Harald Rossi, one of the pioneers m the field of microdosimetry, presents a concise a n d lucid discussion of the relationships between nficrodosimetric quantities a n d the radiation quality factor ~3. The next paper by t t a h n et al. proposes that the restricted linear energy transfer, dE/dx, a be used for describing the quality thctor for radiation protection purposes, but that the lineal energy, YD, also be retained for microdosimetric measurements. (Rossi's paper makes more of a case of the general use of the lineal energy, ,vD). The paper by Schmitz el al. describes the application of a tissueequivalent proportional counier to dose equivalent measurements a r o u n d accelerators and neutron generators. A second paper on applications is a joinl F r e n c h - R u s s i a n contribuiion describing dose
Book review
261
equivalent m e a s u r e m e n t s on the space station MIR. These measurements show dose equivalent rates up to 1.0 mSv hr -~ so that a 26-day mission might result in a dose of 16 mSv to the c o s m o n a u t s or astronauts. The section dealing with applied microdosimetry a n d quality factors t concludes with a G e r m a n - U . S . paper by S c h u h m a c h e r et al. on the use of a tissue-equivalent proportional counter to dose equivalent measurements for low-energy neutrons. The next three papers deal with specialized applications of microdosimetry. G r i n d b o r g et al. assess the dose distribution a r o u n d 'hot particles', highly radioactive microscopic particles associated with the fallout from the Chernobyl nuclear reactor accident in 1986 (not to be confused with the ~hot particle' problem of concern for workers in routine reactor operations). The next two papers deal with the microdosimetry of radon a n d its decay products (daughters). The first is by R. S. Caswell a n d J. J. Coyne of the U.S. National Institute of Standards a n d T e c h n o l o g y a n d the second is by Hui et al. There is a further paper by H o f m a n n et al. on a c o m p u t e r simulation of the interactions of alpha particles with digitized crosssections of lung tissues that examines whether a few "hot particles' in the lung are more h a z a r d o u s than the same activity of the radionuclide evenly distributed. This paper is consistent with previous results as it shows that, because of cell killing, the ~hot particle' is calculated to be less effective at p r o d u c i n g transformed cells (i.e., potential cancers) than a u n i f o r m distribution having the same activity. The c o n c l u d i n g six papers deal with the microdosimetry of radiation therapy and r a d i o i m m u n o therapy. This volume provides a good a n d relatively u p - t o - d a t e summary, of the status of microradiodosimetry. Although primarily suited to the experimental worker, several papers are suitable for the non-specialist who desires an insight into this field. Harold T. Peterson, Jr.
1. No w called the radiation weighting factor, w~. 2. Currently renamed the equivalent dose. 3. The reader may be confused by the misplaced footnotes on page 363. The footnote on that page goes with the term Q(L)*, immediately to the left of the footnote. The footnote that belongs to the asterisk 8 lines up from the bottom of the second colum of page 363 is on the following page, page 364. 4. The restricted linear energy transfer (LET) has a threshold or cutoff on the lowest secondary electron energy that is included in the LET calculation.
Book Review
Radiation Protection Dosimetry, Vol. 31, Nos. 1-4, Microdosimetry, Proceedings of the Tenth Symposium on Microdosimetry held at Rome (Italy) 21-26 May 1989. J. Booz, J. A~ Dennis and H. Menzel (eds.) ISBN 1 87098505; USDOE CONF-890517: CEC Document EUR 12864, softbound, £80. This volume contains 85 papers presented at a 1989 conference on microdosimetry. The n u m b e r a n d breadth of the papers make this proceedings a c o m p r e h e n s i v e treatise on the subject, particularly as several of the contributions are from the foremost authorities on microdosimetry. One of these is the excellent introductory, paper oil microdosimetric concepts by Dr A. M. Kellerer. Following this paper, there are six papers on radiation interactions that range from crosssections for secondary electron production through radiation interactions with biological molecules. Five papers on initial radiation effects complete the first major section on Physical Concepts (four of these papers are related to interactions with des-oxyribonucleic acid (DNA): the remaining paper is on radiation interactions with the a m i n o acid glycine). The second major section is devoted to the Development of Instruments a n d T e c h n i q u e s tbr microdosimetric measurements. There are 7 papers devoted to ion track detectors, 8 to microdosimetrv techniques, and 3 papers on techniques for determining microdosimetric averages. The last group includes an interesting c o m p a r i s o n of highpressure ionization c h a m b e r results with low-pressure proportional cotlnter results. The third section of this proceedings is on the Evaluation of Microdosimetric Quantities a n d Distributions which contains 16 papers in three groups. The first group of three papers deals with the microdosimetry of charged particle tracks and the secondary electrons generated by the passage of such particles. The second group of three papers describes the energy deposition patterns both axially a n d radially 259 J. Environ. Radioactivi O, (18)(1993)--O 1993 Elsevier Science Publishers Ltd. England. Printed in Great Britain
260
Book review
along the ionization tract. Special emphasis is placed on the dosimeiric significance of the radial energy deposition pattern. In the last group of 5 papers, the slatistics of the distributions a n d the calculation of averages are discussed. The e m p h a s i s of the firsl three sections is on f u n d a m e n t a l processes and m e a s u r e m e n t techniques. The emphasis of the remaining three sections is on application of this information to radiation biology. radiation protection a n d radiation therapy. The fourth section contains 25 papers on the application of microdosimetric m e t h o d s to radiation biology. Almost half (10) of these papers address the microdosimetry of D N A d a m a g e including the m e c h a n i s m s of p r o d u c i n g c h r o m o s o m e aberrations (breaks and incorrect recombinations). There are eight papers pertaining to radiobiological effects of ion beanas and 5 pertaining to the microdosimetry of radionuclides incorporated into the body. This section concludes with two papers on the radiobiological significance of particle ionization track structure. The fifth major section of the proceedings on microdosimet~' might be of greatest interest to the reader of JER as it pertains to applications to radiation protection. This section begins with an introductory paper by W. S. Sinclair on concepts a n d issues concerning the quality factorL the conversion factor between absorbed dose and dose equivalent. One of the topics discussed in this paper is the evidence that the Relative Biological Effectiveness (RBE) of ~'°Co g a m m a rays (1.25 MeV average energy) is only about half of that of 200 kVp X-rays. This finding helps explain some of the inconsistencies in measured values of the quality factor tbr neutrons that result from using two different low-LET reference radiations. X-rays and ~°Co g a m m a radiation. However, this finding also suggests that because X- and g a m m a - r a d i a t i o n have different quality factors, future m e a s u r i n g instruments may have to correct tot energy in order to permit accurate measurements ot 7dose equivalent e. The following paper by Harald Rossi, one of the pioneers m the field of microdosimetry, presents a concise a n d lucid discussion of the relationships between nficrodosimetric quantities a n d the radiation quality factor ~3. The next paper by t t a h n et al. proposes that the restricted linear energy transfer, dE/dx, a be used for describing the quality thctor for radiation protection purposes, but that the lineal energy, YD, also be retained for microdosimetric measurements. (Rossi's paper makes more of a case of the general use of the lineal energy, ,vD). The paper by Schmitz el al. describes the application of a tissueequivalent proportional counier to dose equivalent measurements a r o u n d accelerators and neutron generators. A second paper on applications is a joinl F r e n c h - R u s s i a n contribuiion describing dose
Book review
261
equivalent m e a s u r e m e n t s on the space station MIR. These measurements show dose equivalent rates up to 1.0 mSv hr -~ so that a 26-day mission might result in a dose of 16 mSv to the c o s m o n a u t s or astronauts. The section dealing with applied microdosimetry a n d quality factors t concludes with a G e r m a n - U . S . paper by S c h u h m a c h e r et al. on the use of a tissue-equivalent proportional counter to dose equivalent measurements for low-energy neutrons. The next three papers deal with specialized applications of microdosimetry. G r i n d b o r g et al. assess the dose distribution a r o u n d 'hot particles', highly radioactive microscopic particles associated with the fallout from the Chernobyl nuclear reactor accident in 1986 (not to be confused with the ~hot particle' problem of concern for workers in routine reactor operations). The next two papers deal with the microdosimetry of radon a n d its decay products (daughters). The first is by R. S. Caswell a n d J. J. Coyne of the U.S. National Institute of Standards a n d T e c h n o l o g y a n d the second is by Hui et al. There is a further paper by H o f m a n n et al. on a c o m p u t e r simulation of the interactions of alpha particles with digitized crosssections of lung tissues that examines whether a few "hot particles' in the lung are more h a z a r d o u s than the same activity of the radionuclide evenly distributed. This paper is consistent with previous results as it shows that, because of cell killing, the ~hot particle' is calculated to be less effective at p r o d u c i n g transformed cells (i.e., potential cancers) than a u n i f o r m distribution having the same activity. The c o n c l u d i n g six papers deal with the microdosimetry of radiation therapy and r a d i o i m m u n o therapy. This volume provides a good a n d relatively u p - t o - d a t e summary, of the status of microradiodosimetry. Although primarily suited to the experimental worker, several papers are suitable for the non-specialist who desires an insight into this field. Harold T. Peterson, Jr.
1. No w called the radiation weighting factor, w~. 2. Currently renamed the equivalent dose. 3. The reader may be confused by the misplaced footnotes on page 363. The footnote on that page goes with the term Q(L)*, immediately to the left of the footnote. The footnote that belongs to the asterisk 8 lines up from the bottom of the second colum of page 363 is on the following page, page 364. 4. The restricted linear energy transfer (LET) has a threshold or cutoff on the lowest secondary electron energy that is included in the LET calculation.