Davis and Repatriation Commission - [2000] AATA 364

DECISION AND REASONS FOR DECISION [2000] AATA 364

ADMINISTRATIVE APPEALS TRIBUNAL )

) No N1997/276

VETERANS' APPEALS DIVISION )

Re Peter Jerome DAVIS
Applicant

And REPATRIATION COMMISSION
Respondent

DECISION

Tribunal Mrs M T Lewis, Senior Member Dr M E C Thorpe, Member Dr P D Lynch, Member

Date10 May 2000
PlaceSydney

Decision The Tribunal sets aside the decision under review, being a decision of a delegate of the Repatriation Commission ("the Respondent") dated 23 February 1996 which refused a claim made by Peter Jerome Davis in respect of myelodysplastic syndrome, and in substitution therefore the Tribunal decides that the condition myelodysplastic syndrome is a war-caused disease with effect on and from 9 November 1995. The Tribunal remits the matter to the Respondent to assess the rate of pension payable.

..............................................
M T Lewis
Presiding Member
CATCHWORDS
VETERANS' AFFAIRS- disability pension – entitlement - whether myelodysplastic syndrome caused by operational service - whether exposed to ionising radiation from Hiroshima atomic bomb blast – whether suffered from external residual gamma radiation exposure in Hiroshima – whether external gamma radiation resulted in significant radiation exposure – whether hypothesis linking exposure to internal radiation with myelodysplastic syndrome reasonable – whether condition due to ingestion or inhalation of radioactive isotopes - whether internal radiation hypothesis contrary to scientific fact - no Statement of Principles - whether Statement of Principles regarding similar medical condition applied – whether any exposure to benzene at work in 1985 and 1991 disproved reasonable hypothesis

Veterans' Entitlements Act 1986 (Cth) –ss 120(1), 120(3), 120A(4)

Re Estate of Redenbach and Repatriation Commission (1990) 21 ALD 738
Re Repatriation Commission and Thorne (1989) 17 ALD 251
Re Hill and Repatriation Commission (AAT 7535, 11 October 1991)
Re Byrnes and Repatriation Commission (1993) 177 CLR 564
East v Repatriation Commission (1987) 16 FCR 517

REASONS FOR DECISION

10 May 2000 Mrs M T Lewis, Senior Member
Dr M E C Thorpe, Member Dr P D Lynch, Member

This is a review of a decision of a delegate of the Repatriation Commission ("the Respondent") dated 23 February 1996 which refused a claim made by Peter Jerome Davis ("the Applicant") in respect of myelodysplastic syndrome. That decision was affirmed by the Veterans' Review Board ("the VRB") on 18 December 1996. The Applicant lodged an application for review by this Tribunal on 10 March 1997. All applications for review were in time, and therefore the earliest effective date is 9 November 1995, being not more than three months before lodgement of the claim for acceptance of the condition.
The Tribunal had before it the documents produced by the Respondent pursuant to s 37 of the Administrative Appeals Tribunal Act 1975. The following documents were tendered as evidence on behalf of the Applicant –

Report of Professor John Mathews dated 9 November 1998 with curriculum vitae (exhibit A) and supplementary report dated 23 March 1999 (exhibit M)
Report of Dr Josephine Wiseman dated 15 March 1998 (exhibit B)
Report of Dr Robert Cumming dated 18 July 1997 (exhibit C)
Copy of letter from Respondent to Applicant dated 5 December 1973 (exhibit D)
Report of Dr Warwick Benson dated 21 July 1988 (exhibit E)
Report of Dr R D Puflett dated 5 December 1988 (exhibit F)
Report of Dr D E Joshua dated 9 February 1989 (exhibit G)
Collection of photographs of atomic bombings of Hiroshima and Nagasaki (exhibit H)
Two maps of Hiroshima area (exhibit J)
US – Japan Joint Reassessment of Atomic Bomb Radiation Dosimetry in Hiroshima and Nagasaki, Roesch, W.C (Ed) – Chapter 6 – Radiation Doses From Residual Radioactivity by Okajima et al (exhibit K)
Extracts from Hiroshima and Nagasaki. The Physical, Medical, and Social Effects of the Atomic Bombings. Report of the Committee for the Compilation of materials on Damage Caused by the Atomic Bombs in Hiroshima and Nagasaki, Ishikawa, E & Swain,D.L (exhibit L)
Supplementary Report of Professor J Mathews dated 23 March 1999 ( exhibit M)
Article by Shizuma et al entitled 137 Cs Concentration in soil samples from an early survey of Hiroshima Atomic Bomb and Cumulative Dose Estimation from the Fallout in Health Physics (September 1996, V71, No 3) (exhibit N)

Medical report of Dr Ilbery dated 23 August 1997 with attachments (exhibit 1) was tendered on behalf of the Respondent. Dr Ilbery provided a supplementary report dated 16 July 1999 (exhibit 2), after the conclusion of the hearing, with the agreement of the parties.
Dr Wiseman is a physician in nuclear medicine and she practices in the area of the treatment of persons suffering from cancer. She gave oral evidence at the hearing. Professor Mathews is an epidemiologist, with particular interest in Aboriginal health and tropical health issues. He was called by the Applicant to give evidence. He has a continuing research interest in the relationship of radiation to disease, and is a director of the Menzies School of Health Research in Darwin. Dr Ilbery, RFD, MD, FRACR, holds qualifications in diagnostic radiology and therapeutic radiology, and is a consultant to the Department of Veteran's Affairs. He was called by the Respondent to give evidence. He was previously an Associate Professor in Radiobiology at University of Sydney where he conducted a radio-biology research unit. More recently he was the Medical Director of the Cancer Institute in Melbourne. He has been a member of a review committee of the Australian Atomic Energy Commission.
Professor Mathews and Dr Ilbery both gave evidence simultaneously by video conference, which provided the opportunity for each to comment on the other's evidence. The Tribunal considers that this process assisted it in understanding and clarifying the very technical evidence which they gave, and in particular to clarify the areas of agreement between these two eminent specialists and the issues on which they disagreed.
The Applicant served in the Royal Australian Navy in World War 2 from 19 April 1945 to 11 February 1947, including operational service. His claim falls for determination pursuant to ss 120(1) and (3) of the Veterans' Entitlements Act 1986 ("the Act"), and as the claim was lodged after 1 June 1994 s 120A applies. However, as no Statement of Principles has been determined, and as no notification has been given that the Repatriation Medical Authority proposes to make such a Statement of Principles in respect of myelodysplastic syndrome, pursuant to s 120A(4), s120A(3), which requires that a Statement of Principles upholds the hypothesis, does not apply. Subsections 120(1) and (3) provide –
(1)Where a claim under Part II for a pension in respect of the incapacity from injury or disease of a veteran, or of the death of a veteran, relates to the operational service rendered by the veteran, the Commission shall determine that the injury was a war-caused injury, that the disease was a war-caused disease or that the death of the veteran was war-caused, as the case may be, unless it is satisfied, beyond reasonable doubt, that there is no sufficient ground for making that determination.
(2)…..
(3)In applying subsection (1) or (2) in respect of the incapacity of a person from injury or disease, or in respect of the death of a person, related to service rendered by the person, the Commission shall be satisfied, beyond reasonable doubt, that there is no sufficient ground for determining:
(a)that the injury was a war-caused injury ….;
(b)that the disease was a war-caused disease ….; or
(c)…..
as the case may be, if the Commission, after consideration of the whole of the material before it, is of the opinion that the material before it does not raise a reasonable hypothesis connecting the injury, disease … with the circumstances of the particular service rendered by the person.
The Applicant gave oral evidence at the hearing. He was born on 6 May 1927. His evidence was that he visited the Hiroshima bomb site approximately 8 months after the explosion, during his service on HMAS Manoora which was in Kure Harbour, having conveyed the first Australian Occupational Force to Japan in March/April 1946. The duration of his visit was for 8 hours on the first day and for about 4 hours the next day. He was then aged 18 years. There was no dispute that the Applicant visited the bomb site as described in his evidence, and the Tribunal so finds.
Despite being rather vague in his evidence, the Applicant identified the location of his visit in the photographs of the remains of the Sei hospital (exhibit L), which was very close to the epicentre. He also recognised the photograph (figure 25 in exhibit H) as the area in which he spent several hours fossicking in the rubble. He said that during his visit he would have walked less than two miles on flat terrain. He recalled the weather being still and dry.
The Applicant's evidence was that whilst visiting the bomb site he drank local water from a tap near the railway line and ate local food which he had exchanged for cigarettes. When he returned to the ship after fossicking in the rubble for several hours he said that he was covered in dust and dirt, and his fellow servicemen commented on how dirty he was. He said "I had lumps like bits of coal in the corner of my eyes. I had it on my teeth and mouth, and around my ears were particularly black".
The Applicant recalled finding a molten glass and metal ball whilst fossicking, which he took back to the ship and put it in his hammock. He slept with the ball in his hammock and took it home with him when he returned to Sydney. When he returned to sea he took it with him and again kept it in his hammock, and subsequently he threw it into the sea before returning to Sydney as his mother did not like him having it.
Dr A Manoharan, a Staff Physician in Clinical Haematology at St George Hospital, diagnosed the Applicant to be suffering from myelodysplastic syndrome in April 1985 (T5, p28). There is no dispute between the parties as to the diagnosis. Dr Manoharan described the condition as a "haemopoietic stem cell qualitative problem which carries a 25 percent risk of transforming into a leukaemic state". It was the Applicant's evidence that his condition is stable. As there is no evidence before the Tribunal that his condition has progressed to a leukaemic state the Statement of Principles in respect of leukaemia do not apply in this case.
Dr Joshua, Haematologist at Royal Prince Alfred Hospital, in his report dated 9 February 1989 (exhibit G), considered it possible that the Applicant's myelodysplastic syndrome had been present since 1982. An episode of epistaxis in 1981 or 1982 was possibly the initial presentation. On the basis of this evidence the Tribunal finds that a period of at least 35 years had elapsed from the time of the Applicant's visit to Hiroshima and the clinical onset of myelodysplastic syndrome.
Professor Mathews provided an hypothesis associating the Applicant's myelodysplastic syndrome with his visit to Hiroshima in the following terms (exhibit A) –
The Hiroshima bomb would have yielded about 4-8x1013 Bq of Sr90,…. he would have needed to absorb about 1.7/104 ug (an invisible speck) which could have contained in 100 ug of soil from the heavy fallout area. It is not inconceivable that this amount of Sr90 could have been absorbed through contaminated food or water or even through inhalation of radioactive dust or through absorption of a speck through a skin abrasion.
If Mr Davis had absorbed such an amount, this would have lodged primarily in bone, with a biological half-life of 15 years, and delivered an aggregate dose equivalent of 32rem (320 mSv) to the bone marrow over the 50 years since the material was absorbed (NCRP. 1980. Management of Persons Accidentally Contaminated with Radionuclides. NCRP Report No 65. National Council on Radiation Protection, Washington.) Such a dose could have made a major contribution to the development of [myelodysplastic syndrome] in Mr Davis. [Myelodysplastic syndrome] is due to failure of stem cells in the bone marrow to regenerate blood components normally.
In his oral evidence Professor Mathews expanded his hypothesis in the following way –
The only way that [Mr Davis] could have been exposed to a very significant amount of radiation would be if he carried some of the radiation away with him, and the two ways in which that might have happened would be if the souvenir Mr Davis described was highly radioactive and we have no direct evidence that that might be the case so I haven't pursued that further. The other way that he may have carried a significant radiation dose away with him would have been if he had absorbed radio-nucleis while he was at Hiroshima for that relatively short period of time and what I've done is just to look at the plausibility of that happening, the plausibility of there being a sufficient absorption of radio-nuclei during a brief visit that might have had a significant dose equivalent effect on Mr Davis subsequently. And we don't know of course precisely that that happened, but I've looked at it as the only way that I can eagerly (sic) [easily] see that a significant dose of radiation would have resulted.
Dr Wiseman criticised the VRB for presuming that the degree of radiation from the glass and metal souvenir would not have been higher than the general site radiation. She noted that it was in close contact with the Applicant's body over a period of many months. She said –
As a result of the inverse square law, radiation from objects in close proximity to body would be an order of magnitude higher than exposure from an object at, say, 1 metre's distance.
Both Professor Mathews and Dr Ilbery in their oral evidence agreed that the glass souvenir was not a significant irradiating item. In light of this and the lack of submissions about it by the Applicant at the conclusion of the hearing, the Tribunal does not propose to deal with it as a raised hypothesis given the other hypotheses that received much more attention.
was the raised hypothesis reasonable?
The Tribunal was referred by Dr Ilbery (exhibit 1) to Harrisons' Text Book of Medicine in which the median age of presentation of myelodysplastic syndrome is 70 to 80 years. Cecil and Loeb Text Book of Medicine (20th edition) gives 68 as the mean age of onset, with a slightly higher incidence in males (p.836). The Applicant was aged 53 or 54 years at the time of onset, which the Tribunal accepts to be about 1982. The aetiology of myelodysplastic syndrome was discussed by Dr Ilbery in his report (exhibit 1). He noted that although the aetiology is unclear, some patients appear to develop myelodysplastic syndrome secondary to chemotherapy, particularly alkylating agents, with or without accompanying radiation therapy, while radiotherapy alone is of doubtful significance. However Dr Ilbery noted that another author states that myelodysplastic syndrome induced by radiotherapy alone is an unusual but recognised event.
Radiation Exposure
In considering the question of radiation exposure the Tribunal had before it an article by Kiyoshi Shizuma supplied by Professor Mathews after the conclusion of his evidence on which Dr Ilbery commented in a subsequent report (exhibit 2) by agreement with the parties. The article by Okajima (exhibit K) and extracts from the Report of the Committee for the Compilation of Materials on Damage Caused by the Atomic Bombs in Hiroshima and Nagasaki (exhibit L) also go to this issue. The Tribunal notes that these publications focused on external gamma radiation. The lack of precise data, the large range of measurements quoted and the numerous assumptions made in each of these sources did little to inspire confidence in the Tribunal about the existence of a firm scientific foundation about the level of radiation exposure to the Applicant as a result of his visit to the bomb site. Additionally, the numerous and varied units of measurement in the literature makes comparisons difficult to consider. Consequently, the Tribunal was heavily reliant on the expert evidence of Dr Ilbery and Professor Mathews, and to some extent, Dr Wiseman, who was less qualified to speak about the physics of atomic explosions, and whose evidence gave the impression of being more of an advocate than an expert witness.
There are three separate phases to the hypothesis in the assessment of the radiation to which the Applicant was exposed – drinking local water, eating local food, and being covered in dust from the bomb site. These will be considered separately.
On the basis of the Applicant's evidence about the details of his visit to the bomb site, the Tribunal assumes that at no stage did the Applicant enter the high fallout area of Koi Takasu, two kilometres west of Koi station, some 2½ miles from the epicentre and in hilly country (exhibit J and exhibit K fig.1). Therefore the Tribunal finds that the Applicant would not have been exposed to a higher than average level of external residual gamma radiation during his visit to Hiroshima.
External Radiation from the Bomb Site
The evidence before the Tribunal was very technical. The Tribunal's understanding of the evidence is that the external radiation from the bomb site was massive at the time of the explosion (initial radiation) and it consisted of alpha, beta and gamma rays, plus the obvious physical, thermal and ultraviolet radiations. Although the initial radiation was massive it fell off rapidly and declined to an insignificant level within weeks. Therefore, eight months after the explosion, any gamma radiation other than background radiation, which could have had any effect on the Applicant, would have been from residual radiation.
External radiation subsequent to the explosion was mostly gamma radiation, which is the process by which all radioactive substances decay. The residual radiation was created in two ways; gamma rays (and some neutrons) from radioisotopes created by the atomic explosion, which were dispersed at the time of the explosion either directly or as fallout, and neutrons from the explosion, which bombarded non-radioactive soil, water and buildings in Hiroshima near the epicentre and made them radioactive (induced radiation). Dr Ilbery's evidence was that the neutron induced residual radiation occurred mainly within one kilometre of the epicentre (exhibit 1). The Tribunal finds that therefore the neutron induced radiation could be significant in the area in which the Applicant fossicked.
The radioisotopes delivered by the blast and fallout would be likely to deposit isotopes away from the epicentre. The physical effect of the blast at the ground level tended to deposit its load of radioisotopes around the periphery of the epicentre. This is pertinent to the consideration of the radioactive contamination in the area in which the Applicant wandered. In contrast, the fallout, which constitutes the majority of the nuclear pollution from the bomb, would tend to drop its load a long way from the epicentre, but this is affected by climatic condition. This is a complex issue as many different forces were operating. However, the issue of the distribution of isotopes from the bomb has been resolved to a large extent by the analysis of soil samples by Shizuma et al (exhibit M). The Tribunal accepts their conclusion that the average uniform concentration of Cesium 137 was 0.31mC/kg for an area within 5 kilometres from the epicentre, except for the heavy fallout area at Koi-Takasu which was 1.0 mSv/kg.
The average level of all the residual external radiation attenuated rapidly. It has been estimated (exhibit L, p78) that Strontium 90 (Sr90) and Cesium 137 (Cs 137), plus some 200 other radioactive isotopes, were scattered in an averaged level somewhat uniformly over the whole area of Hiroshima. This induced radiation decreased with the half-life specific for each isotope and as the majority of the isotopes have a short half-life the intensity of radioactivity as a whole attenuates rapidly. The actual measurement reflects an average of the radiation from all the estimated 200 different isotopes. The attenuation is the result of the short half-life isotopes decaying rapidly and leaving the long half-life isotopes producing the majority of the residual radiation. The initial external gamma radiation levels were high, with a maximum 4 - 44 Rad 1hr after the explosion, which also attenuated with distance from the epicentre (exhibit L, p72) as well as time (exhibit K, p206). This suggests that one month after the bomb blast at Hiroshima the maximum levels would have reduced from 5.7 Rad to 1.3 Rad. These are noted to be very rough estimates and maximum levels. The majority of the isotopes have short half-life. However some of the isotopes, such as Sr90 and Cs137, are long half-life substances. They can be present for years and as they decay they continue to give off low levels of gamma radiation and, in the case of strontium, the additional production of beta rays.

There was general agreement between Professor Mathews and Dr Ilbery that external gamma radiation was of no significance in assessing the radiation hazard suffered by the Applicant. This was best illustrated by Professor Mathews' oral evidence –
… I have used Strontium 90 as a talking point because the only way Mr Davis could have had a significant radiation exposure as a result of a fairly short visit to Hiroshima would have been if he absorbed some particle of long lived radiolei. Strontium 90 is the prototype one. He could also have absorbed Cesium and some other nuclei, but as I have mentioned, the biological half-life, the time that those radionuclei like Cesium would stay in the body, is only about 100 days, so (sic) the biological half-life of Strontium is 15 years." (Transcript 1, p26)
Dr Ilbery estimated that the Applicant received a dose of 1 mSv, which is only half the normal background radiation we each receive annually. Professor Matthews commented (exhibit A) that "If this estimate is accurate there would be a negligible contribution to MDS (1 mSv represents only 1-2% of the total radiation dose during Mr Davis' life-time"). Dr Wiseman considered 1 mSv to be an increased risk of 1.5% (exhibit B). However, in her oral evidence in answer to a question about the risk of ingested versus induced radiation she said in effect that there was more risk to the Applicant from ingested radiation because by the time he was in Hiroshima the external irradiation had diminished.
Having considered all the evidence regarding external radiation, and giving greater weight to the evidence of Professor Mathews and Dr Ilbery, the Tribunal finds that external gamma radiation was not a cause of any significant radiation exposure to the Applicant at the time of his visit, or subsequently from his prolonged contact with the glass sphere.
Internal Radiation from Absorbed Radioisotopes
Professor Mathews was of the view that internal radiation was the only way the Applicant could have absorbed significant radiation in such a short visit to Hiroshima eight months after the explosion. In his report (exhibit A) he states that Dr Ilbery's calculation of a 1 mSv dose of radiation exposure "… does not appear to allow for the possibility of radionuclide absorption through the skin, or through inhalation; or through ingestion of water and food". In his oral evidence Dr Ilbery was reluctant to consider this hypothesis as he said there were no scientific facts to support such a proposition and he opined that the whole matter of internal ingestion was "speculative".
The hypothesis is now restricted to internal radiation and its causal connection to the absorption of residual nuclides, such as Sr90, into the body and the subsequent low-dose long-duration radiation with short range but destructive alpha, beta and less significant gamma rays. The hypothesis is that these long half-life radioisotopes were in the soil and water, and could have been ingested as dust through the eyes and upper airways to the alimentary tract and gained entry into the bloodstream. In the case of Sr90, which behaves in the same way as calcium in vivo and therefore lodges in the bones, it is ideally placed to irradiate the bone marrow. The half-life of Sr90 reduces from 28-29 years in the soil to 15 years in the body, because of Calcium metabolism and excretion. Sr90 emits beta rays, which are more damaging than gamma rays and can damage the genetic material (DNA) of the rapidly dividing blood-forming cells. The hypothesis is that, in the long term, this can produce diseases such myelodysplastic syndrome.
The Applicant's evidence was that he drank water from a tap near the railway line and he ate at least one meal prepared by the local people. This raised the possibility of ingestion of radionuclide but only those of long half-life such as Sr90 and Cs 138 would be significant. Cs 138 has been measured in the soil samples at the Hiroshima bomb site. The Tribunal is required to consider whether it is plausible that the Applicant could have ingested radioactive material.
Additionally, the Applicant's evidence was that he was covered in dust from fossicking – it was in his eyes and his hair, and on his hands and his uniform. He made no mention of any cuts or scratches. The other possible portal suggested for the absorption of nuclides were via the Applicant's lungs by inhalation and from his eyes and nose to his throat and by involuntary swallowing to reach his gut and be taken into the bloodstream. The Tribunal finds that this is a plausible mechanism for the entry of radionuclide into the Applicant's alimentary tract and lungs. The hypothesis however is not supported by documented facts. There is no documentation of Sr90 measurements in the soil of Hiroshima, Nagasaki or in the United States Nuclear tests.
Professor Mathews considered the possibility that the Applicant was exposed to and absorbed a minute amount of Sr90 (exhibit A). He noted that, using the report of UNSCEAR entitled "Ionizing Radiation: Sources and Biological Effects" (United Nations, New York, 1982) a total yield for the bomb would have been 4-8 Bq x10 13 of Sr90 and 6-12 Bq of Cs 137. He acknowledged that Dr Ilbery correctly argued that this was mainly dispersed in the atmosphere rather than being deposited near the hypocentre. This atmospheric pollution returns to the earth's surface as fallout. There was some fallout in less than half the area in which the Applicant wandered. This may have raised the epicentre residual radiation levels but they would have been no higher than the average levels of the whole area. Professor Mathews acknowledged that there were no records of Strontium in soil samples but he suggested, quite reasonably, that they would be of similar order to those documented for Cesium, because it is known they were produced by atomic explosions. Professor Mathews appears not to have made any reduction for the lower total yield of Strontium compared with Cesium. Also, he has chosen to use the maximum levels of Cesium found at Hiroshima of 1mC/Kg (in the Koi-Takasu district which was not visited by the Applicant) rather than the more appropriate level of 0.31mC/Kg provided by Shizuma et al in the conclusion of their article from which Professor Mathews has quoted.
On the basis that Professor Mathews has over estimated on both of the initial assumptions, the Tribunal has undertaken a simple mathematical proportional recalculation which would reduce Professor Mathews' calculated figure of cumulative dose of 320 mSv multiplied by 0.31/1.0 for the Applicant's likely exposure to 99.2 mSv. The further deduction of one third for the proportional decreased total yield from the bomb of Sr90 compared with Cs137, recalculated, would produce a figure of 66mSv for the cumulative lifetime dose over 50 years. The Tribunal accepts that Professor Mathews has attempted to bring some estimate of the Applicant's possible exposure dosage, but as the calculations appear to have started from an exaggerated base, consequently his conclusion and further estimates of Sr90 dosage on these figures are not reliable. The Tribunal notes that Dr Ilbery also had difficulty accepting Professor Mathews' figures. However, while they are of little help to the Tribunal in its deliberation the Tribunal accepts, nonetheless, that Sr90 probably was present in the Hiroshima soil at the time the Applicant visited. Also, because of the 28-year half-life of Sr90, the levels in the soil would be greater than 90% of the level at Time Zero (18 months earlier).
In his report (exhibit A) Professor Mathews discussed a possible flaw in the Hiroshima Study, which compared the leukaemia and cancer rates amongst those exposed to the acute radiation (in city) with those coming in later (not-in-city). The cumulative exposure in the latter group was estimated at no more than 20–30 mSv. Because of the possibility of the not-in-city group, which was the scientific control group, also being exposed to fallout radiation, undetected or randomly, one cannot be certain about exposure, nor can one be certain about the base-line rates of leukaemia/cancer in those who were truly "not exposed" (exhibit K, Ch.6). However the low estimated cumulative dose for the not-in-city group is a problem for the Applicant's hypothesis. The reported "not-in-city" group entered Hiroshima seven months earlier than the Applicant. Presumably they worked in the area and therefore were also covered in dust at various times. Therefore, they were exposed to an environment very similar to that on which the Applicant based his claim for Sr90 absorption. Putting aside the figures of only 20–30 mSv cumulative dosage for this group, the group also has not shown any incidence of solid tumours or blood dyscrasia. The study was reported by Kato H and entitled Cancer Mortality (In GANN Monograph on Cancer Research, 1986; 32:53). Dr Ilbery relied on that study (exhibit 1, p 10) and concluded that –
In view of the magnitude of the exposure dose and the fact that the irradiation of the early entrants was chronic and not acute as in exposure to A-bomb radiation, a remarkable increase in radiation induced cancer seems highly unlikely.

Dr Ilbery noted from personal correspondence with the Radiation Effects Research Foundation ("RERF") in Japan that leukaemia is not increased among those who entered the Hiroshima or Nagasaki area within one month after the bombing. The Tribunal assumes that those to whom reference is made by the RERF were, if anything, more exposed than was the Applicant.

It seems sensible to the Tribunal that without any firm quantitative evidence of the actual dose of long half-life nuclides in the soil or in the bodies of this not-in-city group, or the Applicant, that the epidemiological studies of the not-in-city group could supply some more objective evidence, rather than speculative theory. Firstly it would include the effects of all possible forms of radiation, that is, both internal and external. Secondly it would be a more generous comparable group because of its probable greater exposure to the same environment as would the Applicant. Thirdly, this group would also contain a spectrum of people with decreased inherited ability to repair any DNA damage possibly caused by beta radiation of their bone marrow. This last factor was a further non-assessable dimension postulated by Professor Mathews. Thus, on the evidence before it, the Tribunal considers that this comparable group, which has been the subject of epidemiological research by a reputable organisation, creates a significant medical fact that the probable dosage of internal radiation to which the Applicant was exposed from an epidemiological viewpoint does not produce an increased incidence of cancer.
Professor Mathews opined that if the Applicant had absorbed Sr90 it would still be detectable in his body, and that even taking into account the shortened half-life of 15 years of Sr90 in the body it could be measured by a total body scan. However, this test was not done, and so significant achievable evidence is not available to the Tribunal. It would seem prudent for the Respondent to investigate the feasibility and reliability of this test as an objective indicator of significant internal radiation for future claims of this nature.
consideration of other decisions of the tribunal related to myelodysplastic syndrome
Re Estate of Redenbach and Repatriation Commission (1990) 21 ALD 738, the veteran was based at Bofu, about 90 miles from Hiroshima and had documented evidence of one visit to the site of the Hiroshima bomb explosion. He had claimed he had made at least five such visits, ate local food and also fossicked among the bomb site ruins. The Tribunal accepted that he made more than one visit. His exposure was probably greater than that of Mr Davis but the difference is not of great significance. The Tribunal accepted that a reasonable hypothesis existed that internal radiation caused his myelodysplastic syndrome.
Re Repatriation Commission and Thorne (1989) 17 ALD 251, the veteran was stationed 7 to 8 miles from Hiroshima (within range of dust contamination) for nearly 3 years (1946 to 1949). He had cuts and scratches that were a source of entry of internal radiation. In that matter the Tribunal found that he could have absorbed a speck of Sr90 on a cordon and search operation and other activities. Whilst the veteran had a significantly greater exposure period than Mr Davis, the principle that a single speck of Sr90 could cause damage because of the dangerous properties of beta radiation was accepted as a reasonable hypothesis.
Re Hill and Repatriation Commission (AAT 7535, 11 October 1991), the Tribunal was required to determine whether there was a reasonable hypothesis connecting the veteran's non-Hodgkin's lymphoma with war service. The veteran had 15 months' service at Kure and he visited Hiroshima regularly. On many occasions he ate local food and drank local beer whilst in Hiroshima. The Tribunal considered submissions regarding the connection between internal and external radiation and decided that the material before it was sufficient to establish that the veteran could have been subjected to internal radiation consequent upon his exposure to the aftermath of the atomic bomb explosion over Hiroshima. That decision also excluded external radiation as a factor. Dr Ilbery also gave evidence in that matter. He conceded that the genetic differences between Japanese and Caucasians was a causative factor in the low incidence of non-Hodgkin's lymphoma in the Japanese people. He agreed, "grudgingly", that low dose radiation, combined with co-factors, such as genetic differences or viral factors, could be associated with the development of cancers. The Tribunal notes that the acceptance of a genetic difference between Japanese and Caucasians decreased the significance of the problem that the Tribunal had in accepting the hypothesis as reasonable.
has a reasonable hypothesis been raised in this case?
The High Court in Re Byrnes v Repatriation Commission (1993) 177 CLR 564 at 571 stated –
The hypothesis will not be reasonable if it is contrary to known scientific facts or is obviously fanciful or untenable. If the hypothesis is not reasonable the claim fails.

The Full Federal Court in East v Repatriation Commission (1987) 16 FCR 517, to which the High Court in Byrnes (supra) cited with approval, said –

A reasonable hypothesis requires more than a possibility, not fanciful or unreal, consistent with known facts. It is an hypothesis pointed to by the facts, even though not proved on the balance of probabilities.

The High Court in Byrnes said in respect of the Full Federal Court decision in East –

That understanding of the expression gives force to the word "reasonable", is strongly supported by the history of the relevant provisions, and accords with the intention appearing in the Minister's second reading speech and with authority.

Although the Applicant in East's case submitted that –

… provided that there is a real possibility of a causal connection between war service and incapacity or death and in the absence of proof beyond reasonable doubt of facts negativing that relationship, the claim must succeed

the Full Federal Court said in response (at 532) –

We do not accept this submission. It seems to us to pay insufficient regard both to the history of the legislation and to the meaning of the phrase 'reasonable hypothesis'.

The Court continued –

The addition of the word, 'reasonable' would however seem to imply that what is required is more than a mere possibility. … to be reasonable, a hypothesis must possess some degree of acceptability or credibility – it must not be obviously fanciful, impossible, incredible or not tenable or too remote or too tenuous. For a reasonable hypothesis to be raised by the material … it must find some support in that material – that is, the material must point to, and not merely leave open, a hypothesis as a reasonable hypothesis.

It was submitted for the Respondent that the Applicant's hypothesis relies on a series of assertions, which the Respondent questioned, as follows –

Can myelodysplastic syndrome be attributed to ionising radiation? Dr Wiseman noted that the cause of myelodysplasia is not known, although she suggested that its aetiology was the speciality of haematologists. She was not aware from studies in Hiroshima that there was any higher incidence of myelodysplasia in people subjected to that environment. Dr Ilbery (exhibit 1) noted that the aetiology of the condition was unclear, but some people develop the condition secondary to chemotherapy, with or without accompanying radiation therapy. He acknowledged one author who held that myelodysplastic syndrome induced by radiotherapy alone was an unusual but recognised event. He reported that in the high dose group of atom-bomb related cases, the frequency of myelodysplastic syndrome was high, and it has been recorded following massive doses of radiation received accidentally. Dr Ilbery noted that the concern in this case is with low dose and low dose rate. He said (exhibit 1, p7) –
At low doses and low dose rates the estimates of risk are tenuous since the excessive risk is small and the sample size needed to demonstrate an effect is prohibitively large. Further a radiation-induced cancer is clinically indistinguishable from cancers caused by other factors.
Thus the probability that cancer will result from a low dose can be estimated at the present only by extrapolation from the increased rates of cancer that have been observed after higher doses.
Unique chromosome configurations may predate malignant change as in the aberrations present in the preleukaemic phase of radiation induced leukaemia. Radiation brings about structural damage in macromolecules. The critical target for such injury in living cells is desoxyribosenucleic acid (DNA), the blueprint of inheritance. Hence delayed consequences of radiation exposure are genetic changes and cancer. In the intermediate dose range the relationship of dose to carcinogenicity is a linear to linear-quadratic model with a negative gradient becoming apparent in the high dose range where cell killing predominates over mutations while the shape of the gradient defies determination at low doses. There is an analogy in experiments scoring chromosome damage in cells such as lymphocytes following graded doses of radiation. The shape of the gradient as the dose falls below 100 mSv does not follow a linear response down to the level where chromosome damage due to natural background radiation might be expected to be seen at 1-2 mSv.
In regard to the uncertainty in its preferred models, the BEIR V Committee at page 181 gave this well under emphasised caveat: "Finally, it must be recognised that derivation of risk estimates for low doses and dose rates through the use of any type of model involves assumptions that remain to be validated. At low doses, a model dependent interpolation is involved between the spontaneous incidence and the incidence at the lowest dosage for which data are available. Since the committee's preferred risk models are a linear function of dose, little uncertainty should be introduced on this account, but departure from linearity cannot be excluded at low doses beyond the range of observation. Such departures could be in the direction of either an increased or decreased risk. Moreover, epidemiologic data cannot rigorously exclude the existence of a threshold in the millisievert range. Thus the possibility that there may be no risks from exposures comparable to external background radiation cannot be ruled out. At such low doses and dose rates, it must be acknowledged that the lower limit of the range of uncertainty in the risk extends to zero".
….
There is an important distinction between scientific estimation of risk at low doses of radiation, which could be very small indeed, and arriving at a prudent estimate. The latter prudent approach is justified for radiation protection purposes in the development of radiation standards to protect workers and the public. The former is a realistic best-estimate approach while the latter tends to overestimate or exaggerate the risk. ……
…the biological effectiveness of radiation at low doses and dose rates is not the same as at high doses and dose rates so that, while satisfactory for radiation protection purposes, such proportionality, frequently assumed, does not necessarily apply.

It was submitted for the Respondent that on the basis of Dr Ilbery's evidence that the hypothesis was tenuous, and on the basis of the case law on the subject, the Tribunal should not find that it is a reasonable hypothesis. However, when the Tribunal considers the abovementioned extract of Dr Ilbery's opinion taken holistically, and applies the test imposed by the Full Federal Court in East (supra), the Tribunal considers that the Respondent's approach to the consideration of whether an hypothesis is reasonable is too simplistic. In considering all the expert evidence, including that of Dr Ilbery, the Tribunal finds that the hypothesis possesses some degree of acceptability or credibility. It is not contrary to known scientific facts. It is not obviously fanciful, impossible, or incredible. While it is remote and tenuous on the evidence of Dr Ilbery, the Tribunal finds that it is not "too remote" or "too tenuous". The Tribunal considers that part of the hypothesis that suggests that myelodysplastic syndrome is attributed to ionising radiation, finds some support in the evidence provided by Professor Mathews and Dr Ilbery. The Tribunal finds that the evidence points to the hypothesis, and does not merely leave it open.

Was the Applicant exposed to ionising radiation? It was submitted for the Respondent that on the evidence of Dr Ilbery the dose from residual radiation when the Applicant visited the bomb site for a total of less than 16 hours would not have been more than 1 mSv. It was submitted that Professor Mathews was of the opinion that the only way that the Applicant could have been exposed to a very significant amount of radiation would be if he carried some of the radiation away with him. It was submitted for the Respondent that there are no facts which point to the hypothesis that Sr90 was in the soil, food or water at the time of the Applicant's visit to Hiroshima. The rainfall prior to his visit would have removed the short-term particles from the air and so they would not have been inhaled, and indeed because his visit was confined to around the hypocentre that was not an area of heavy fallout in any event.

The Tribunal finds that small amounts of Sr90, Cs137 and Cobalt60 and traces of Uranium remained in the soil when the Applicant was in Hiroshima. There remains no significant challenge to the hypothesis that the Applicant could have ingested a small speck of, say, Strontium and/or other nuclides, which could have deposited a long-duration, low dose of beta radiation close to his bone marrow.
The Tribunal notes the submission for the Respondent that, relying on the Federal Court decision in East (supra) the Tribunal should find that the terminology used by Professor Mathews such as "not inconceivable" and "a possibility" and "not entirely fanciful" was insufficient to raise a reasonable hypothesis. The Tribunal has considered this carefully in the context of the complex and detailed scientific evidence before it. The Tribunal's consideration of whether the hypothesis is reasonable goes beyond the language used by Professor Mathews to support the hypothesis, but to the scientific arguments themselves. Finally, the Tribunal notes the necessity to decide whether the hypothesis is reasonable, fanciful, too tenuous or impossible, taking into consideration all the expert evidence before it.
The Tribunal notes the submission for the Respondent that, notwithstanding that there is no Statement of Principles binding the Tribunal in this matter, the Tribunal should note that the Statement of Principles for both Acute Myeloid Leukaemia (Instrument No. 169 of 1996) and Chronic Myeloid Leukaemia (Instrument No. 7 of 1997) identify the following factor in order for a reasonable hypothesis to be raised –
Having been within four kilometres of the epicentre of the atomic bomb explosions on Hiroshima or Nagasaki within the seven days immediately following the explosion on those cities, before the clinical onset … (Respondent's emphasis)

It was submitted for the Respondent that the Applicant would not satisfy this factor, and that no other factor has been satisfied. It was also submitted that it would be illogical for the Tribunal to accept that the aetiological factors of leukaemia are relevant for the purposes of considering the aetiology of myelodysplastic syndrome without also considering the corresponding Statement of Principles.

The Tribunal has difficulty with this submission as a matter of principle. In effect, the Respondent's argument is that even though the condition before the Tribunal has no relevant Statement of Principles (and the Tribunal notes that the ICD codes relevant to the Statements of Principles in respect of Acute Myeloid Leukaemia and Chronic Myeloid Leukaemia do not incorporate the condition of myelodysplastic syndrome), nonetheless the Tribunal should select and apply a Statement of Principles relating to a condition which has some of the same features as the condition being considered by the Tribunal. Moreover, not only are the ICD codes different, but the ICD code for myelodysplastic syndrome comes under a different classification category from that which includes myeloid leukaemia. In any event, whatever the logic might or might not be, such an approach is contrary to s120A(4) of the Act and would lead to an error of law.
Having considered all the material before the Tribunal and the previous decisions of the Tribunal relevant to this hypothesis the Tribunal finds that pursuant to s 120(3) of the Act a reasonable hypothesis has been raised by the Applicant connecting his myelodysplastic syndrome with his war service.
has the hypothesis been disproved beyond reasonable doubt?
The Applicant agreed in cross-examination that he had worked for the Rockdale Council. In 1985 and again in 1991 he had been exposed to a toxic spill. The first was a black liquid. He recalled assisting the Fire Brigade to remove the spill. The second incident involved a spill from a semi-trailer of part of its load of pesticides onto the road. He denied any knowledge that either of these spills contained benzene, and he noted that the procedure for a benzene spill was not followed in either case. He did not know what chemicals were involved in either spill.
The Applicant's evidence was that he felt unwell for a week after the first spill. Subsequently he had a blood test, which led to the diagnosis of myelodysplastic syndrome. Later he commenced a civil claim for damages in respect of these incidents, but he did not proceed with the claim and no legal liability was found.
Dr Warwick Benson , physician, in his report dated 21 July 1988 (exhibit E) was unable to identify a link between the Applicant's condition and benzene exposure, and he noted that the only organic substance that has been clearly linked causally to the development of leukaemia or myelodysplasia was benzene. This view was shared by Dr Puflett, physician (exhibit F) who also cast doubt over the possible role of benzene in the causation of leukaemia. However, that view was not shared by Dr Joshua, haematologist (exhibit G).
The Tribunal is satisfied that there has been no exposure to benzene or other possible chemicals that may be implicated in the genesis of myelodysplastic syndrome. However, even if there had been chemical exposure, that of itself would not disprove the hypothesis raised beyond reasonable doubt. It would merely raise another hypothesis.
It was submitted for the Applicant that Dr Ilbery's evidence does not go to the ingested radionuclide hypothesis. His evidence about levels of residual radiation go only to external radiation. Therefore, even if that evidence was accepted in its entirety the ingested radionuclide hypothesis would remain. It was submitted that only if the Tribunal could be satisfied beyond reasonable doubt that no radionuclide remained in the vicinity of the hypocentre at the time of the Applicant's visit could the ingested radionuclide hypothesis be dismissed. It was submitted that the scientific evidence is to the contrary. It was also submitted that Dr Ilbery's evidence must be interpreted as conceding that in addition to background radiation there was a level, albeit low, of additional radiation. Hence, the induced radiation hypothesis was not disproved.
It was the Respondent's case that no reasonable hypothesis was raised. The Respondent made no submissions as to whether, if a reasonable hypothesis had been found to be raised, was disproved beyond reasonable doubt.
In considering all the evidence the Tribunal considers, pursuant to s120(3) of the Act, that the hypothesis raised on behalf of the Applicant has not been disproved beyond reasonable doubt.
Having come to this decision the Tribunal notes that the evidence leaves considerable doubt about the relationship between the Applicant's condition and his visit to Hiroshima some eight months after the atomic bomb blast. However on the evidence the Tribunal is unable to be satisfied beyond reasonable doubt that the hypothesis has been disproved.
The Tribunal therefore sets aside the decision under review and decides that the Applicant's condition of myelodysplastic syndrome is a war-caused condition and that the Commonwealth is liable in respect of that condition with effect on and from 9 November 1995. The matter is remitted to the Respondent to assess the rate of pension payable to the Applicant.

I certify that the 56 preceding paragraphs are a true copy of the reasons for the decision herein of Mrs M T Lewis, Senior Member, Dr M E C Thorpe, Member, and Dr P D Lynch, Member
Signed:         .....................................................................................
  Associate
Date/s of Hearing  15 December 1998, 23 March 1999
Date of Decision  10 May 2000
Counsel for the Applicant        Mr John Fitzgerald
Solicitor for the Applicant         Rockliffs Solicitors and Attorneys
Counsel for the Respondent    N/A

Solicitor for Respondent Ms Melinda Doggett, Dept. of Veterans' Affairs