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British Nuclear Test Veterans Association/ Green Audit Child Health Study 2007 Preliminary Analysis
Chris Busby Mireille de Messieres
Report 2007/5 GREEN AUDIT ABERYSTWYTH SEPTEMBER 2007
Abstract We designed and analysed a postal case-control questionnaire study of members of the British Nuclear Test Veterans Association to examine health in the children of the veterans. Controls were obtained by the veterans from friends and relations of approximately the same age, the method we recently employed in examining health for the Porton Down Veteran’s Support Group members. We were able to examine miscarriages, stillbirth, infant mortality, congenital illnesses and cancer for 605 children of veterans and 311 children of controls, a total of 916 children. We also obtained basic data on 1157 grandchildren made up of 749 veteran and 408 control grandchildren. Comparisons were made between cases and control groups but also analysed where possible against national rates for cancer and congenital anomalies on the basis of data from national cancer registries and five UK contributors to the EUROCAT registry on genetic anomalies (North Thames, Northern, Oxford, Trent and Wessex Regions). We obtained data on father’s exposure history and also data on mother’s smoking. Results showed high levels of miscarriages, stillbirths, infant mortality and congenital illnesses in the veterans’ children relative both to control children and expected numbers. There were 105 miscarriages reported in the veteran mothers compared with 18 in controls OR = 2.75 (1.56, 4.91; p = .00016). There were 16 stillbirths compared with 3 in the controls (OR= 2.70 (0.73, 11.72; p = 0.13). There were 57 veteran children with congenital conditions compared with 3 controls (OR = 9.77 (2.92, 39.3); p = 0.000003) these rates being also about 8 times those expected on the basis of UK EUROCAT data for 1980-2000 suggesting that the control children had not been selected for healthiness. In the grandchildren, these high levels of congenital illness also occurred with 46 veteran grandchildren recorded with congenital conditions compared with 3 controls OR = 8.35 (2.48, 33.8) p = 0.000025. There was higher infant and perinatal mortality in the veteran children than control children. There was a slightly higher cancer rate with 16 cancers reported in the veteran children and 5 in the control children. However we calculated the expected numbers using national rates and summing the 5-year expected numbers to show that the cancer levels in the veteran children were only 25% more than expected. The birth years of the children with congenital conditions was not clustered near the period of the test suggesting that the effects were unlikely to be associated with the acute external exposures. Indeed, most of the fathers had not been issued with film badges and many had only been at the sites between tests. We suggest that these results support our suggestion that the effects are caused by contamination of the veteran’s bodies by radioactive fallout and uranium. Many veterans reported suffering flu like illnesses, diarrhoea, skin burns and rashes which would support the idea of such contamination. We discuss the findings of this study in relation to earlier ones. We discuss the problems associated with self selection bias but argue that the astonishingly high levels of congenital ill health in the children and also grandchildren make it extremely unlikely that the results we see are more than partly associated with such an effect. The unusually relatively high levels of congenital anomaly in the grandchildren we suggest are due to genomic instability effects like those being found in the Chernobyl affected territories. It is clear that the veterans received significant genetic damage as a result of their period near the test sites. We recommend a re-analysis of the 1999 BNTVA data at Dundee University which we discuss.
1. Background The United Kingdom conducted a series of Atomic and Hydrogen bomb tests in the atmosphere in the period 1952-1963. These were conducted in South and West Australia and at Christmas Island and Malden Island in the Pacific. Moreover there were clean up operations until 1967. The question of whether the exposures of servicemen and others involved in the tests resulted in cancer has been examined in two studies of participants carried out in 1988 and 1993 (Darby et al 1988, Darby et al, 1993, Muirhead et al 2003). These studies suffered from serious problems which were discussed in the Committee Examining Radiation Risks from Internal Emitters (CERRIE 2004a, CERRIE 2004b) and at some length in Busby 2006. The principal error in the study protocols was that the classification of cases in the case control study was based on external exposure to gamma rays from a detonation and took no account of internal exposure to fallout. Thus film badge measured doses were used as a measure of the exposure. This is the same mistake which is at the base of the Japanese A-Bomb studies and underpins increasing criticisms of current radiation epidemiology (Busby 1995, Busby 2002, ECRR2003, CERRIE 2004a, 2004b, Busby 2006). However, since ionising radiation is a known mutagen, it was of interest to examine the health of the children of the UK A-Bomb veterans. Now that the children are as old as age 40 or more, if there were a transgenerational effect they might, besides the possible enhanced risk of genetic defect found in two earlier questionnaire studies (Rabbitt Roff, 1999, Urquhart, 1992), show increased rates of cancer relative to national populations or controls. In addition, we were also able to look briefly at the health of the grandchildren. The present study examines health conditions in the children and grandchildren of members of the British Nuclear Test Veteran’s Association and employs the questionnaire case control method which we recently applied to the Porton Down Veterans Support Group members (Busby et al 2006).
2. Methodology 1000 BNTVA members were sent questionnaires asking details of their participation in the A-Bomb Tests. They were then asked to give details of any miscarriages and birth outcomes, their children, the childrens’ early health and later health and also brief details of the grandchildren. Each veteran was asked to find a control of approximately the same age to fill out a questionnaire which gave the same details of the controls’ children and grandchildren. We permitted questionnaires to be filled in by spouses or children of veterans who had died. Table 1 gives the numbers of adults and children obtained through the questionnaires. Table 1 Number of veterans and controls and their children and grandchildren in the study group defined by the questionnaires
The health and various reported conditions of the three generations was then compared between cases and controls and also with appropriate national average rates for the diseases and conditions being considered. The information obtained is listed in Table 2. We made two approaches to analysing these data. The first was to treat the exercise as a case control study and compare conditions in the cases and the controls using conventional statistical methods to see if there were any statistically significant differences between the two groups. The second looked at expected values. In the case of cancer data this meant carrying out calculations to allow for the slightly different ages of the cases and the controls to obtain a meaningful result. Crude cancer rates are sharply affected by age and so a direct comparison between the cancer incidence in the cases and control children would be misleading. We calculated the expected number of cases of “all malignancy (excluding non melanoma skin cancer)” by applying the 1997 national incidence rates to each 5-year sex and age group of children and followed each 5-year cohort back in time to their birth, summing the total expected cancer numbers over their lifetime to year 2007. For example, for 34 males aged 40-44 in 2007 we apply the age 40-44 national annual rate to obtain their expected number of cancers in one year then multiply that by 5 to obtain all the expected cancer in 2002-2007. We then make this group 5 years younger and obtain the expected number of cases for 1997-2001, then repeat that process for 1992-1996 going back to their year of birth. All these expected numbers are added together to give the total lifetime expected number of cancers, which is finally compared with the number reported. We used the 1997 rates because the results are dominated by the older children and this year lies in approximately the middle of the lifespan of the children weighted for cancer incidence rate effects. Table 2 Information given by the cases and (where appropriate) controls
Test sites and operations were coded 3. Results Table 3 give results for miscarriages, stillbirths and congenital diseases or other congenital conditions in the children and grandchildren of veterans and controls. Table 4 gives similar data for the grandchildren of veterans and controls. Table 5 gives a list of all the conditions reported in the children which were included as likely to be congenital. Some of these (e.g. spina bifida) are clearly major accepted congenital anomalies (see Eurocat databases). Others are less serious or more uncertain about the genetic origin. Conditions that could be caused by difficult births e.g. cerebral palsy were not included. Table 5b records whether the mother smoked before the child was born, whether the father was issued with a badge, symptoms noticed by the father at the test site, when the child was born and which test area the father was stationed at. Table 6 lists the individual cancers reported in the children of the veterans and controls.
Table 3. Comparison of the children of veterans and controls with rates per 1000 live births where this can be calculated.
*see Table 5 for list of conditions included here; a rate per 1000;
Table 4 Comparison of the grandchildren of veterans and controls with rates per 1000 live births where this can be calculated
Table 5a. Conditions noticed in first few years “as reported” which are included for the purposes of this study as likely to be congenital and counted in Table 3 for both veterans and controls. Many reported possible congenital conditions were not included.
Table 5b Further details of the children tabulated in 5a above. Next to the child (Anom) is whether the mother smoked before birth, whether the father was issued with a radiation badge, any symptoms father noticed after the tests or whilst at the site, when the child was born and which test series code. Code 5 is Christmas Island, others are Australia.
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