HC Deb 25 July 1983 vol 46 cc956-67 4.31 am
Mr. David Alton (Liverpool, Mossley Hill)

Having listened to the Minister's concluding remarks in the last debate I was tempted to plunge into that minefield of credit tax, housing benefits, welfare, housing, pensions and the rest, but I should like to turn the attention of the House to another issue — the atomic explosions in the South Pacific in the 1950s and the effects that they had on service men and civilians who were in that region at the time.

I thank the Minister of State for coming here at 4.31 am to reply to the debate. I sympathise with him for having to be here at this time. He will accept that it is not the fault of right hon. and hon. Members who raise such important subjects that we organise ourselves in such a crazy way that debates have to take place at this time. I am sure that the Minister will put up with that and do his best to answer this important debate.

There has been growing, concern about the issue, in the last six months in particular. I shall draw attention to three main areas. First, I shall refer to the events which took place back in the 1950s in Maralinga and Christmas Island. Secondly, I shall talk about the survey which the Government said should be conducted. Thirdly, I shall talk about the compensation procedures which might be invoked if the survey concludes what many experts say that it might.

I became interested in the subject at the beginning of the year when The Sunday Times highlighted the case of a Royal Navy officer, Mr. Bill Grigsby. It recorded the claim by his widow, a Liverpool woman, that he had died in 1977 from the effects of an atom bomb test at Maralinga in South Australia.

One month before that, the BBC's Nationwide programme highlighted accounts of service men involved in the nine South Pacific tests between May 1957 and November 1958. The local base at that time was Christmas Island.

In answer to questions in the House the Prime Minister confirmed that Approximately 12,000 British service men and 1,500 British civilians participated in the test programmes together with about 1,500 Australians."—[Official Report, 8 February 1983; Vol. 36, c. 291.] Nationwide, in a devastating programme, pointed to evidence which suggested that many of those 15,000 men and women who were present at the 21 British atmospheric tests held between 3 October 1952 and 23 September 1958 were exposed to the effects of radiation.

It is to that most serious of allegations that I want to bring the attention of the House this morning. Following the publication of The Sunday Times article, I made contact with Bill Grigsby's widow, who still lives on Merseyside. She told me that her husband's job had been to clear the Maralinga area of its aboriginal inhabitants before tests were conducted, and then to collect radioactive particles and to measure fall-out. She said that her husband had told her that he was never issued with any protective clothing and that on one occasion he came across a group of aboriginals, squatting around a small fire, in an atom bomb crater. They were covered in sores. Mrs. Grigsby is convinced that when her husband died from cancer in 1977 it was directly attributable to the effects of radiation.

The Australian Nuclear Veterans Association has traced 600 of the Australian ex-service men involved at Maralinga. Its findings are quite chilling. Of the 600, 114 have died—and, like Bill Grigsby, 109 have died of cancer.

Despite many such examples, on 8 February the Prime Minister said in a written answer that: the records indicate that no one involved in the British nuclear tests in 1957 suffered exposure in excess of the internationally recognised limits at the time."—[Official Report, 8 February 1983; Vol. 36, c. 291–92.] That view is not shared by many service men and their relatives or by many eminent men and women. Writing in The Lancet on 9 April, three doctors at the Department of Social Medicine of the University of Birmingham said: The follow-up of the South Pacific population is far from complete but already there is evidence of an abnormally high incidence of leukaemia and other RES … neoplasms. In a supporting letter from another seven doctors which was also published in The Lancet, it is stated: There is a strong indication that some of those involved had received radiation greatly in excess of a safe dose. Bowing to the pressure from hon. Members on both sides of the House, the Secretary of State for Defence announced in January that public disquiet necessitated the need for a survey. On 18 January I asked the Prime Minister whether she thought a survey was adequate. I said: Does she not agree that simply making available service men's records is insufficient and that what is required is a public inquiry and an assurance that compensation will be given to the victims and their relatives?" — [Official Report, 18 January 1983; Vol. 35, c. 166.] In reply, the Prime Minister said that she believed that a survey of 15,000 personnel was the best way to go about the problem.

Since that reply it has become clearer how the survey is to be conducted, although many would still argue that its remit and its terms of reference are inappropriate. What has become less clear is the number of people who are to be surveyed and who is to be surveyed. In January, the Prime Minister said that it was to be 15,000 people, but in April, in the other place, Lord Glenarthur, in reply to Lord Jenkins of Putney, put the figure at 13,500. He said that this would be To avoid statistical bias …"—[Official Report, House of Lords; 11 April 1983, Vol. 441, c. 92.] Then on 14 July in answer to a written question from me, the Prime Minister said that the survey will be higher than previously estimated, and could be around 20,000. These will include support personnel who worked in areas away from the test areas and others who were, at the time, not considered to be at any risk from radiation exposure."—[Official Report, 14 July 1983; Vol. 45, c. 394.] Surely that does exactly what Lord Glenarthur was at pains to prevent. It increases the figures to lessen the impact of any illness statistics. It builds in a statistical bias. The Minister should tell the House who are these additional 5,000 people. Have they been included so that the percentage of people appearing to have contracted cancer will be reduced? If not, why are these people now considered to have been at risk from radiation exposure when in January they were not considered to have been at risk? Otherwise, he will run the risk of being accused of cooking the books when the survey is published.

I hope that the Minister will tell us whether the report in The Observer last Sunday was correct. It stated that the National Radiological Protection Board is to conduct the survey. If that is correct, perhaps the Minister will explain why the Prime Minister omitted that information in her reply on 14 July. She said: A contract, to be funded by the Ministry of Defence, will be placed shortly for the detailed conduct of the survey by an independent organisation." — [Official Report, 14 July 1983; Vol. 45, c. 394.] Why was the name of the organisation withheld from the House just 11 days ago? Surely the truth is that there will be little confidence in the NRPB, because it is not wholly independent. The Ministry of Defence, in whose interests it is to disprove the findings of the university of Birmingham, is to be the paymaster for the survey. The Ministry already uses the services of the board, which will be open to the charge of being in the Ministry's pocket.

The Minister should tell the House how many cases involving suspected radiation effects on service men have been referred to the board for investigation in the past and how close existing links are between the NRPB and his Ministry. He should also say what other organisations were considered for the work and whether any thought was given to the independent financing of an academic body, say through the Medical Research Council.

In that way, the sceptics among us would have felt far more confident about the outcome of the survey. We would have trusted more in the impartiality of the survey and would have no cause for feeling, as many of us do, that the watchdog is being far too closely identified with the burglar.

The survey is to take an agonisingly long time. Perhaps the Minister will confirm or deny that it could take up to three years for the survey to be completed. Does he know the view of Mr. Ken McGinley, the chairman of the British Nuclear Test Veterans Association, who said at the weekend that the Ministry is using the survey as a delaying tactic to stop service men obtaining compensation? Mr. Tom Armstrong of the same organisation told me yesterday morning that he failed to see how it could take three years to establish whether there is a significantly higher level of cancer, leukemia and cataracts in test veterans than in the outside population.

What of the terms of reference of the survey? It will be simply a soul-cleansing charade unless full access to the medical histories of all those involved in the test is permitted, and all the findings should surely be made public. If the Ministry is prepared, as it says, to release service medical records to the doctor of any ex-service man who asks for them, why cannot information be extrapolated for the purpose of the survey as well?

Similarly, if the survey is to take no account of genetic effects, which is what we are told, how will we extend our sketchy knowledge of radiation damage? Most of what we know is based on the inadequate evidence gleaned after Hiroshima and Nagasaki and some leading scientists, including Dr. Joseph Rotblatt, one of the world's leading radiation experts, believe that much of the evidence gleaned earlier is out of date. He says that there is no such thing as a safe threshold for radiation doses. What is required is a thorough and exhaustive investigation which takes new ideas into account.

Perhaps the Minister will tell the House what he hopes to learn from the survey and say how the findings will be presented. For example, will they be broken down into categories and age delineation? Will the instances of cancer be broken down into those that are common to the whole population and those that are specifically radiation related?

If all that is not done, the Government's sincerity and motives will undoubtedly be questioned and the whole exercise will be rendered useless. As the joint committee on the medical effects of nuclear war said to me in a letter signed by Dr. Stewart Britten, that I received yesterday morning: If the Government continues in its failure to disclose all the information available to it—or if it entrusts an investigation to a body which is not fully independent— it will only serve to bring discredit upon itself. Regarding the conditions which applied at Christmas Island and Maralinga, does the Minister of State stand by the letter which he sent to his hon. Friend the Member for Esher (Mr. Mather) on 29 March of this year in which he said: The Ministry of Defence believes that none of those present suffered any measurable effects to their health as the result of exposure to radiation at the tests. He went on to say that the safety standards in force in the 1950s were not markedly different from those used for radiological protection today. Also, the most stringent precautions were taken to ensure that the safety standards were observed. If that was so, how does the Minister react to the accounts of servicemen who recall being blown 20 feet by the blast and who, having covered their eyes as instructed, could see the flash and the outline of the bones in their hands? Not only were the controls primitive, but in the case of tests at Christmas Island, where weapons were exploded over the water, the surface waters over a wide area must have become highly contaminated. The Ministry say that the nearest service men were 15 miles away, but that is hardly a great distance in terms of wind and water movement and fallout. That was not stringent control.

Similarly in the case of Warrant Officer William Jones, recorded in an Australian compensation claim; this is not just anecdote. It indicates an extraordinary absence of radiological control. Warrant Officer Jones died of cancer aged 39, 13 years after his involvement in the tests. He and his crew were in charge of a Centurion tank placed adjacent to ground zero. The intention was to see how well it survived in test blast heat and whether it could be started and driven off after exposure.

Following the explosion, the tank would not start, and while his crew went off to obtain parts, Warrant Officer Jones stayed with the tank for the next 48 hours. The cobalt in the tank's steel under nuclear bombardment became radioactive and Warrant Officer William Jones subsequently died of blood cancer. Was that stringent control? Is the Minister really saying that the safety conditions of 30 years ago should suffice today?

When the Minister replies, he will no doubt cite the New Zealand report on levels of radiation on Christmas Island. It would be useful if, at the same time, he would say why the British report, which was conducted into sites on the island in 1964 and which detailed the sites contaminated, has never been published. Surely it should now be made available in the House of Commons Library, if the Government have nothing to conceal.

The Minister might also like to make available to hon. Members the proceedings of the Congressional hearings now examining the claims of the American Atomic Veterans Association; the reports of Australian compensation cases; and the findings of the American inquiry in 1957 after the explosion known as "Smoky". None of those would give hon. Members cause to believe that safety regulations were either stringent or satisfactory.

I come to another highly unsatisfactory situation. There has been no denial by the Government of a damning indictment by the Australian Ionising Radiation Advisory Council. The report was issued in June and said that the British authorities decided that 200 British and 62 Australian servicemen should experience the effects of an atomic blast at a closer range than normally allowed. The men were situated just five miles from the 20 kiloton bomb, which was about the same size as the bombs dropped on Hiroshima and Nagasaki.

Three days after the explosion, 100 of those participants were taken into the contaminated area and then, after tests, were decontaminated. The suggestion in the Australian report is that British service men were used as atom bomb guinea pigs, and that is profoundly disturbing. If true, the Government have a duty to make known the names of the military personnel who issued such inhumane and immoral orders. They will be failing in their duty to our service men if they do not.

Despite the Government's claim that there is no evidence that anyone has suffered ill-effects, a war service pension was awarded last year to a widow, Mrs. Marjorie Stephens, whose husband died of leukaemia 20 years after serving on Christmas Island. Yet Mrs. Grigsby of Liverpool, whose case I mentioned at the outset, has not succeeded in getting a war widow's pension. Her claim, along with others, was turned down by the Department of Health and Social Security. Perhaps the Minister will explain the different criteria that apply in the different cases. I hope that he will confirm that even if disease or death can be proved to have resulted from atomic test participation, there is still no guarantee of compensation under British law for service men or their relatives. Section 10 of the Crown Proceedings Act 1947 bars common law claims against the Crown by service men who sustain injury or disease that is attributable to their service. In the United States, about 1,200 civilians are claiming compensation following the Nevada case. The service men there, as in Britain, cannot sue. That is a matter that is currently before Congress. In Australia, however, service men are allowed to sue, and some have already done so successfully. Surely we should be amending our laws to enable our service men to take similar legal action. What point will the survey ultimately serve if redress is denied?

It may be suggested that the number of deaths caused by cancer in the population generally is no different from those among service men who are involved in the tests to which I have referred. For some time that was the misleading and complacent response of the Ministry of Defence. The Ministry is well aware that objective research has shown that the incidence of blood cancers specifically related to radiation has proved to be much higher among service men than is normal. The Birmingham university report calculated the number of blood cancers among identified service men to be two and a half times the normal incidence rate.

It would be obscene to be complacent. The experience in the South Pacific 30 years ago may be crucial to human safety in future. That is why it is so important that the Government show a sense of urgency in conducting a survey, why it is important that the survey is conducted by a truly independent and non-governmental body, why all information that is gathered is made publicly available, why allegations that our service men were used for laboratory testing are answered, why safety measures are urgently reviewed and why suitable remedies through the courts are provided for families who have lost loved ones, or those who are still suffering the effects of leukaemia, early cataracts and skin eruptions caused by exposure to radiation or exposition to contamination from fall-out.

I hope that the Minister will be able to deal with all these important matters when he replies.

4.53 am
Dr. Oonagh McDonald (Thurrock)

A number of questions must be put to the Government. The first concerns safety measures, to which the hon. Member for Liverpool, Mossley Hill (Mr. Alton) has referred. In a report in The Observer on 9 January, certain claims were made about what one can only describe as suppression of information about safety measures. The report claims that none of the key files about blast and radiation precautions have been released nor have Cabinet minutes about reports on the test programme. One of the questions that we must ask the Minister is whether that statement is true. If the key files have not been released, why has that not happened, bearing in mind that the Ministry of Defence has recently said that there is no change in its total satisfaction with the safety measures at the time?

Because of the anxiety that is now being expressed, it would be better if all the information about the safety measures at the time were made fully available so that the House can judge whether the Ministry of Defence is right to be totally satisfied with them. The reason for that has emerged even more strongly as a result of the Congressional hearings in May relating to the papers of the late Colonel Stafford Warren which were released as evidence and about which questions were asked.

Having reviewed that evidence, Dr. Alice Stewart of Birmingham university, whose research has promoted interest in the issue, claimed that the new American evidence accorded more with the veterans' account of safety arrangements than with the official versions. If there is a possibility, as many veterans suggested, that the safety measures were not adequate and not properly enforced and that nuclear waste disposal was treated casually, we need to know and to ensure that safety measures are improved.

What changes have been made to the safety measures in handling radioactive materials? Has change been necessary? Is there room for improvement, or is the Ministry of Defence entirely satisfied with measures that were thought suitable on what seems to have been inadequate information 30 years ago?

It would be interesting to hear the Minister's comments on the claim in The Observer article, to which I referred, that the American Government were secretive about all aspects of the atomic bomb programme and refused to share information about blast and radiation effects. If that is so, it is possible that our safety measures were inadequate, because British researchers did not have adequate information. Is that so? If it is, what improvements have been made in the light of knowledge that must have been gained in the past 30 years?

Will the survey last two or three years, and how is it to be conducted? In a letter to The Lancet on 9 April 1983, a group of doctors from several hospitals, including St. Mary's and the Welsh national school of medicine, outlined the form that the survey should take. They wrote: The servicemen present at the nuclear test explosions constitute a uniquely large sample of healthy young men who were at risk of exposure to ionising radiation and among whom there now appears to be evidence of radiation related effects. To examine as fully as possible their subsequent medical histories, access to a complete nominal roll of the total group of exposed persons is required, together with full disclosure of what is known about radiation exposure of the men on duty during these tests. We urge that an independent academic body be asked to conduct a full investigation into the morbidity, mortality, and perhaps genetic effects in these men, and given the means to do so. Why is the Minister not suggesting that the personal medical records of those service men be made available, with their permission?

In a written answer on 10 March 1983, the Minister said that the central records accessible to the Office of Population Censuses and Surveys would give sufficient information, and that examination of the individual medical case histories would be of little or no assistance in achieving that aim and would add considerably to the length of time that the survey would take. I do not think that that is true, provided that sufficiently knowledgeable and experienced people look through the medical records.

Why does the Minister want to exclude those case histories? Surely one needs as full knowledge as possible of the medical history of the service men involved to judge whether any subsequent cancer has been caused by the effects of radiation. After all, it would appear that the two rather special types of cancer—leukaemia and cataracts —are more common among the service men involved in the tests in the 1950s than among the population as a whole. To get to the truth of the matter, one would surely need to know a great deal about their medical history. I do not think that a statistical survey would be sufficient. One would need to see whether there was any other reason for suffering from those forms of cancer, apart from the effects of radiation. There might possibly be other reasons for it, but it would be as well to know the truth one way or another.

It can only be to the Government's advantage to carry out a complete survey of what occurred then, partly to clear up any suspicions and partly to extend our knowledge of the effects of atomic warfare. The Minister will know full well that claims and counterclaims are made about the medical effects of nuclear warfare. Why not use this opportunity to make public as much hard information as possible? Surely the truth is the Government's best weapon. Every effort should be made to discover it.

I support the points made by the hon. Member for Mossley Hill about the need for compensation. If we find that people have been protected inadequately from the effects of radiation during their service to this country and have suffered not only illness and early death but painful and unnecessary illness, surely either they or their families should be compensated. That is a matter of justice and fairness. I urge that point on the Minister and hope that he will tell us what arrangements he will make for compensation if we find that service men have suffered unnecessarily from the conduct of those tests.

5.2 am

The Minister of State for Defence Procurement (Mr. Geoffrey Pattie)

I thank the hon. Member for Liverpool, Mossley Hill (Mr. Alton) for raising this important matter. I fully accept that it is hardly his fault that the debate has come on at this rather unusual hour. I assure him, the hon. Member for Thurrock (Dr. McDonald) and anyone reading the report of the debate that the Government take this issue extremely seriously and are determined to press on with the survey as a matter of urgency.

I remind the House that it is very important not to jump to the conclusions to which individuals who claim to have been affected would wish one to jump. We have considerable sympathy for them, but we must start from the incontrovertible observation that cancer is a major cause of death for a particular age group of the British population. Those who were involved in the tests that we are discussing tonight are now in that age group, and it does not necessarily follow that any deaths that may ensue now are directly related to the tests 25 years ago.

This debate reflects understandable concerns expressed previously in the House and in the media that the atomic test programme conducted in the South Pacific in 1957 and 1958 has bequeathed a legacy of illness to those who participated. The concerns are understandable because widespread publicity has been given to the carcogenic effects of radiation and because cancer is a common cause of death. However, in the special circumstances, there is as yet no evidence to justify the linking of those two facts. It is 25 years since we carried out atmospheric nuclear tests in the South Pacific, and the men who took part are now reaching ages where an increase in the incidence of cancers through natural causes must be expected. It is entirely natural for those men who contract cancer to question whether there could be a causal relationship with their earlier work in connection with atom tests. This possibility has been debated in the media on the basis of information collected from a relatively few, mostly non-typical, cases and, on the basis of those extremely limited data, attempts have been made to show that a causal link exists. I have examined all the claims that have been made so far and none has stood up to critical review.

When I first started to examine the questions about the possible health risks from our nuclear test programme, I was pleased to find how much attention had been given at the time to the details of nuclear safety. In the climate of the 1950s, when nuclear safety was not the issue that it is today, I might have expected safety standards to be somewhat relaxed. The evidence is quite the reverse, which may be at least partially due to the fact that many of those responsible for the nuclear safety of our tests had been brought up in the safety schools for conventional high explosives. The bases for high explosives safety had been skilfully adapted to the new situation and had been applied with the same thoroughness. The nuclear safety standards and procedures were drawn up and implemented with commendable thoroughness and bear favourable comparison with those in force today. The importance that was attached to nuclear safety is reflected in the recorded details of the events at that time.

I made it clear previously to the House that the safety arrangements for the tests required that an individual who might be exposed to radiation was issued with a dosimeter to record the actual exposure experienced. Those dosimeters, which were normally of the film-badge type, were read after each possible radiation exposure and the results recorded. The records have been retained in our archives, and they provide objective evidence that the exposure limits set before the tests were in practice respected. There were three such exposure limits. The lowest, which applied to an overwhelming proportion of those who were at any potential risk of a radiation exposure, was set at 3rem; the middle level for a small group undertaking special tasks essential to the success of the operations was set at 10rem; and for a very small group, primarily those aircrew personnel required to collect debris from the mushroom cloud, a level was set at 25rem. As my right hon. Friend the Prime Minister said in answer to a parliamentary question on 8 February 1983, at c. 292 of Hansard, the upper level was exceeded only twice when two service men were exposed to 30 rem. Applying today's radiological protection standards to events which occurred 25 years ago, the considered scientific judgment is that the radiation exposures measured during the south Pacific tests should not result in significant adverse health effects for the men who took part.

Questions have been raised, frequently on the basis of hearsay evidence, about men who were not monitored for radiation exposure because, as I explained, they were assessed at the time to be at no risk of such exposure. The cases that I have examined do not substantiate the claim that the assessments made at the time of the tests were in error. All the Pacific tests were carried out in accordance with programme plans, no tests gave a significantly enhanced nuclear yield, and no test was carried out at a place or time significantly different from expectation. In short, the test programme was carried out as planned, hence the radiation exposure assessments were not invalidated by any deviations in the test conditions.

In all, there were nine tests in the South Pacific—four in 1957 and five in 1958. There was seven air drops of devices with yields in the megaton range, and two tower shots in the kiloton range. No shot generated significant local fall-out. The Pacific tests were conducted in accordance with "Radiological Safety Regulations Christmas Islands" a publication issued by the director of the Atomic Weapons Research Establishment and enforced by the commander of the task force. The safety regulations were consistent with the recommendations of the International Commission on Radiological Protection and the advice of the Medical Research Council.

At shot time, all personnel were withdrawn from the area surrounding ground zero to a distance which ensured that they were not exposed to a significant level of prompt radiation from the explosion. Men were mustered out of the area. The test did not take place until it was positively established that the area had been completely evacuated. Prompt radiation consists of neutron and gamma rays. The attenuation of these rays by the atmosphere is well-established and, beyond a certain distance, the attenuation is heavy. Consequently, the definition of safe areas is highly reliable.

There was no significant local fall-out, so that the only other possible sources of radiation risk were the device itself while it was being prepared, materials of the environment which were activated by the prompt radiation and equipment which was contaminated by activation or debris.

Environmental activation for the South Pacific tests was minimal, even for the balloon shots, but post-shot entry into the area surrounding ground zero for the balloon events was strictly controlled by the health phycisists. All persons authorised to enter the area were monitored for radiation exposure, as were all those working on the assembly of the device and on decontaminating equipment. A special group consisted of aircrew who were required to fly into the debris cloud to collect samples for analysis. The sampling aircraft were specially modified for this function, the aircrew were supplied with the best possible protective equipment and, of course, they were radiation monitored. On return from a sampling mission the aircraft was decontaminated in an area set aside for this purpose.

The general limit on radiation exposure was set at 3rem, but for special activities essential to the success of the tests, higher limits were set at 10 and 25rem. Of all the men monitored, the radiation exposure of the vast majority was well below 3rem, most often not measurable above background. About 50 exposures were experienced in the range 3 to 10rem and less than 20 in the range of 10 to 25rem. Two aircrew were exposed to 30rem. Strictly speaking, radiation exposures should be expressed in Rontgen, but it is common practice to refer to rems. A rem is a measure of radiation dose and is now an obsolescent unit being replaced by the sievert. There are 100rem in 1 sievert.

The current recommendation for the maximum annual radiation dose for a worker certified to work with radiation—a classified radiation worker—is 5 rem or 50 millisievert, so that over a 40-year lifetime a classified radiation worker could accumulate a total dose of 200 rem. It is normal to make the conservative assumption that the health risk and the total exposure are linearly related, and that the risk of death each year for a radiation worker receiving annually the maximum radiation dose due to his occupation is about 1 in 1,000.

The average annual dose for a radiation worker is about one tenth of the recommended limit. On that basis, the death risk per year for the most exposed test personnel—30 rem or 0.3 sievert equivalent to about 8 millisievert per year for 40 years—is about one in 10,000. For those test personnel for whom the lowest radiation level applied —3 rem—the risk would be less by a factor of 10—one in 100,000. Those figures suggest that there is little likelihood of finding an enhanced death rate among the test personnel, but we will press on to see whether that is the case.

There have been allegations that some men failed to observe the safety regulations and hence were exposed to radiation hazards. While it is impossible to guarantee that there were no such occurrences, the records of the activities in the test area do not support those allegations. I am assured that a positive effort was made to monitor the observance of the safety procedures and that had there been any significant non-compliance with them, that fact would have been observed by those responsible for implementing the safety regulations.

While I am confident that the safeguards taken at the time were completely adequate, and hence that the test personnel were not subjected to any significant health hazard, I can only prove this to be the case on the basis of what has actually happened to the men in the 25 years since our atmospheric nuclear test programme ended. In view of the anxiety being expressed, I therefore announced in January this year that we needed up-to-date reliable information which would show one way or the other whether there was a problem. On 12 January 1983 the Ministry of Defence announced the intention to conduct a survey of the medical histories of both British service personnel and civilians who had taken part in the 1950s nuclear test programmes. This survey will be conducted on the basis of records already available to the Government and the prime objective will be to compare the experiences of test personnel with those of a similar group of service men and civilians who did not participate in the test programmes. The survey will, as already stated, be undertaken by an independent agency and it is intended to publish the results.

Before the Ministry of Defence can make arrangements for an independent agency to start work, it is necessary to define the populations which need to be considered in the survey and to identify the individuals within those populations in sufficient detail for their records to be traced. That is proving to be a major task. The investigations to date show that there are about 20,000 test personnel to be considered for the tests and other nuclear programmes carried out in Australia and the South Pacific. We have to ensure that we take account of everyone who might possibly have been at some risk, but avoid including those who were clearly at no risk; otherwise, the true test population would be diluted, as the hon. Member for Mossley Hill said, and the statistical comparisons with the non-test population would be biased. In addition to defining and identifying the test populations, we also have to construct statistically valid control populations so that effective comparisons can be made.

As I think the hon. Member for Mossley Hill is aware, the latest estimate of the number of personnel to be considered in the survey is about 20,000. That is an increase on the number given by the Prime Minister in February this year, when she referred to about 12,000 service men and 1,500 civilians.

There is plainly no change in the number of 4,000 men who were radiation monitored. They are well recorded. The uncertainty lies with those who were assessed at the time not to be at any radiation risk and therefore did not figure in the lists maintained by the radiological protection authorities. For the Pacific tests our best estimate of the number to be considered is about 12,000. The remaining 8,000 are associated with the Australian tests and other operations like the Maralinga experimental programme and the clean-up operations at Maralinga and Christmas Island.

I am sure that the hon. Gentleman would want, as I do, to ensure that the statistical base is correct. However, we face a dilemma. We do not want to exclude anyone, but if we trawl too deeply we will, as I said earlier, dilute the sample and therefore put the results at risk.

I assure the House that the survey will be carried out entirely without bias. Its purpose is to confirm or deny the validity of the assessment that we now make, on the basis of our knowledge of the safety precautions and of the radiation monitoring records, that the test personnel were not exposed to any significant health hazard. However, I must make it plain that the survey will not—and indeed cannot—provide direct evidence about individual cases. There is no way of determining whether a cancer contracted by an individual has been introduced by so-called natural causes or by an occupational exposure to radiation. At best it is possible only to allocate relative probabilities to the two possibilities. The survey will assist in calculating these probabilities.

A survey on the scale needed to produce valid results is, as I know the hon. Gentleman accepts, a major undertaking and it will inevitably take time to complete. Our present estimate is that results are unlikely to become available in less than about two years, but we are proceeding with urgency.

Mr. Alton

Will the hon. Gentleman answer two of the questions that I put to him earlier? First, will the independent body to be responsible for the survey be the National Radiological Protection Board? Secondly, as suggested in The Observer on Sunday, what about the allegation made in Australia in a report published by the Australian Government that British service men were deliberately exposed, almost as human guinea pigs, to higher levels of radiation than had originally been determined?

Mr. Pattie

I am not yet in a position to announce the identity of the body that will carry out the survey, but we shall want to do that fairly quickly. I am not aware of the report to which the hon. Gentleman refers, but the debate has been helpful in focusing the attention not only of myself but of my Department on what he has said. I shall examine the matter and, if I may, write to him, which is probably the best way to proceed.

The Government will continue to deal with claims that are made about possible adverse health consequences from participation in the nuclear test programmes, in accordance with the procedures that have already been described to the House.