Volume 6: Human Health, 1989-96
3. Introduction of the ban on Specified Bovine Offal
Discussion on the preparation of the Regulations
The nature of the exercise
Identification of the high-risk tissues
The approach of those involved
The choice of legislation
Delay
Tripe and rennet
Mesenteric fat
Casings
The exception for calves under 6 months
Mechanically recovered meat (MRM)

The nature of the exercise

3.632 The decision to introduce an SBO ban and the determination of the tissues that should be covered by the ban called for the application of principles of risk evaluation and management that are described in vol. 15: Government and Public Administration, ch. 5. As explained in that chapter, these principles were not at that time generally recognised in Government as tools to be consciously applied to policy-making. Certainly they were not in MAFF. The principles represent, however, the formulation of a logical approach to the handling of risk and we would expect the decisions made to reflect such an approach, whether or not the principles were expressly recognised and applied.

3.633 We have considered in the previous sections of this chapter the events leading up to the decision to introduce an SBO ban. That decision was not the product of a formal, or even informal, process of risk evaluation. It was largely a reaction to public pressure in circumstances where such scientific knowledge as existed gave no reassurance that the pressure was groundless but provided an underpinning for measures that would reduce the perceived hazard that was causing public concern.

3.634 The decision to introduce an SBO ban, nonetheless, was consistent with the ALARP principle. The ban was introduced as a precaution against what was considered to be a remote possibility that a risk existed. The removal from the food chain of the tissues which were deemed likely to carry high-infectivity titres was a measure which would reduce the potential risk. The Government sought to put this measure in place so far as reasonably practical.

Identification of the high-risk tissues

3.635 The tissues that initially gave cause for concern as high risk were those identified by the Southwood Working Party when making the baby food recommendation. These were identified as high risk by analogy with scrapie on the basis of research work that had been done by Hadlow and others in relation to the pathogenesis of scrapie in sheep. Details of the limited scientific knowledge that existed at the time appear in vol. 2: Science. The research had identified the lymphoreticular system as the main area of pre-clinical infection; hence the fact that the spleen and tonsils were considered to be high-risk tissues.

3.636 The question then arose whether the prevalence of lymphatic tissue required the inclusion in the ban of the intestine and the four stomachs of the cow. This was of some significance, for the intestine was used to make casings for sausages and delicacies such as black pudding and haggis, and the stomachs were the source of edible tripe and rennet, which was used in the manufacture of some cheese.

3.637 In respect of these products, a subsidiary question arose as to whether the manufacturing processes would satisfactorily remove or inactivate lymphatic tissue which might otherwise pose a risk.

3.638 MAFF took the lead in exploring which tissues should be included in the ban. Mr Bradley carried out histological and immunocytochemical studies of the alimentary tract of the cow to determine to what extent lymphatic tissue was present. He also surveyed the processes involved in the production of tripe, rennet and casings. Policy decisions on what should be included in the ban were largely based on his work.

3.639 DH, in the persons of Dr Metters and Dr Pickles, took part in these decisions, however, and independent advice was sought from Dr Kimberlin, Sir Richard Southwood and Dr Tyrrell.

The approach of those involved

3.640 The SBO Regulations were designed to reduce a risk that many who were involved in their preparation believed to be so negligible that no precautionary measures were necessary. This was true of those who believed that in the absence of fresh data, the Southwood risk evaluation and risk management were not open to question, and that the object of the exercise was to reassure the public. We believe that these included Mr Cruickshank, Mr Lowson, Dr Pickles, and Dr Metters. No doubt there were others. As we have recorded, the agreed public presentation of the SBO ban was designed to play down the significance of the ban. We should record that scepticism as to the need for the exercise did not result in any general failure to give careful consideration to how best it should be carried out.

3.641 Thus Dr Pickles told us that if Ministers, for all sorts of good reasons, wished to do something that was not strictly necessary, she would support them. Her attitude was to try very hard to be logical and consistent. Her aim was to ensure that all the bits of offal that might be of concern were removed from the food chain.

3.642 Mr Cruickshank told us that the question was where to draw the line. As to this, he relied on the advice he received from the Veterinary Officers and Mr Meldrum:

The starting-off point was that it was a politically motivated ban, yes, but having got past that point, we looked at it very much in technical terms. We looked at how much infectivity there would be in particular tissues. That was the basis on which we took decisions. ¹

3.643 We shall comment in a little more detail on the process by which decisions were reached on some of the issues involved. In general we wish to commend the diligence with which decisions were reached on the details of the SBO ban. At the same time we would observe that the belief that the SBO Regulations were being imposed as a measure of extreme prudence which went beyond the recommendations of the expert scientists inevitably had an influence when borderline decisions fell to be made. This influence was particularly significant in relation to the consideration to MRM.

The choice of legislation

3.644 The choice of the Food Act 1984 ² as the legislative vehicle for introducing the SBO ban brought with it a statutory obligation to consult those affected. This was bound to result in significant delay in introducing the measure. By this stage BSE had been designated a zoonosis. We raised the question of whether the SBO ban could not, in those circumstances, have been introduced under the Animal Health Act 1981, ³ which would not have imposed a consultation obligation.

3.645 Mrs Attridge informed us that legal advice which MAFF had received at the very highest level ruled out such a course in the absence of stronger evidence of human risk. ⁴ We were not able to follow the logic of this, but did not feel the need to explore the matter further. Regulations requiring the removal of tissues from apparently healthy animals on the ground that a small minority might be incubating a disease that carried a remote possibility of transmission to humans were novel. They were quite complex. They carried serious economic consequences for some. It seems to us that consultation was desirable. The use of the established procedures and mechanisms for dealing with unfit meat under the Meat (Sterilisation and Staining) Regulations 1982 ⁵ was sensible and could conveniently be achieved by subordinate legislation under the Food Act. For these reasons, we have concluded that the decision to proceed under this statute was not merely reasonable, but the appropriate course.

Delay

3.646 Approximately five months elapsed between the decision to introduce the SBO ban and the implementation of that decision. On the face of it, such a delay does not seem acceptable in relation to an important public health measure, albeit one introduced under the precautionary principle in respect of a risk which was considered remote. Mr James Coe, MAFF's Head of Information in 1989, was certainly aware of this. When Mr Cruickshank proposed that the issue of the consultation letter should be accompanied by a press release, Mr Coe advised:

I don't think we should issue a press notice. The media - and public - think we have carried out the ban. If we now announce that we are still talking about it we could get a caning. The press does not understand the niceties of consultation. ⁶

3.647 His advice was endorsed by Mr Thompson.

3.648 The consequence was that in September the Observer published an article which criticised MAFF not only for the delay but for concealing the delay from the public, so that: 'Beef brains and offal, which could contain the agent for BSE (bovine spongiform encephalopathy) are widely used in pies and pâtés, although the public is largely unaware of it.' ⁷

3.649 There is a lesson to be learned here about public relations, but we have concluded that neither MAFF nor DH is to be criticised for the time taken to introduce the SBO ban. The consultation process had to focus on the offal to be banned. It was reasonable, in the first instance, to seek to identify all of these before the consultation letter was sent out, rather than to envisage a two-stage consultation process. When the task of resolving issues about tripe and casings proved more difficult than anticipated, the consultation letter was sent out without further delay. The period allowed for consultation was no more than reasonable, having been extended from 30 August to 13 September at the request of Mr MacGregor. ⁸ The entire period between June and November was one of continuous and diligent activity on the part of those involved in the introduction of the ban, not least Mr Bradley and those responsible for drafting the Regulations.

3.650 Had the technical problems in preparing the Regulations been foreseen, an alternative course might have been adopted which would have resulted in swifter introduction of the ban. This is to use hindsight. Having regard to the situation as it appeared at the time, the response of those involved was adequate - at least in so far as speed of action is concerned. We turn now to consider the individual decisions that were taken.

Tripe and rennet

3.651 It is convenient to consider these together, for a critical issue in the case of each was the status of the abomasum, the fourth stomach of the cow. The abomasum is the source of rennet. It is also the source of a category of tripe: black tripe. It was the only stomach that gave rise to cause for concern in relation to the presence of lymphatic tissue.

3.652 The question whether the four stomachs of the cow, from which tripe was derived, should be banned was first raised by Sir Donald Acheson. ⁹ Initial enquiries indicated that the stomachs were likely to contain lymphoid tissue that would not necessarily be removed in the processing of tripe so that the matter called for detailed consideration. In the meantime it was decided to consult on the basis that the banned offal would include tripe. ¹⁰

3.653 In his report of 13 July, Mr Bradley drew a distinction between the abomasum and the other three stomachs. As to the latter, he was satisfied that procedural changes in the preparation of tripe would enable tripe from these sources to continue to be consumed without risk. ¹¹ He thought, however, that abomasum should not be used for human consumption until it was proven that the dressing procedure removed the mucous membrane lining. ¹²

3.654 After discussion with Mr Bradley about this, Mr Meldrum felt able to advise that in the preparation of black tripe the mucosa was likely to be removed and for that reason abomasum should not represent a human health risk when used for tripe or casings. ¹³

3.655 So far as rennet was concerned, Mr Bradley had suggested that the processing procedures should be studied. ¹⁴ Mr Meldrum was, however, satisfied that for a number of reasons, including the production process, rennet did not present a human health risk. ¹⁵

3.656 Internal minutes show that Dr Pickles and Dr Metters were prepared to accept that tripe posed no risk if the CVL so advised. ¹⁶ However, when they received from Mr Meldrum a detailed account of the position in relation to the abomasum, including the fact that, contrary to his previous understanding, processing did not remove the majority of the lymphatic tissue in the mucosa, ¹⁷ they commented that further studies would be needed. So far as rennet was concerned they were prepared to accept Mr Meldrum's statement, on the basis of information provided to him by the NPU, that pH treatment in the course of processing would significantly reduce any residual infectivity. ¹⁸

3.657 At a meeting with Sir Richard Southwood, Dr Kimberlin and Dr Tyrrell on 18 September it was agreed that both the abomasum and rennet needed further investigation. ¹⁹ New research by Mr Bradley indicated that, although pH would have only a small effect on infectivity, the process of making rennet was likely to result in infectious particles being filtered out as waste. Mr Bradley also suggested the introduction of a less severe criterion for a risk factor test for offal which would draw the line between macroscopically visible lymphoid nodes (within the ban) and lymph tissue only visible microscopically (outside the ban). Under this criterion, abomasum and rennet would not fall within the ban. ²⁰

3.658 When Dr Kimberlin came to advise further on these matters in October his advice followed very similar lines and reached the same conclusions. ²¹

3.659 When the new test, and its consequences, were proposed to Dr Pickles and Dr Metters, they accepted that there was logic in it and that MAFF's recommendations were acceptable from the public health point of view. The object was not to eliminate risk, but to reduce it through all reasonably practical ways. ²²

3.660 The submission to Ministers of 2 November 1989 regarding the proposed Regulations made clear the reasoning behind the recommendation not to ban tripe or rennet and confirmed that this had the approval of the experts. The Ministers accepted the recommendation. ²³

3.661 Had the abomasum been an item of little practical significance, such as the spleen, we think it likely that it would have been included in the ban. Its importance, however, as the source of both tripe and rennet led to a closer scrutiny of the degree of potential risk that it posed. It was concluded that this was not sufficiently significant to justify including it in the ban, and the test of where to draw the line was adjusted accordingly.

3.662 At first blush this story might give the impression that Mr Meldrum and Mr Bradley were primarily motivated by a desire to protect the tripe and rennet industries, and 'moved the goalposts' in order to accommodate the production of these commodities from the abomasum. We have concluded that this is not a fair interpretation of the facts. The process that took place was a bona fide exercise, diligently carried out, to achieve the appropriate balance between reduction of risk and the adverse consequences of the measures to do so. It involved not merely MAFF but also DH and independent experts.

3.663 What the story does illustrate is the difficulty of the task of striking the right balance in the absence of primary data on the infectivity, or lack of it, of the tissues involved. Mr Bradley repeatedly drew attention to the desirability of transmissibility studies and to the restrictions on these posed by shortage of funding and facilities. In the absence of such data, where to 'draw the line' was very much a matter of individual judgement.

3.664 The exercise of that judgement was rendered particularly difficult for those who believed that, because the SBO ban went 'beyond Southwood', the precautionary measures were exceptional steps that went further than science required. This fact was emphasised by Dr Metters in his letter, drafted by Dr Pickles, accepting the revised test. We are inclined to wonder whether Dr Pickles would have been content to accept the revised test had she believed that oral transmissibility was a real risk.

Mesenteric fat

3.665 Careful consideration was given to mesenteric fat. The reasons for excluding it from the ban were spelt out in detail by Mr Meldrum for consideration by Dr Metters and Dr Pickles.

3.666 The comparison with the consideration given to tallow was appropriate. A considered decision had been made that there was no need to include tallow in the ruminant feed ban. That ban was to address a risk of infection that did not involve crossing a species barrier. In these circumstances, it would have been illogical to include mesenteric fat in the SBO ban, which was addressing the remote risk of transmission of infection across a species barrier.

3.667 Mr Maclean acted appropriately both in his initial challenge and his subsequent approval of the recommendation in respect of mesenteric fat.

Casings

3.668 At the meeting with Sir Richard Southwood on 7 June, Mr Meldrum had stated that intestines were used as sausage casings after being thoroughly cleaned. It was inevitable that there would be some lymphatic tissue in the wall of the intestines, but this could be treated as de minimis. However, it was agreed that he would take further advice on the point. ²⁴

3.669 In his letter of 9 June to Mr Clarke, Mr MacGregor stated that because nearly all the lymphatic tissue was removed from intestines before use as sausage casings, he believed that they could be exempted from the ban when used for this purpose. ²⁵

3.670 Dr Pickles viewed this claim with scepticism, as was apparent from her draft reply to Mr MacGregor's letter. ²⁶ Subsequently, in the course of the consideration of the terms of the ban, Dr Pickles reverted to this matter, seeking reassurance that the treatment of casings would preclude contamination with lymphoid tissue. ²⁷ Mr Meldrum responded by saying that as the lymphoid tissue in the mucosa was removed in the course of manufacture, a ban on casings could not be justified 'particularly as the ban itself is purely a precautionary measure going beyond the measures recommended by Southwood'. ²⁸ Subsequently he corrected the statement, after research by Mr Bradley had shown that the processing of casing left a variable retention of lymphoid tissue, a fact that had surprised him. He expressed the conclusion, however, that the risk from casings was extremely small because so little intestinal tissue was used for them, the product was fully cooked and they were usually discarded at the time of eating. ²⁹

3.671 Dr Metters's and Dr Pickles's ultimate agreement to an exemption of casings despite their reservations was, we feel, almost certainly influenced by Dr Pickles's personal view, based on Southwood, that the risk from oral ingestion from asymptomatic animals was so remote that it could be disregarded, even by those who inadvertently ate lymphoid tissues. ³⁰ There are close parallels between this and the tripe and rennet story.

3.672 On this occasion, however, MAFF decided that exclusion of casings could not be justified, which seems to be a clear indication that those involved were seeking to apply objectivity and consistency to the exercise.

The exception for calves under 6 months

3.673 From the outset it had been intended that the ban on spinal cord would not apply to calves slaughtered below the age of 6 months. There was a pragmatic reason why this exception was desirable. Under normal slaughterhouse practice, the carcasses of calves aged less than 6 months were not split in two, so it was not possible to remove the spinal cord unless this practice was changed. However, there were two bases upon which the exception could be justified:

1. Calves under 6 months should not have been exposed to feed containing ruminant protein, since the ruminant feed ban had come into force in July of the previous year.
2. Research in relation to scrapie had indicated that the spread of infectivity would not reach the spinal cord at such an early stage of incubation.

3.674 Mr Meldrum initially advanced the first reason as justification for the proposed exception. ³¹ Mr Bradley pointed out to him that, because of the possibility of maternal transmission, the second reason provided the more cogent justification. ³²

3.675 At the beginning of August, Mr Lowson minuted Mr Cruickshank about a proposal from the CVO to limit the ban on offal from older animals. Initially, this would be from those calves older than 6 months, but could be extended as those born after the ruminant feed ban got older. He suggested two reasons why this was desirable. First, it would ease the problem of disposing of SBO, which renderers were indicating that they would be reluctant to handle. Second, it might serve to avoid pressure in Europe for a total ban on all UK exports of cattle. Countries had a natural reluctance to import animals if some of their tissues were considered to be unsafe for human consumption. ³³

3.676 Mr Lowson's suggestion was met with reservations, both within MAFF and DH. He himself had reservations about recommending it to Ministers unless it was clear that the change of approach would be useful. Mr Hilton and Mr Cruickshank shared these reservations, the latter considering that the risk of maternal transmission would put MAFF in an indefensible position if this course were adopted. The CMO was also concerned about the implications of the possibility of maternal transmission. However, Mr Meldrum disagreed, considering that the evidence that the agent of scrapie was undetectable in young animals could be applied to cattle. ³⁴

3.677 At the meeting with the experts on 18 September, Dr Kimberlin expressed reservations about exempting the lymphoreticular system of young calves. ³⁵ Subsequently, after lengthy discussion with Mr Bradley, he advised Mr Meldrum that he could not find a way of exempting the major LRS tissues at any age, although he appreciated the implications of banning them. ³⁶

3.678 Dr Kimberlin received a copy of Mr Meldrum's letter of 19 October in which he set out in detail the arguments in favour of exempting calves of under 6 months of age from the ban. These led Dr Kimberlin to reconsider his opposition to such a course and to conclude that the potential risk posed by these calves was sufficiently low to permit the exclusion of their tissues from the ban. The factors which influenced him were that it was unlikely that calves would be infected from feed and that it was uncertain to what extent they might acquire BSE by maternal transmission. Furthermore, the infectivity titre of LRS tissues in any young calves that were infected would be low. Dr Kimberlin was not overly concerned about the thymus, because evidence suggested that thymus presented a lower risk than other LRS tissue in natural cases of scrapie. Finally, Mr Meldrum had informed him that the spleen and thymus were not used for human consumption.

3.679 Mr Meldrum's arguments in respect of young calves were also accepted by Sir Richard Southwood and Dr Tyrrell. The exemption was approved by Dr Metters and Dr Pickles.

3.680 The submission to Ministers of 2 November 1989 included the information provided by MILG that there was no knowledge among the trade organisations nor abattoir owners, of use made of any specified offal from calves in the UK, with the exception of thymus used exceptionally as a delicacy. ³⁷ Calves under 6 months would also not have been fed ruminant feed. The Ministers approved the exemption for calves under 6 months.

3.681 Features of this story caused us concern. The approval of independent advisers and of Dr Metters and Dr Pickles appears to have been obtained on the basis that the calf offal types that were exempted were not eaten in the UK. However, although only 25,000 calves were slaughtered in the UK, this figure contrasts with 250,000 which were exported and then slaughtered at about 6 months of age for veal production. In his letter to Mr Meldrum of 30 October, Dr Metters included the comment, drafted by Dr Pickles, '[y]ou . . . do not comment on human consumption of thymus outside the UK'. ³⁸ If calves' thymus glands fell within the category of high-risk tissues it would have been quite wrong to exclude them from the ban on the basis that the risk was one that did not threaten the British consumer but was exported to those who enjoyed ris de veau on the Continent. In such circumstances, to have sought to disguise the risk by exempting calves from the ban in order to preserve our export market would have been scandalous. We raised our concern with those who were involved in the decision to exempt young calves.

3.682 Dr Kimberlin has made it plain that his ultimate approval of the exemption for young calves was not influenced by considerations of the effect that a ban would have on exports. Nor does the evidence suggest that the inaccurate information that thymus was not eaten in the UK was critical to his change of heart in relation to thymus. He told us that he was not overly concerned about thymus, because it was a lower-risk tissue. Indeed, when the CMO recommended that the ban should be extended to include calves' thymus glands in June 1994, by which time SEAC had been informed that it was eaten in this country, Dr Kimberlin felt unable, on scientific grounds, to defend that decision. ³⁹

3.683 We do not believe that export considerations can have influenced either Sir Richard Southwood or Dr Tyrrell in approving of the exemption for young calves.

3.684 Sir Donald Acheson was initially opposed to the exemption for young calves because of concern about the possibility of maternal transmission. Dr Pickles explained that there were reasons for believing that vertical transmission was less likely to occur in cases of BSE than in scrapie. She went on to mention the importance of exports and commented that there had to be strong justification if calves were not to be exempted. ⁴⁰

3.685 When we discussed this matter with her, she observed:

Can I just . . . remind you about how borderline this subject was? If the feed ban had been effective and there was no vertical transmission, there would be no risk whatsoever from thymus. There was a possibility of vertical transmission. We did not know about it . . . Then the published evidence suggested on the scrapie model you would not get detectable infectivity in thymus at six months in any case, even if there were vertical transmission.

So actually any concern at six months was because of a margin of safety on what the presence of infectivity might be in an animal that was incubating the disease. I think I also reminded you when I spoke earlier about Hadlow's work that out of the nine sheep and the three goats there had only been two positives of low titre in thymus. So thymus was always a very borderline tissue to be included in any case.

. . . I think we were on very shaky grounds to make a major objection at the Department of Health on this particular issue. We did ask for it to be reconsidered if vertical transmission was demonstrated. I think we were aware there were some important commercial reasons why MAFF did not want to include this. ⁴¹

3.686 This evidence indicates that export considerations led Dr Pickles and Dr Metters to conclude that they needed to be on firm ground if they were to persist in objecting to the exemption for young calves. Having regard to the considerations mentioned by Dr Pickles and to the views of the experts, we consider that they acted reasonably in concluding that they should agree to the exemption.

3.687 Mr Meldrum told us that he considered both the protection of exports and the threat that UKRA might decline to handle SBO as factors of importance to be borne in mind when considering the exemption for young calves. These considerations clearly led Mr Meldrum to give particular attention to the possibility of the exemption. Had they led him to seek to downgrade the degree of risk posed by the tissues of young calves without scientific justification, this would have been cause for criticism. In the event the factors identified by Mr Meldrum were endorsed by the independent advisers as justifying the exemption. We do not consider that his enthusiasm for the exemption caused him to overstep the mark.

3.688 Mr Cruickshank drew our attention to the fact that his initial response to the very serious implications of the ban for the export trade was that this could not justify an exemption for young calves. ⁴² The desire to promote exports was not a major factor in his thinking. He subsequently came to support the exemption because 'the veterinary opinion had come round firmly to say that really there was no conceivable risk for animals under six months'. ⁴³

3.689 Sir Derek Andrews summarised the position as follows:

The fact that thymus was used as a delicacy in human consumption in the UK was a point which was considered and is specifically referred to in the submission to the Minister of 2nd November 1989. ⁴⁴ The context in which the discussion of this submission took place at the Minister's meeting of 7th November 1989 ⁴⁵ was that the SBO ban was a measure of extreme prudence; that the risk of transmission to humans was considered remote; that calves of less than six months had not been fed MBM; and that the scientific evidence indicated (from the research in sheep) that calves under the age of six months would not contain the agent. I believe that proper consideration was given to this issue at the time. ⁴⁶

3.690 Mr Maclean submitted a statement which dealt in detail with his reasons for accepting the recommendation of an exemption in respect of the offal of young calves. ⁴⁷ This opened with the statement:

In agreeing to exempt tissues from calves of less than 6 months from the SBO ban I placed commercial considerations, including exports and the practical difficulties of disposal, secondary to the question of human health, both of consumers in the UK and abroad. The decision was taken following full consideration of the advice received from officials and scientific advisors. ⁴⁸

3.691 We are satisfied, on the basis of the facts set out in his statement, that this was indeed the case. Ministers received advice which justified their approval of this exemption.

3.692 In summary, a detailed exploration of our concerns satisfied us that the exemption in respect of the offal of young calves was dealt with reasonably.

Mechanically recovered meat (MRM)

3.693 The introduction of the SBO ban was the first of a number of occasions on which consideration was given to the potential risk posed by MRM. We propose to examine the MRM story in detail, for it proved to be a significant weakness in the precautions to prevent SBO from entering the human food chain.

3.694 Chapter 4 of vol. 13: Industry Processes and Controls describes MRM and the process by which it was produced. The process was applied to bones from which the cuts of meat had already been removed. The process mechanically stripped from those bones the residual scraps of meat and other tissues attaching to them. The resultant slurry was used as an ingredient of low-grade meat products. In 1986 approximately 5 per cent of MRM was derived from cattle bones. By far the most significant source of bovine MRM was the spinal column.

3.695 The audit carried out in May 1997 by the Leatherhead Food Research Association in conjunction with the MLC (see paragraph 3.576) included an investigation into the circumstances in which spinal cord would have reached the consumer before the SBO ban. ⁴⁹ Information was obtained from two major companies. Each had removed spinal cord before the MRM process, but one estimated that prior to 1989 perhaps 25 per cent of spinal columns would have had part of the spinal cord attached at the time of the MRM process. A small proportion of bone-in fore ribs and T-bone steaks reached the consumer - only 15 per cent of these joints were sold bone-in. These might have contained small residual amounts of spinal cord. This evidence indicated that MRM was the route by which most spinal cord was reaching the consumer prior to the SBO ban. Mr Keith Baker, Assistant Chief Veterinary Officer (ACVO) in charge of Meat Hygiene, confirmed that this was the case. ⁵⁰

3.696 On 15 December 1995, the Specified Bovine Offal (Amendment) Order 1995 came into force. This banned the use of the vertebral column of a bovine animal in the recovery of MRM and also banned the use of meat derived in this way for human food. As we explain in Chapter 6, this measure was introduced on the advice of SEAC. The reason for its introduction was the discovery by the State Veterinary Service of a number of instances where slaughterhouses had left small pieces of spinal cord attached to carcasses after dressing. SEAC decided that, until there was full compliance with the requirement to remove the spinal cord, it would be prudent as a precaution to suspend the use of bovine vertebral column in the manufacture of MRM, and its recommendation to this effect was adopted. ⁵¹

3.697 More recently an additional reason has been identified for concern about the practice of extracting MRM from the bovine vertebral column. The autonomic nervous system is linked to the central nervous system at 'junction boxes', consisting of clusters of nerve cells, alongside each vertebral body. These are known as dorsal root ganglia. ⁵² In 1998 the result of pathogenesis experiments showed infectivity in the dorsal root ganglia 32 to 40 months after inoculation. ⁵³ The process of recovering MRM would have stripped out, for use as human food, not merely any residual spinal cord but also the dorsal root ganglia.

3.698 These facts raise the following questions in relation to the introduction of the SBO ban in 1989:

1. Should contamination of MRM with spinal cord have been anticipated when the SBO Regulations were being prepared?
2. Should the possibility that dorsal root ganglia might be high-risk tissue have been appreciated at the time of the preparation of the SBO Regulations?
3. What conclusions should have been reached as to the risk posed by MRM?
4. Was adequate consideration given to MRM when preparing the SBO Regulations?