Volume 6: Human Health, 1989-96
3. Introduction of the ban on Specified Bovine Offal
Preparation of the SBO Regulations
Mesenteric fat
Casings

Mesenteric fat

Mesenteric fat issue raised during consultation

3.462 The question of mesenteric fat was first raised on 25 September in the MILG response to MAFF's consultation document. They noted:

The Ministry's consultation paper does not make clear whether the mesenteric fat, which is attached to the intestines, is affected by your proposals or not. We need to know whether this fat can still be used for human consumption. A ban would mean a significant loss of revenue to the abattoirs. ¹

MAFF's response

3.463 Mr Maslin's note of the meeting on 27 September - to discuss the responses to the consultation - recorded the following:

Mesenteric fat was a valuable by-product used in making tallow and edible fats. It did however contain lymphatic tissue. If the ban was extended to cover it there would be a serious effect on the industry through loss of income. There would also be additional disposal problems. It was agreed that the production process made fat and tallow a low risk product and that the ban should exclude mesenteric fat. ²

3.464 Consequently, it was noted that the definition of intestines should make it clear that it did not cover mesenteric fat.

DH's response

3.465 On 3 October, when Mr Lawrence sent Dr Pickles the note of the 27 September meeting, he drew her attention to mesenteric fat:

The material is currently rendered to produce tallow and edible fats. The view taken at the meeting was that even though mesenteric fat contains lymphatic tissue, the fact that the majority of it is removed during preparation for processing, plus the rendering process itself, ensures that it is a low risk and should not therefore be proscribed. However I shall be grateful for confirmation that your Department takes the same view on this. ³

3.466 Dr Metters had been sent a copy of the letter and suggested to Dr Pickles that 'it is surely the lymphatic vessels that present a problem'. However, he was not familiar with the number and distribution of lymph nodes in bovine mesentery, and asked whether they needed more detail from MAFF. Dr Pickles responded that she had already requested more information. ⁴

Rationale for excluding mesenteric fat from the SBO ban

3.467 Mr Lawrence also updated Mr Gummer on 3 October about MAFF's conclusions following the consultation process. He noted that mesenteric fat should not be covered by the ban, since the way it was prepared and processed minimised the risk of transmission. ⁵

3.468 Mr Meldrum's letter of 19 October also provided Dr Metters with further explanation as to why MAFF had decided to exclude mesenteric fat from the SBO ban. Mr Meldrum explained that 60-70 per cent of the fat was obtained from the gut room after the intestine had been flushed and washed with water. It would be included with material to be rendered for human consumption. The majority of the fat would be held at high temperature for 15 to 20 minutes, so that the material would separate. The fat would be held in vats for preparation of dripping, while greaves containing the solid fraction would not be used for human consumption. Mr Meldrum continued:

Quite clearly the agent of BSE might be present in the mesenteric lymph nodes although in the first place one would have to assess whether or not this risk is greater than the risk from the lymph glands present in the carcass which are not to be subjected to the offal ban. In addition, the weight of lymph nodes in the uncooked material would be very low compared with the overall weight of the mix. In addition, and most importantly, we know that the agent of BSE is associated with lipo protein and these proteins would fractionate with the greaves.

As you may be aware, this is an identical process to that used in the animal protein processing industry for the preparation of meat and bone meal and tallow for industrial purposes. We have taken the view supported by the Southwood Committee that such fat is not a risk to animal health and should not therefore be part of the ruminant protein ban.

On the basis that any lymphoid tissue is only a small fraction of the material harvested, is heated to 115 to 120°C, that the agent of BSE would fractionate with the lipo protein into the greaves and that therefore there will be a very low level of the agent in the dripping, I recommend that bovine fat should be excluded from our proposed offal ban. ⁶

3.469 Dr Metters replied to Mr Meldrum: 'we agree that it would be illogical to ban mesenteric fat for human consumption. The amount of BSE agent in contaminated lymph nodes is likely to be small and unlikely to survive processing.' ⁷

Ministers decide to exclude mesenteric fat

3.470 In his covering submission to the final draft regulations on 2 November, Mr Lawrence proposed that mesenteric fat, used to produce tallow and edible fats, would not be included in the ban. ⁸

3.471 At the subsequent meeting of MAFF Ministers and officials on 7 November, concern was expressed about the proposed exclusion of mesenteric fat from the ban. ⁹ According to the note of the meeting, it was agreed to exclude mesenteric fat after:

Mr Meldrum explained that the risk associated with mesenteric fat, while not zero, was extremely minimal. In response to questions from the Parliamentary Secretary, he confirmed that non-mesenteric fat that might be used for human consumption did not contain lymph nodes and did not pose a problem, and that mesenteric fat, which did contain them, would not be found in association with other organs, such as liver and kidneys, used for human consumption. ¹⁰

3.472 In a statement to the Inquiry, Mr Maclean explained that his query about mesenteric fat 'was typical of the sort of question put to officials by Ministers; it was essential, I felt, that if there were to be any exclusions of this type Ministers understood the reasons for such exclusions'. ¹¹ During oral evidence, Mr Maclean told us that he had flagged his concerns prior to the meeting, and:

. . . to be absolutely honest I flagged up mesenteric fat and wanted further questions on it because I had never heard of the term before. I wanted to be sure, if I was being asked to exclude mesenteric fat, I had a clue what it was. ¹²

Casings

MAFF's formulation of the casing exception

3.473 In his advice to Mr Thompson on 22 May 1989 about the Minister's cull cow proposal (see paragraph 3.204), Mr Lawrence noted that the BMMA had informed MAFF that some intestines were used for sausage casings. However, 'the mucosal surface, including lymphatic tissue (which might harbour the agent) is removed before use and they are salted as well'. Mr Lawrence concluded that such materials 'must be considered as a very low risk indeed'. ¹³

3.474 In his 2 June note (see paragraphs 3.235-3.239) Mr Cockbill told Mr MacGregor that while most potentially infective offal was not used in meat products, the major exception was intestines, which were used as sausage skins. Though alternative casings were available, 'a ban on this use of offal would have a significant effect on the meat products trade and could lead to pressure for scientific justification for such action'. ¹⁴

3.475 The note therefore recommended that if a ban was to be implemented, the use of SBO in sausage casings should be an exception to the general ban on the use of SBO in meat products intended for human consumption. ¹⁵

3.476 When Mr MacGregor and senior MAFF officials met on 6 June to discuss the note it was agreed that intestines used for sausage casings did not pose a problem since they were thoroughly scraped and cleaned before use. However, Mr MacGregor asked that the experts look carefully at the position on casings. ¹⁶

3.477 The minute of the meeting on 7 June between Mr MacGregor, MAFF officials and Sir Richard Southwood, records that:

Mr Meldrum pointed out that intestines were used as sausage casings after being thoroughly cleaned, but it was inevitable that there would be some lymphatic tissue in the wall of the intestines. He thought this could be regarded as de minimus. Kimberlin had done some work on intestines although it was not clear that this covered stripped casings. It was agreed that Mr Meldrum should take further advice on the casings point. It was however thought that the advice would be that there was a minimal risk only with these. ¹⁷

3.478 Thus, when Mr MacGregor wrote to Mr Kenneth Clarke on 9 June proposing an SBO ban, he said:

. . . because nearly all of the lymphatic tissue (which may harbour the agent) is removed from intestines before use as sausage casings I believe that they can be exempted from this prohibition, when used for this purpose. ¹⁸

DH's response

3.479 Dr Pickles drafted a reply to Mr MacGregor for Mr Clarke on 12 June. Among other things, it stated:

I presume your experts have confirmed that stripped intestines contain so little lymphatic tissue that their exclusion from the ban does not appear anomalous and liable to become the subject for further public criticism. ¹⁹

3.480 However, Dr Metters's version, drafted at the request of Sir Donald Acheson and subsequently sent to Mr MacGregor, did not mention intestines. ²⁰

3.481 On 14 June 1989, the day after the public announcement of the SBO ban, Dr Pickles commented to Dr Metters and other DH officials that 'it is not clear what is to be proposed for intestines'. ²¹

15 June: Mr Fry circulates draft instructions to lawyers for the preparation of Regulations to implement the SBO ban

3.482 In his draft instructions to lawyers, Mr Fry explained which types of offal the ban should cover. However, he noted that 'exceptions would have to be made for intestines which are cleaned to remove the lymphatic tissue for use as sausage casings'. ²²

DH's reaction to the draft consultation letter

3.483 Dr Pickles minuted Mr Maslin on 7 July to express her reservations about the draft consultation document. She stated:

. . . as it is currently worded it looks as if sausage casings are a risk but you are excluding them from the ban because it would otherwise be inconvenient/expensive. I presume MAFF is content that whatever treatment is given to small intestines to prepare casings means that there is no remaining contamination with lymphoid tissue. Unless you can give me that reassurance, a 'risk' must remain. Whilst you know that I am not myself persuaded this risk is one we need take action about, the inconsistency with the other steps you are taking cannot be disguised. ²³

3.484 The same day Mr Maslin forwarded a copy of the revised draft consultation letter and submission to Mr Cruickshank, and commented in his accompanying minute that:

I understand from Meat Hygiene Division that the removal of lymphatic tissue for small intestines intended for sausages takes place either at the slaughterhouse or the sausage factory. I have amended the draft to reflect this but it does leave the question of enforcement. I assume however that the movement licence could cover this by making it clear that, if not already processed, the sausage manufacturer would have to do so before they are used . . .

Dr Pickles, DH, has commented that she does not believe casings should be exempted. I am not sure however whether this is the official Department of Health view or her own. We are trying to contact our opposite numbers to find out. ²⁴

3.485 The reworked consultation document stated that there would be an exemption for:

. . . that part of the the small intestines of bovine animals used for casings for sausages if it is cleaned immediately after slaughter, so as to remove lymphatic tissue. ²⁵

3.486 Dr Pickles minuted Sir Donald Acheson on 17 July, saying she was still concerned about sausage casings made from bovine small intestine. Though MAFF claimed that all the lymphoid tissue was stripped in its preparation, 'I have been asking to see that in writing for some time, to no avail.' ²⁶

3.487 The next day Dr Metters was informed of the results of histopathological examinations of bovine gastrointestinal tissues carried out by the CVL. Dr Metters conveyed the information to Dr Pickles on 19 July. The CVL had been asked to investigate the lymphoid constituents of bovine intestines that had been stripped of endothelium prior to their use as sausage casings. They had done so, and found that the stripped casings contained minimal lymphoid tissue. Since the casings were also processed before use, the CVL had concluded that the BSE risk to humans from intestines used as sausage casings was minimal. Dr Metters also told Dr Pickles that:

I reminded him that Mr MacGregor had asked MAFF officials (not DH) to investigate the lymphoid content of bovine intestine, as used for human consumption. If MAFF were satisfied with the findings from CVL, DH would certainly not wish to second-guess their findings. ²⁷

3.488 The revised consultation document submitted to Mr Thompson on 19 July said, regarding intestines:

There would also be an exemption for the large and small intestines of bovine animals used for casings for sausages, provided they are processed (either in the slaughterhouse or in casing manufacturers' premises) to remove lymphatic tissues. ²⁸

3.489 On 21 July Dr Pickles forwarded a copy of the consultation letter to Sir Donald Acheson and Dr Metters and noted she was now 'content' with MAFF's proposals. ²⁹ In particular, she noted intestines were only to be allowed as sausage casings if the lymphatic tissue was removed. ³⁰

3.490 Three days later Mr Meldrum wrote to Dr Metters, providing the written confirmation that Dr Pickles had been seeking for some time:

The intestines contain significant amounts of lymphoid tissue and are thus a 'risk' organ. However in the processing of casings for sausage manufacture the lymphoid tissue in the mucosa is removed when the intestines are scraped, cleaned and washed. On this basis we have concluded that we could not justify a ban on intestines so processed for use as casings; particularly as the ban itself is purely a precautionary measure going beyond the measures recommended by Southwood. ³¹

3.491 Dr Metters replied on 3 August, noting the points Mr Meldrum had made on intestines used for sausage manufacture. ³²

3.492 On 7 September, Dr Pickles minuted Mr Maslin regarding a statement by a medicinal company which used bovine intestines from the UK, which said that there was no way of physically separating the serosal layer from the lymphatic tissue in intestines. She noted:

These statements seem inconsistent with what has been said in justification for the exclusion of sausage casings from the proposed offal ban. The statements made by the licence holder are of course confidential under the Medicines Act, but inevitably there is a risk that the advice they have received might become public.

As you know, my personal view is to be relaxed about this since my own inclination would be to back the Southwood view and regard the risk from oral ingestion from asymptomatic animals to be so remote it can be disregarded, even for those who do inadvertently eat lymphoid tissue. But you may wish to take this up in considering the responses to your consultation letter and in defensive briefing of your Ministers for the future. For my own part, my scientific curiosity would like to be satisfied as to whether or not lymphoid can be separated out. ³³

18 September: the ad hoc meeting of experts

3.493 At the meeting it was noted that intestines had been sectioned and lymphoid tissue was found to be virtually absent. Processing, including scraping and turning the tissue inside out helped ensure this. Thus, it was agreed that casings could be excluded from the ban if histological examination confirmed the absence of lymphoid tissue. Mr Bradley would carry out the examination in the next two weeks. ³⁴

3.494 Dr Kimberlin, who was also preparing a report on abomasum and rennet (see paragraphs 3.450-3.452) would also consider the issue of casings in his report, although this was not recorded in the note of the meeting. ³⁵

Consultation responses on the casings exemption

3.495 Issues relevant to the casings exemption, raised in response to the consultation document included:

1. The British Medical Association questioned whether sufficient research had been carried out into the effectiveness of stripping lymphatic tissue from large and small intestines, prior to their use for sausage casings. There was concern that if this was a simple mechanical process, a danger might exist that viral tissue might still be present adhering to the intestinal walls; ³⁶
2. The Institution of Environmental Health Officers (IEHO) suggested that an overall ban on intestines would be more appropriate. This would also remove problems associated with the processing to remove lymphatic tissue, which was the real problem; ³⁷
3. UKASTA noted that there seemed to be a lack of control over disposal of lymphatic material; ³⁸
4. The Sterilised Suture Manufacturers Association queried how the removal of lymphatic material was to be carried out; ³⁹ and
5. The Royal Environmental Health Institute of Scotland raised enforcement problems, and suggested it should be mandatory to process the intestine in the slaughterhouse of origin. ⁴⁰

3.496 At the 27 September meeting to discuss the responses it was noted, in relation to casings, that further scientific studies were being conducted and a decision would be made once the results were available. ⁴¹

3.497 Also on 27 September, Mr Bradley minuted Mr Wilesmith and Mr Maslin with his views on the consultation responses. He noted that sausage casings had been a 'bone of contention', but he thought the issues would 'all be resolved scientifically by next week when my study is complete'. ⁴²

3.498 On 3 October, Mr Lawrence updated Mr Gummer on the proposed ban noting that there would be additional responsibilities for local authorities in overseeing controls at sausage casing manufacturers, although these were 'unlikely to be of great significance'. ⁴³ Mr Lawrence concluded that when the further studies on casings were completed, further discussions would be held with DH and possibly outside experts, and a submission would be prepared for the Minister. ⁴⁴

3.499 Mr Lawrence's letter of the same day to Dr Pickles, in which he forwarded a note summarising conclusions of the meeting of 27 September, advised that MAFF would wish to discuss Mr Bradley's and Dr Kimberlin's reports on casings when they became available. ⁴⁵

Mr Bradley's report on bovine casings

3.500 Mr Bradley reported to Mr Meldrum and Dr Watson on 6 October. He explained that intestine divided into approximately equal halves had been collected from ten adult cattle slaughtered and passed for human consumption. Each half had been processed to the casing stage within about four hours of death. Samples were then collected for histological examination from different intervals along the halves. ⁴⁶

3.501 Mr Bradley gave technical details of the results obtained, and concluded as follows:

This study reveals that prepared bovine casings consist consistently of serosa, muscularis, sub-mucosa and muscularis mucosae and rarely mucosa. As a result some Peyer's patches, lymphoid nodules and infiltrating lymphocytes remain.

There is thus a probable increased risk of BSE infectivity in prepared casings which is probably not further reduced by either physical (heat) or chemical (salt) processes used in manufacture.

Consumers may be protected to some degree due to cooking processes and by not eating the casing.

The precise risk factors in regard to BSE infectivity can be estimated by assay in mice and it is recommended this is done. Further expert opinion should be sought on the interim decision needed now on the basis of the scientific evidence and in the light of Professor Southwood's report stating the risk for humans was remote. ⁴⁷

19 October: Mr Meldrum writes to Dr Jeremy Metters

3.502 Mr Meldrum's letter of 19 October to Dr Metters noted that 'there is no dispute that both small intestines and large intestines should be covered by the ban' and that Dr Kimberlin's report had reached the same conclusion. On casings, he quoted Mr Bradley's report at some length, and then said:

I might add that I am somewhat surprised that so much tissue remained in the casings but this may be a feature of casings obtained from cattle as against pigs. ⁴⁸

3.503 Mr Meldrum noted that Mr Bradley's findings indicated that a risk of BSE infectivity must exist if it is present in the first place in gut-associated lymphoid tissue. However, he concluded:

Nevertheless such casings are only used in black and white puddings, are cooked and are normally discarded at the time of eating. In addition, the vast majority of bovine intestines are discarded in toto and there is only limited utilisation of bovine casings for human consumption and this constitutes a further dilution factor.

We conclude that the human health risk from casings is extremely low particularly in view of the fact that so little intestinal tissue is used for casings, that the product is fully cooked and we believe that it is common practice for the casings to be discarded on the table. ⁴⁹

3.504 Mr Meldrum forwarded a copy of his letter to Sir Richard Southwood and Dr Tyrrell four days later, and asked for their views. He commented that Dr Metters was 'broadly content but will be giving me his final view later this week'. ⁵⁰

3.505 Sir Richard responded that he was 'perfectly content' with Mr Meldrum's recommendations. ⁵¹ Dr Tyrrell responded that 'on balance it is reasonable to exempt casings provided that it is on the basis that the policy is to reduce the risk of oral ingestion of BSE-contaminated material, which is probably very small to one which is very small indeed'. ⁵²

30 October: DH recommends MAFF to proceed as it thinks fit with the proposals

3.506 In his reply of 30 October to Mr Meldrum's letter, Dr Metters said that DH was

. . . content with the logic of your arguments on all tissues except sausage casings. For these we still wonder about the possibility of using synthetic alternatives, particularly as so little bovine offal is used for this purpose. However, we are content for MAFF to proceed as they think fit in the light of the above comments. ⁵³

3.507 Dr Pickles had drafted the letter for Dr Metters. In a note attached to her draft reply she commented that:

I am persuaded by their arguments on 3 of the 4 points. The remaining one on casings, whilst as you know my own belief is that this whole exercise is hard to justify, suffers from inconsistency. I provide a draft reply on this basis but would not object if you acquiesced with the MAFF line on this one too. ⁵⁴

MAFF changes its view on the exemption of casings

3.508 In the light of this response from DH, MAFF changed its view on the proposed exemption of casings. On 30 October, before receipt of the DH's views, Mr Lawrence circulated a draft submission to Mr Meldrum, Mr Cruickshank and other MAFF colleagues. The covering note indicated that the recommendations given in the draft submission had been included on the assumption that DH had endorsed them. The reasons given in the draft submission for the exemption of casings were as follows:

Both small and large intestine contain lymphoid tissue. Even after processing there is a definite but variable retention of lymphoid tissue in the form of Peyer's patches, nodules and infiltrations, though all are, in some cases, almost totally reduced by the processing procedure. Nonetheless, such casings are only used in black and white puddings and once cooked are normally discarded before consumption. It is therefore concluded that the human health risk from casings is very low indeed, in view of the processing method and the fact that the product is fully cooked and the skin not eaten. ⁵⁵

3.509 However, the final submission sent to Mr Gummer on 2 November, recommended:

Although such casings are only used in black and white puddings and once cooked are normally discarded before consumption, it is considered that, as an ultra-precautionary measure, such material should not continue to be available for use as casings. The Department of Health endorse this view. ⁵⁶

Mr Meldrum explains the change in position

3.510 Mr Meldrum wrote to Dr Metters on 7 November to explain the situation regarding casings. He said:

I have reconsidered our position on the use of bovine casings and in view of your reservations we are now recommending to Ministers that bovine casings should also be banned for human consumption. I believe it is most important that we have a fully agreed position on this most important area. In addition, it will make it easier presentationally to ban all small and large intestines derived from cattle. However, I trust that this will not cause you any problems with the use of sutures. No doubt we shall have some complaints from the producers of haggis and black and white sausages but we can live with that since there are alternative materials that can be used. ⁵⁷

7 November: Ministers agree to include casings in the ban

3.511 At the meeting of MAFF Ministers and officials on 7 November it was agreed that intestinal material used for casings should be included in the ban. ⁵⁸

Reaction to the inclusion of casings in the ban

3.512 Following the decision that casings would now be included, Mr Maslin made urgent contact with the main trade organisations to inform them of the change and to seek their immediate reactions. Mr Maslin recorded the responses in a minute, which included the following:

1. The BMMA reported that little usage was made of bovine casings from the UK, and they were not overly concerned about the ban;
2. The National Federation of Meat Traders said the ban would have an affect on their trade, but alternatives were available. They could not understand why processed casings were to be banned yet lymph nodes in meat were not; and
3. Various manufacturers and retailers were concerned about the financial implications. While alternatives were available, the quality was not as good. ⁵⁹

3.513 In his statement to the Inquiry Mr Maslin commented that subsequent calls from companies affected by the ban on casings revealed that some firms would be seriously affected, and job losses were expected. Companies were also unhappy about the lack of proper consultation on the change. ⁶⁰

3.514 When Ms Bronwen Jones submitted the Regulations to the Minister for his signature on 8 November 1989, she attached a note stating the following about casings:

There is however one particular issue of which the Minister should be aware. As the Minister knows the Regulations would prohibit the use of bovine intestines as casings. This prohibition was included after the formal consultation process had been completed, and officials therefore telephoned bodies representing those likely to be affected to seek their views. The industry (both suppliers and users of casings) were not happy with this change and said that it would pose difficulties for the manufacturers of saveloys, black and white puddings and haggis, and impose additional costs on slaughterhouses, who will be unable to sell this material for casings. They also questioned the scientific basis for this decision. Users are concerned about casings which they have in stock at the time the Regulations come into force. Against this, it must be said that consumer interests, if similarly consulted, would no doubt have been as strongly in favour of the ban on casings.

Although none have expressly said that they regarded consultation at such short notice, by telephone, as unacceptable, it is clear that this could be a point of criticism, and expose us to legal challenge on the validity of the Regulations. ⁶¹