Contamination of beef carcasses by spinal cord tissue during splitting C.R. Helps a, * , P. Hindell b , T.J. Hillman a , A.V. Fisher a , H. Anil a , A.C. Knight c , R.T. Whyte c , D.H. O’Niell c , T.G. Knowles a , D.A. Harbour a a Department of Clinical Veterinary Science, University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK b Health and Safety Laboratory, Broad Lane, Sheffield S3 7HQ, UK c Silsoe Research Institute, Wrest Park, Silsoe, Bedford MK45 4HS, UK Received 3 March 2001; received in revised form 10 April 2001; accepted 16 April 2001 Abstract In 1989/90, the use of specified bovine offal (SBO) in human food was banned in the UK. Spinal cord, an SBO material, is now removed from beef carcasses post splitting. More recently, following a European Commission Decision introduced on 1st October 2000, regulations in all EU states require the removal of central nervous system (CNS) material from sheep carcasses over 12 months of age and all cattle carcasses. However, in the majority of abattoirs, carcasses are split using a band saw; this often cuts the spinal cord in half along much of its length. This can obviously lead to potential dissemination of CNS material over the carcass and surrounding area resulting in possible contamination with the bovine spongiform encephalopathy (BSE) infective agent. We have used enzyme-linked immunosorbant assays (ELISAs) to detect CNS-specific glial fibrillary acidic protein (GFAP) and S-100b protein. Both assays show the presence of CNS material on the carcass after splitting with a conventional band saw. This con- tamination was still present after the carcass had been washed or steam-vacuum cleaned. However, significantly less CNS con- tamination was observed on carcasses whose spinal column had been removed by an experimental oval saw prior to splitting. With further engineering development, this new technique should be capable of removing spinal cord with minimal contamination risk. Ó 2002 Elsevier Science Ltd. All rights reserved. Keywords: BSE; vCJD; Spinal cord; Contamination; Experimental oval saw 1. Introduction Variant Creutzfeldt-Jakob disease (vCJD) or sus- pected vCJD has affected 85 people to date in the UK (The National Creutzfeldt-Jakob Disease Surveillance Unit, Edinburgh). It has been shown that the trans- missible agent responsible for this disorder is indis- tinguishable from that found in bovine spongiform encephalopathy (BSE) (Collinge, Sidle, Meads, Ironside, & Hill, 1996; Hill et al., 1997; Scott et al., 1999). This finding reinforces the hypothesis that exposure of hu- mans to the BSE agent, presumably through the diet, is the cause of vCJD (Ironside, 1998; Will et al., 1996). Since the introduction of specified risk material (SRM) regulations, tissues suspected of carrying the BSE infec- tive agent have been banned from the food chain. These tissues include the skull (including the brain and eyes), the tonsils, the spinal cord and the ileum in all EU member states. However, because of the way that cattle are slaughtered it is possible for both brain and spinal cord tissue to contaminate the carcass and, hence, enter the food chain. It has been shown that the use of captive bolt guns to stun cattle causes brain tissue to enter the blood stream and it could, therefore, be disseminated throughout the carcass (Anil et al., 1999; Garland, Bauer, & Bailey, 1996; Schmidt, Hossner, Yemm, & Gould, 1999a). During dressing, beef carcasses are nor- mally split down the vertebral column using a band saw and the cut spinal cord removed from each half of the carcass. Since the cord is often cut along most of its length the possibility exists that central nervous system (CNS) material could be spread over the carcass and the surrounding environment. To address this problem, an experimental saw has been designed to remove a column of vertebral bone encasing the intact spinal cord. In this study, we have quantified the contamination resulting from the use of both saws and have examined the effect * Corresponding author. Tel.: +44-117-928-9242; fax: +44-117-928- 9505. E-mail address: c.r.helps@bristol.ac.uk (C.R. Helps). 0956-7135/02/$ - see front matter Ó 2002 Elsevier Science Ltd. All rights reserved. PII:S0956-7135(01)00040-8 Food Control 13 (2002) 417–423 www.elsevier.com/locate/foodcont