Volume 13: Industry Processes and Controls
8. Other industries
Fertilisers
Introduction
The use of bovine material in fertiliser manufacture
Legislative changes and developments in the process post-BSE

Introduction

8.66 Fertilisers, which are used to replenish minerals in soil, are supplied to farms and, to a lesser extent, nurseries and domestic gardeners. The Inquiry's interest in the fertiliser industry lies not in the processes used in its production, but in whether fertilisers with bovine ingredients could be a channel for transmitting the BSE agent to animals or people.

The use of bovine material in fertiliser manufacture

8.67 A number of different ingredients are used in the manufacture of fertilisers, including ammonium nitrate, urea, ammonium sulphate, potash and a variety of phosphate compounds. ¹ At certain times, MBM and bovine blood have also been used. However, according to the Fertiliser Manufacturers' Association, 'a little agricultural fertiliser (less than 0.05 per cent) contained a minimal amount' of MBM. ² Mr Brian Rogers, the Chairman of UKRA, confirmed that MBM was used in fertiliser 'to a very limited extent'. ³

8.68 Some slaughterhouses sold blood or other waste to farmers or contractors for use as fertiliser. This blood from slaughterhouses was sometimes disposed of by spraying on fields. ⁴ This practice is also mentioned in vol. 12: Livestock Farming.

Legislative changes and developments in the process post-BSE

8.69 Following the introduction of the ban on SBO in animal feed in September 1990, sectors of the rendering industry sought alternative uses for SBO and products derived from it (such as MBM). Before November 1991, since there was no prohibition on the use of SBO in or as fertiliser, some renderers that were processing SBO were spreading MBM made from it on their own land as a cheaper option than landfilling. ⁵ It was proposed, particularly by Northern Ireland operators, that MBM derived from SBO might be utilised in fertilisers. ⁶

8.70 However, difficulties were perceived with the use of MBM as fertiliser:

Large scale use of meat meal and bone meal as a fertiliser would cause environmental problems, such as a smell nuisance, particularly after rainfall. Its use as a fertiliser would also increase the contact exposure of cattle and sheep and risk further disease. Unless it could be de-natured, there might also be enforcement problems if the 'fertiliser' were used as a cheap source of animal feed. ⁷

8.71 Concerns were expressed about infection of animals grazing on fertilised land and the safety of crops grown in soil treated with fertiliser that contained SBO. Particular concerns arose regarding:

. . . the possibility of the rendered specified bovine offals being sold for use as a fertiliser or for a top dressing material for pastures on which, for example, cattle might graze. ⁸

8.72 A study by Paul Brown and D Carleton Gajdusek found that it was possible for hamster brain material infected with scrapie at a high titre to remain infective in a soil environment for three years, even though the reduction in titre was over 98 per cent. ⁹ The authors suggested that, based on these results, BSE-infected animals 'be excluded as a source of bone meal in fertilisers'. MAFF considered that even ploughing MBM derived from SBO into arable land would not remove the risks entirely:

Ploughing in the meat and bone meal would not completely eliminate the possibility that vermin or dogs would locate it by smell and dig it up, particularly if pelleted. And it is possible that there might be a change of use of arable land to pasture or that advice is simply ignored and material put directly on pasture land. ¹⁰

8.73 Likewise, at a meeting on 7 March 1991, SEAC advised that 'on balance it would be better not to use material derived from specified offal as fertiliser'. ¹¹ On 10 May SEAC considered the issue again and concluded that 'for the time being' the use of 'any material derived from specified offals' as a fertiliser 'could not be recommended'. ¹²

8.74 The Bovine Spongiform Encephalopathy Order 1991 came into force on6 November 1991. It prohibited the use of MBM made from SBO in feed for any animal, but did not explicitly prohibit its use as a fertiliser. ¹³ Rather, the Order imposed restrictions on movement of SBO-based material, and it was understood that movement licences would be issued only if the material was to be burnt or buried. ¹⁴ It did not prohibit using MBM that was SBO-free as fertiliser, but since such MBM could also be used as pig and poultry feed, there was no incentive to do so.

8.75 Although the practice of using MBM as fertiliser never became widespread, on 19 April 1996 the Fertilisers (Mammalian Meat and Bone Meal) Regulations 1996 came into effect. These prohibited the use of MBM as, or in, fertiliser on agricultural land. ¹⁵ Its use was still permitted in private gardens and greenhouses, where it was felt that there was no risk of grazing animals having access to it.