The use of hlqh field 1~ n.m.r. to follow the reactlon of aflatoxin B1 with ammonium hydroxide has been investigated. The time course of the formation of aflatoxin D1 and MW206 has been establlshed and a mechanism 1s proposed for the parallel formatlon of the two mayor breakdown products. Srnce the well publiclsed Incident in England, in 1960, when 100,000 turkey poults were affected by the previously unknown "Turkey-X disease",l and the subsequent isolation and characterisation of aflatoxin B1 (1) as the malor mycotoxic contaminant of Brazilian groundnut meal fed to the fowls, there has been consrderable interest in ensurrnq that such cases of toxicosis do not recur. The danger of mycotoxins to man, whether directly through contaminated foods, or indirectly, from the products of animals lnqestlnq mouldy foodstuffs, is such that all necesary steps should be taken to eliminate that risk. While it is sensible to store foodstuffs under condltlons of temperature and humidity that minimise funqal growth, it 1s often the case that the product has been spoiled before harvest, and already contains conslderable amounts of mycotoxin. The detection of mycotoxrns is therefore very Important, and intensive research has resulted rn sensitive methods of quantifying aflatoxrns in a wide range of commodrtles, leadrnq to the settlnq of a 20 ppb llmlt by the US Food and Drug Administration. Once a commodrty has been identified as belnq contaminated beyond a level fit for human or animal consumption, the problem arlses of what to do with It. The removal of mouldy peanuts for example, by electronic sorting methods, 1s an attractive Idea, but the fact that aflatoxins diffuse away from the mycelrum means that residual contamination will remarn. Alternatlvely, aflatoxin contaminated peanuts may be drverted to the production of edible 011, since the process results in an aflatoxin-free product,9 but the toxins remain in the residual meal, whrch 1s still unfit for use as feed. Reductrons in mycotoxin levels are usually achieved durlnq cooking processes, such as the dry roasting of peanuts, or the popping of corn. However, in the case of aflatoxins, the reduction is modest, and the consumer is unlikely to accept a product which has been contaminated at such a late stage. Therefore, a number of chemical methods for treatment of contaminated feeds have been Investigated, and in general it has been found