In May 1981 a new disease caused by widespread food-poisoning (probably with adulterated rape-seed oil) appeared in Spain. More than 20000 people were affected, and about 350 patients have died. The clinical syndrome consisted of pulmonary, neuromuscular and systemic symptoms, which evolved to produce mild or severe physical disabilities. Although the disease is not primarily a psychiatric condition, more than 6000 TOS patients have been referred to a psychiatrist: these patients show a well-defined ‘reactive disaster syndrome’, vulnerability being associated with female sex, low income and class, and a personal history of ‘nervous' disorders. The enormous public repercussions of the disease and the specific administrative measures it provoked are discussed and evaluated. This unique experience of a specific disaster can contribute to our knowledge of the psychological and psychiatric aspects of disasters in general; and it suggests that teams of psychologists and psychiatrists should play a significant role in managing the effects of major catastrophes.