In the past four months a new syndrome has caused more than 100 deaths in Spain. The most striking feature is a toxic-allergic pneumonopathy with respiratory distress and radiological evidence of interstitial (occasionally alveolar) exudation. Other features are fever, headache, nausea, muscular and abdominal pains, rash, hepatosplenomegaly, and eosinophilia; later, thrombotic phenomena and neurological disorders may appear. The epidemic has been traced to ingestion of rapeseed oil, denatured with aniline and containing acetanilide. The syndrome does not resemble intoxication with aniline or acetanilide, and is provisionally ascribed to "oleoanilide", a product formed by reaction of acetanilide with fatty acids.