The occurrence of notable cases of ill health, typically involving cognitive dysfunction and other neurological disorders, among pilots flying jet and turboprop aircraft and cabin crew working on such aircraft [1], has led to the proposition of "aerotoxic syndrome" [2], meaning the complex of disorders, mainly neurological, observed in people whose anamnesis includes frequent flying. It is proposed that the chain of causality ("diagram of immediate effects") shown in Scheme 1 exists. 1