Some enquiries into the toxicology of zinc stearate.

At the International Congress of Industrial Medicine in Naples (Noro and Uotila, 1954), it was stated that " the inhalation of zinc stearate dust is known as a cause of pneumonia in children, but its effects in the working environment are not so well known. The authors describe the fatal case of a worker employed for 29 years in a rubber plant. Clinical examination and necropsy showed diffuse fibrosis of the lungs. Histological tests for zinc were positive ". These authors (Uotila and Noro, 1957) have since given some further details of their patient, who was first seen by them in July, 1952, after having spent 29 years as a rubber cutter using zinc stearate powder in his work. From the autumn of 1951 he had increasing dyspnoea on exertion, cough, and much sputum. When examined, his general condition was considered fairly good, he had a desquamative dermatitis, clubbed fingers, and " watch-glass " nails. A radiograph of the chest showed slight thickening of the left pleura diminishing towards the apex; small nodules radiating from the hilum; emphysema on the right side posteriorly; and enlarged hilar shadows that were considered to be vascular and not lymphoid. A diagnosis of