The existence of a relationship between upper digestive tract impairment and respiratory disturbance is generally accepted. The aim of this study was to determine whether pulmonary aspiration, documented by labeled meal and lung scans, could be a contributory factor. Thirty-two patients with chronic respiratory complaints (19 men, 13 women, mean age: 57.8 yr), 29 of whom had an FEV1 below 80 percent of predicted values, and 13 healthy subjects (six men, seven women, mean age 50.9 yr) took part in a prospective study. Scintiscans showed gastroesophageal reflux (GER) in 27 patients (84 percent) and in five control subjects (38 percent). Lung contamination was ascertained in 24 patients (75 percent) and in two control subjects (15 percent) (p less than 0.001) 15 hours after a labeled solid meal. Vegetal fibers were found in sputum smears after mouth rinsing the day after ingestion of 8.5 g wheat bran in 72 percent of patients and in 77 percent of control subjects. Although two associated phenomena are not necessarily causally related, pulmonary aspiration documented by pulmonary scintigraphy did significantly correlate with gastroesophageal reflux, suggesting that aspiration resulting from reflux may perpetuate, if not initiate, chronic bronchial disease.