To define reference values of human hepatic bile for sodium, potassium, chloride, calcium, iron, copper, urea, creatinine, phosphate, glucose, bilirubin, cholesterol, protein, bile salts, phospholipids, ammonia, pH, PCO2, bicarbonate and osmolarity, bile was obtained via a T-drain from 12 adult patients who underwent cholecystectomy. Bile of females had a higher cholesterol concentration than that of males. The saturation index, however, was not different in both groups.