The aflatoxin B1 content of liver tissue was measured in patients who died from chronic liver disease [hepatocellular carcinoma (HCG) (5), schistosomal liver fibrosis (1), chronic aggressive hepatitis (1)] and compared with fifteen controls who died of motor traffic accidents (10), drowning (1), malnutrition (1), idiopathic cardiomegaly (1) and lung infection (2). Significant levels of aflatoxin B1 were found in hepatocellular carcinoma patients who were also hepatitis B surface antigen (HBsAg) negative. Histology showed HCC arising in macronodular cirrhosis.