Radiation exposure was studied in 327 patients undergoing endoscopic retrograde cholangiopancreatography, or endoscopic papillotomy taking into account fluoroscopy time and incident area exposure. The mean fluoroscopy time was 238 +/- 152 seconds and the incident area exposure 3,730 +/- 2,790 R X cm2. These results were compared with standard exposures in upper GI series and colon examinations as found in the literature.