Blood was drawn from ten healthy volunteer donors into citrate- phosphate-dextrose adenine (CPDA-1) anticoagulant and placed on the quarantine shelf of the blood bank refrigerator. Plasma glucose, sodium, potassium, chloride, bicarbonate, glutamic-oxaloacetic transaminase, lactate dehydrogenase (LDH) and hemoglobin as well as white cell count, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, whole blood pH, lactate and ammonia were measured on all samples initially and at one, seven, 14, 21, 28, and 35 days of storage at 4 degrees C. Whole blood lactate was analyzed serially on five of the units. The most pronounced changes were seen for glucose, potassium, bicarbonate, lactate, LDH, ammonia, and hemoglobin. Plasma glucose and bicarbonate declined in concentration while potassium, lactate, LDH, ammonia, and hemoglobin rose with storage. As expected, these changes differed little from those found with steroid blood collected in acid-citrate-dextrose or citrate- phosphate-dextrose.