Congener production in blood samples during preparation and storage.

The possibility of congener production in blood during storage was studied. The material consisted of 216 blood specimens in which ethanol was not detected. We divided the specimens into two groups, A and B. Group A: 97 specimens were stored at 4 degrees C until alcohol analysis, and only exposed shortly to room temperature during the aseptic preparation for analysis. Group B: 119 specimens were stored at 17 degrees C until alcohol analysis were performed, and the handling during preparation was not aseptic. All specimens were subsequently stored at 4 degrees C. After three to twelve months of storage the blood specimens were analyzed for congeners. None of the forensic important congeners (n-propanol, isobutanol, or butanol-2) were detected in Group A, whereas in Group B n-propanol was detected in fourteen of the specimens, isobutanol in sixteen, and butanol-2 in two specimens.