Fredericton Regional Laboratory and Department of Laboratory Medicine, Dr. Everett Chalmers Hospital, Fredericton, NB, Canada E3B 5N5
Abstract:
Interest has recently been shown in the use of serum cholinesterase levels as a marker for chronic organophosphate insecticide exposure. Interpretation of the results must, however, take into account both long-term biological and analytical variations. The intraindividual variation of serum cholinesterase activity for 12 laboratory workers was 4.3%. The variation was much smaller than the interindividual variation of the whole population (20%). Based on the homogeneity of the intraindividual variance, it is possible to show the level of minimal decrease in enzyme activity which constitutes a departure from "normal".