The half-times of the alpha-hydroxylated intermediates formed during metabolism of diethylnitrosamine and N-nitrosopyrrolidine have been determined. The method for determining half-times involved in vitro enzymatic conversion of the nitrosamine to a hydroxylated intermediate followed by trapping of the alkylating species generated from the chemical decomposition of the intermediate as it flowed through a column containing bound nucleophile. Half-times of less than 1 min at pH 7.4, 37 degrees C, were calculated from the distribution of alkylation on the column and the known flow rate of metabolic intermediates through the column. The half-times may be short enough to significantly limit organ distribution.
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