Application Note: Cyanide Concentration Changes In Environmental Water Samples As A Function Of Sample Preservation, And Holding Time

Most cyanide analysis sampling protocols specify preservation of samples at a pH of 12 or higher. Sample preservation is intended to minimize changes in analyte concentration to allow sample storage for up to 14 days prior to analysis. The source of a water sample, sample pretreatment, and the presence of possible matrix interferences must also be considered in determining the appropriate sampling and preservation procedure to avoid inadvertent formation or destruction of cyanide species.