Cereal Chem 40:66 - 70.  |  VIEW ARTICLE

Determination of Chromium and Lead in Periodic Acid Solution and Dialdehyde Starch.

L. T. Black, E. B. Lancaster, and H. G. Maister. Copyright 1963 by the American Association of Cereal Chemists, Inc. 

Two existing methods have been improved and adapted for the determination of chromium and lead in either periodic acid oxidant solution or dialdehyde starch. Because a periodic acid solution destroys color- producing reagents by oxidation, a procedure was developed to remove all the periodic acid before analyses were carried out. The intensity of the colors produced by the different reagents was measured in a spectrophotometer. A standard solution of dichromate gave a least-squares slope of 2.02 p.p.m. per absorbance unit with a standard deviation from regression of 0.028. Lead gave a slope of 3.57 p.p.m. per absorbance unit with a standard deviation from regression of 0.048.