Quantitative Determination of Formaldehyde in the Parts Per Hundred Million Concentration Level

A new method has been developed for the determination of trace quantities of formaldehyde and appears to be superior to existing methods. The procedure is based on a modification of Schiff’s test for aldehydes. A mixture of dichlorosulfitomercurate II complex and acid bleached pararosaniline hydrochloride is used as the reagent. In the presence of formaldehyde, a purple color is produced. The method is highly sensitive to formaldehyde and acetaldehyde, simple and does not require concentrated acids. When applied to air pollution studies, the method is virtually free of interferences from higher aldehydes. The paper describes the application of this method to spot sampling of the atmosphere and to continuous atmospheric analysis.