The Spectrophotometric Determination of Formaldehyde in Whole Smoke/Eine spektralphotometrische Methode zur Bestimmung von Formaldehyd im Vollrauch von Cigaretten

The quantitative determination of formaldehyde in the gas phase of cigarette smoke does not permit any conclusion about the actual level in whole smoke. This is due to the fact that a Cambridge filter charged with smoke condensate absorbs up to 50 % of the volatile aldehydes from the gas phase. A simple method is presented making possible the estimation of formaldehyde in whole cigarette smoke. The procedure is based on the Hantzsch reaction between formaldehyde, acetylacetone and ammonium ion in an aqueous buffer solution. The reaction product, 3,5-diacetyl1,4-dihydrolutidine, has an absorption maximum at 412 nm and is measured spectrophotometrically. The operations are simple and there are no separation steps required. Reproducibility is excellent and interference by other carbonyl compounds can be neglected. Acetaldehyde in concentrations 10 times higher than formaldehyde interferes to less than 1 %. Different types of cigarettes have been analysed with respect to their delivery of formaldehyde. Values found range from 40 to 90 µg per cigarette. The concentrations found in whole smoke are significantly higher than the values cited in the Iiterature for gas phase formaldehyde