Field evaluation and automation of a method for the simultaneous determination of nitrogen oxides, aldehydes and ketones in air.

The automation of a method for the simultaneous determination of nitrogen oxides, aldehydes and ketones is explained, and its applicability is shown by means ofseveralfield tests. All components were sampled together using impingers filled with a solution of 2,4-dinitrophenylhydrazine (DNPH). The corresponding derivatives were separated by HPLC and quantified by UV/Visabsorbance at 345 nm. Measurements were also performed with solid sorbents. In order to explore the potential of this recently developed method, field samples were taken from: exhaust from automobiles, gas stoves, candle and cigarette smoke, and ambient airfrom restaurants. The variety of these sources demonstrates the versatility of this technique. The new method was validated in thesefield measurementsfor NO2, NO,formaldehyde, acetaldehyde, acroleine, and acetone in the range of20-100 O00ppbv, 50-100 000 ppbv, lO-15000ppbv, 20-250ppbv, lO-150ppbv, and 1-25ppbv, respectively.