Determination of acrylic acid in air by using diffusion denuder tubes combined with HPLC technique

A procedure for the determination of atmospheric acrylic acid in air at the mu g m(-3) to mg m(-3) level is described. Diffusion-based sampling, desig ned to discriminate gaseous analytes from their particulate counterparts, h as been used. Acrylic acid is collected with an efficiency of >98% in tubul ar denuders coated with sodium hydroxide-barium hydroxide-hydroquinone mono methyl ether, and analyzed by high performance liquid chromatography with U V absorbance detection. The detection limit is 2.9 mu g m(-3) at a flow rat e of 0.5 L min(-1) and 30 min sampling time. A precision (p = 0.95, n = 10) of 7.5% of the overall procedure was achieved at the 100 mu g m(-3) level. Results of laboratory studies concerning the effect of the coating reagent and the relative humidity on the sampling efficiency as well as possible i nterferences, in particular by ozone, and the elimination of these interfer ences are discussed. This method was developed to monitor workplace atmosph eres as well as ambient air in industrial environments.