Abstract
An air sampling and analytical methodology for acrylic acid in air has been developed. The method involves the adsorption of the organic acid on silica gel treated with p-methoxyphenol, followed by desorption with acetone, and gas chromatographic analysis on a glass column (with “on column” capabilities). The methodology is adaptable to the determination of time-weighted average exposures (8 hr) and ceiling concentration measurements provided a 48 liter sample volume is not exceeded. The analysis of acrylic acid is accomplished without interference from propionic acid, acetic acid, ethyl acrylate, and butyl acrylate and the limit of detection with linearity is 33 micrograms per milliliter of acrylic acid which is equivalent to 0.5 ppm in a 48 liter total air volume. This sensitivity is sufficient to measure acrylic acid exposures below the new ACGIH recommended TLV of 10 ppm.(1) The adsorption/desorption of the organic acid is not significantly affected under the conditions of high relative humidities provided the air sampling flow rate is maintained at 100 cc per minute for TWA measurements or 500 cc per minute for fifteen minutes (ceiling measurements). The statistical analysis of the data obtained in the valibation of the air sampling and analytical methodology showed that the coefficient of variation was 8.2% and the systematic error was 5.9%.