Development and application of methodology for determining 1,2-dibromo-3-chloropropane (DBCP) in ambient air.

A method previously described by Mann et al. for the determination of hexachlorobenzene in air was modified to detect DBCP in air at the level of 0.02 ppb (by volume). The method utilizes Chromosorb 101 as a trapping medium with subsequent analysis of the eluted DBCP by electron capture--gas chromatography. The procedure was tested using air flows of 1 1/min to 5 1/min for sampling periods of 30 min to 3 hr. Recoveries of greater than 90% wer obtained for DBCP levels ranging from 0.07 ppb to 20 ppm. More than 90% of the DBCP stored on Chromosorb 101 at ambient temperature for one month was recovered. A one-half acre field plot was sprayed with DBCP using the drench method. Air samples were taken from the breathing zone of the applicator during the mixing, spraying and clean-up procedures. Air samples were also taken periodically around the perimeter of the plot for up to 7 days after spraying.