Determination of resin and fatty acids in sediments near pulp mill locations

A gas chromatographic method for the determination of resin and fatty acids in sediments is described. In this procedure, the sediment sample was air-dried and soxhlet-extracted with a mixture of acetone--methanol (88:12, v/v) in the presence of hydrochloric acid. The acids extracted were converted into their pentafluorobenzyl esters and were then cleaned up on a deactivated silica gel column. Final analysis was performed on either a DB-17 or a DB-5 capillary column with electron-capture detection. Quantitative recovery was obtained from fortified sediments for all acids except palustric, neoabietic and levopimaric acids. The detection limit of all acids in this method was 0.1 micrograms/g based on 1 g of sample. This procedure has been successfully applied to the monitoring of resin and fatty acids in sediment samples collected in the vicinity of several Canadian pulp mill locations.