DETERMINATION OF VOLATILE ORGANICS IN SEDIMENT AT NANOGRAM-PER-GRAM CONCENTRATIONS BY GAS-CHROMATOGRAPHY

Volatile compounds were stripped from sediment samples and absorbed on cartridges filled with Porapak N. The compounds were eluted from the cartridges with methanol. The eluate was assayed for various organic compounds by gas chromatography with electron-capture and photoionization detection. A detection limit of 7 ng/g for each photoionization-active and 1 ng/g for electron-capturing compound was achieved. Time study experiments showed that, while untreated samples should be analyzed within 7 days after collection, samples stored in methanol could be held for up to 90 days without significant loss of volatile compounds.