Gas chromatographic (ECD) determination of anthracene in soil and sediment

Abstract

A rapid and simple method for the determination of anthracene in sediment and soil was developed by using a gas chromatograph equipped with an electron capture detector (GC-ECD). The method was based upon the findings that anthracene and phenanthrene were different in the response to ECD and the stability to sulfuric acid. The procedure is as follows. The sample soil is mixed with potassium hydroxide-ethanol solution and digested under reflux for 3 hours. After cooling to room temperature, the digestion mixture is extracted by n-hexane. Interfering substances are eliminated by Florisil column chromatography. The 1st n-hexane eluate is discarded, and anthracene (plus phenanthrene) is eluted with n-hexane-ethylether (95: 5). Then the eluate is concentrated, and determined for anthracene (plus phenanthrene) by GC-ECD. After elimination of anthracene by shaking the fraction with sulfric acid, the solution is determined for background level by GC-ECD. Anthracene is calculated by subtracting the latter value from the former. Recovery of anthracene from sediment and soil was more than 91%. The detection limit for anthracene was 5ng/g. Mineral soils, volcanic ash soils and marine sediments were analyzed, and anthracene were found in a range from not detectable to 81 ng/g.