Determination of 5 Nitro-Musks in Soil by Gas Chromatography-Mass Spectrometry with Accelerated Solvent Extraction

About 20 g of soil sample was taken, and appropriate amount of diatomaceous earth was added. After mixing well, the mixture was ground to a flowing sand state, and accelerated solvent extraction was carried out according to the set extraction conditions as follows:the mixed solution of n-hexane and acetone at volume ratio of 1:1 as extraction solvent, the extraction temperature of 100℃, the static extraction time of 5 min, and the static extraction number of 2 times. The extract was collected, and passed through anhydrous sodium sulfate (10.0 g) column for dehydration. The effluent was collected, and blown to 1.0 mL by nitrogen. The solution obtained was passed through the silica gel column activated beforehand, and the effluent was discarded. Elution was made by 7 mL of the mixed solution composed of dichloromethane and n-hexane at volume ratio of 1:9, and the eluate was collected, and blown to nearly 1 mL by nitrogen. After 10.0 μL of 100 mg·L^-1 phenanthrene-d₁₀ internal standard solution was added into the concentrate, the volume of the mixed solution was made up to 1.0 mL by n-hexane for gas chromatograph-mass spectrometer analysis, and internal standard method was used for quantification. It was shown that linear relationships between values of the mass concentration of the 5 nitro-musks (musk ambrette, musk cymene, musk Tibetene, musk xylene and musk ketone) and the peak area ratio of 5 nitro-musks to internal standard were kept in the range of 100-2 000 μg·L^-1, with detection limits (3.143s) ranging from 1.1 μg·kg^-1 to 1.2 μg·kg^-1. Test for recovery was made according to standard addition method, giving recoveries in the range of 74.9%-94.9%, and RSD (n=6) of the determined values ranged from 2.4% to 9.8%. The proposed method was applied to the analysis of soil samples at different depths of the spice factory remediation site and surrounding soil sample, musk ambrette, musk xylene and musk ketone were detected in soil samples at different depths of the spice factory remediation site, and the detection amounts decreased with the increase of soil depth.