Extraction of explosives from soil followed by gas chromatography–mass spectrometry analysis with negative chemical ionization

A new, simple and accurate method for extraction of explosives from soil was developed and validated. The method includes one hour gentle extraction of compounds from soil in acetonitrile:dichloromethane 50:50 at 30 °C. Further analysis was made with GC–MS using cool on-column injection and negative chemical ionization. The method increased the recovery of the more volatile products, generated higher accuracy and was extensively time-saving compared to the conventional EPA (US Environmental Protection Agency) 8330 method. Applications are demonstrated on commercial reference materials.

► A new extraction method for explosives in soil, using GC–MS, worked well for three certified soils.
► High recovery of the analytes, in most cases within the confidence interval of the soils.
► Validation showed no perfect linearity of the GC–MS, but very low curvature, and also low LOD.
► Time-saving and simple extraction in combination with low LOD allows a higher throughput of samples.