Determination of hexabromocyclododecane in soil by supercritical fluid extraction and gas chromatography mass spectrometry

Abstract

A method using supercritical fluid extraction (SFE) and gas chromatography (GC) mass spectrometry (MS) was established to analyze hexabromocyclododecane (HBCD), a brominated flame retardant, in soil. The HBCD spiked in simulated soil was extracted by SFE with optimized operating parameters and GC-MS/LC-MS was employed to detect the target analyte. The experimental results indicated that the optimum extraction conditions were 50 °C, 25 MPa, and 6 min static and 18 min dynamic extraction with 20% (v/v) modified ethanol–2% Triton X-114. The highest extraction efficiency of HBCD with optimal parameters could reach 98.9%. The differences among Soxhlet extraction, ultrasonic-assisted extraction and SFE were investigated. In comparison with other extraction methods, SFE could not only improve the extraction efficiency and shorten the extraction time but could also easily remove the extracted impurities. Furthermore, the established analytical method was applied to detect HBCD in field soils and the average concentration in real soil samples was 0.96 mg kg⁻¹. This work provides an efficient, rapid and easy way to conduct the extraction and detection of HBCD in soil.