The soft polyethylene Pasteur pipette (ca. 8-mL capacity) is manufactured by Continental Lab Products (San Diego, CA, USA) and was purchased from Practical Mediscience Pte., Ltd. (Singapore).A 100-L syringe used for injection of extraction solvent and a 10-L microsyringe used for GC–MS injection were purchased from SGE (Sydney, Australia). The 10-mL plastic syringe was bought from HSW (Tuttlingen, Germany).