The efficiency of methods for the determination of hexachlorobenzene (HCB) and pentachlorophenol (PCP) in soil
samples was evaluated. An on-line method was applied for HCB determination. Soil samples were transferred to
chromatographic columns prepacked with alumina. The HCB elution was processed with n-hexane. The PCP was
extracted from soil samples with n-hexane–acetone in an ultrasonic bath. After re-extraction with K2CO3 solution
PCP was acetylated with acetic anhydride. The pentachlorophenyl acetate derivative was then extracted with
n-hexane. The HCB and PCP derivative were analyzed by gas chromatography with electron capture detection
(GC-ECD). Mean recoveries obtained from soil samples fortified at levels of 0.5; 4 and 20 ng g1, ranged from 91
to 100% for HCB, and for PCP, at levels of 10; 40 and 200 ng g1, ranged from 88 to 101%. These results
demonstrated the efficiency of the proposed methods. © 1998 Elsevier Science B.V. All rights reserved.