Static headspace versus head space solid-phase microextraction (HS-SPME) for the determination of volatile organochlorine compounds in landfill leachates by gas chromatography

The determination of five volatile organochlorine compounds, VOX (chloroform, 1,1,1-trichloroethane, carbon tetrachloride, trichloroethene and tetrachloroethene) in raw landfill leachates and biologically cleansed leachates by GC-MS is investigated. Two extraction and preconcentration procedures were evaluated for recovery of such analies from the samples, including static headspace (HS) and solid phase microextraction by sampling the headspace above the sample (HS-SPME). Optimisation of operating parameters for the best performance of both, sampling and preconcentration techniques was described. Detection limits, time of analysis, precision and linear ranges of both introduction techniques have been established. Application of proposed methods to the determination of the five VOX under study in the above referred samples revealed the absence of such analytes in both leachates. Then both methods were applied to the determination to the five organochlorine compounds under study on spiked leachates samples. While HS-GC-MS offered better analytical precision than HS-SPME-GC-MS, this last technique gave a faster analytical response because no dilution must be done for a reliable VOX determination in landfill leachates. In any case, both sample introduction techniques tested provides excellent recoveries and good analytical precision (ranged from 1 to 3%).