COMPARISON OF THE NEW VERSION OF THIN-LAYER HEADSPACE ANALYSIS WITH AUTOGENOUS GENERATION OF THE LIQUID SORBENT (TLHS-DAI-GC-ECD) WITH LIQUID-LIQUID-EXTRACTION FOR THE DETERMINATION OF VOLATILE ORGANOHALOGEN COMPOUNDS IN LIQUID SAMPLES

Two methods of isolation and pre-concentration of volatile organohalog en compounds from liquid samples prior to their gas chromatographic an alysis - thin layer headspace analysis with autogenous generation of t he liquid sorbent and liquid-liquid extraction - were compared using m odel solutions of four such compounds. Statistical analysis of the res ults obtained was performed using (i) Dixon's Q test for the detection of outliers; (ii) Snedecor's F-test for the comparison of the precisi on of the determinations; (iii) Aspin-Welch's test for the comparison of the accuracies of the two methods; (iv) Student's t-test for the co mparison of the mean values with the true value. It was found that the precisions and accuracies of the results obtained by the two methods did not differ significantly, while liquid-liquid extraction was much more labour- and time-consuming.