Analysis of aqueous streams contaminated with complex organic mixtures commonly used in industrial processes can be problematic. In this study, we describe the development of the solid-phase microextraction (SPME) headspace extraction technique in combination with gas chromatography (GC) to measure the leakage of n-decanol and Exxsol(R) D-110 (commercial solvent containing primarily napthenes and paraffins) into aqueous streams. These streams were derived from a continuous liquid membrane separator for the removal and recovery of Cr(VI) from industrial effluents. In one stream that was dilute in Cr(VI) at pH 2-3, a method giving good results for n-decanol analysis involved the addition of n-octanol as an internal standard to GC calibration standards and test samples prior to SPME extraction with the appropriate adjustment of pH. The addition of 20 w/w% NaCl as an additional solute to all standards and test samples with pH adjustment was found to be successful for quantitative determination of Exxsol(R) D-110. In a second stream that was strongly alkaline and more concentrated in Cr(VI), GC calibration using standards containing NaOH and 300-500 ppm Cr(VI) gave satisfactory results for quantitative determination of both species.