DETERMINATION OF PRIORITY PHENOLIC-COMPOUNDS IN SOIL SAMPLES BY VARIOUS EXTRACTION METHODS FOLLOWED BY LIQUID-CHROMATOGRAPHY ATMOSPHERIC-PRESSURE CHEMICAL-IONIZATION MASS-SPECTROMETRY

An analytical protocol for the determination of priority phenolic comp ounds: phenol, 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol. 2,4 ,6-trichlorophenol, pentachlorophenol, 2-nitrophenol, 4-nitrophenol, 2 ,3-dinitrophenol, 4-methylphenol and 2,4-dimethylphenol, in soil sampl es, is presented. The method uses Soxhlet extraction with methanol-wat er (4:1) both containing 2% triethylamine. Recoveries varied in the ra nge from 67 to 97% with a standard deviation between 8 and 14%. Additi onal extraction methods of phenols from soil samples include the use o f the microwave-assisted extraction procedure. Results demonstrated th at most of these compounds can be recovered in good yields (>70%) from the matrix investigated, except nitrophenols that suffer degradation. Detection Limits varied within a range from 20 ng/g for 2,4-dimethylp henol to 100 ng/g for pentachlorophenol, were obtained when using LC-U V. However these values were greatly improved when using LC-APCI-MS in negative ion mode. Validation of the method by analysing a reference soil sample from the BCR program containing eight polycyclic aromatic hydrocarbons and pentachlorophenol, and the analysis of it real enviro nmental soil sample containing pentachlorophenol are also reported. (C ) 1998 Elsevier Science B.V. All rights reserved.