Polychlorinated naphthalenes in groundwater samples from the Llobregat aquifer (Spain)

Polychlorinated naphthalenes (PCNs) have characteristics fairly similar to those of polychlorinated biphenyls and terphenyls (PCBs and PCTs) and although they have been used in numerous applications, very few reports on the occurrence of PCNs in water have been published. Both automated solid-phase extraction (SPE) and liquid-liquid extraction (LLE) procedures were evaluated to concentrate PCNs. High-resolution gas chromatography with electron-capture detection (HRGC-ECD) and mass spectrometric detection in the selected ion monitoring mode (SIM) were used to analyze PCNs in groundwater samples from the aquifer of the Llobregat river near Barcelona (NE Spain). The homologue distribution profiles of PCNs found in groundwater samples and the standard mixtures of Halowax (1099, 1013 and 1014) were compared. Quantification was achieved by HRGC-ECD. Total PCN concentrations expressed as Halowax 1099 equivalents ranged from < 0.5 ng/l to 79.1 micrograms/l in the water samples, with tetrachloronaphthalenes (TetraPCN) as the major group of congeners.