Pearson's correlation coefficients (r) were calculated to detect pair- wise relationships among the metals and TOC concentration in the in- vestigated water samples. Correlation coefficients were considered as statistically significant at the level of significance p b 0.05. To identify patterns in all physicochemical data Principal Component Analysis (PCA) was performed. Both PCA and Pearson's correlation coefficients were computed with the software package STATISTICA 6.1 (StatSoft Inc., Tulsa, OK, USA).