*3.5. Water Sample Analysis*

The BPA concentration of the water samples was determined by high-pressure liquid chromatography (HPLC) equipped with a Waters 996 photodiode array (PDA) detector (Waters Corp., Milford, MA, USA) at a wavelength of 226 nm. A mixture of 0.1% trifluoracetic acid (TFA) in methanol and 0.1% TFA in water at a flow rate of 0.4 cm3/min was used as the eluent mixture to separate compounds on a SunFireTM C18 5-m 2.1 × 100 mm column (Waters Corp., Milford, MA, USA) operated at 30 ◦C. The total organic carbon (TOC) concentration of water samples was determined from the initial and final samples on a Skalar FormacsHT Total Organic Carbon/total nitrogen analyzer (Breda, The Netherlands). Possible leaching of Al, Ca, Mg, Na, and Si was analyzed from the final samples after oxidation by ICP-OES analysis (Thermo Electron iCAP 6500 Duo, Thermo Fisher Scientific, Waltham, MA, USA).
