Determination of phthalate esters in bottled water using dispersive liquid–liquid microextraction coupled with GC-MS

Dispersive liquid-liquid microextraction method was developed for the determination of the amount of phthalate esters in bottled drinking water samples and dispersive liquid-liquid microextraction samples were analyzed by GC-MS. Various experimental conditions influencing the extraction were optimized. Under the optimized conditions, very good linearity was observed for all analytes in a range between 0.05 and 150 μg/L with coefficient of determination (R²) between 0.995 and 0.999. The LODs based on S/N = 3 were 0.005-0.22 μg/L. The reproducibility of dispersive liquid-liquid microextraction was evaluated. The RSDs were 1.3-5.2% (n = 3). The concentrations of phthalates were determined in bottled samples available in half shell. To understand the leaching profile of these phthalates from bottled water, bottles were exposed to direct sunlight during summer (temperature from 34-57°C) and sampled at different intervals. Result showed that the proposed dispersive liquid-liquid microextraction is suitable for rapid determination of phthalates in bottled water and di-n-butyl, butyl benzyl, and bis-2-ethylhexyl phthalate compounds leaching from bottles up to 36 h. Thereafter, degradation of phthalates was observed.