DEVELOPMENT OF A DEEP EUTECTIC SOLVENT-BASED MICROEXTRACTION METHOD FOR THE TRACE DETERMINATION OF EMERGING ORGANIC POLLUTANTS IN WATER FROM BABYLON GOVERNORATE, IRAQ

The emerging organic pollutants, such as pharmaceuticals, personal care products and industrial phenols, are found in rivers, groundwater and treated effluents at levels as low as ng L-1 to low µg L-1 and cannot be directly measured by an instrument. In this study, a dispersive liquid–liquid microextraction method (DLME) based on a hydrophobic deep eutectic solvent (DES) with increasing DL volume as evaporated DES was used as the sole extraction phase followed by HPLC with diode-array detection (DAD), was developed. The following five model pollutants were investigated: Bisphenol A, 4-tert-octylphenol, triclosan, diclofenac and ibuprofen. The DES was formulated by the gentle heating process, without the help of any solvent; and it was characterized by FTIR, density, viscosity, water content and stability in water. A 25 − 1 fractional design was applied for the screening of the extraction variables while the Box–Behnken design was employed for optimization. With the best conditions (90µL of DES, pH 3.0, 3 min vortex, no salt) the calibration graphs were linear in the range between LOQ and 100µgL-1 with R2 values ≥0.9978, limits of detection ranged between 0.09 and 0.31 µg L-1, enrichment factors were in the range 88–121 and extraction recoveries were in the range 63.4–87.1%. Per day and within day RSD values were not greater than 5.8% and 7.9% respectively and recoveries in spiked waters were from 86.5% to 106.8%. This method was used to test water samples in Babil Governorate, Iraq. The concentrations of Bisphenol A, triclosan and diclofenac in water samples of Shatt al-Hilla downstream of Hilla city and its treated municipal discharges were in the range of 0.41-3.27 µg L-1, while other water samples (Tap and well water) were not detected. Only less than 0.2 mL of organic reagents per sample were consumed and it received a score of 71 in Analytical Eco-Scale and 0.68 in AGREEprep, while liquid–liquid extraction scored 63 and 0.21, respectively.