Prioritization of highly exposable pharmaceuticals via a suspect/non-target screening approach: A case study for...

Pharmaceuticals and personal care products (PPCPs) in the Yeongsan River, Korea were prioritized via suspect and non-target analysis using LC-HRMS (QExactive plus Orbitrap) followed by semi-quantitative analysis to confirm the priority of PPCPs. A scoring and ranking system for prioritization was suggested based on occurrence frequency and chromatographic peak area or concentration. Through suspect and non-target screening, more than 50 PPCPs were tentatively identified and ranked by the scoring system. Among them, 28 substances were finally confirmed using reference standards. For estimating concentration, 26 confirmed PPCPs and 12 additional substances not included in the first ranking were semi-quantitatively analyzed. We found that carbamazepine, metformin, paraxanthine, naproxen, and fluconazole occurred 100% of the time above the limit of quantification in 14 samples, whereas carbamazepine, metformin, paraxanthine, caffeine, and cimetidine showed maximum concentrations above 1000 ng/L. Thus, in the final prioritization list, carbamazepine, metformin, and paraxanthine shared first place, followed by caffeine, cimetidine, lidocaine, naproxen, cetirizine, climbazole, fexofenadine, tramadol, and fluconazole, with scores of 100 or above. We suggest that these 12 PPCPs are the most highly exposable substances, and thus must be considered in future water monitoring in the Yeongsan River.