HPLC-MS method for tracing multiclass PPCPs in soil and water: optimization of ionization and extraction strategies

A high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed for the determination of 27 multiclass pharmaceuticals and personal care products (PPCPs) in soils and 30 PPCPs in surface water and groundwater using atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI). Conventional PPCP methods often suffer from limited analyte coverage and pronounced matrix effects, particularly in soils, challenges that are further exacerbated in conventional single-quadrupole HPLC-MS systems compared to MS/MS platforms that are not readily accessible in many developing regions. To address these challenges, the method targeted diverse compound classes, including antibiotics, analgesics, non-steroidal anti-inflammatory drugs, β-blockers, lipid regulators, estrogens, and other emerging contaminants, supported by systematic optimization of extraction and ionization conditions. A single extraction protocol enabled simultaneous analysis of 27 PPCPs in soils with APCI providing broader analyte coverage and reduced matrix effects compared to ESI. Median quantification limits were 1.5 ng g^-1 for soils, 17.2 ng L^-1 for surface water, and 5.8 ng L^-1 for groundwater. Application to samples from the Yamuna River Basin (Delhi, India) revealed at least 15 PPCPs across all matrices. The study demonstrates that optimized single-quadrupole HPLC-MS provides a sensitive and accessible approach for routine multiclass PPCP monitoring.