[Determination of four classes of 34 chlorinated persistent organic pollutants in seawater by solid-phase extraction and gas chromatography-electrostatic field orbitrap high resolution mass spectrometry].

• DOI: 10.3724/sp.j.1123.2024.07017
• Publication Date: 2025-04-08
• Authors: M. Gao; Xiaoying Li; Yuan Gao; Haijun Zhang; Jiping Chen
• Keywords: Orbitrap; Solid phase extraction

Ocean acts as a "sink" for pollutants in the natural environment. Consequently, issues focused on marine pollution from terrestrial origin is attracting increasing attention. Persistent organic (POPs), including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), short-chain chlorinated paraffins (SCCPs), and dechlorane plus isomers (DPs), are serious hazards both environment humans. These POPs have been widely detected typically present at trace levels; however, separating determining individual contaminants require large amounts of sampling time. Establishing an accurate analytical method typical critical studying their environmental behavior associated ecological risks to In this study, we developed based solid-phase extraction (SPE) combined with gas chromatography-electrostatic field orbitrap high resolution mass spectrometry (GC-Orbitrap-HRMS) 34 seawater, 25 OCPs, six PCB congeners, SCCPs two DPs. The chromatographic conditions MS parameters were optimized, effects solvent purification systematically studied. Dichloromethane exhibited satisfactory efficiencies during liquid-liquid (LLE) seawater samples, recoveries 73.1%-120.5% 87.2%-101.7% PCBs, 105.5% SCCPs, 74.9%-78.6% DPs, respectively. Purification using SPE column 500 mg Florisil was adopted, 9∶1 (v/v) n-hexane/acetone confirmed eluent between 68.2% 122.8% all POPs. A DB-5MS (15 m×0.25 mm×0.10 μm) capillary used separate target compounds, electron ionization (EI) source detect OCPs whereas DPs determined negative chemical (NCI) source. All compounds analyzed full-scan mode. An internal standard quantification while isotope dilution PCBs severe interference observed detection mixture co-extracted substances completely eliminated following purification. good linearities corresponding ranges, correlation coefficients (R2) exceeding 0.9. demonstrated low limits under optimized conditions, values 0.009-0.061 ng/L 0.006-0.016 2.78 0.021-0.023 lower determination 0.06-0.24, 0.02-0.06, 11.12, 0.08-0.09 ng/L, Accuracy precision validated by samples spiked low, medium, levels, which ranged 70.6% 128.9%. Relative deviations (n=6) be 0.2%-19.2%. results highlight suitability analyzing seawater. characterized simple sample pretreatment, sensitivity, fast throughput, cost-effectiveness, stability trace-level detection; hence, it suitable rapid analysis This expected play significant role monitoring emergency surveillance pollution. applied collected Bohai, revealed that highest frequency (90%) recorded α-hexachlorocyclohexane (α-HCH) only 30% samples. other below limit. PCB-52 congener much higher concentrations than POPs, value 130.6 recorded. particular attention must paid SCCPs.