超高效液相色谱-静电场轨道阱高分辨质谱法测定土壤中氯化石蜡OA

In this study,a method was established for the simultaneous determination of short-,medium-,and long-chain chlorinated paraffins(SCCPs,MCCPs,and LCCPs)in soil using ultra-high performance liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry(UPLC-Orbitrap HRMS)for highly sensitive detection.The method is based on a pretreatment proce-dure involving ultrasonic extraction and multi-layer silica gel column cleanup,coupled with optimiza-tion of the extraction solvent type,volume,and extraction frequency.Soil samples were subjected to ultrasonic extraction with a dichloromethane/n-hexane mixture,followed by multi-layer silica gel col-umn cleanup,elution with dichloromethane/n-hexane,and constant-volume adjustment prior to UPLC-Orbitrap HRMS analysis.The chromatographic separation was performed on a Hypersil GOLD VANQUISH C18 column,and mass spectrometric detection was conducted via a heated electrospray ionization(H-ESI)source in the negative ion mode under full-scan acquisition.SCCPs and MCCPs exhibited good linearity over the range between 10-5 000 ng·mL-1,and LCCPs exhibited good linear-ity over the range between 10-1 000 ng·mL-1,with correlation coefficients(r2)greater than 0.98.The method detection limits(MDLs)for SCCPs,MCCPs,and LCCPs were 18.9,19.7,and 2.06 ng·g-1,respectively.The average recoveries of CPs at low,medium,and high spiked concentration levels ranged between 75.6%-116%,80.5%-99.3%,and 93.1%-109%,with relative standard deviations(RSDs)of 2.2%-9.3%,3.6%-6.5%,and 1.8%-4.6%,respectively.The developed method was applied to analyze CPs in 11 soil samples collected from a typical rubber industrial park.The detec-tion frequencies of SCCPs,MCCPs,and LCCPs were all 100%,with concentration ranges between 48.5-2 490 ng·g-1(mean 682 ng·g-1),82.3-4 090 ng·g-1(mean 1 560 ng·g-1),and 10.7-809 ng·g-1(mean 242 ng·g-1),respectively.MCCPs were identified as the predominant congener group,ac-counting for 62.7%of the total CPs.This method exhibits good reproducibility and high sensitivity,enabling efficient extraction and accurate quantification of CPs in soil,and can serve as a viable analytical option for environmental monitoring and risk assessment.