Analysis of Gas Phase Nonylphenol with Solid-phase Microextration under Non-equilibrium System

Nonylphenol (NP) is a degradation product of nonylphenol ethoxylates (NPE), which are widely used as the non-ionic surfactants. Exposure to NP is suspected to cause adverse effects on growth and reproductive system. Due to the possible human exposures, the estrogenic activity of NP has raised concerns. he USEPA has mentioned that NP in household cleaning products could be an important source of indoor air pollution. For the assessments of gas-phase NP exposures, sampling with PUF and XAD2 resin are mostly performed. However, solvent desorptions are commonly needed for the techniques which make the methods not very convenient. On the other hand, solid phase microextraciton (SPME) presents many advantages over conventional analytical methods by combining sampling, preconcentration, and direct transfer of the analytes into a standard gas chromatograph (GC) system. Therefore, the purpose of this research was to develop a sampling method for gaseous NP based on the technique of SPME. he validation system in this study was composed by the air generator, syringe pump, mixing chamber and exposure chamber. Known concentrations of gaseous NPs were generated by the injection of NPs solution followed by evaporation under stable air flow. Then, the SPME fiber was exposed to the well-mixed vapor in the exposure chamber, and the analysis with GC/MS was performed afterwards. Under the air velocity equal to 18.57cm/s, linear relationship was observed between the mass collected on the fiber and the exposure time (y=(2.29×10-4±1.05×10-5)x-(3.66×10-3±4.36×10-3), r= 0.997).his study demonstrated the potential of using SPME fiber for NPs determination under non-equilibrium conditions. More validations needed to be performed before further applications in the field.