Method for measuring residual phosphine in tobacco and tobacco products based on pulse flame photometric detector

The invention relates to a method for measuring residual phosphine in tobacco and tobacco products based on a pulse flame photometric detector. A target substance detected by the method is trace binding state phosphine in tobacco and tobacco products. The method comprises the following steps: (1) sample pretreatment; (2) preparation of standard phosphine gas; (3) measurement of the content of the phosphine standard gas; (4) forming of a standard work curve, namely putting about 0.5g of un-fumed tobacco and tobacco products into a 20mL of headspace bottle, transferring the standard gas from phosphine standard reserve gas to be injected into the headspace bottle, and performing GC/PFPD (gas chromatography-pulsed flame photometric detector) analysis, wherein blank and five concentration levels are included. The method has the advantages of good stability, sensitivity, limit of detection and selectivity compared with an NPD (Nitrogen Phosphorus Detector), an FPD (Flame Photometric Detector), an MS (Mass Spectrum) detector.