Abstract:A method for determining mercury content in the food paper-plastic composite packaging materials with wet digestion-atomic fluorescence spectrometry was developed. The sample of 0.500 0 g with 10 mL of concentrated nitric acid and 2 mL of hydrogen peroxide digestion 4 h could get the best results. The best optimized atomic fluorescence spectrometer detection conditions of mercury were as followed: a negative high voltage of 210 V, the shielding gas flow rate of 900 mL/min, the carrier gas flow rate of 500 mL/min, injection volume of 0.5 mL, the Hg lamp current of 10 mA, the atomizer height of 10 mm, reading time of 10s, the delay time of 1.0 s, carrier medium for the 5% hydrochloric acid, potassium borohydride solution and the concentration of the potassium hydroxide solution 5 g/L. Mercury showed a good linear relationship in the range of 0.0 to 20.0 ng/mL with a correlation coefficient of 0.999 6, and the detection limit was 0.002 5 μg/mL. The recoveries of mercury range from 95.93% to 97.38%, and the relative standard deviations of mercury ranged from 3.02% to 3.85%. The method has the advantages of high precision, low detection limit and high accuracy, and it is applicable to detection and analysis of mercury content in food paper-plastic composite packaging materials in the market.