Determination of iodine in workplace air by inductively coupled plasma mass spectrometry / 中国职业医学

ABSTRACT

Objective To establish a solvent desorption inductively coupled plasma-mass spectrometry (ICP-MS) method for determination of iodine in workplace air. Methods Iodine in workplace air was collected with alkaline activated carbon tube and desorbed with 10.0 mL pure water or 20 mmol/L sodium bicarbonate solution. Rhenium-185 was used as an internal standard for quantification. The sample was determined in standard mode and kinetic energy discrimination collision (KED) mode by ICP-MS. Results In standard mode, iodine showed a good linear range in the concentration of 9.0 to 1 100.0 μg/L, with a correlation coefficient of 0.999 3 and a detection limit of 2.7 μg/L. In KED mode, iodine showed a good linear range in the concentration of 24.3 to 800.0 μg/L, with a correlation coefficient of 0.999 1 and a detection limit of 7.3 μg/L. The average desorption efficiency using pure water ranged from 99.1% to 106.7%, with within-run relative standard deviation (RSD) of 3.1% to 8.0% and between-run RSD of 4.9% to 9.3%. The average desorption efficiency using sodium bicarbonate solution ranged from 96.5% to 105.3%, with within-run RSD of 4.9% to 8.6% and between-run RSD of 2.5% to 9.9%. There were no statistical significant differences in the main effects of desorption solution, ICP-MS detection mode, their interaction on average desorption efficiency and within-run RSD (all P>0.05). Samples could be stored at room temperature for at least 7 days. Conclusion This method is highly sensitive, accurate, and suitable for the determination of iodine in workplace air. The sample pretreatment is simple and rapid.