Determination of Heavy Metals in PM_2.5 by Inductively Coupled Plasma Mass Spectrometry

Objectives To develop a method for simultaneous determination of Cr, Ni, As, Se, Cd, Tl and Pb in PM_2.5 by inductively coupled plasma mass spectrometry (ICP-MS).

Methods The PM_2.5 samples were processed in an ultrasonic bath, then the concentration of seven heavy metals in the leach solution were determined by ICP-MS.

Results The correlation coefficient of standard curves was not less than 0.999.The detection limits for Cr, Ni, As, Se, Cd, Tl and Pb were 1.21, 0.36, 0.29, 0.42, 0.30, 0.35 and 0.08 μg/L respectively.The detectabilities for Cr, Ni, As, Se, Cd, Tl and Pb were 0.0067, 0.0020, 0.0016, 0.0023, 0.0017, 0.0020 and 0.0004μg/m³ respectively. The recovery rates of seven elements except Se were in the range of 82.5%~99.8%. The relative standard deviations were less than 5%.

Conclusions The operation of pre-processing samples was easy in this method. The established method is accurate, low detection limits and reproducible with higher precision, it can be used for the analysis of metals composed in PM_2.5.