Determination of Residues of 7 Metal Elements in Poultry Farming Wastewater by Inductively Coupled Plasma Mass Spectrometry with Iminodiacetic Acid Chelating Resin Column

A method for the determination of residues of 7 metal elements, including lead, manganese, barium, cadmium, aluminum, chromium and cobalt in poultry farming wastewater by inductively coupled plasma mass spectrometry with iminodiacetic acid chelating resin column was proposed. The poultry farming wastewater sample (25 mL) after pretreatment was taken, and passed through the activated iminodiacetic acid chelate resin column at flow rate of 2.0 mL·min⁻¹. The column was washed with 15 mL of water, and eluted with 15 mL of 5% (volume fraction, the same below) nitric acid solution. The eluate was collected, and its volume was made up to 25 mL with 5% nitric acid solution. 7 metal elements in the obtained sample solution were determined according to the working conditions of the inductively coupled plasma mass spectrometer, and internal standard method was used for quantification. It was shown that the linear ranges of the standard curves for 7 metal elements were 0.005—8.0 μg·L⁻¹, with detection limits (3S/N) in the range of 0.006—0.018 ng·L⁻¹. RSDs (n=6) of the determined values of 7 metal elements in the spiked sample were in the range of 1.7%—3.8%, and the recovery was in the range of 82.5%—93.0%.