Possibilities of High Resolution Inductively Coupled Plasma Optical Emission Spectrometry in the Determination of Trace Elements in Environmental Materials

Table 7

Detection limits in pure solvent 𝐶_𝐿 (column 2) obtained by ULTIMA 2 by using the most prominent lines of Cr, Sb, Zn, Pb, Cd, Mn, Cu, U, and Ba (column 1) under optimal experimental conditions (Table 1), threshold concentrations in accordance with Bulgarian Regulation No. 9 on the quality of water intended for human consumption [32] (column 3), mean values [𝑋] for (𝑛=4 replicates), and the confidence interval of the mean value [Δ𝑋] for statistical confidence 𝑃=95% and 𝑓=𝑛−1=3 (column 4) as well as the RSD (column 5) of the analytical results obtained by ICP-OES in the determination of Cr, Sb, Zn, Pb, Cd, Mn, Cu, U, and Ba in NWRI TMDA-51.2 (column 4). Column 6 shows the certified values.

Most prominent lines, wavelength, λ, nm	𝐶𝐿 (ng mL ^−1)	Threshold concentrations, (ng mL^−1) in accordance with regulation no. 9 [32]	ICP-OES ULTIMA 2		Certified values, (ng mL^−1)
			Concentrations, (ng mL^−1)	RSD, %
Cr II 205.552	3.0	50	61.9 ± 1.0	1.6	62.5
Sb I 206.838	10	5.0	the element is not detected	—	3.1
Zn I 213.856	1.4	4000	105.5 ± 1.5	1.4	106
Pb II 220.353	5.0	10	73.0 ± 1.0	1.3	72.9
Cd II 226.502	1.4	5.0	25.0 ± 0.5	2.0	25.1
Mn II 257.610	0.13	50	81.8 ± 1.2	1.4	82.0
Cu I 324.754	1.3	2000	90.8 ± 1.2	1.3	91.0
U II 385.958	1.4	30	30.0 ± 1.1	3.3	29.3
Ba II 455.403	0.12	no data	73.0 ± 1.0	1.3	73.3