Table 4.

Application of developed method for the preconcentrations of Co(II) and Hg(II).

Samples	Co mg kg−1	Hg mg kg−1
NCSZC 73014, certified	220 ± 20a	3.8 ± 0.8a
NCSZC 73014, determined	215 ± 26a	3.8 ± 0.6a
DORM2, certified	182 ± 31a	4.64 ± 0.26
DORM2, determined	179 ± 40a	4.58 ± 0.29
NCS DC78301, certified	16.5	0.22
NCS DC78301, determined	16.3 ± 1.1	±
Tap water	<LOD	<LOD
Tap waterb	0.010 ± 0.001	0.009 ± 0.001
Tigris River water	<LOD	<LOD
Mineral water	<LOD	<LOD
Tuna fish	0.20 ± 0.02	0.026 ± 0.003
Tomato	0.66 ± 0.03	<LOD
Potato	0.65 ± 0.03	0.016 ± 0.001
Macaroni	0.044 ± 0.003	<LOD
Cabbage	0.66 ± 0.01	<LOD
Red lentil	0.14 ± 0.01	<LOD
Green tea	0.17 ± 0.01	<LOD
Black tea	1.6 ± 0.2	<LOD
Mint	0.051 ± 0.004	<LOD
Mintb	0.060 ± 0.003	0.009 ± 0.001
Baby biscuit	0.044 ± 0.002	<LOD
Baby biscuitb	0.053 ± 0.003	0.010 ± 0.001
Baby rice powder	0.069 ± 0.005	<LOD
Coffee	0.058 ± 0.004	<LOD
Gluten free biscuit	0.060 ± 0.005	<LOD
Bovine liver	0.86 ± 0.04	<LOD
Meat	0.083 ± 0.006	<LOD
Beef	0.069 ± 0.004	<LOD
Soil	16.9 ± 1.4	0.65 ± 0.03

^ang g⁻¹.

^bSpiked with known amounts of Co(II) and Hg(II) to give final concentrations as 0.010 mg kg⁻.