Table 1 Description of optimum analytical conditions and analysis of selected metals in SRM
| Â | Cd | Cr | Cu | Fe | Mn | Pb | Zn |
|---|---|---|---|---|---|---|---|
Wavelength (nm) | 228.8 | 357.9 | 324.8 | 248.3 | 279.5 | 217.0 | 213.9 |
HC lamp current (mA) | 4.0 | 5.0 | 3.0 | 8.0 | 5.0 | 7.0 | 4.0 |
Slit width (nm) | 0.3 | 0.5 | 0.5 | 0.2 | 0.4 | 0.3 | 0.5 |
Fuel gas flow rate (L/min) | 1.8 | 2.6 | 1.8 | 2 | 1.9 | 1.8 | 2 |
Detection limit (μg/L) | 4.0 | 6.0 | 4.0 | 6.0 | 3.0 | 10.0 | 2.0 |
SRM-certified level (mg/kg) | 0.38 | 130 | 34.6 | 35,000 | 538 | 18.9 | 106 |
SRM-measured level ± SD (mg/kg) | 0.36 ± 0.03 | 138 ± 8 | 35.2 ± 1.2 | 34,300 ± 385 | 547 ± 11 | 19.3 ± 1.4 | 109 ± 3.2 |