Table 5.

Concentration of heavy metals in the reference material.

Parameter	Ni	Pb	Cd
Theoretical value (mg/kg)	0.5	0.5	0.3
Found value (mg/kg)	0.51	0.52	0.34
	0.54	0.54	0.33
	0.49	0.56	0.35
	0.61	0.48	0.31
	0.56	0.55	0.34
	0.47	0.51	0.31
Average	0.53	0.53	0.33
SD	0.05	0.03	0.02
RSD (%)	9.63	5.66	6.1
Recovery (%)	106	106	110
LOD (µg/kg)	0.39	1.37	0.08
LOQ (µg/kg)	1.57	5.01	0.30