Table 1.

Determination of certified reference materials.

	GBW10050 shrimp		GBW08573 yellow croker
	Certified (mg/kg)	Measured (mg/kg)	Certified (mg/kg)	Measured (mg/kg)
As	2.5	2.4 ± 0.4	5.08 ± 0.39	4.82 ± 0.66
Cd	0.039 ± 0.002	0.035 ± 0.005	0.015	0.011 ± 0.007
Hg	0.049 ± 0.008	0.051 ± 0.004	0.169 ± 0.018	0.155 ± 0.017
Pb	0.2 ± 0.05	0.17 ± 0.07	0.25	0.22 ± 0.09
Cr	0.35 ± 0.11	0.32 ± 0.15	0.43	0.41 ± 0.05