Table 7
Average concentration of the migrated hazardous metals according to different migrant solutions at 100°C for 30 min (mg/L)

Materials	solution	Pb	As	Cd	Ni	Al
Stainless steel	Distilled water	ND1)	0.001 (0.001)2)	ND	0.000 (0.001)	ND
			ND-0.0023)		ND-0.001
	Citric acid	0.001 (0.001)	0.001 (0.002)	ND	0.007 (0.003)	0.021 (0.009)
	solution (0.5%)	ND-0.002	ND-0.003		0.005-0.010	0.012-0.029
	NaCl solution (1%)	ND	0.006 (0.001)	ND	ND	0.001 (0.002)
			0.005-0.007			ND-0.003
Hard aluminium	Distilled water	ND	0.001 (0.002)	ND	0.001 (0.001)	0.007 (0.001)*4)
			ND-0.003		ND-0.001	0.006-0.008
	Citric acid	0.000 (0.001)	ND	ND	0.005 (0.002)**	51.97 (4.402)
	solution (0.5%)	ND-0.001			0.003-0.006	47.50-56.30
	NaCl solution (1%)	ND	0.008 (0.002)	ND	ND	0.002 (0.002)
			0.007-0.010			ND-0.003
Soft aluminium	Distilled water	ND	ND	ND	0.001 (0.000)	0.001 (0.002)
					0.001	ND-0.004
	Citric acid	ND	ND	ND	0.002 (0.000)***	24.89 (3.130)****
	solution (0.5%)				0.002	21.45-27.57
	NaCl solution (1%)	ND	0.006 (0.002)	ND	0.000 (0.001)	0.002 (0.002)
			0.004-0.008		ND-0.001	ND-0.003
Fluoro- carbon resin	Distilled water	ND	0.001 (0.002)	ND	0.001 (0.001)	ND
			ND-0.003		ND-0.001
	Citric acid	0.001 (0.001)	0.001 (0.001)	ND	ND	0.040 (0.003)*****
	solution (0.5%)	ND-0.002	ND-0.002			0.037-0.043
	NaCl solution (1%)	ND	0.001 (0.002)	ND	0.000 (0.001)	0.001 (0.001)
			ND-0.004		ND-0.001	ND-0.002

Not detected.
Average (Standard Deviation).
Minimum concentration-Maximum concentration.
^{*,**,***,****,*****}p-value shows significant differences of hazardous metal concentration between non-scratch and scratch on the bottom of a pot (p<0.05).