Table 1.

Summary of eight polycyclic aromatic hydrocarbons (PAH8) and validation results of two different methods (alkali digestion and ultrasound-assisted extraction) with linearity, limit of detection (LOD), limit of quantification (LOQ), and expanded uncertainty

Compounds	Abbreviation	Quantitative ion (m/z)	Qualita-tive ion (m/z)	TEFa	Alkali digestion extraction method				Ultrasound assisted extraction method
					R2	LODb (µg/kg)	LOQc (µg/kg)	Expanded uncertaintyd (%)	R2	LOD (µg/kg)	LOQ (µg/kg)	Expanded uncertainty (%)
Benz[a]anthracene	B[a]A	228	226, 229	0.1	0.9998	0.096	0.292	4.022	0.9991	0.079	0.241	4.463
Chrysene	Chry	228	226, 229	0.01	0.9996	0.082	0.248	6.145	0.9992	0.074	0.225	6.196
Benzo[b]fluoranthene	B[b]F	252	250, 253	0.1	0.9997	0.091	0.277	5.649	0.9999	0.083	0.252	5.603
Benzo[k]fluoranthene	B[k]F	252	250, 253	0.1	0.9999	0.120	0.365	6.485	0.9995	0.105	0.317	7.061
Benzo[a]pyrene	B[a]P	252	250, 253	1	0.9994	0.070	0.212	4.511	0.9998	0.115	0.348	4.495
Indeno[1,2,3-cd]pyrene	I[c,d]P	276	274, 277	0.1	0.9999	0.129	0.391	4.784	0.9997	0.108	0.327	4.995
Dibenz[a,h]anthracene	D[a,h]A	278	276, 279	5	0.9999	0.175	0.531	4.447	0.9998	0.097	0.294	4.615
Benzo[g,h,i]perylene	B[g,h,i]P	276	274, 277	0.01	0.9983	0.105	0.318	8.608	0.9984	0.104	0.315	8.529

^aToxic equivalency factors (TEFs)

^bMethod limit of detection, 3.3σ/s (σ = standard deviation of response; s = slope of regression equation)

^cMethod limit of quantification, 10σ/s

^dExpanded uncertainties in percentage at 10 μg/kg (confidence level about 95%, k = 2). If nominal concentration level is < 100 μg/kg, the typical expanded uncertainty range should be within 44% (Codex, 2011)