Nondestructive Discrimination of Lead (Pb) in Preserved Eggs (Pidan) by Near-Infrared Spectroscopy and Chemometrics

Table 1

Detailed information of the unleaded and leaded pidan samples.

Producing areas	Batch size	Pb contents (ppm)^a	Types^b
Yangzhou, Jiangsu	39	Non-detected^c	U
Yancheng, Jiangsu	36	Non-detected	U
Yangzhou, Jiangsu	40	Non-detected	U
Jiaxing, Zhejiang	33	Non-detected	U
Shaoxing, Zhejiang	14	Non-detected	U
Wuxi, Jiangsu	36	Non-detected	U
Hangzhou, Zhejiang	32	Non-detected	U
Hangzhou, Zhejiang	36	Non-detected	U
Hangzhou, Zhejiang	33	Non-detected	U
Hangzhou, Zhejiang	32	Non-detected	U
Yancheng, Jiangsu	26	1.2~2.3	L
Jiaxing, Zhejiang	22	6.4~7.8	L
Wuxi, Jiangsu	20	2.2~3.2	L
Hangzhou, Zhejiang	29	8.9~12.8	L
Hangzhou, Zhejiang	28	4.1~5.9	L
Hangzhou, Zhejiang	22	1.2~1.7	L

aThree samples from each batch were analyzed by ICP-MS.
^bU: “unleaded” and L: “Leaded.”
^cThe limit of detection (LOD) was 0.033 ppm.