[Study on residues of heavy metals and harmful elements in Qingqiao and Laoqiao based on chemometrics].

ABSTRACT

Forsythiae Fructus is divided into Qingqiao and Laoqiao due to different harvesting periods. So far, the accumulation of heavy metals in the two types of Forsythiae Fructus has not been reported. In this study, the residual levels of copper(Cu), lead(Pb), chromium(Cr), arsenic(As), cadmium(Cd) and mercury(Hg) in 29 batches of Laoqiao and 60 batches of Qingqiao were determined by inductively coupled plasma mass spectrometry(ICP-MS). The samples were collected from Shanxi, Shaanxi, Henan, and Hebei Provinces. In addition, the diversity and correlation of harmful elements in Qingqiao and Laoqiao were analyzed by multivariate statistical method. Furthermore, principal component analysis(PCA) was used to analyze the harmful elements concentrations of Qingqiao and Laoqiao. The results showed that there was a significant difference on the residual levels of heavy metals and harmful elements between Qingqiao and Laoqiao. Among them, the content of Pb in Laoqiao is significantly higher than that in Qingqiao(P<0.01), while the content of Cu is significantly lower than that in Qingqiao. However, the difference in harmful elements among different producing areas of Forsythiae Fructus is not significant. PCA analysis showed that Qingqiao and Laoqiao were successfully grouped into two categories. This study suggests significant difference in the residual levels of heavy metals and harmful elements between Qingqiao and Laoqiao. Besides, Forsythiae Fructus has a certain enrichment of Pb in the fruit ripening stage(Laoqiao). This study provides a reference for the quality classification and safety of Forsythiae Fructus.