Abstract:
To clarify content and speciation distribution of heavy metals(such as lead, cadmium, and arsenic)in crabapple leaves from different geographical origins, crabapple leaf samples were selected from crabapple species including Yunnan Province(
Malus×micromalus Makino), Shandong Province(
Malus halliana Koehne), and Hebei Province(
Malus bhutanica(W. W. Sm.)J. B. Phipps), all sourced from regions with relatively high heavy metal pollution.Samples were pre-treated using microwave digestion.Concentrated nitric acid, concentrated hydrochloric acid, and hydrogen peroxide were used as digestion reagents.A digestion procedure was set, and samples were digested using a microwave digestion system.Contents of lead, cadmium, and arsenic were determined based on response intensity of these elements in ICP-MS standard solutions.BCR sequential extraction method was employed to extract four speciation forms of heavy metals(acid-extractable, reducible, oxidizable, and residual states), and proportion of each speciation form was calculated.Results indicated that significant differences in environmental factors across origins significantly influenced heavy metal content and speciation distribution in crabapple leaves, with these effects primarily related to soil properties and pollution levels.Specifically, contents of lead, cadmium, and arsenic in crabapple leaves from Hebei Province were significantly higher than those from the other two provinces, with specific values of 0.25, 0.08, and 0.12 mg/kg, respectively.In contrast, effective form content of three heavy metals in leaves from Yunnan and Shandong provinces both exceeded 65%, indicating a strong potential for secondary release.A scientific basis for evaluating quality and safety of crabapple leaves and environmental quality of their habitats was provided, thereby contributing to enhancement of their medicinal value.