Lead absorption capacity in different parts of plants and its influencing factors: a systematic review and meta-analysis

Abstract

Abstract People pose a serious risk by eating plants contaminated with lead in their soil. Lead enrichment in different parts of plant roots, stems, and leaves is controversial. Accordingly, a meta-analysis was conducted to investigate the ability of different plants to enrich lead and the main factors for lead absorption. The results of this study indicated that all parts of plants accumulated significantly lead. The concentrations of lead in different parts of root, stem and leaf were analyzed, and it was found that these concentrations followed an order of root > stem > leaf. Alkaline soil was beneficial to lead absorption by plants in this study. Significant differences were found in lead enrichment ability among vegetables, gramineae and trees. When the lead concentration in soil was higher than 20mg/kg, the lead absorption in different parts of roots, stems, and leaves was more. Lead is most absorbed in trees (e.g., ulmus pumila and murraya paniculate). It is the least in gramineae (e.g., rice, maize plants, and sweet sorghum). It is argued that this study is beneficial to select vegetables suitable for absorption of heavy metals from polluted soil. This study can help to clarify the ability of a variety of plant parts to enrich lead and the factors for lead enrichment in plants, so as to propose more reasonable lead pollution control strategies and guide people to make healthy choices when choosing edible plants.