Department of Agroenvironmental Chemistry and Plant Nutrition, Czech University of Life Sciences, Prague 6, Czech Republic.
J Sci Food Agric. 2013 Apr;93(6):1378-84. doi: 10.1002/jsfa.5903. Epub 2012 Oct 9.
Urban particulate matter (PM) can affect green plants either via deposition on the above-ground biomass, where the contaminants can penetrate the leaf surface, or indirectly via soil-root interaction. This experiment assessed the potential risk of PM-derived risk elements contained in vegetables. The bioavailable portions of arsenic (As), cadmium (Cd), iron (Fe), and zinc (Zn) in leafy vegetables amended by PM via soil and/or foliar application were investigated in a model pot experiment, in which lettuce and chard were cultivated.
By using the physiologically based extraction test simulating in vitro human digestive processes in the stomach and small intestine, the bioavailable portions of toxic elements from PM-amended plant biomass were extracted. Extractable portions of elements by a simulated gastric solution from biomass decreased for lettuce in the order Zn > Cd > As > Fe; while for chard, the order was As > Zn > Cd > Fe. No significant effects of PM physical fractions or soil were observed.
Although the bioavailable element portions in the PM samples were lower compared to plants, the bioavailable element contents in foliar PM-amended plant leaves exceeded the control and soil PM amendment levels, even after biomass washing.
城市颗粒物（PM）可以通过沉积在地上生物量上来影响绿色植物，污染物可以穿透叶片表面，或者通过土壤-根系相互作用间接地影响。本实验评估了蔬菜中源自 PM 的风险元素的潜在风险。通过土壤和/或叶面施用 PM 对生菜和菠菜进行了模型盆栽实验，研究了叶菜中砷（As）、镉（Cd）、铁（Fe）和锌（Zn）等元素的生物可利用部分。
通过使用模拟人体胃和小肠内消化过程的基于生理学的提取试验，从 PM 处理的植物生物量中提取了有毒元素的生物可利用部分。模拟胃液从生物量中提取的元素部分，生菜的顺序为 Zn > Cd > As > Fe；而菠菜的顺序为 As > Zn > Cd > Fe。PM 的物理部分或土壤没有显著影响。
尽管 PM 样品中的生物可利用元素部分与植物相比较低，但叶面 PM 处理的植物叶片中的生物可利用元素含量即使在生物质洗涤后也超过了对照和土壤 PM 处理水平。
