Arsenic (As) and lead (Pb) are highly toxic and carcinogenic metal(loid)s. The present study evaluated the human exposure risk via estimating As and Pb uptake and physiological/biochemical modifications inside spinach plant grown under metal(loid)-contaminated growth medium. Plants were treated with three levels of each metal(loid) (0, 25 and 125 µM) for four weeks. The spinach plants accumulated high concentration of metal(loid)s in roots (0–18.9 ug g⁻¹ Pb and 0.2–22.7 ug g⁻¹ As) and less were translocated towards shoot (0–0.3 ug g⁻¹ Pb and 0.2–8.8 ug g⁻¹ As). Metal(loid) accumulation in plants decreased plant biomass and pigment contents and provoked oxidative stress by increased hydrogen peroxide (H₂O₂) production in roots up to 65% and 22%, respectively, for As and Pb. The production of H₂O₂ in leaves was decreased up to 59% and 45%, respectively, for As and Pb than control. Moreover, the antioxidant system (superoxide, catalase, guaiacol peroxidase, ascorbate peroxidase) gets activated under metal(loid) stress. The exposure assessment indices revealed high carcinogenic (CR > 10^–4) and non-carcinogenic (HQ > 1) risks owing to the consumption of As- and Pb-contaminated spinach leaves. Results revealed As is being more toxic to plants and humans than Pb. These findings suggest possible alarming consequences of As and Pb to spinach and their assimilation within the edible tissues.

砷 (As) 和铅 (Pb) 是剧毒和致癌的金属 (类)。本研究通过估计在金属（类物质）污染的生长培养基下生长的菠菜植物内的 As 和 Pb 吸收和生理/生化变化来评估人类暴露风险。用三种水平的每种金属（样物质）（0、25 和 125 µM）处理植物 4 周。菠菜植物在根部积累了高浓度的金属（类物质）（0-18.9 ug g ^-1 Pb 和 0.2-22.7 ug g ^-1 As），较少向茎部转移（0-0.3 ug g ^-1 Pb 和 0.2 –8.8 ug g ^-1 As)。植物中的金属（样物质）积累会降低植物生物量和色素含量，并通过增加过氧化氢（H ₂ O ）引起氧化应激₂ ) As 和 Pb 在根中的产量分别高达 65% 和 22%。与对照相比，As 和 Pb 叶片中 H ₂ O ₂的产生分别下降了 59% 和 45%。此外，抗氧化系统（超氧化物、过氧化氢酶、愈创木酚过氧化物酶、抗坏血酸过氧化物酶）在金属（样物质）压力下被激活。暴露评估指数显示，食用受 As 和 Pb 污染的菠菜叶具有高致癌性（CR > 10 ^–4）和非致癌性（HQ > 1）风险。结果显示，As 对植物和人类的毒性比 Pb 更大。这些发现表明 As 和 Pb 对菠菜及其在可食用组织中的同化可能产生令人担忧的后果。