Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus, Vehari, 61100, Pakistan.
MOE Key Laboratory of Pollution Process and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
Environ Sci Pollut Res Int. 2019 Jan;26(1):362-370. doi: 10.1007/s11356-018-3605-7. Epub 2018 Nov 5.
Soil contamination with heavy metals is a global issue confronting the environmental pollution and human/animal health. Much work has been done on physiological and antioxidant responses of wheat in hydroponic experiments and health risks from individual heavy metal contamination to human, but limited information is available on their combined application in soil. Therefore, this pot study delineates the uptake of lead and cadmium, as well as physiological responses of wheat and associated health risks under different levels of alone and combined Cd and Pb treatments. Metal uptake increased with their increasing applied levels. The highest Cd (4.24, 1.38, and 0.92 mg kg) and Pb (763.33, 39.63, and 16.35 mg kg) concentrations in root, shoot, and grain, respectively, were observed at highest applied levels (0.4 mM Cd and 10 mM Pb). Furthermore, all the treatments increased lipid peroxidation and activities of superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase, while decreased total chlorophyll contents and membrane stability index. Under combined application of Cd and Pb, the toxicity and detoxification responses of wheat increased compared to alone treatments. Multivariate analysis further confirmed the toxicity and accumulation pattern of metals under alone and combined treatments. Target hazard quotient values of Cd and Pb were < 1 under alone and combined treatments. The health hazard index values of Pb (97.07 and 87.89%) were higher than those of Cd (2.93 and 12.10%) in combined application for human and buffalo, respectively. This study highlights that the multi-metal contamination (Cd and Pb) is detrimental for wheat growth and human/animal health.
土壤重金属污染是一个全球性的环境问题，关乎着环境污染和人类/动物健康。人们已经在水培实验中对小麦的生理和抗氧化反应以及单个重金属污染对人类的健康风险进行了大量研究，但关于它们在土壤中的联合应用的信息有限。因此，本盆栽研究描述了在不同水平的单独和组合 Cd 和 Pb 处理下，小麦对铅和镉的吸收以及生理反应和相关的健康风险。金属吸收随其应用水平的增加而增加。在最高应用水平（0.4 mM Cd 和 10 mM Pb）下，根、茎和籽粒中 Cd（4.24、1.38 和 0.92 mg kg）和 Pb（763.33、39.63 和 16.35 mg kg）的浓度最高。此外，所有处理均增加了脂质过氧化和超氧化物歧化酶、过氧化氢酶、抗坏血酸过氧化物酶和过氧化物酶的活性，而总叶绿素含量和膜稳定性指数降低。在 Cd 和 Pb 的联合应用下，与单独处理相比，小麦的毒性和解毒反应增加。多元分析进一步证实了单独和联合处理下金属的毒性和积累模式。单独和联合处理下 Cd 和 Pb 的目标危害商值均<1。在人类和水牛中，Pb（97.07 和 87.89%）的健康危害指数值高于 Cd（2.93 和 12.10%）。本研究强调了多金属污染（Cd 和 Pb）对小麦生长和人类/动物健康的危害。
