Environmental and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, PR China; Key Laboratory of Low-carbon Green Agriculture in Tropical region of China, Ministry of Agriculture and Rural Affairs, Haikou 571101, PR China.
Environmental and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, PR China; National Long-term Experimental Station for Agriculture Green Development, Danzhou 571737, PR China; National Agricultural Experimental Station for Agricultural Environment, Danzhou 571737, PR China; Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Haikou 571101, PR China.
J Hazard Mater. 2023 Sep 5;457:131732. doi: 10.1016/j.jhazmat.2023.131732. Epub 2023 May 29.
Threats to food safety caused by the continuous accumulation of plastic particles in the terrestrial environment is currently a worldwide concern. To date, descriptions of how plastic particles pass the external biological barrier of crop root have been vague. Here, we demonstrated that submicrometre polystyrene particles passed unimpededly the external biological barrier of maize through the split of holes in the protective layer. We identified plastic particles induced the apical epidermal cells of root tips become round, thereby expanding the intercellular space. It further pulled apart the protective layer between the epidermal cells, and eventually formed the entry pathway for plastic particles. The enhancement of oxidative stress level induced by plastic particles was the main reason for the deformation of the apical epidermal cells (increased roundness values: 15.5%), comparing to the control. Our findings further indicated that the presence of cadmium was conducive to the "holes" formation. Our results highlighted the critical insights into the fracture mechanisms of plastic particles for the external biological barriers of crop roots, providing a strong incentive to access the risk of plastic particles in agriculture security.
塑料颗粒在陆地环境中不断积累对食品安全造成的威胁是目前全世界共同关注的问题。迄今为止，关于塑料颗粒如何穿透作物根部外部生物屏障的描述还比较模糊。在这里，我们证明了亚微米聚苯乙烯颗粒可以通过保护层上的孔分裂无障碍地穿透玉米的外部生物屏障。我们发现塑料颗粒诱导根尖表皮细胞变圆，从而扩大了细胞间隙。这进一步拉开了表皮细胞之间的保护层，最终形成了塑料颗粒进入的途径。与对照相比，塑料颗粒诱导的氧化应激水平增强是导致根尖表皮细胞变形的主要原因（增加的圆度值：15.5%）。我们的研究结果进一步表明，镉的存在有利于“孔”的形成。我们的研究结果强调了对塑料颗粒穿透作物根部外部生物屏障的断裂机制的深入了解，为评估农业安全中塑料颗粒的风险提供了有力的依据。
