因为他们提供的许多优点(力量,低成本,耐用性,轻量级,阻力,等。),塑料是我们日常生活中不可或缺的一部分,产量不断上升。然而,他们的废物管理仍然不足,导致它们在环境中的释放和积累,代表了主要的污染源。它们的降解会导致尺寸可变的碎片,包括微塑料(0.1μm-5mm)甚至纳米塑料(<0.1μm),其对生态系统和人类健康的潜在影响引起了人们的关注。它们可能引起的潜在不良反应已使用体外和体内模型进行了评估。然而,由于微米和纳米塑料的一些特殊特性,关于常规体外试验是否适合评估其毒性,存在着挑战性的问题。例如,低密度塑料漂浮在培养基表面,不能与粘附在培养板底部的细胞接触,这阻碍了对潜在不利影响的正确评估,并导致对毒理学测定的误解。在这次审查中,我们讨论了使用常规体外试验评估微米和纳米塑料毒性的主要问题。文献调查允许提出一些解决方案来规避这些问题,包括使用数学模型来准确确定递送到细胞的颗粒剂量。先进的3D模型(类器官),倒置细胞培养模型,细胞培养在空气-液体界面或动态条件下。最后,我们为进一步研究微米和纳米塑料毒性的体外评估提出了一些观点和建议,强调使用标准化方案进行比较的重要性,并且样品和实验条件更能代表现实生活中的暴露。
Because of the many advantages they offer (strength, low cost, durability, lightweight, resistance, etc.), plastics are integral part of our daily life with a production constantly rising. However, their waste management is still inadequate, resulting in their release and accumulation in the environment, representing a main source of pollution. Their degradation results in debris of variable size including microplastics (0.1 μm-5 mm) and even nanoplastics (<0.1 μm), whose potential impact on ecosystems and human health have raised concerns. The potential adverse effects they may cause have been evaluated using both in vitro and in vivo models. However, due to some specific characteristics of micro- and nanoplastics, there are challenging questions about whether conventional in vitro tests are appropriate for evaluating their toxicity. For example, low-density plastics float on the surface of the culture medium and cannot come into contact with cells adhering to the bottom of the culture plates, which prevents proper evaluation of potential adverse effects and leads to misinterpretation of toxicological assays. In this
review, we discuss the main issues related to the evaluation of micro- and nanoplastics toxicity using conventional in vitro assays. A literature survey has allowed to propose some solutions to circumvent these issues including the use of mathematical models to accurately determine the dose of particles delivered to cells, advanced 3D models (organoids), inverted cell culture models, cell cultures at the air-liquid interface or under dynamic conditions. Finally, we propose some perspectives and recommendations for further research on the in vitro evaluation of micro- and nanoplastics toxicity, underlining the importance of using standardized protocols for comparison purposes and samples and experimental conditions more representative of real-life exposure.