Department of Life Sciences, University of Trieste, I-34127 Trieste, Italy.
Department of Life Sciences, University of Trieste, I-34127 Trieste, Italy; Department of Chemical and Pharmaceutical Sciences, University of Trieste, I-34127 Trieste, Italy.
Sci Total Environ. 2022 Jul 15;830:154625. doi: 10.1016/j.scitotenv.2022.154625. Epub 2022 Mar 16.
Products containing graphene-related materials (GRMs) are becoming increasingly common, allowing GRM nanoparticles (NPs) to enter the environment during their life cycle. Thanks to their lightness and bidimensional geometry, GRM NPs can be easily dispersed in the air and travel very long distances. The flowers of wind-pollinated plants may be exposed to airborne GRMs, being apt to intercept pollen from the air and, inevitably, other airborne particles. Here, stigmas of four wind-pollinated plants (Corylus avellana, common hazel; Juglans regia, walnut; Quercus ilex, holm oak; Zea mays, maize) were exposed to airborne graphene oxide (GO) and GO purified from production residues (PGO) at a concentration of 3.7 ng m. Subsequently, the stigmas were pollinated and the adhesion of GOs and their effects on stigma integrity and pollen-stigma interaction were examined. The effect of GO NPs in presence of liquid water on the stigma of C. avellana was also investigated. GOs NPs were intercepted by all species, but their effect varied among them. GO reduced pollen adhesion in J. regia and Q. ilex, whereas pollen germination was unaffected in all four species. The presence of a film of water neither completely removed GO NPs from the stigma, nor it enhanced the toxic effect of GO acidity. PGO never affected pollen-stigma interaction, indicating that the phytotoxic substances used for the production of GO, still in traces in commercial GO, are the main cause of GO toxicity. These results reconfirm the need to verify GRMs effects also on key biological processes beside single model organisms.
含有石墨烯相关材料（GRMs）的产品越来越常见，这使得 GRM 纳米颗粒（NPs）在其生命周期中进入环境。由于其轻盈和二维几何形状，GRM NPs 很容易在空气中分散，并能传播很远的距离。风媒植物的花朵可能会暴露于空气中的 GRMs 中，容易拦截空气中的花粉，以及不可避免的其他空气传播颗粒。在这里，四种风媒植物（榛子、胡桃、栓皮栎、玉米）的柱头暴露于空气中的氧化石墨烯（GO）和从生产残留物中纯化的 GO（PGO）中，浓度为 3.7ng m。随后，柱头被授粉，并检查了 GO 的附着及其对柱头完整性和花粉柱头相互作用的影响。还研究了在存在液态水的情况下 GO NPs 对 C. avellana 柱头的影响。所有物种都拦截了 GO NPs，但它们的影响在物种之间有所不同。GO 减少了 J. regia 和 Q. ilex 中的花粉附着，而在所有四个物种中，花粉萌发均未受影响。水膜的存在既不能完全从柱头上清除 GO NPs，也不能增强 GO 酸度的毒性作用。PGO 从未影响花粉柱头相互作用，表明用于生产 GO 的植物毒性物质，尽管仍在商业 GO 中存在微量，但仍是 GO 毒性的主要原因。这些结果再次证实，需要在除了单一模式生物之外的关键生物过程中验证 GRMs 的影响。
