The rapid advancement of nanotechnology has led to the increasing application of metal oxide nanoparticles (NPs) in various fields, including agriculture, where they offer potential benefits such as improved nutrient delivery and pest control. However, concerns about their environmental impact necessitate a comprehensive assessment of their safety. This study investigated the potential toxic effects of iron-based nanoparticles (NPs) on freshwater planarian and the influence of abiotic factors such as humic acid (HA) and UV exposure on their toxicity. Three different types of iron-based NPs were tested, including commercially available Sigma iron oxide magnetic NPs (Sig_IOMNPs), biologically synthesized BS_IOMNPs and Zn–Fe and bulk FeSO₄. Sigma and biogenic nanoparticles had predominantly magnetite (Fe₃O₄) structure whereas Zn–Fe possessed a bimetallic conformation. Interaction of these NPs with abiotic factors (HA and UV light) led to an increase in their hydrodynamic diameter. In contrast to the commercial sources (Sig_IOMNPs and bulk FeSO₄), the biologically synthesized NPs did not cause any acute or sublethal toxicity to the planarian when alone or in combination with HA and UV. These results suggest that biologically synthesized iron-based NPs (Zn–Fe and BS_IOMNPs) may be a safe alternative to conventional bulk iron-based fertilizers. This study highlights the importance of investigating the physicochemical changes of NPs in environmentally realistic conditions and assessing their potential toxicity to aquatic organisms. These findings can contribute to the development of safe and sustainable agricultural practices, promoting the use of iron-based NPs as a new generation of fertilizers.

中文翻译：

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腐植酸和紫外线辐照对 Girardia tigrina 铁基纳米颗粒毒性的影响


纳米技术的快速发展导致金属氧化物纳米颗粒 （NPs） 在包括农业在内的各个领域的应用越来越多，它们提供了潜在的好处，例如改善营养输送和害虫防治。然而，由于担心其环境影响，因此需要对其安全性进行全面评估。本研究调查了铁基纳米颗粒 （NPs） 对淡水涡虫的潜在毒性作用，以及腐植酸 （HA） 和紫外线暴露等非生物因子对其毒性的影响。测试了三种不同类型的铁基 NP，包括市售的 Sigma 氧化铁磁性 NP （Sig_IOMNPs）、生物合成的 BS_IOMNPs 和 Zn-Fe 和块体 FeSO₄。Sigma 和生物纳米颗粒主要具有磁铁矿 （Fe₃O₄） 结构，而 Zn-Fe 具有双金属构象。这些 NP 与非生物因子 （HA 和 UV 光） 的相互作用导致其流体动力学直径增加。与商业来源（Sig_IOMNPs 和块体 FeSO₄）相比，生物合成的 NP 在单独使用或与 HA 和 UV 联合使用时不会对涡虫造成任何急性或亚致命毒性。这些结果表明，生物合成的铁基 NPs（Zn-Fe 和 BS_IOMNPs）可能是传统散装铁基肥料的安全替代品。本研究强调了在环境现实条件下调查 NP 的物理化学变化并评估其对水生生物的潜在毒性的重要性。 这些发现有助于发展安全和可持续的农业实践，促进铁基 NP 作为新一代肥料的使用。