Background

Toxicity of silver nanoparticles (AgNP) has been studied frequently due to a rise in application in various products. Various studies on AgNP toxicity with terrestrial and aquatic organisms confirmed their negative effects. In our previous experiments, strong variability was observed in the reproduction of Collembola (Folsomia candida) in different repeats. To investigate the effects of silver on the reproduction of Folsomia candida, they were exposed in laboratory-controlled conditions to AgNP and silver nitrate (AgNO₃) at a concentration of 30 mg/kg dry soil for 28 days and compared to controlled individuals not exposed to silver. We repeated reproduction tests on the toxicity of silver to Folsomia candida four times throughout one year (April, July, October and January) in order to explore the temporal variability of their outcome.

Results

While adult survival was similar in all treatments and seasons, reproduction in the control increased from April to October. Significantly lower reproduction was found in January with only 385–424 juveniles per vessel, compared to 504–633 individuals in other months. Strong toxic effects of both silver treatments were observed in July, April and October. However, AgNP showed no toxic effects on the reproduction of F. candida in January. The relative toxicity of both substances varied between single experiments: AgNP were more toxic than AgNO₃ in April and July, and less toxic in October and January.

Conclusion

These findings indicate that the reproduction of F. candida in the control had a significant effect on the results of the toxicology experiments. Moreover, we demonstrated the reproductive toxicity of AgNP in soil at a much lower concentration than reported thus far. Therefore, to guarantee reliability and reproducibility, we recommend to disregard any test results where the reproduction rate of F. candida in the control is significantly different from the average in the respective laboratory, even if the validity criteria of the test are met.

中文翻译：

---

在银纳米颗粒，硝酸银和念珠菌（Collembola）的重复繁殖测试中，浓度效应低且结果不同

背景

由于在各种产品中应用的增加，银纳米颗粒（AgNP）的毒性已经得到了频繁的研究。关于AgNP对陆生和水生生物毒性的各种研究证实了它们的负面影响。在我们以前的实验中，在不同重复重复的Collembola（念珠菌）的繁殖中观察到了强烈的变异性。为了研究银对念珠菌繁殖的影响，在实验室控制的条件下将它们暴露于浓度为30 mg / kg干燥土壤的AgNP和硝酸银（AgNO ₃）中28天，并与未暴露的对照个体进行比较银。我们对银对念珠菌的毒性进行了多次繁殖试验 一年（四月，七月，十月和一月）四次，以探讨其结局的时间变异性。

结果

尽管所有治疗和季节的成年存活率都相似，但对照组的繁殖从4月到10月有所增加。一月份发现每只船只的幼鱼繁殖量明显较低，其他月份为504-633人，而每只幼稚鱼只有385-424个。分别在7月，4月和10月观察到两种银处理的强烈毒性作用。然而，AgNP对一月份念珠菌的繁殖没有毒性作用。两种物质的相对毒性在一次实验之间有所不同：AgNP在4月和7月比AgNO ₃毒性更高，在10月和1月的毒性更低。

结论

这些发现表明，对照中念珠菌的繁殖对毒理学实验的结果具有重大影响。此外，我们证明了AgNP在土壤中的生殖毒性远低于迄今报道的浓度。因此，为保证可靠性和可重复性，我们建议忽略即使对照的有效性达到标准的对照中念珠菌的繁殖率与各自实验室的平均值明显不同的任何测试结果。