As the production and usage of nanomaterials are increasing so are the concerns related to the release of the material into nature. Tungsten carbide (WC) is widely used for its hard metal properties, although its use, in for instance tyre studs, may result in nano-sized particles ending up in nature. Here, we evaluate the potential long-term exposure effects of WC nanoparticles on a pelagic (Daphnia magna) and a benthic (Asellus aquaticus) organism. No long-term effects were observed in the benthic system with respect to population dynamics or ecosystem services. However, long-term exposure of D. magna resulted in increased time to first reproduction and, if the particles were resuspended, strong effects on survival and reproductive output. Hence, the considerable differences in acute vs. long-term exposure studies revealed here emphasize the need for more long-term studies if we are to understand the effects of nanoparticles in natural systems.

中文翻译：

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碳化钨（WC）纳米颗粒对中上层和底栖水生生态系统的长期影响

随着纳米材料的生产和使用的增加，与将材料释放到自然中有关的关注也在增加。碳化钨（WC）因其坚硬的金属性能而被广泛使用，尽管在轮胎螺柱中使用碳化钨可能会导致纳米级颗粒最终出现在自然界中。在这里，我们评估了WC纳米颗粒对浮游生物（Daphnia magna）和底栖生物（Asellus aquaticus）的潜在长期暴露影响。在底栖系统中，没有观察到对种群动态或生态系统服务的长期影响。。然而，长期接触大型溞导致初次繁殖的时间增加，如果将颗粒重悬，则会对存活和繁殖产量产生重大影响。因此，这里揭示的急性与长期暴露研究的显着差异强调，如果我们要了解纳米粒子在自然系统中的作用，则需要进行更多长期研究。