Aerosol nanoparticles play an important role in the climate system by affecting cloud formation and properties, as well as in human health because of their deep reach into lungs and the circulatory system. Determining nanoparticle sources and composition is a major challenge in assessing their impacts in these areas. The sudden appearance of large numbers of atmospheric nanoparticles is commonly attributed to secondary formation from gas-phase precursors, but in many cases, the evidence for this is equivocal. We report the detection of a mode of fungal fragments with a mobility diameter of roughly 30 nm released in episodic bursts in ambient air over an agricultural area in northern Oklahoma. These events reached concentrations orders of magnitude higher than other reports of biological particles and show similarities to unclarified events reported previously in the Amazon. These particles potentially represent a large source of both cloud-forming ice nuclei and respirable allergens in a variety of ecosystems.

中文翻译：

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大气真菌纳米粒子爆发。

气溶胶纳米颗粒通过影响云的形成和性质，以及对人体健康的影响，在气候系统中起着重要作用，因为它们可以深入肺部和循环系统。在评估纳米粒子在这些领域的影响时，确定纳米粒子的来源和组成是一项重大挑战。大气中大量纳米颗粒的突然出现通常归因于气相前体的二次形成，但在许多情况下，其证据是模棱两可的。我们报告了在俄克拉荷马州北部一个农业地区的环境空气中的突发性发作中释放出的具有约30 nm迁移直径的真菌片段的模式的检测。这些事件的浓度比其他生物颗粒报告的浓度高出几个数量级，并且显示出与先前亚马逊地区报告的未阐明事件的相似之处。这些颗粒可能代表着各种生态系统中形成云的冰核和可吸入的过敏原的大量来源。