In a potentially worrisome development for those of us who breathe, chemists from the University of California, Irvine report that they’ve found fragments of fungal cells in the atmosphere. The pieces are extremely small, measuring about 30 namometers in diameter, and much more abundant that previously thought, the researchers said in a study published this week in Science Advances. https://advances.sciencemag.org/content/6/3/eaax9051.