Dust

dust

A general term used to describe dry solid particles suspended in the atmosphere that can range in size from submicron to several tens of microns. Dust can originate from a variety of sources: for example, soil, salt spray, smoke from forest fires and industrial sources, volcanic eruptions, extraterrestrial sources (i.e., meteor dust), and organic materials, such as bacteria, plant pollen, animal hairs, and human skin cells. It was once thought that dust particles were a main source of condensation nuclei; this is no longer regarded as probable, as most dusts are not sufficiently hygroscopic. Dust particles may travel thousands of kilometers and have severe global public health impacts, including bronchitis, asthma, lung cancer, and circulatory mortality.
Compare smoke, haze;
see duststorm, dust devil.

Term edited 14 October 2016.