Bioaerosol

A bioaerosol is a biological aerosol. These particles are very small and range in size from less than one micrometer (0.00004") to one hundred micrometers (0.004"). Bioaerosols react to air currents and move quickly or slowly depending on the environment. Bioaerosols are impacted by gravity but due to their size air density and air currents play a large role in their movement.

Background
Air often contains tiny organisms such as fungi, bacteria, mycotoxins and viruses. None of these organisms live in the air but they are often attached to other small particles such as dried residues from water droplets, dust, soil or skin flakes. Groups of the small organisms clump up and enhance survival while airborn. Due to evaporation of water, bacterial cells usually die when they become airborn but under high humidity conditions bioaerosol levels are increased. Fungal cells such as spores, molds and yeast can be active at low humidity levels and high or low temperatures.

Collection
Many techniques are used to collect bioaerosols such as collection plates, electrostatic collectors and impactors, although some methods are experimental in nature. Another way to collect or detect bioaerosols is by using a mass spectrometer.