What are bioaerosols? Bioaerosols are small particles (up to 100 µm) floating passively through the air. Various organisms like Bacteria, Fungi, Archaea, Protozoans or Viruses belong to them, but also fragments like dandruffs, tissue fragments or insect excretions. Another group of bioaerosols are dispersal units like spores from microorganisms or plant pollen.
Bioaerosols are important for everybody, who is living on Earth as well as for the Biosphere itself. Bioaerosols can, e.g., have an effect on the climate. Some airborne bacteria or fungi can act as so-called ice nuclei. These effect the formation of ice crystals or rain drops. On the other hand bioaerosols influence the diversity and dispersal of species as many species use the air to disperse and reach new habitats. Our planet certainly would look very different if the air did not serve as a transport medium for so many species.
However, bioaerosols also have effects that we do not like. Many people suffer, e.g., from pollinosis and react with allergic symptoms when confronted with plant pollen or allergenic fungi. Also many illnesses for humans and animals are dispersed via the air. Especially plant pathogens are transported with the air and every year tons of crops are lost due to infections with airborne fungi.
In my working group we try to better understand the world of bioaerosol. Within several projects we address the different questions individually. Which bioaerosols do we actually find in the air and in which proportions? How does the composition of bioaerosols within the air change depending on the seasonal cycles? Do meteorological parameters like temperature, relative humidity, rain or wind affect the composition? Where do bioaerosols actually come from, can we identify possible emission sources?
To address these questions we use molecular genetic and bio-informatic methods and analyse the DNA from the bioaerosols which have been collected on air filters.