People exposed to mould indoors and at workplaces are at increased risk of developing respiratory illness. A possible cause of mould infestation’s health effects are inflammatory processes of the upper respiratory tract and lungs. These can be triggered by bioaerosols.
Bioaerosols are airborne particles. They can be comprised of pollen, bacterial cells and cellular fragments, fungal spores and fungal hyphae, viruses and by-products of microbial metabolisms. In terms of their size, shape and constituents, bioaerosol particles are very complex. They occur everywhere and can easily reach the lungs via the respiratory tract. Many components of bioaerosols, including mould spores, can even get deep into the airways due to their small diameter of less than ten micrometers. In this way, moulds and adherent toxins (mycotoxins) are recognized by our immune cells as invaders. Thus, they can cause irritant and possibly immune-altering effects and be a trigger for inflammatory processes in the lungs.
So far, there is no valid test system to analyze the overall health effects of bioaerosols. For this reason, it is currently not possible to assess the health risks of exposure in mould-contaminated interiors or workplaces and to set limit values on a case-by-case basis.
The aim of this project is to develop a test system to assess the harmful effects on the lungs by components of bioaerosols using the example of moulds. One way to detect such biological effects are in vitro approaches with cell cultures, i.e. the cultivation of human cells in a culture medium outside the organism. Cell cultures can provide indications regarding the effect of a wide variety of substances, materials and substances in terms of their toxic or allergenic strength and therefore provide a good way to assess the potential effect on humans.
In the new test system, moulds and their toxic components are first isolated from material samples used indoors. For this purpose, contaminated materials such as wallpapers and plasterboards are used. Then human lung and immune cells are exposed to the collected samples. Subsequently, the degree of cell damage is investigated using various methods. Through the combination of detecting toxic constituents and examining the effect, a statement on the toxic potential of contaminated indoor air should be possible. Such test systems could be used in the future to assess the health risks from mould infestation indoors and at workplaces in specific cases.
The project is being carried out on behalf of the Federal Environment Agency (Department Research Plan 2018).
Unit 4.7 "Biological Agents"