Microbes in schools with moisture damage affect respiratory symptoms

Exposure to microbes offers a partial, albeit incomplete explanation for the association between moisture damage and respiratory symptoms, according to a new publication from the HITEA project, led by the Finnish Institute for Health and Welfare (THL).

The study has been published in the scientific journal Indoor Air, said the THL in a press release on Wednesday.

For several decades, studies have been conducted aiming to identify specific microbes, toxins, or volatile organic compounds (VOC) that might explain the ill health of occupants of moisture damaged buildings, but with little success. It has become obvious that no individual factor can fully explain the adverse health symptoms caused by moisture damage.

People often link the harm caused by moisture damage to moulds, even though epidemiological studies indicate that moulds and their toxins offer only weak or inconsistent explanations for the adverse health effects.

In a recent analysis from the HITEA study, bacteria associated with moisture damage in Finnish school buildings were found to have a greater, even if still weak connection with respiratory symptoms in Finnish pupils, when compared to moulds. Many other factors affecting building occupant exposure may also be linked with moisture damage, such as chemical compounds and poor ventilation.

“The connection between moisture damage and respiratory symptoms can probably be explained by a combination of microbes and several other causes. When we breathe air, we are always exposed to many different compounds at the same time. In the future, the different risk factors of symptoms should be studied together within the same research, instead of studying one compound at a time. Nevertheless, it is good to remember that even though we do not know the precise mechanism that leads to adverse health effects caused by moisture damage in buildings, we know what to do: it is important to fix significant damage caused by moisture damage and to prevent its re-emergence”, said Martin Täubel, Chief Researcher at THL.

“Much research is needed to better understand the link between moisture damage and health. There is just no simple solution to this complex problem”, Täubel added.