Toxic Indoor Air Is a Potential Risk of Causing Immuno Suppression and Morbidity—A Pilot Study

Abstract

We aimed to establish an etiology-based connection between the symptoms experienced by the occupants of a workplace and the presence in the building of toxic dampness microbiota. The occupants (5/6) underwent a medical examination and urine samples (2/6) were analyzed by LC-MS/MS for mycotoxins at two time-points. The magnitude of inhaled water was estimated. Building-derived bacteria and fungi were identified and assessed for toxicity. Separate cytotoxicity tests using human THP-1 macrophages were performed from the office’s indoor air water condensates. Office-derived indoor water samples (n = 4/4) were toxic to human THP-1 macrophages. Penicillium, Acremonium sensu lato, Aspergillus ochraceus group and Aspergillus section Aspergillus grew from the building material samples. These colonies were toxic in boar sperm tests (n = 11/32); four were toxic to BHK-21 cells. Mycophenolic acid, which is a potential immunosuppressant, was detected in the initial and follow-up urine samples of (2/2) office workers who did not take immunosuppressive drugs. Their urinary mycotoxin profiles differed from household and unrelated controls. Our study suggests that the presence of mycotoxins in indoor air is linked to the morbidity of the occupants. The cytotoxicity test of the indoor air condensate is a promising tool for risk assessment in moisture-damaged buildings.

New approach methods for assessing indoor air toxicity

“…Several biological adverse effects were measured as well including cytotoxicity to THP-1 macrophages, induced IL-5 and IL-12p70 secretion, skin sensitization (DPRA and LuSens), and endocrine disruption. The health symptoms experienced, especially asthma and neurological symptoms are typical for mycotoxin exposure ( Ratnaseelan et al, 2018 , Vaali et al, 2022 ). In turn, the induction of IL-5 is associated with asthma ( Dougan et al, 2019 , Pelaia et al, 2019 ), and the induction of IL-12 p70 with the presence of mycoplasma ( Rosenblum Lichtenstein et al, 2015 ).…”

“…Firstly, because of the vast number of chemicals present: In 2021 WHO listed 90 compounds that are commonly encountered in the indoor air. The list included VOCs, heavy metals and pesticides, but in reality the list is longer because at least mycotoxins, which are also known to be present in the indoor air ( Bennett and Klich, 2003 , Nevalainen et al, 2014 ), and known to cause severe health effects ( Ratnaseelan et al, 2018 , Vaali et al, 2022 ), were missing. Hence, measuring the concentrations of all chemicals with potential health risks is virtually impossible.…”

“…In our previous investigations ( Hyvönen et al, 2020 , Mannerström et al, 2020 , Vaali et al, 2022 ) we introduced a method in which the cytotoxicity of water samples condensed from indoor air was studied in THP-1 macrophages using WST-1 assay (an indicator of mitochondrial activity). The advantage of collecting water samples from indoor air is that it represents indoor air as we inhale it.…”

Six Feet under Microbiota: Microbiologic Contamination and Toxicity Profile in Three Urban Cemeteries from Lisbon, Portugal

“…Other occupational settings have shown higher mycotoxins contamination that might be related with many factors, such as the occupational environment characteristics (e.g., humidity, temperature, and availability of fungal nutrients) and the raw materials being used and handled [ 18 , 31 ]. However, this mycotoxin has the potential for causing immune dysregulation that in the long run may be related to increased oncologic morbidity and susceptibility to infections [ 32 ].…”

“…Settled dust was collected through a vacuum cleaner (HOOVER Brave BV71_BV10 A2, Solon, OH, USA) with 1 × 4 collector filter attached (also used for further analyses) and a composite sample of the settled dust filters was obtained by vacuuming all the identified sampling sites [ 8 , 42 ]. Floor surfaces from the same sampling sites were swabbed following the same procedures already reported [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ] to allow microbial quantification. The EDC were placed above 1.5 m high on a shelf in each sampling site for 30 days.…”