The airborne mycobiome and associations with mycotoxins and inflammatory markers in the Norwegian grain industry

Abstract

Grain dust exposure is associated with respiratory symptoms among grain industry workers. However, the fungal assemblage that contribute to airborne grain dust has been poorly studied. We characterized the airborne fungal diversity at industrial grain- and animal feed mills, and identified differences in diversity, taxonomic compositions and community structural patterns between seasons and climatic zones. The fungal communities displayed strong variation between seasons and climatic zones, with 46% and 21% of OTUs shared between different seasons and climatic zones, respectively. The highest species richness was observed in the humid continental climate of the southeastern Norway, followed by the continental subarctic climate of the eastern inland with dryer, short summers and snowy winters, and the central coastal Norway with short growth season and lower temperature. The richness did not vary between seasons. The fungal diversity correlated with some specific mycotoxins in settled dust and with fibrinogen in the blood of exposed workers, but not with the personal exposure measurements of dust, glucans or spore counts. The study contributes to a better understanding of fungal exposures in the grain and animal feed industry. The differences in diversity suggest that the potential health effects of fungal inhalation may also be different.

Occupational inhalant allergy in food handling occupations

“…Furthermore, mycotoxin exposures have also been reported in Portuguese fresh bread dough companies [43], documenting exposures to deoxynivalenol (DON) as high as 58.2 ng/g, whilst a study in the Norwegian grain industry reported 1,3-β-glucan concentrations of 32 μg/m 3 [44]. A study of Irish bakeries and pizzerias reported fungi including Penicillium and mycotoxin exposures dominated by DON [41].…”

Development of a Generic PBK Model for Human Biomonitoring with an Application to Deoxynivalenol

“…The main route of exposure to mycotoxins in an occupational setting is via inhalation as mycotoxins can be present in organic dust. For instance, exposure can occur during the development of working routines in different types of industries (e.g., brewing and bakeries) or during the interaction with feed [ 1 , 2 , 3 , 4 , 5 , 6 ].…”

Mycobiota recovered from the trachea and lungs of pigeons (Columba livia) captured in a grain mill

“…Their granivorous habits affect in natura or industrialized grain-food industries from the processing to the final consumer, besides the importance as a vector of pathogens (Ferreira et al, 2016). Studies are scarce about the dust from activity in grain mill, which is the main responsible for respiratory clinical conditions in workers in these industries (Straumfors et al, 2021), as well as in the surrounding community (Theisinger;Smidt, 2017;Permatasari & Kolibu, 2020), being fungi important etiological agents involved in these processes.…”

“…High concentrations of airborne fungi were identified at the grain mill from Lithuania, where allergenic genus such as Penicillium, Cladosporium and Geotrichum prevailed (Straumfors et al, 2021). Thus, it is possible that fungal propagules have been inhaled by the birds, indicating, therefore, that they could also be inhaled by grain mill workers and cause acute respiratory symptoms through occupational exposure by the inhalation of large fungal inoculum (Theisinger & Smidt, 2017;Permatasari & Kolibu, 2020;Straumfors et al, 2021).…”

“…High concentrations of airborne fungi were identified at the grain mill from Lithuania, where allergenic genus such as Penicillium, Cladosporium and Geotrichum prevailed (Straumfors et al, 2021). Thus, it is possible that fungal propagules have been inhaled by the birds, indicating, therefore, that they could also be inhaled by grain mill workers and cause acute respiratory symptoms through occupational exposure by the inhalation of large fungal inoculum (Theisinger & Smidt, 2017;Permatasari & Kolibu, 2020;Straumfors et al, 2021). All fungi isolated from the respiratory tract of pigeons are saprophytic and coexist on diverse organic matters, and the majority is considered as potentially pathogenic and involved in acute respiratory symptoms, increasing the possibility of interfering in the health of workers or the surrounding community (Senbeta & Gure, 2014;Pelliser et al, 2016;Theisinger & Smidt, 2017).…”