Abstract
Several studies reported adverse respiratory health effects in workers exposed to ambient contaminants in bakeries. The aim of this study was to examine worker exposure to fungi and mycotoxins in Portuguese bakeries in order to develop new policies in occupational health. Environmental samples such as air, surfaces, settled dust and electrostatic dust collector (EDC) were collected in 13 bakeries for fungal and mycotoxins assessment. Air samples obtained by impaction were performed applying malt extract agar (MEA) supplemented with chloramphenicol (0.05%) and dichloran glycerol (DG18) agar-based media. Air samples collected through impinger method were determined as well for fungal detection by molecular tools of Aspergillus sections and mycotoxins. The highest median value for fungal load was 1053 CFU·m−3 and 65.3% (32 out of 49) of the sampling sites displayed higher fungal load than limits imposed by the World Health Organization. Aspergillus genera was found in air, surface swabs and EDC. Molecular tools were effective in measuring Aspergillus section Fumigati in 22.4% on air, 27.8% on surface swabs and in 7.4% in EDC and Aspergillus section Versicolores in one air sample. All settled dust samples showed contamination with six to eight mycotoxins in each sample. The mycotoxins detected were deoxynivalenol-3-glucoside, deoxynivalenol, zearalenone, 15-acetyldeoxynivalenol, monoacetoxyscirpenol, diacetoxyscirpenol, fumonisin B1, fumonisin B2, griseofulvin, HT2, ochratoxin A, ochratoxin B and mycophenolic acid. Industrial hygienists and exposure assessors should rely on different sampling methods (active and passive) and different assays (culture based and molecular methods) to obtain an accurate risk characterization regarding fungal burden (fungi and mycotoxins). Additionally, the awareness for the raw material as a potential mycotoxins indoor contamination source is important.
Highlights
Baking is a major industrial activity in Portugal and directly relates to the fact that Portuguese bread is a well-known product that is appreciated both nationally and internationally [1]
65.3% (32 out of 49) of the sampling sites showed higher fungal load than the limits imposed by the World Health Organization (WHO) [30] in 10 bakeries the indoor air load mean was higher than the outdoor fungal load (Figure 1) and 30 out of the 49 (61.2%) air samples collected presented higher fungal load when compared to the outdoor sampling
Similar results were found obtained in DG18, with fungal load ranging from 0 to 2620 CFU·m−3 and with Bakery 4 presenting the highest median value (1108 CFU·m−3), followed by Bakeries 1, 11, 8 and 12, with mean values of 887, 550, 518 and 480 CFU·m−3, respectively
Summary
Baking is a major industrial activity in Portugal and directly relates to the fact that Portuguese bread is a well-known product that is appreciated both nationally and internationally [1]. Without precise numbers, this implies a considerable work force involving many workers in this specific occupational environment in Portugal. In this setting ‘baker’s asthma’ is one of the most common work-related respiratory diseases. Wheat sensitization prevalence rates of up to 30% have been reported for bakers [2]. The environment of bakeries is very complex, and has several potential sensitizers among cereal flours such as wheat, rye or barley. The occurrence of sensitization to these allergens is less well known than those cases caused by cereal flours or enzymes, but they should be kept in mind in the clinical setting if no sensitization to common bakery allergens is found [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
