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- Sampling protocol to assess Aspergillus section Fumigati in woodworking environmentsPublication . Dias, Marta; Gomes, Bianca; Pena, Pedro; Cervantes, Renata; Rodriguez, Margarida; Riesenberger, Bruna; Marques, Liliana; Ribeiro, Edna; Viegas, CarlaPortugal’s wood industry employs over 80,000 people and comprises about 16,600 enterprises in 2021. Sawmill workers are exposed to several occupational hazards, including microorganisms. Health problems have been documented by workers exposed to wood dust infected with fungi. A fungal priority pathogens list (WHO FPPL) was recently released by the WHO. It prioritizes fungal pathogens based on their perceived public health importance and unmet research and development needs. Some of the species on this list are frequently found in sawmills. Azole fungicides are commonly used by sawmills to protect wood. Aspergillus section Fumigati azole antifungal resistance has previously been observed in this environment. This study aimed to establish a sampling protocol to effectively isolate Aspergillus section Fumigati in woodworking environments.
- Budget-friendly protocol for TR34/L98H and TR46/Y121F/T289A mutation detection in Aspergillus section Fumigati isolatesPublication . Dias, Marta; Rodriguez, Margarida; Vasques, C.; Riesenberger, Bruna; Marques, Liliana; Gomes, Bianca; Pena, Pedro; Cervantes, Renata; Viegas, Susana; Viegas, CarlaAspergillus section Fumigati is one of the most common sections, in the environment. It has been found in different occupational environments, such as sawmills and waste sorting. Its cryptic species show intrinsic resistance to several antifungals. Resistance in A. fumigatus is emerging due to selective pressure caused by the prolonged use of azoles. It is often associated with mutations in the Cyp51A gene. The fungal priority pathogens list (WHO), includes A. fumigatus with critical priority. Further analysis to identify potential resistance mechanisms and mutations is needed. Objective: This evaluation aims to offer a protocol for mutation detection in Aspergillus section Fumigati isolates. It will contribute to the development of guidance that can support future occupational exposure assessments.
- Commercial tea samples: a natural health ally or an Aspergillus infusionPublication . Gomes, Bianca; Dias, Marta; Cervantes, Renata; Caetano, Liliana Aranha; Viegas, CarlaIntroduction and Purpose - Tea consumption has been increasing in the last few years. The lack of specific legislation concerning microbial contamination of teas and infusions might represent a risk for consumers’ health. This study characterizes fungal contamination and azole resistance on green and black tea and other infusions commercially available in Portugal.
- The effects of mechanical alloying on the physical and thermal properties of CuCrFeTiV alloyPublication . Antão, F.; Dias, Marta; Correia, J. B.; Galatanu, Andrei; Galatanu, M.; Mardolcar, U. V.; Myakush, A.; Cruz, Maria Margarida; Casaca, António; da Silva, R. C.; Alves, E.The present work reports the production and key properties of the CuCrFeTiV high entropy alloy synthetized mechanical alloying and spark plasma sintering. The milled powders and the as-sintered samples were analysed through scanning electron microscopy, coupled with energy dispersive X-ray spectroscopy and particle induced X-ray emission. Magnetic properties together with electrical resistivity, thermal conductivity, specific heat differential thermal analysis were also evaluated on the consolidated samples. The powders reveal an increasing content in iron as the millings are prolonged up to 20 h. The elemental composition of the sintered alloy, determined through particle induced X-ray emission, confirms the final composition after mechanical alloying with an increase of iron and a decrease in the remaining elements. Furthermore, although the alloy presents electrical resistivity typical of a high entropy alloy, a ferromagnetic behaviour was found, consistently with major Fe content as detected in prior observations. Finally, thermal measurements show that this CuCrFeTiV entropy alloy possesses thermal properties suitable for its potential use as thermal barriers.
- Fungal contamination in Lisbon’s primary schools: sampling insights and analytical approachesPublication . Cervantes, Renata; Pena, Pedro; Gomes, Bianca; Dias, Marta; Riesenberger, Bruna; Rodriguez, Margarida; Marques, Liliana; Viegas, CarlaClimate change is posing challenges for Portugal due to intense weather changes, affecting public health and causing pathogens to adapt and spread, increasing the global risk of infectious diseases. Azole fungicides are less effective against resistant fungi, raising concerns for children. Warm and humid conditions promote the growth of pathogenic fungi and the production of mycotoxins, impacting health by causing gastrointestinal problems, organ damage, and chronic diseases Even after fungi removal, mycotoxins continue to pose risks. Objectives: identifying fungal species present in indoor environments; assessing the spatial distribution and concentration levels within classrooms and other areas; investigating factors influencing fungal proliferation, such as building characteristics and seasonal variations; evaluating the effectiveness of existing cleaning protocols and providing insights into proactive management strategies to protect students and staff members' health and well being.
- Occupational exposure to fungi and mycotoxins: overview of different studies developed in PortugalPublication . Viegas, Carla; Cervantes, Renata; Dias, Marta; Gomes, Bianca; Pena, Pedro; Carolino, Elisabete; Twarużek, Magdalena; Kosicki, Robert; Soszczyńska, Ewelina; Caetano, Liliana Aranha; Viegas, SusanaAs in all European countries, Portuguese employers are obliged by legal requirements to assess and prevent exposure to chemical, physical and biological risks (Directive 89/391/EEC). However, the health risks of biological origin are frequently less recognized and, thus, underreported. This study intends to present an overview of the assessments of fungal contamination and mycotoxins performed in three different occupational environments (Firefighters headquarters - FFH; Waste collection trucks – WCT and; Cemeteries - CM). Active sampling (impaction and impingement methods) and several passive sampling methods (swabs, settled dust, settled dust filters, electrostatic dust cloths – EDC, cleaning materials,…) were employed. Azole resistance screening, the molecular detection of Aspergillus sections, as well as mycotoxin analysis were also conducted. Regarding FFH it was raised concern regarding the following findings: a) microbial contamination didn´t comply with Portuguese IAQ legal requirements in most of the FFH (fungal load 45.45%); b) fungal exposure through inhalation underlining a possible risk factor for respiratory diseases; c) prevalence of Aspergillus sp. in cleaning materials that might represent a potential source of cross-contamination; d) widespread of Aspergillus section Fumigati in all the FFH analysed; e) trend of multidrug resistance found among fungi with a focus on Fumigati isolates; and f) detection of several mycotoxins (fumonisin B2, nivalenol, mycophenolic acid, and sterigmatocystin). Concerning WCT Aspergillus sp. (4.18%) was one of the most prevalent species. Aspergillus section Fumigati was detected in 5 samples. Mycotoxins were detected in filters (N=1) and in settled dust samples (N=16). The mycotoxin detected in the filter was fumonisin B1 and the most detected in settled dust was mycophenolic acid. Sterigmatocystin, deoxynivalenol, and zearalenon were detected in only one sample each. In what concerns CM, Aspergillus sp. presented the highest counts in DG18 (18.38%) and it wasn't observed in azole-supplemented SDA media. Mycophenolic acid was detected in one settled dust sample. Overall, our study reveals that a comprehensive sampling approach using active and passive sampling methods and combined analytic methods (i.e., culture-based and molecular) is an important asset in microbial exposure assessments. Furthermore, in all three occupational environments mycotoxins were detected unveiling this occupational health threat.
- Aspergillus distribution on waste collection trucksPublication . Dias, Marta; Pena, Pedro; Cervantes, Renata; Gomes, Bianca; Caetano, Liliana Aranha; Viegas, CarlaIntroduction: While better waste management is viewed as a critical contributor to reducing health outcomes and harmful environmental impacts, microbiological occupational exposure in the waste management industry is often overlooked, resulting in detrimental health effects on employees. Some waste workers, such as garbage collectors and truck drivers transporting the residential waste, spend part of their shift in a truck cabin and part of it in a workplace where organic materials are processed. The aim of this study was to investigate the Aspergillus spp. contamination present in 32 waste collection trucks (WCT).
- Development of an indexed score to identify the most suitable sampling method to assess occupational exposure to fungiPublication . Cervantes, Renata; Dias, Marta; Gomes, Bianca; Carolino, Elisabete; Viegas, CarlaThe sampling approach is of utmost importance to obtain data regarding microbial viability and truly assess workers’ potential health effects. The purpose of this assessment is to create a score that will provide up-to-date information to identify the most suitable sampling method to assess occupational exposure to fungi. Data from a sampling campaign performed at Firefighters Headquarters (FFH) was analyzed and a score was calculated from one (1) to three (3) for five (5) distinct sample parameters: (a) accuracy; (b) complexity of the fieldwork; (c) cost; (d) complexity in laboratory work; and (e) time is taken since the fieldwork until obtaining the fungal contamination characterization. The statistical analysis allowed us to conclude that settled dust and Andersen's six-stage were the best sampling methods to perform the assessment of the occupational exposure to fungi at FFH when considering the number of species. As for the final score, the results showed that surface swabs were the best sampling method. The results obtained for surface swabs highlight the low complexity of this processing combined with the fact that it is a low-cost sampling method. This study reinforces the need to use a wide array of sampling methods when assessing occupational exposure to fungal contamination to ensure an accurate risk characterization.
- Unveiling the occupational exposure to microbial contamination in conservation-restoration settingsPublication . Viegas, Carla; Cervantes, Renata; Dias, Marta; Gomes, Bianca; Pena, Pedro; Carolino, Elisabete; Twarużek, Magdalena; Kosicki, Robert; Soszczyńska, Ewelina; Viegas, Susana; Caetano, Liliana Aranha; Pinheiro, Ana CatarinaAssuring a proper environment for the fulfillment of professional activities is one of the Sustainable Development Goals and is contemplated in the One Health approach assumed by the World Health Organization. This particular study is applied to an often neglected sector of our society—the conservators/restorers—despite the many health issues reported by these professionals. Three different specialties (textiles, paintings, and wood sculptures) and locations were selected for evaluation by the placement of electrostatic dust cloths. After treatment of the samples, bacterial and fungal contamination was assessed, as well as mycotoxin determination, the presence of azole-resistant strains, and cytotoxicity of the microorganisms encountered. Bacteria were only present in one of the media used and showed relatively low numbers. The highest level of contamination by fungi was identified in one of the textiles settings. The textile area also showed the highest variability for fungi. Aspergillus sp. is one indicator of possible environmental issues, and A. sections Fumigati and Circumdati were particularly relevant in two of the settings and identified in all of them. No mycotoxins were detected and the large majority of the fungi identified were non-cytotoxic. Overall, these can be considered low-contaminated environments but attention should be given to the Aspergillus sp. contamination. Additional studies are needed not only to make these results more robust but also to test if the environmental sampling alone is the best approach in a setting where there is very little movement and dust displacement and where professionals are in very close proximity to the artifacts being treated, which may suggest the existence of a micro-atmosphere worth evaluating and comparing to the obtained results.
- Exposure to azole-resistant Aspergillus fumigatus in Portuguese sawmillsPublication . Dias, Marta; Gomes, Bianca; Pena, Pedro; Cervantes, Renata; Caetano, Liliana Aranha; Carolino, Elisabete; Viegas, CarlaSawmill workers have an increased risk of adverse respiratory health effects due to wood dust, microorganisms, and metabolite exposure. Knowledge about exposure-response relationships is scarce, with information lacking regarding this transformation sector in Portugal. Among microbial components, fungi and fungal spores and fragments stand as allergens and irritants, due to their high prevalence, under the right circumstances, on wood products (planks, chips) that have been preserved. Aspergillus species can infect the lungs, causing pneumonia-like symptoms that can progress into more severe sickness and are reported as the most common found in sawmills. Moreover, Aspergillus section Fumigati has recently entered the WHO ranking list of most critical fungal pathogens, based on the impact of the fungal disease on public health. While antifungal resistance has been reported in sawmills, there is no data, to date, on occupational exposure to azole-resistant Aspergillus fumigatus (ARAF) in Portuguese sawmills. This study aims to determine the prevalence of azole-resistant Aspergillus fumigatus, followed by the characterization of the distribution of azole-resistance mutations in Aspergillus fumigatus from Portuguese sawmills. The correlation of the exposures with work tasks handled wood products, and seasonal variation will also be made to suggest the most suitable procedures to ensure sawmill workers’ safety.