Percorrer por autor "Santos, Mateus dos"
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- Assessment of exposure to the Penicillium glabrum complex in cork industry using complementing methodsPublication . Viegas, Carla; Sabino, Raquel; Botelho, Daniel; Santos, Mateus dos; Gomes, Anita QuintalCork oak is the second most dominant forest species in Portugal and makes this country the world leader in cork export. Occupational exposure to Chrysonilia sitophila and the Penicillium glabrum complex in cork industry is common, and the latter fungus is associated with suberosis. However, as conventional methods seem to underestimate its presence in occupational environments, the aim of our study was to see whether information obtained by polymerase chain reaction (PCR), a molecular-based method, can complement conventional findings and give a better insight into occupational exposure of cork industry workers. We assessed fungal contamination with the P. glabrum complex in three cork manufacturing plants in the outskirts of Lisbon using both conventional and molecular methods. Conventional culturing failed to detect the fungus at six sampling sites in which PCR did detect it. This confirms our assumption that the use of complementing methods can provide information for a more accurate assessment of occupational exposure to the P. glabrum complex in cork industry.
- Bacteria load a surrogate to assess occupational exposure to bioaerossols?Publication . Monteiro, Ana; Santos, Mateus dos; Faria, Tiago; Viegas, Carla; Cabo-Verde, SandraIn feed production, pug farms and swine slaughterhouses, the workers are exposure to bioaerosols. The aim of this study, was to asses occupational exposure to bacterial load (air and surfaces) in one feed production industry, in two pig farms and in one swine slaughterhouse. In addition, the authors intended also to analize the results together with the air fungal load already reported. Air samples were collected through an impcation method, while surface samples were collected by the swabbing method. The pig farms demonstrated to be the setting with the highest bacterial load. Bacterial load should not be a surragte to assess accupational exposure to bioaerosols, since bacterial and fungal load didn't present the same load trend, mainly in the feed industry and in clean and dirty slaughterhouse.
- Filters from taxis air conditioning system: a tool to characterize driver's occupational exposure to bioburden?Publication . Viegas, Carla; Monteiro, Ana; Santos, Mateus dos; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Gomes, Anita Quintal; Marchand, Geneviève; Lacombe, Nancy; Viegas, SusanaBioburden proliferation in filters from air conditioning systems of taxis represents a possible source of occupational exposure. The aim of this study was to determine the occurrence of fungi and bacteria in filters from the air conditioning system of taxis used for patient transportation and to assess the exposure of drivers to bioburden. Filters from the air conditioning systems of 19 taxis and 28 personal vehicles (used as controls) operating in three Portuguese cities including the capital Lisbon, were collected during the winter season. The occurrence and significance of bioburden detected in the different vehicles are reported and discussed in terms of colony-forming units (CFU) per 1 m2 of filter area and by the identification of the most frequently detected fungal isolates based on morphology. Azole-resistant mycobiota, fungal biomass, and molecular detection of Aspergillus species/strains were also determined. Bacterial growth was more prevalent in taxis (63.2%) than in personal vehicles (26.3%), whereas fungal growth was more prevalent in personal vehicles (53.6%) than in taxis (21.1-31.6%). Seven different azole-resistant species were identified in this study in 42.1% taxi filters. Levels of fungal biomass were above the detection limit in 63% taxi filters and in 75% personal vehicle filters. No toxigenic species were detected by molecular analysis in the assessed filters. The results obtained show that bioburden proliferation occurs widely in filters from the air conditioning systems of taxis, including the proliferation of azole-resistant fungal species, suggesting that filters should be replaced more frequently. The use of culture based-methods and molecular tools combined enabled an improved risk characterization in this setting.
- Fungal burden in waste industry: an occupational risk to be solvedPublication . Viegas, Carla; Faria, Tiago; Santos, Mateus dos; Carolino, Elisabete; Gomes, Anita Q.; Sabito, Raquel; Viegas, SusanaHigh loads of fungi have been reported in different types of waste management plants. This study intends to assess fungal contamination in one waste-sorting plant before and after cleaning procedures in order to analyze their effectiveness. Air samples of 50 L were collected through an impaction method, while surface samples, taken at the same time, were collected by the swabbing method and subject to further macro- and microscopic observations. In addition, we collected air samples of 250 L using the impinger Coriolis μ air sampler (Bertin Technologies) at 300 L/min airflow rate in order to perform real-time quantitative PCR (qPCR) amplification of genes from specific fungal species, namely Aspergillus fumigatus and Aspergillus flavus complexes, as well as Stachybotrys chartarum species. Fungal quantification in the air ranged from 180 to 5,280 CFU m−3 before cleaning and from 220 to 2,460 CFU m−3 after cleaning procedures. Surfaces presented results that ranged from 29 × 104 to 109 × 104 CFU m−2 before cleaning and from 11 × 104 to 89 × 104 CFU m−2 after cleaning. Statistically significant differences regarding fungal load were not detected between before and after cleaning procedures. Toxigenic strains from A. flavus complex and S. chartarum were not detected by qPCR. Conversely, the A. fumigatus species was successfully detected by qPCR and interestingly it was amplified in two samples where no detection by conventional methods was observed. Overall, these results reveal the inefficacy of the cleaning procedures and that it is important to determine fungal burden in order to carry out risk assessment.
- Horse stable environment: what to expect regarding fungi and particles occupational exposure?Publication . Viegas, Carla; Carolino, Elisabete; Meneses, Márcia; Santos, Mateus dos; Graça, Tiago; Viegas, SusanaThe simultaneous presence of fungi and particles in horse stable environment can create a singular exposure condition because particles have been reported has a good carrier for microorganisms and their metabolites. This study intends to characterize this setting and to recognize fungi and particles occupational exposure.
- Horse stable environment: what to expect regarding fungi and particles occupational exposure?Publication . Viegas, Carla; Carolino, Elisabete; Meneses, Márcia; Santos, Mateus dos; Graça, Tiago; Viegas, SusanaThe simultaneous presence of fungi and particles in horse stable environment can create a singular exposure condition because particles have been reported has a good carrier for microorganisms and their metabolites. This study intends to characterize this setting and to recognize fungi and particles occupational exposure.
- Microbiological assessment of indoor air quality at different hospital sitesPublication . Cabo Verde, Sandra; Almeida, Susana Marta; Matos, João; Guerreiro, Duarte; Meneses, Márcia; Faria, Tiago; Botelho, Daniel; Santos, Mateus dos; Viegas, CarlaPoor hospital indoor air quality (IAQ) may lead to hospital-acquired infections, sick hospital syndrome and various occupational hazards. Air-control measures are crucial for reducing dissemination of airborne biological particles in hospitals. The objective of this study was to perform a survey of bioaerosol quality in different sites in a Portuguese Hospital, namely the operating theater (OT), the emergency service (ES) and the surgical ward (SW). Aerobic mesophilic bacterial counts (BCs) and fungal load (FL) were assessed by impaction directly onto tryptic soy agar and malt extract agar supplemented with antibiotic chloramphenicol (0.05%) plates, respectively using a MAS-100 air sampler. The ES revealed the highest airborne microbial concentrations (BC range 240-736 CFU/m(3) CFU/m(3); FL range 27-933 CFU/m(3)), exceeding, at several sampling sites, conformity criteria defined in national legislation [6]. Bacterial concentrations in the SW (BC range 99-495 CFU/m(3)) and the OT (BC range 12-170 CFU/m(3)) were under recommended criteria. While fungal levels were below 1 CFU/m(3) in the OT, in the SW (range 1-32 CFU/m(3)), there existed a site with fungal indoor concentrations higher than those detected outdoors. Airborne Gram-positive cocci were the most frequent phenotype (88%) detected from the measured bacterial population in all indoor environments. Staphylococcus (51%) and Micrococcus (37%) were dominant among the bacterial genera identified in the present study. Concerning indoor fungal characterization, the prevalent genera were Penicillium (41%) and Aspergillus (24%). Regular monitoring is essential for assessing air control efficiency and for detecting irregular introduction of airborne particles via clothing of visitors and medical staff or carriage by personal and medical materials. Furthermore, microbiological survey data should be used to clearly define specific air quality guidelines for controlled environments in hospital settings.
- Microbiota and particulate matter assessment in Portuguese optical shops providing contact lens servicesPublication . Viegas, Carla; Faria, Tiago; Pacífico, Cátia; Santos, Mateus dos; Monteiro, Ana; Lança, Carla; Carolino, Elisabete; Viegas, Susana; Cabo-Verde, SandraThe aim of this work was to assess the microbiota (fungi and bacteria) and particulate matter in optical shops, contributing to a specific protocol to ensure a proper assessment. Air samples were collected through an impaction method. Surface and equipment swab samples were also collected side-by-side. Measurements of particulate matter were performed using portable direct-reading equipment. A walkthrough survey and checklist was also applied in each shop. Regarding air sampling, eight of the 13 shops analysed were above the legal requirement and 10 from the 26 surfaces samples were overloaded. In three out of the 13 shops fungal contamination in the analysed equipment was not detected. The bacteria air load was above the threshold in one of the 13 analysed shops. However, bacterial counts were detected in all sampled equipment. Fungi and bacteria air load suggested to be influencing all of the other surface and equipment samples. These results reinforce the need to improve air quality, not only to comply with the legal requirements, but also to ensure proper hygienic conditions. Public health intervention is needed to assure the quality and safety of the rooms and equipment in optical shops that perform health interventions in patients
- Occupational exposure assessment to particles with task-based approachPublication . Viegas, Susana; Almeida-Silva, Marina; Faria, Tiago; Santos, Mateus dos; Viegas, CarlaOccupational exposure assessment can be a challenge due to several factors being the most important the costs associate and the result's dependence from the conditions at the time of sampling. Conducting a task-based exposure assessment allow defining better control measures to eliminate or reduce exposure since more easily identifies the task with higher exposure. A research study was developed to show the importance of task-based exposure assessment in four different settings (bakery, horsemanship, waste sorting and cork industry). Measurements were performed using a portable direct-reading hand-held equipment and were conducted near the workers nose during tasks performance. For each task were done measurements of approximately 5 minutes. It was possible to detect the task in each setting that was responsible for higher particles exposure allowing the priority definition regarding investments in preventive and protection measures.
- Occupational exposure to Aflatoxin B1 in a Portuguese poultry slaughterhousePublication . Viegas, Susana; Veiga, Luísa; Almeida, Ana; Santos, Mateus dos; Carolino, Elisabete; Viegas, CarlaAflatoxin B1 (AFB1) is a secondary metabolite produced by the fungi Aspergillus flavus and is the most potent hepatocarcinogen known in mammals and has been classified by the International Agency of Research on Cancer as Group 1 carcinogen. Although dietary exposure to AFB1 has been extensively documented, there are still few studies dedicated to the problem of occupational exposure. Considering recent findings regarding AFB1 occupational exposure in poultry production, it was considered relevant to clarify if there is also exposure in poultry slaughterhouses. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Thirty workers from a slaughterhouse were enrolled in this study. A control group (n = 30) was also considered in order to know AFB1 background levels for Portuguese population. Fourteen workers (47.0%) showed detectable levels of AFB1 with values from 1.06 to 4.03ng ml(-1), with a mean value of 1.73ng ml(-1). No AFB1 was detected in serum of individuals used as controls. Despite uncertainties regarding the exposure route that is contributing more to exposure (inhalation or dermal) is possible to state that exposure to AFB1 is occurring in the slaughterhouse studied. It seems that reducing AFB1 contamination in poultry production can have a positive result in this occupational setting.