Percorrer por autor "Grajewski, Jan"
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- Are workers from waste sorting industry really protected by wearing filtering respiratory protective devices? The gap between the myth and realityPublication . Viegas, Carla; Dias, Marta; Almeida, Beatriz; Aranha Caetano, Liliana; Carolino, Elisabete; Gomes, Anita Quintal; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Marchand, Geneviève; Viegas, SusanaOne of the solutions for decreasing the workers' exposure to bioburden is the use of Filtering Respiratory Protective Devices (FRPD). As such it is important to determine whether these devices are fulfilling their protective role. This is the basis of the current study, aimed at characterizing bioburden retained by 120 FRPD (both in interior layers and in exhalation valves) through culture based-methods and molecular tools and also via analysis of antifungal resistance and mycotoxins profile. Our results show that Gram–Bacteria are present at a higher prevalence than total bacteria in both matrixes. Regarding fungal identification, Chrysonilia sitophila presented the highest prevalence on interior layers (55.1% on malt extract agar (MEA) supplemented with chloramphenicol (0.05%); 59.6% on dichloran-glycerol agar (DG18)), whereas on exhalation valves Aspergillus sp. presented the highest prevalence on MEA (6.8%) and C. sitophila on DG18 (36.3%). Among Aspergillus genera, section Fumigati was the one with the highest prevalence in both matrices. Aspergillus sp. was the most prevalent on exhalation valves (75.0% ITRA) in the screening of azole resistance. Fumigati section was the most abundant Aspergillus sp. detected on the interior layers (33.33%, 40 samples out of 120) and on the exhalation valves (1.66%, 2 samples out of 120). The interior layers and exhalation valves from workers with more waste contact showed an increased exposure to bioburden. This study showed that FRPD can have high levels of bioburden, toxigenic fungal strains and Aspergillus sections with reduced susceptibility to the tested azoles and can be used as a passive sampling method since it mimics the results obtained by active methods in previous studies. The gathered information will be useful to prioritize multiple interventions on workers’ education or even on FRPD replacement frequency.
- Assessment of the microbial contamination of mechanical protection gloves used on waste sorting industry: a contribution for the risk characterizationPublication . Viegas, Carla; Twarużek, Magdalena; Dias, Marta; Almeida, Beatriz; Carolino, Elisabete; Kosicki, Robert; Soszczyńska, Ewelina; Grajewski, Jan; Aranha Caetano, Liliana; Viegas, SusanaIn Portugal, mechanical protection gloves (MPG) are of mandatory use and during their use sweat is released and, consequently, the humidity of the material increases leading to conditions favorable to the growth of microorganisms. However, no studies have been conducted in MPG to assess the bioburden. This study intended to determine the bioburden present in MPG and their biological effects and to discuss the possibility to use MPG as a passive method to assess occupational exposure to microbial contamination. Fungal burden was characterized through molecular tools for fungal toxigenic species, and antifungal resistance and mycotoxin profiles were determined. Cell viability was determined in swine kidney (SK) monolayer and hepatocellular carcinoma (Hep G2) cell lines. All MPG samples presented Gram-negative bacteria. The fungal contamination ranged from 0 CFU.m−2 in both MEA and DG18, to 5.09 × 106 and 2.75 × 106, and the most common fungi found was Aspergillus spp. (50.46%). Azole resistant Aspergillus sections were found in azole supplemented media. Aspergillus sections (Circumdati, Flavi, Fumigati and Versicolores) were detected by molecular tools in 66 out of 67 samples. The most-reported mycotoxin was mycophenolic acid (89.6%). HepG2 cells appear to be more sensitive to MPG contamination, with high cytotoxicity (IC50 < 0.05 mm2/ml) observed for 18 out of 57 gloves. MPG can be used in passive sampling to assess occupational exposure to bioburden in waste sorting industries and contribute to risk characterization. Some contaminants of MPG had cytotoxic potential and affected the biology of hepatic cells more than renal cells.
- Characterization of the bioburden in green tea samples marketed in LisbonPublication . Viegas, Susana; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Santos, Patrícia; Sá, Flávio; Mateus, Margarida; Viegas, CarlaTea is one of the most consumed beverages in the world essentially because of its beneficial effects on health. There are no regulations or load limits concerning microbial contamination of teas, and for this reason, microbiological food safety hazards linked with these products have rarely been reported. The aim of this study was to assess the bioburden of loose and bags tea of green tea marketed in Lisbon, after and before boiling following the ISO 7218 (2007) and ISO 3103 (1980). Twenty samples of green tea from loose and bag tea (ten of each) were select from different markets in Lisbon. For microbiological evaluation was carried out the extraction of the samples before and after the boiling. For samples that did not have manufacturer confection indications were followed by ISO 7218_2007. The samples were inoculated on two media: dichloro-glycerol agar (DG18) and Rose Bengal Chloramphenicol (RBC) incubated for 5 days at 25ºC. All tea samples will be screened for mycotoxins presence. Regarding fungal contamination in tea bags, before boiling, ranged from 0 to 66.67 CFU.g-1 in DG18, and from 0 to 84.85 CFU.g-1 in RBC medium. In tea bags, all brew samples present 0 CFU.mL-1 for the two medium. For loose tea before boiling, the fungal contamination ranged from 0 to 96.97 CFU.g-1, and after boiling ranged from 0 to 30.3 CFU.mL-1 in DG18. In RBC, before boiling, the fungal concentration ranged from 0 to 72.73 CFU.g-1 and the brew samples presented 0 CFU.mL-1 or were below the limit of determination after boiling. In loose tea samples, before boiling, the DG18 media show five different fungal genera/species and the most prevalent were Chrysosporium sp. (38.46%), Aspergillus section Nigri (30.76%) and section Versicolores (11.5%), whereas in RBC media two different fungal species were found, Aspergillus section Nigri (80%) and Penicillium sp. (20%). After boiling only the DG18 presented fungal contamination: Mucor sp. (80%) and Chrysonilia sitophila (20%). Concerning tea bags samples, before boiling, Aspergillus section Nigri was the most prevalent fungi in both media (90.47% DG18; 90.62% RBC). None of the bag samples showed fungal contamination after boiling. This study showed that after boiling was observed reduction of viable microorganisms, revealing that boiling is effective to reduce most bioburden present in the tea before boiling. However, due to the presence of toxigenic species in the tea before boiling and the well-known mycotoxins thermal resistance, mycotoxins data will be of interest to consider a more accurate risk assessment.
- Exposure assessment in one central hospital: a multi-approach protocol to achieve an accurate risk characterizationPublication . Viegas, Carla; Almeida, Beatriz; Monteiro, Ana; Paciência, Inês; Rufo, João; Aguiar, Lívia; Lage, Bruna; Diogo Gonçalves, Lídia Maria; Aranha Caetano, Liliana; Carolino, Elisabete; Gomes, Anita Quintal; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Teixeira, João Paulo; Viegas, Susana; Pereira, CristianaThe bioburden in a Hospital building originates not only from patients, visitors and staff, but is also disseminated by several indoor hospital characteristics and outdoor environmental sources. This study intends to assess the exposure to bioburden in one central hospital with a multi-approach protocol using active and passive sampling methods. The microbial contamination was also characterized through molecular tools for toxigenic species, antifungal resistance and mycotoxins, and endotoxins profile. Two cytotoxicity assays (MTT and resazurin) were conducted with two cell lines (Calu-3 and THP-1), and in vitro pro-inflammatory potential was assessed in the THP-1 cell line. Out of the 15 sampling locations, 33.3% did not comply with Portuguese legislation regarding bacterial contamination, whereas concerning fungal contamination 60% presented I/O > 1. Toxigenic fungal species were observed in 27% of the sampled rooms (4 out of 15) and qPCR analysis successfully amplified DNA from the Aspergillus sections Flavi and Fumigati, although mycotoxins were not detected. Growth of distinct fungal species was observed on Sabouraud dextrose agar with triazole drugs, such as Aspergillus section Versicolores on 1 mg/L VORI. The highest concentrations of endotoxins were found in settled dust samples and ranged from 5.72 to 23.0 EU.mg−1. While a considerable cytotoxic effect (cell viability < 30%) was observed in one HVAC filter sample with the Calu-3 cell line, it was not observed with the THP-1 cell line. In air samples, a medium cytotoxic effect (61–68% cell viability) was observed in 3 out of 15 samples. The cytokine responses produced a more potent average cell response (46.8 ± 12.3 ρg/mL IL-1β; 90.8 ± 58.5 ρg/mL TNF-α) on passive samples than air samples (25.5 ± 5.2 ρg/mL IL-1β and of 19.4 ± 5.2 ρg/mL TNF-α). A multi-approach regarding parameters to assess, sampling, and analysis methods should be followed to characterize the bioburden in the hospital indoor environment. This study supports the importance of considering exposure to complex mixtures in indoor environments.
- Exposure assessment to mycotoxins in a Portuguese fresh bread dough company by analysis of dust and urine samplesPublication . Viegas, Susana; Assunção, Ricardo; Nunes, Carla; Osteresch, Bernard; Twaruzek, Magdalena; Kosicki, Robert; Grajewski, Jan; Alvito, Paula; Almeida, Ana; Viegas, CarlaOccupational exposure to mycotoxins can occur in many and different work environments. Critical workplaces for mycotoxins appearance have already been studied and nowadays it is possible to investigate that exposure to mycotoxins is likely through inhalation due to their presence in dust. This study aimed to assess occupational co-exposure to mycotoxins in a fresh bread dough company, an workplace not studied until now.
- Exposure assessment to mycotoxins in a Portuguese fresh bread dough company by using a multi-biomarker approachPublication . Viegas, Susana; Assunção, Ricardo; Nunes, Carla; Osteresch, Bernd; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Martins, Carla; Alvito, Paula; Almeida, Ana; Viegas, CarlaMycotoxins are toxic mold metabolites that can persist in environment long after the fungi species responsible for their production disappear. Critical workplace for mycotoxins presence has already been studied and nowadays it is possible to recognize that exposure to mycotoxins through inhalation occurs due to their presence in dust. This study aimed to assess occupational co-exposure to multiple mycotoxins in a fresh bread dough company, an occupational setting not studied until now. Occupational exposure assessment to mycotoxins was done using a LC-MS/MS urinary multi-biomarker approach. Twenty-one workers and nineteen individuals that were used as controls participated in the study. Workers/controls (spot-urine) and environment (settled dust) samples were collected and analyzed. Concerning workers group, DON-GlcA, and OTA were the most prevalent biomarkers (>LOD), 66% and 90.5%, respectively. In the control group, OTA was also one of the most detected (68%) followed by CIT (58%) and DON-GlcA (58%). DON was the mycotoxin measured in high amounts in the settled dust sample (58.2 ng/g). Both workers and controls are exposed to several mycotoxins simultaneously. The workers group, due to their high contact with flour dust, revealed a higher exposure to DON. Considering these results, risk management measures must be applied including specific and adequate health surveillance programs in order to avoid exposure and consequently the associated health consequences.
- Fungal and mycotoxigenic burden from feed applied in Portuguese aquaculturePublication . Viegas, Carla; Esteves, Liliana; Faria, Tiago; Pombo, Ana; Caetano, Liliana Aranha; Gomes, Anita Quintal; Twaruzek, Magdalena; Kosicki, Robert; Grajewski, Jan; Viegas, SusanaAquaculture is one of the most important animal husbandry systems, allowing a regular growth of 1% per year in the last three decades worlwide. As in other animal production, feed safety is an essential factor to assure the productivity of those aquatic activities. The aim of this study was to assess fungal and mycotoxigenic burden in seven different feeds, four filters from aquaculture recirculation tanks and seven water samples from the same tanks.
- Fungal diversity and mycotoxin distribution in echinoderm aquaculturePublication . Viegas, Carla; Esteves, Liliana; Faria, Tiago; Pombo, Ana; Caetano, Liliana Aranha; Gomes, Anita Quintal; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Viegas, SusanaAquaculture has been a growing sector of food production worldwide in the last decades and now starts to include new, unconventional species from the Phylum Echinodermata, such as sea urchin (Paracentrotus lividus) and sea cucumber (Holothuria tubulosa). However, little is known in this context with regard to food safety aspects arising from toxigenic fungi. In this study, samples of feed (n = 7) and water (n = 8) or water filters (n = 4) from experimental aquaculture systems, producing sea urchin and sea cucumber, were analyzed by culture-based microbiological methods to assess fungal associations. Additionally, a search using molecular techniques for toxigenic sections within the genus Aspergillus in these materials was done. Finally, samples were analyzed for 37 mycotoxins by LC-MS/MS. In feed samples, Fusarium verticillioides and F. culmorum were detected. In water and water filter samples, Aureobasidium spp., Penicillium spp., and Cladosporium spp. were found. No genes of species from toxigenic Aspergillus sections were detected. Some feed samples were contaminated by multiple mycotoxins, namely deoxynivalenol (DON), zearalenone (ZEN), fumonisins (FBs), T-2 toxin, ochratoxin A (OTA), and mycophenolic acid (MPA). This is the first one study dealing with toxigenic fungi and mycotoxins in echinoderm-producing aquaculture. Although no clear evidence for adverse effects on the production systems could be found, the confirmed environmental association of mycotoxins and echinoderms requires further consideration. Studies on the consequences of introducing cereal-based fungi and their mycotoxins via feeds into aquaculture systems for echinoderm production seem to be advisable, to assess possible adverse effects on production and to clarify the potential impact on public health.
- Mechanic protection gloves used in waste sorting industry: suitable as passive method to sample for fungal burdenPublication . Viegas, Carla; Dias, Marta; Almeida, Beatriz; Gomes, Anita Q.; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Viegas, SusanaBackground: The high prevalence of airborne bacterial and fungal species in forklift cabinets from waste sorting units has already been described. Aspergillus spp. species are filamentous fungi commonly found in different environmental compartments, where they thrive as saprophytes. Several sections are reported as being mycotoxins producers. In Portuguese waste industries, personal protective equipment, such as mechanical protection gloves (MPG) are of mandatory use. During their use, sweat is released, and consequently, the material humidity and temperature inside the glove increase leading to favorable conditions for the microorganism’s growth. This study intends to assess the fungal and mycotoxins contamination present in MPG as a potential passive sampling method to assess occupational exposure.
- Multi-mycotoxin occurrence in feed: the case of one dairy farm located in PortugalPublication . Viegas, Susana; Twarużek, Magdalena; Kosicki, Robert; Grajewski, Jan; Viegas, CarlaMycotoxins presence can affect dairy farming with regards to feeding contamination and the risks posed not only to productivity but also due to the ability to reach the human diet through the consumption of animal by-products such as milk. A study aimed to characterize the multi-mycotoxin occurrence in the feed of one dairy farm located in Portugal.