Browsing by Author "Viegas, Susana"
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- Accessing indoor fungal contamination using conventional and molecular methods in Portuguese poultriesPublication . Viegas, Carla; Malta-Vacas, Joana; Sabino, Raquel; Viegas, Susana; Veríssimo, CristinaEpidemiological studies showed increased prevalence of respiratory symptoms and adverse changes in pulmonary function parameters in poultry workers, corroborating the increased exposure to risk factors, such as fungal load and their metabolites. This study aimed to determine the occupational exposure threat due to fungal contamination caused by the toxigenic isolates belonging to the complex of the species of Aspergillus flavus and also isolates fromAspergillus fumigatus species complex. The study was carried out in seven Portuguese poultries, using cultural and molecularmethodologies. For conventional/cultural methods, air, surfaces, and litter samples were collected by impaction method using the Millipore Air Sampler. For the molecular analysis, air samples were collected by impinger method using the Coriolis μ air sampler. After DNA extraction, samples were analyzed by real-time PCR using specific primers and probes for toxigenic strains of the Aspergillus flavus complex and for detection of isolates from Aspergillus fumigatus complex. Through conventional methods, and among the Aspergillus genus, different prevalences were detected regarding the presence of Aspergillus flavus and Aspergillus fumigatus species complexes, namely: 74.5 versus 1.0% in the air samples, 24.0 versus 16.0% in the surfaces, 0 versus 32.6% in new litter, and 9.9 versus 15.9%in used litter. Through molecular biology, we were able to detect the presence of aflatoxigenic strains in pavilions in which Aspergillus flavus did not grow in culture. Aspergillus fumigatus was only found in one indoor air sample by conventional methods. Using molecular methodologies, however, Aspergillus fumigatus complex was detected in seven indoor samples from three different poultry units. The characterization of fungal contamination caused by Aspergillus flavus and Aspergillus fumigatus raises the concern of occupational threat not only due to the detected fungal load but also because of the toxigenic potential of these species.
- Accessing occupational exposure to fungi in a cork industryPublication . Viegas, Carla; Clérigo, Anália; Faria, Tiago; Sabino, Raquel; Gomes, Anita Quintal; Viegas, SusanaDifferent forms of fungal diseases affecting the nose and paranasal sinuses are recognized, including invasive and non-invasive fungal rhinosinusitis. Penicillium glabrum complex is associated with respiratory diseases such as suberosis, a typical disease of cork industry workers. In addition, Chrysonilia sitophila has been described as causing occupational asthma, associated to prolonged exposure to high counts of spores. In this study we aimed to access fungal exposure in workers from one cork industry through the mycological analysis of their nasal exudate and the environmental fungal contamination of their surroundings as well.
- Aflatoxin B1 can also be an occupational risk factor! How biomonitoring helped to evidence thisPublication . Viegas, Susana; Almeida, Ana; Veiga, Luísa; Viegas, CarlaExposure to mycotoxins is not usually identified as a risk factor present in occupational settings. This is probably due to the inexistence of limits regarding the concentration of airborne mycotoxins, and also due to the fact that these compounds are rarely monitored in occupational environments. Aflatoxin B1 (AFB1) is the most prevalent aflatoxin and is associated with carcinogenicity, teratogenicity, genotoxicity, and immunotoxicity. Although dietary exposure to AFB1 has been extensively documented, only a small number of studies examined exposure in occupational settings. The aim of study - A study was developed aiming to know exposure to AFB1 in four occupational settings: poultry and swine production, poultry slaughterhouse, and waste management.
- Air contaminants in animal production: the poultry casePublication . Viegas, Carla; Viegas, Susana; Monteiro, Ana; Carolino, Elisabete; Sabino, Raquel; Veríssimo, C.A descriptive study was developed in order to assess air contamination caused by fungi and particles in seven poultry units. Twenty seven air samples of 25 litters were collected through impaction method. Air sampling and particle concentration measurement were performed in the pavilions’ interior and also outside premises, since this was the place regarded as reference. Simultaneously, temperature and relative humidity were also registered. Regarding fungal load in the air from the seven poultry farms, the highest value obtained was 24040 CFU/m3 and the lowest was 320 CFU/m3. Twenty eight species/genera of fungi were identified, being Scopulariopsis brevicaulis (39.0%) the most commonly isolated species and Rhizopus sp. (30.0%) the most commonly isolated genus. From the Aspergillus genus, Aspergillus flavus (74.5%) was the most frequently detected species. There was a significant correlation (r=0.487; p=0.014) between temperature and the level of fungal contamination (CFU/m3). Considering contamination caused by particles, in this study, particles with larger dimensions (PM5.0 and PM10) have higher concentrations. There was also a significant correlation between relative humidity and concentration of smaller particles namely, PM0.5 (r=0.438; p=0.025) and PM1.0 (r=0.537; p=0.005). Characterizing typical exposure levels to these contaminants in this specific occupational setting is required to allow a more detailed risk assessment analysis and to set exposure limits to protect workers’ health.
- Ambulatory oncology therapy: impact on public health and environmentPublication . Costa-Veiga, Ana; Medeiros, Bruno; Luís, Rafael; Viegas, SusanaThe increasing use of chemotherapy has impelled hospitals to reorganize their services, shifting from inpatient to outpatient care. Antineoplastic drugs are a heterogeneous group of widely used treatments for neoplastic and non-neoplastic diseases, proved to be mutagens, carcinogens, and teratogens. Chemical contamination that for a long time was concentrated in care institutions can be shifting towards homes and environment. Patients excrete these drugs and their metabolic by-products in body wastes, which can expose home caregivers and family members by skin absorption and unintentional ingestion from hand to mouth contact. An example of environmental impact is their presence in freshwater systems and the consequent contamination of the potable water supply, with a risk of human exposure. This study intends to create and validate a checklist for identification of the daily routine of the patients to define surfaces which are often touched and/or used or where potential spillage of drug-loaded urine or vomit is most likely. This information is crucial to do proposals of the most appropriate corrective measures to eliminate/reduce contamination and exposure of family members in homes of ambulatory chemotherapy patients.
- Analysis of fungal burden by conventional and molecular methods in different settings and matrices: implications for public and occupational healthPublication . Gomes, Anita Quintal; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Viegas, Susana; Viegas, CarlaFungal burden has traditionally been detected by conventional culture analysis. This method allows the identification and quantification of organisms posing high health/occupational risk and is widely used by the scientific community. The fungal burden determined by culture analysis can, in most studies, be compared with legal and scientific guidelines allowing an estimation of the degree of severity of the exposure. However, this method is limited by several factors, including incubation conditions such as the incubation time, which can be very long for some species, thus preventing a quick assessment of fungal burden. Another limiting factor is competition between species: clinically relevant species might possess lower growth rates than other non-toxic fast growing fungi thus hampering their detection. These limitations can be overcome by the use of quantitative real-time PCR (qPCR). This method, based on the amplification of genomic regions specific to certain fungal species, increases sensitivity, allowing the specific detection of a given species and removing interference by other species present in the sample. qPCR also allows the detection of dormant forms of fungi, such as spores. Thus the ideal scenario is to use these the two methods in parallel, as they complement each other to provide useful information for the assessment of exposure to fungi. We briefly describe several studies where both methods were used to detect the presence of toxigenic fungi, namely Aspergillus, particularly from the Fumigati, Flavi and Circumdati sections. These include fungal analysis from different matrices such as air, feed and coffee and within different settings, including wastewater treatment plants, slaughterhouses, feed industries, poultry and swine pavilions. The results obtained with both conventional and molecular methods are compared and discussed as well as its implications for the exposed workers' health.
- Analysis of surfaces for characterization of fungal burden: does it matter?Publication . Viegas, Carla; Faria, Tiago; Meneses, Márcia; Carolino, Elisabete; Viegas, Susana; Gomes, Anita Quintal; Sabino, RaquelObjectives: Mycological contamination of occupational environments can be a result of fungal spores’ dispersion in the air and on surfaces. Therefore, it is very important to assess it in both types of the samples. In the present study we assessed fungal contamination in the air and in the surface samples to show relevance of surfaces sampling in complementing the results obtained in the air samples. Material and Methods: In total, 42 settings were assessed by the analysis of air and surfaces samples. The settings were divided into settings with a high fungal load (7 poultry farms and 7 pig farms, 3 cork industries, 3 waste management plants, 2 wastewater treatment plants and 1 horse stable) and a low fungal load (10 hospital canteens, 8 college canteens and 1 maternity hospital). In addition to culture-based methods, molecular tools were also applied to detect fungal burden in the settings with a higher fungal load. Results: From the 218 sampling sites, 140 (64.2%) presented different species in the examined surfaces when compared with the species identified in the air. A positive association in the high fungal load settings was found between the presence of different species in the air and surfaces. Wastewater treatment plants constituted the setting with the highest number of different species between the air and surface. Conclusions: We observed that surfaces sampling and application of molecular tools showed the same efficacy of species detection in high fungal load settings, corroborating the fact that surface sampling is crucial for a correct and complete analysis of occupational scenarios.
- Antineoplastic drugs contamination of workplace surfaces in two Portuguese hospitalsPublication . Viegas, Susana; Pádua, Mário; Veiga, Ana Costa; Carolino, Elisabete; Gomes, MárioDespite the classification as known or suspected human carcinogens, by the International Agency for Research on Cancer, the antineoplastic drugs are extensively used in cancer treatment due to their specificity and efficacy. As human carcinogens, these drugs represent a serious threat to the healthcare workers involved in their preparation and administration. This work aims to contribute to better characterize the occupational exposure of healthcare professionals to antineoplastic drugs, by assessing workplace surfaces contamination of pharmacy and administration units of two Portuguese hospitals. Surface contamination was assessed by the determination of cyclophosphamide, 5-fluorouracil, and paclitaxel. These three drugs were used as surrogate markers for surfaces contamination by cytotoxic drugs. Wipe samples were taken and analyzed by HPLCDAD. From the total of 327 analyzed samples, in 121 (37%) was possible to detect and quantify at least one drug. Additionally, 28 samples (8.6 %) indicate contamination by more than one antineoplastic drug, mainly in the administration unit, in both hospitals. Considering the findings in both hospitals, specific measures should be taken, particularly those related with the promotion of good practices and safety procedures and also routine monitoring of surfaces contamination in order to guarantee the appliance of safety measures.
- Application of alkaline comet assay in human biomonitoring for genotoxicity: a study on occupational exposure to cytostaticsPublication . Ladeira, Carina; Viegas, Susana; Carolino, Elisabete; Gomes, M. C.; Brito, MiguelThe use of cytostatics drugs in anticancer therapy is increasing. Health care workers can be occupationally exposed to these drugs classified as carcinogenic, mutagenic or teratogenic. Cytostatics drugs are a heterogeneous group of chemicals widely used in the treatment of cancer, nevertheless have been proved to be also mutagens, carcinogens and teratogens. Workers may be exposed to this drug, being in the hospital settings the main focus dwelled upon the pharmacy, and nursing personnel. Alkaline comet assay is one of the most promising short-term genotoxicity assays for human risk assessment, being recommended to monitor populations chronically exposed to genotoxic agents. DNA glycosylase (OGG1) represents the main mechanism of protecting the integrity of the human DNA with respect to 8-OHdG, the most well studied biomarker of oxidative damage.
- Application of human biomonitoring programmes in occupational exposure contexts: an overviewPublication . Ladeira, Carina; Viegas, SusanaHuman biomonitoring consists, in one hand by the research and investigation of environmental hazards and, in other hand in risk estimating of developing cancer by exposure to those conditions. Since carcinogenesis is a process that takes time, the biomarkers applied to recognize abnormal biological events have been developed in molecular epidemiological studies. The biomarkers allow the quantification and identification of the progression of normal to abnormal biological conditions at a molecular level. In general, biomarkers can be classified in exposure, effect and genetic susceptibility. Genotoxicity biomarkers are a sub-type of effect biomarkers and are widely used in the assessment of genomic effects caused by exposure – environmental or occupational, being considered predictors of carcinogenesis development. Taken together, and inserted in a biomonitoring program, probably is the most growing tool available nowadays for the prevention of health effects from occupational exposure to chemicals. Ethical considerations should always be taken into consideration in the planning and implementation of the biomarkers involved.