Assessment of fungal contamination in a group of Lisbon's gymnasiums with a swimming pool

The study’s main purpose was the assessment of the environmental fungal contamination, the exploration of possible associations between related environmental variables and the study of the relationship between fungal contamination of air and surfaces. A descriptive study was developed based upon air and surfaces monitoring for fungal contamination in ten indoor gymnasiums with a swimming pool located in Lisbon’s urban area. Fifty 200 litres air samples and 120 surface swabs were collected. Surfaces samples were collected before and after cleaning and disinfection and temperature and relative humidity values were registered during the collection period. Twenty five different species of fungi were identified in the air samples, being the three most commonly isolated genera the following: Cladosporium (36.6%), Penicillium (19.0%) and Aspergillus (10.2%). Thirty-seven different species of fungi were identified in the surface samples. Fusarium sp. was the most frequent genera before (19.1%) and after (17.2%) cleaning and disinfection. There was a significant association between the numbers of visitors and the fungal contamination determined in the surface samples (p<0.05). There was no significant association (p>0.05) between the contamination encountered in the air samples and the one registered in the surface samples and between the fungal contamination and the temperature or relative humidity measured on location. The data obtained enabled the assessment of the establishment’s fungal contamination and led the authors to conclude, consequently, that physical activity, which generally promotes health, can in fact be challenged by this factor.

Air fungal contamination in two elementary schools in Lisbon, Portugal

A descriptive study was developed to monitor air fungal contamination in two elementary schools in Lisbon, Portugal. Eight air samples of 250 litres through impaction method were collected in canteen, library, classrooms and also, outside premises as reference place. Simultaneously, were also monitored environmental parameters, including temperature, and humidity through the equipment Babouc, LSI Sistems and according to the International Standard ISO 7726 - 1998. Considering both schools, sixteen different species of fungi in air were identified, being the 2 most commonly isolated Cladosporium sp. (51,1%) and Penicillium sp. (27,5%). Besides these genera Trichoderma, Aspergillus, Alternaria, Chrysonilia, Botritys, Ulocladium, Athrium, Aureobasidium, Phoma, Scedosporium e Geotrichum were also isolated. Regarding yeasts, Candida sp., Cryptococcus sp. and Rhodotorula sp. were isolated. The youngest school, as well canteens in each school, presented the worst results concerning the air fungal contamination, maybe due to the higher number of occupants. There was no significant relationship (p>0,05) between fungal contamination and temperature and humidity.

Possíveis implicações da contaminação fúngica num aviário

Introdução – Apesar de em Portugal se verificar o aumento da indústria da produção de aves para consumo humano, apenas alguns estudos incidem sobre a qualidade do ar interior e as implicações da sua degradação. Objectivos – Descrever a contaminação fúngica num aviário, analisar possíveis associações com a temperatura ambiente e a humidade relativa e o possível impacto na saúde dos consumidores e trabalhadores desta unidade. Métodos – Foi desenvolvido um estudo descritivo para avaliar a contaminação fúngica num aviário. Colheram‑se 5 amostras de ar de 100 litros através do método de compactação e 4 amostras de superfícies, utilizando a técnica da zaragatoa e um quadrado de 10 cm de lado de metal. Simultaneamente, os parâmetros ambientais – temperatura ambiente e humidade relativa – também foram medidos. Resultados – Foram identificadas vinte espécies de fungos no ar, sendo os seguintes os quatro géneros mais comummente isolados: Cladosporium (40,5%), Alternaria (10,8%), Chrysosporium e Aspergillus (6,8%). Nas superfícies, 21 espécies de fungos foram identificadas, sendo os 4 géneros mais identificados Penicillium (51,8%), Cladosporium (25,4%), Alternaria (6,1%) e Aspergillus (4,2%). Importa referir o facto de Aspergillus flavus, também isolado no ar, ser reconhecido como produtor de micotoxinas (aflatoxina) e Aspergillus fumigatus, uma das espécies isoladas no ar e superfícies, ser capaz de causar aspergilose grave ou fatal. Não se verificou relação significativa (p> 0,05) entre a contaminação fúngica e as variáveis ambientais. Conclusão – Caracterizou‑se a distribuição fúngica no ar e superfícies do aviário e analisou‑se a possível influência das variáveis ambientais. Foi reconhecido um potencial problema de Saúde Pública devido à contaminação fúngica e à possível produção de micotoxinas com a eventual contaminação dos produtos alimentares. A contaminação fúngica, particularmente causada pelo Aspergillus fumigatus, e a possível presença de micotoxinas no ar, devem ser encaradas também como fatores de risco neste contexto ocupacional. ABSTRACT - Background – Although there is an increasingly industry that produce whole chickens for domestic consumption in Portugal, only few investigations have reported on the indoor air of these plants and the consequences of their degradation. Objectives – Describe one poultry environmental fungal contamination analyse possible associations between temperature and relative humidity and its possible impact on the health of consumers and of the poultry workers. Methods – A descriptive study was developed to monitor one poultry fungal contamination. Five air samples of 100 litres through impaction method were collected and 4 swab samples from surfaces were also collected using a 10 cm square of metal. Simultaneously, environmental parameters – temperature and relative humidity – were also measured. Results – Twenty species of fungi in air were identified, being the 4 most commonly isolated the following genera: Cladosporium (40.5%), Alternaria (10.8%), Chrysosporium and Aspergillus (6.8%). In surfaces, 21 species of fungi were identified, being the 4 genera more identified Penicillium (51.8%), Cladosporium (25.4%), Alternaria (6.1%) and Aspergillus (4.2%). In addition, Aspergillus flavus also isolated in the poultry air is a well‑known producer of potent mycotoxins (aflatoxin), and Aspergillus fumigatus, one of the species isolated in air and surfaces, is capable of causing severe or fatal aspergillosis. There was no significant relationship (p>0,05) between fungal contamination and environmental variables. Conclusions – Was characterized fungal distribution in poultry air and surfaces and analyzed the association of environmental variables. It was recognized the Public Health problem because of fungal contamination and also due to probable mycotoxins production with the possible contamination of food products. Fungal contamination, particularly due to the presence of Aspergillus fumigatus and also the possible presence of mycotoxins in the air, should be seen as risk factor in this occupational setting.

Comparison of fungal contamination between hospitals and companies food units

A descriptive study was developed to compare air and surfaces fungal contamination in ten hospitals’ food units and two food units from companies. Fifty air samples of 250 litres through impaction method were collected from hospitals’ food units and 41 swab samples from surfaces were also collected, using a 10 by 10 cm square stencil. Regarding the two companies, ten air samples and eight surface samples were collected. Air and surface samples were collected in food storage facilities, kitchen, food plating and canteen. Outdoor air was also collected since this is the place regarded as a reference. Simultaneously, temperature, relative humidity and meal numbers were registered. Concerning air from hospitals’ food units, 32 fungal species were identified, being the two most commonly isolated genera Penicillium sp.

Air fungal contamination in ten hospitals’ food units from Lisbon

A descriptive study was developed to monitor air fungal contamination in ten food units from hospitals. Fifty air samples of 250 litres were collected through impaction method. Samples were collected in food storage facilities, kitchen, food plating, canteen and also, outside premises, since this is the place regarded as reference. Simultaneously, environmental parameters were also monitored, including temperature and relative humidity through the equipment Babouc, LSI Sistems and according to the International Standard ISO 7726.

Sensor element for a metal-insulator-semiconductor camera system (MISCam)

We discuss the operation of a new type of optical sensor (MISCam) based on a metal-insulator-semiconductor (MIS) structure. The operation principle relies on light-induced changes of the band bending and barrier height at the interface between semiconductor and insulator. An image is obtained from the quenching of the ac signal in analogy to the principle of the laser-scanned photodiode (LSP). Lateral resolution depends on the semiconductor material chosen. We have characterised the MIS structures by C-V, I-V, and spectral response measurements testing different types of insulators like a-Si3N4, SiO2, and AlN. The presence of slow interface charges allows for image memory. Colour sensors can be realised by controlling sign and magnitude of the electric fields in the base and the interface region.

Fungal contamination of poultries litter: a public health problem

Exposure to certain fungi can cause human illness. Fungi cause adverse human health effects through three specific mechanisms: generation of a harmful immune response (e.g., allergy or hypersensitivity pneumonitis); direct infection by the fungal organism; by toxic-irritant effects from mold byproducts, such as mycotoxins. In Portugal there is an increasingly industry of large facilities that produce whole chickens for domestic consumption and only few investigations have reported on fungal contamination of the poultry litter. The material used for poultry litter is varied but normally can be constitute by: pine shavings; sawdust of eucalyptus; other types of wood; peanut; coffee; sugar cane; straw; hay; grass; paper processed. Litter is one of the most contributive factors to fungal contamination in poultries. Spreading litter is one of the tasks that normally involve higher exposure of the poultry workers to dust, fungi and their metabolites, such as VOC’s and mycotoxins. After being used and removed from poultries, litter is ploughed into agricultural soils, being this practice potentially dangerous for the soil environment, as well for both humans and animals. The goal of this study was to characterize litter’s fungal contamination and also to report the incidence of keratinophilic and toxigenic fungi.

Coexistence of Universal and Topological Anomalous Hall Effects in Metal CrO2 Thin Films in the Dirty Limit

The scaling exponent of 1.6 between anomalous Hall and longitudinal conductivity, characteristic of the universal Hall mechanism in dirty-metal ferromagnets, emerges from a series of CrO2 films as we systematically increase structural disorder. Magnetic disorder in CrO2 increases with temperature and this drives a separate topological Hall mechanism. We find that these terms are controlled discretely by structural and magnetic defect populations, and their coexistence leads to apparent divergence from exponent 1.6, suggesting that the universal term is more prevalent than previously realized.

Fungal contamination of poultry litter: a public health problem

Although numerous studies have been conducted on microbial contaminants associated with various stages related to poultry and meat products processing, only a few reported on fungal contamination of poultry litter. The goals of this study were to (1) characterize litter fungal contamination and (2) report the incidence of keratinophilic and toxigenic fungi presence. Seven fresh and 14 aged litter samples were collected from 7 poultry farms. In addition, 27 air samples of 25 litters were also collected through impaction method, and after laboratory processing and incubation of collected samples, quantitative colony-forming units (CFU/m3) and qualitative results were obtained. Twelve different fungal species were detected in fresh litter and Penicillium was the most frequent genus found (59.9%), followed by Alternaria (17.8%), Cladosporium (7.1%), and Aspergillus (5.7%). With respect to aged litter, 19 different fungal species were detected, with Penicillium sp. the most frequently isolated (42.3%), followed by Scopulariopsis sp. (38.3%), Trichosporon sp. (8.8%), and Aspergillus sp. (5.5%). A significant positive correlation was found between litter fungal contamination (CFU/g) and air fungal contamination (CFU/m3). Litter fungal quantification and species identification have important implications in the evaluation of potential adverse health risks to exposed workers and animals. Spreading of poultry litter in agricultural fields is a potential public health concern, since keratinophilic (Scopulariopsis and Fusarium genus) as well as toxigenic fungi (Aspergillus, Fusarium, and Penicillium genus) were isolated.

Chromatographic behaviour of monoclonal antibodies against wild-type amidase from Pseudomonasaeruginosa on immobilized metal chelates

The aim of this work was to devise a one-step purification procedure for monoclonal antibodies (MAbs) of IgG class by immobilized metal affinity chromatography (IMAC). Therefore, several stationary phases were prepared containing immobilized metal chelates in order to study the chromatographic behaviour of MAbs against wild-type amidase from Pseudomonas aeruginosa. Such MAbs adsorbed to Cu(II), Ni(II), Zn(II) and Co(II)-IDA agarose columns. The increase in ligand concentration and the use of longer spacer arms and higher pH values resulted in higher adsorption of MAbs into immobilized metal chelates. The dynamic binding capacity and the maximum binding capacity were 1.33 +/- 0.015 and 3.214 +/- 0.021 mg IgG/mL of sedimented commercial matrix, respectively. A K(D) of 4.53 x 10(-7) M was obtained from batch isotherm measurements. The combination of tailor-made stationary phases of IMAC and the correct selection of adsorption conditions permitted a one-step purification procedure to be devised for MAbs of IgG class. Culture supernatants containing MAbs were purified by IMAC on commercial-Zn(II) and EPI-30-IDA-Zn(II) Sepharose 6B columns and by affinity chromatography on Protein A-Sepharose CL-4B. This MAb preparation revealed on SDS-PAGE two protein bands with M(r) of 50 and 22 kDa corresponding to the heavy and light chains, respectively. Copyright (C) 2011 John Wiley & Sons, Ltd.

Fungal contamination in swine: a potential occupational health threat

Poor air quality in a pig-confinement building may potentially place farmers at higher health risk than other workers for exposure to airborne pollutants that may reach infectious levels. The aim of this study was to assess worker exposure to fungi in indoor environments in Portuguese swine buildings. Air samples from 7 swine farms were collected at a flow rate of 140 L/min, at 1 m height, onto malt extract agar supplemented with chloramphenicol (MEA). Surfaces samples of the same indoor sites were obtained by swabbing the surfaces. Samples from the floor covering were also collected from four of seven swine farms. All collected samples were incubated at 27°C for 5-7 days. After lab processing and incubation of obtained samples, quantitative colony-forming units (CFU)/m(3), CFU/cm(2), and CFU/g and qualitative results were determined with identification of isolated fungal species. Aspergillus versicolor was the most frequent species found in air (21%), followed by Scopulariopsis brevicaulis (17%) and Penicillium sp. (14%). Aspergillus versicolor was also the most frequent species noted on surfaces (26.6%), followed by Cladosporium sp. (22.4%) and Scopulariopsis brevicaulis (17.5%). Chrysosporium was the most frequently found genera in the new floor covering (38.5%), while Mucor was the most prevalent genera (25.1%) in used floor covering. Our findings corroborate a potential occupational health threat due to fungi exposure and suggest the need for a preventive strategy.

Effects of fungal contamination on respiratory symptoms of poultry workers

Exposure to certain fungi (molds) can cause human illness by 3 specific mechanisms: generation of a harmful immune response, direct infection by the organism or/and toxic-irritant effects from mold byproducts. Moulds are considered central elements in daily exposure of poultry workers and can be the cause of an increased risk of occupational respiratory diseases, like allergic and non-allergic rhinitis and asthma.

Fungal contamination: comparation between Portuguese poultries and swines

Animal confinement tends to increase the overall microbial load in the production environment caused by high amounts of feed and organic residuals (manure and wastewater) present in those environments. The number of animais and the handling and management required to work in these settings also contribute to enhance that microbial ioad. Animal housing typically exposes workers to substantial concentrations of bioaerosols, such as fungi and their metabolites. Therefore, agricultural workers, and especially pig and poultry farmers, are at increased risk of occupational respiratory diseases. Exposure to bioaerosols in poultries and swines may vary depending upon the stage of the animals' growth, density, manure management procedures, litter type and used floor coverage, among others. Gathering temporal information about the quantity and the composition of fungal load is necessary to better understand the relationship between these factors and adverse health symptoms of workers. This study aimed to characterize and compare fungal contamination between these two different settings.

Effects of fungal contamination on respiratory symptoms of poultry workers

Moulds are considered central elements in daily exposure of poultry workers and can be the cause of an increased risk of occupational respiratory diseases, like allergic and non-allergic rhinitis and asthma. The objective is to evaluate the exposure to different species of moulds in poultries and relate them with respiratory symptoms in poultry workers. Seven Portuguese poultries were analyzed in order to assess air fungal contamination, as well as to evaluate the existence of clinical symptoms associated with asthma and other allergy diseases by European Community Respiratory Health Survey questionnaire.

Occupational exposure to Aflatoxin B1 in swine production and possible contamination sources

Although the adverse health consequences of ingestion of food contaminated with aflatoxin B1 (AFB1) are known, relatively few studies are available on the adverse effects of exposure in occupational settings. Taking this into consideration, our study was developed aiming to elucidate the possible effects of occupational exposure to AFB1 in Portuguese swine production facilities using a specific biomarker to assess exposure to AFB1. In total, 28 workers participated in this study, providing blood samples, and a control group (n  = 30) was composed of subjects without any type of agricultural activity. Fungal contamination was also studied by conventional methods through air, surfaces, and new and used floor coverage. Twenty-one workers (75%) showed detectable levels of AFB1 with values ranging from <1 ng/ml to 8.94 ng/ml and with a mean value of 1.91 ± 1.68 ng/ml. In the control group, the AFB1 values were all below 1 ng/ml. Twelve different Aspergillus species were identified. Aspergillus versicolor presented the highest airborne spore counts (3210 CFU/m3) and was also detected in higher values in surfaces (>300 CFU/cm2). Data indicate that exposure to AFB1 occurs in swine barns, and this site serves as a contamination source in an occupational setting.