Browsing by Issue Date, starting with "2016-06-21"
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- Air microbiology – external quality assurance programPublication . Cano, Manuela; Rosa, Nuno; Correia, Helena; Faria, Ana PaulaThe Regulation on Energy Heating and Cooling Systems in Buildings (Decreto-Lei 79/2006, April 4th) imposed efficiency rules for Heating Ventilation and Air Conditioning Systems (HVAC) in buildings, established reference concentrations for chemical and microbiological pollutants and compelled the execution of regular audits to indoor air quality in order to guarantee healthy indoor environments in existing commercial buildings with large HVAC systems. Given the significant increase in indoor air quality audits it became necessary to harmonize sampling and analysis procedures for microbiological pollutants in order to obtain comparable results. The Air and Occupational Health Unit (UASO) implemented the required procedures for accreditation of the assay “Determination of airborne culturable microorganisms” according to the International Standard ISO/IEC 17025 [1], unequivocal indicator of technical proficiency. In the absence of external quality assessment programs (EQA), a requirement of the standard, the UASO Unit in collaboration with the National Program for External Quality Assessment, organized the EQA program - Air Microbiology that consists on the bacteriological and fungal enumeration in air samples collected following the EN 13998 Standard methodology [2]. The EQA program allowed the comparability of results between participant Laboratories leading also to the harmonization of procedures, improving the traceability of measurements, result validation and improving the whole process leading to accreditation. At the end of each year the organizers of the EQA Program present the results and organize training courses in the areas identified as sensitive. The most debated topics have been the equipment calibration, estimation of uncertainty, the acceptance criteria of duplicate samples and control laboratory test conditions. The aim of this study is the assessment of the results of the EQA program - Air Microbiology (2010-2015).
- Firefighters’ occupational exposure to polycyclic aromatic hydrocarbons at Portuguese fire stationsPublication . Oliveira, M.; Slezakova, K.; Alves, M.J.; Fernandes, A.; Teixeira, J.P.; Delerue- Matos, C.; Pereira, M.C.; Morais, S.Polycyclic aromatic hydrocarbons (PAHs) are among the most relevant pollutants due to their toxic, mutagenic, and carcinogenic properties. Although scarce information exists regarding firefighters’ exposure to PAHs, there is a great gap of knowledge regarding this topic. Thus the aim of this study was to assess firefighters’ personal exposure to PAHs during regular work shifts at fire stations, with emphasis on carcinogenic compounds and potential heath risks.
- Toxicity of gold nanorods on zebrafish (Danio rerio) embryosPublication . Mesquita, B.; Fraga, S.; Simões, A.M.; Lopes, I.; Teixeira, J.P.Gold nanoparticles (NPs) are being incorporated into various consumer products and are very promising in biomedicine as diagnostic and therapeutic delivery platforms. However, concerns about their safety, environmental and health impact have risen, as they might establish harmful interactions with biological systems. In this context, it is of major importance to understand the implications of exposure to these NPs on early life stages of biota, which have been considered, in general, as the most sensitive to chemical contamination. The present study aimed to evaluate the lethal and sublethal effects that gold nanorods (GNRs) may provoke on early-life stages of the fish species Danio rerio.
- The impact of an acute exercise challenge on DNA damage: an human interventionPublication . Duarte, A.; Abreu, A.; Silva, D.; Carvalho, J.; Montanha, T.; Moreira, A.; Teixeira, J. P.; Costa, C.Even though it is commonly accepted that a regular physical activity along with a healthy diet brings positive health-related outcomes, it also seems to be related to several alterations in the human metabolism, organs, cells and deoxyribonucleic acid (DNA). Indeed, there is consistent evidence supporting that above a certain level of intensity and duration, exercise may induce an increase in the generation of reactive oxygen species (ROS). The aim of this study was to analyse the immediate impact of an acute exercise challenge on human’s DNA damage, taking into account their individual characteristics and fitness levels.
- Assessment of Indoor Environmental Quality in Elderly Care CentersPublication . Cano, Manuela; Nogueira, Susana; Alves, Marta; Papoila, Ana Luísa; Aguiar, Fátima; Rosa, Nuno; Brás, Maria Clementina; Quintas, Maria Carmo; Pinhal, Hermínia; Nogueira, Ana; Proença, Carmo; Teixeira, João P.The aim of this study was to characterize indoor environmental quality in a representative sample of Elderly Care Centers (ECC) in order to associate it with ventilation, health and comfort of elderly people. Indoor air quality (IAQ) parameters and thermal comfort were measured twice, during winter and spring/summer seasons, from 18 Elderly Care Centers (ECC) located in Lisbon, with a total of 116 rooms evaluated. Carbon dioxide and carbon monoxide were monitored during occupation periods using the Indoor Air Quality Meter (TSI, model 7545, USA). Formaldehyde was collected by active sampling on impingers, using personal pumps at an airflow of 1L/min and analyzed according to NIOSH 3500 method, using visible spectrometry (UV4, UNICAM). PM10 and PM2,5 were collected by active sampling on pre-weighted PTFE filters mounted on PM10 and PM2,5 collectors (PEM, SKC), using personal pumps operating at 2L/min, followed by gravimetric analysis for particle mass according to the method IP-10A by SKC (2004). Duplicate samples of total volatile organic compounds were collected on TENAX Tubes (Ref. 25054, Supelco) using SKC personal pumps calibrated to 0.05 L/min and analyzed after thermal desorption according to ISO 16000-part 6 using gas chromatography. Duplicate samples of viable airborne bacteria and fungi were collected using the Microbiological Air Sampler (Merck) and TSA, McK and MEA for total bacteria, Gram-negative bacteria and fungi, respectively. Whole-body thermal comfort evaluation was based on PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfied) indices, according to the ISO 7730:2005. Considering the obtained results for environmental indoor quality it is possible to conclude that thermal comfort was not reached in more than 30% of the rooms. In winter, carbon dioxide concentrations were above the reference in 20% of the rooms. PM10 and PM2,5 mean concentrations were above the reference levels in approximately 25% and 30% of the rooms, respectively. Microbiological contamination (total bacteria and fungi) was above the reference levels in more than 35% of the rooms. Indoor environmental quality should be improved by controlling contamination sources, ventilation and thermal parameters (or clothing) in order to obtain healthier environments for the elderly.
- Evaluation of isoflavone content and cytotoxic activity of two new mexican alfalfa-based foodstuffsPublication . Soto-Zarazúa, M.G.; Rodrigues, F.; Costa, C.; Pimentel, F.; Teixeira, J.P.; Bah, M.; Barreira, F.; Oliveira, M.B.P.P.Alfalfa (Medicago sativa) has been used as traditional medicine for the treatment of some diseases, being a source of phytoestrogens (mainly isoflavones), with beneficial properties for humans. Furthermore, this plant is widely consumed, either directly ingested as a fresh food or as in the form of derived foodstuffs. Therefore, the comprehensive chemical characterization and the evaluation of different types of bioactivity is of utmost importance.
- Assessment of DNA damage on a group of professional dancersPublication . Esteves, F.; Teixeira, E.; Amorim, T.; Teixeira, J.P.Despite the numerous health benefits of physical activity, it is known that the induction of oxidative stress, on the cells and tissues metabolism, is a direct consequence of this practice and may contribute for various diseases. Cellular damage induced by oxidative stress can be represented through the modifications of several macromolecules such proteins, lipids and nucleic acids. Genotoxicity evaluation is a crucial tool for studying important occupational hazards. The aim of the present study was to evaluate both DNA damage and oxidative stress in blood of a group of professional dancers before and after the season, comparing the first moment with general population.
- The fogo volcano (Cape Verde) 2014 eruption: impacts on human healthPublication . Candeias, Carla; Ávila, P. F.; Alves, C.; Silva, E. F.; Rocha, F.; Pio, C; Teixeira, J. P.Volcanic eruptions disturb directly and indirectly the ecosystems and the health of the exposed populations. Hazards include, among others, toxic volcanic ashes with diameters <10 μm (PM10). During volcanic eruptions and their immediate aftermath, increased respiratory system morbidity has been observed as well as mortality among those affected by volcanic eruptions. Unfavorable health effects could partly be prevented by timely application of safety measures.
- Wildland firefighters: DNA damage and oxidative stress assessmentPublication . Abreu, A.; Duarte, A.; Silva, S.; Morais, S.; Pereira, M.C.; Fernandes, A.; Teixeira, J.P.; Costa, S.Portugal is a high risk country for forest fires. In 2013 alone, Portugal forests accounted for more than 50% of the total burned area of Southern Europe. Portuguese firefighting is supported by a human force of 30.000 firefighters. Firefighters are often exposed to many toxic combustion products, including known carcinogens (benzene, vinyl chloride, formaldehyde, polychlorinated biphenyls, particulate matter). IARC classifies firefighting (or occupational exposure as firefighters) as possible carcinogenic to humans (Group 2b). Epidemiological studies suggest that firefighters have an elevated risk of developing cardiovascular and respiratory diseases and various types of cancer. Biomonitoring data are limited, inconsistent and inconclusive. Genotoxicity evaluation is a valuable tool for studying the most important occupational hazards allowing a reasonable epidemiological evaluation of cancer prediction. The aim of this study was to evaluate DNA damage, total and oxidative, in Portuguese wildland firefighters when compared with the general population.
- Impact of physical exercise training on DNA damage and repair: does gender play a role?Publication . Silva, Ana Inês; Soares, J.P.; Silva, A.M.; Gaivão, I.; Mota, M.P.; Matos, M.Acute physical exercise is associated with an enhanced aerobic metabolism, which can result in an increased formation of reactive oxygen species (ROS). ROS can react with DNA, causing strand breaks and modified bases, namely 8-oxoguanine, one of the most common products of oxidative DNA damage, which is repaired by 8-oxoguanine DNA glycosylase 1 (OGG1). Regular physical exercise is considered as a key component of a healthy lifestyle, and its preventive effect, at least in part, is due to oxidative stress induced adaptation, which has been related with an increase in antioxidant activity and in oxidative damage repair enzymes. Gender-related differences concerning DNA damage and DNA repair have been reported. Therefore, the main purpose of this study was to analyse the effects of 16 weeks of combined physical exercise training on DNA damage and repair, in 26 healthy Caucasian individuals, 14 males and 12 females.