DSA - Apresentações orais em encontros internacionais
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- Age-related dose deposition of particulate matter in human respiratory tract: findings from a birth cross-sectional study in PortugalPublication . Madureira, Joana; Slezakova, Klara; Costa, Carla; Silva, Ana Inês; Mendes, Ana; Pereira, Maria do Carmo; Teixeira, João PauloIndoor air pollution remains a great global concern. Particulate matter (PM), namely ultrafine particles (aerodynamic diameter smaller than 0.1 μm; UFP), is considered as one of the most health-relevant air pollutant for various subpopulations, one of which is children. Knowledge on the specific dose deposition of PM may provide a critical link for better understanding of the relationship between individual exposure and the respective health effects. Mathematical models have proven to be important tools for analysing PM dose deposition in the respiratory tract providing relevant data for health risk assessment, source apportionment of human lung burdens and control strategies purposes. This work aimed to estimate the deposition dose of different PM sizes at different age categories. Inhalation dosimetry estimations were carried out using the multiple-path particle dosimetry model (MPPD, v3.04). Age specific 5-lobe model with uniform expansion was adopted in the present study
- Airborne bacteria and fungi in different indoor environments: levels and dose ratesPublication . Paciência, I.; Madureira, J.; Cavaleiro Rufo, J.; Aguiar, L.; Teixeira, João Paulo; Pinto, M.; Moreira, A.; de Oliveira Fernandes, E.The study aimed to: (i) quantify bacteria and fungi concentrations in 4 indoor environments; (ii) identify the recovered fungi; (iii) assess the impact of outdoor bacteria and fungi indoors; and (iv) estimate bacterial and fungal inhalation dose rates in children and elderly. Air samples were collected from 20 primary schools, 68 homes, 9 child day-care centres and 22 elderly care centres, with a microbiological air sampler using TSA and MEA culture media.
- Analysis and Identification of Trihalomethanes in Lisbon Indoor Swimming Pools: Distribution, Determinants and Human ExposurePublication . Silva, Z.; Rebelo, H.; Silva, M.M.; Alves, A.; Cabral, C.; Almeida, A.C.; Aguiar, F.; Oliveira, A.; Nogueira, A.; Pinhal, H.; Matos, A.; Ramos, C.D.; Pacheco, P.; Aguiar, P.; Cardoso, A.S.Water disinfection methods are used in swimming pools to ensure an effective protection of users against microbiological pathogens, being chlorination the most common disinfection method used worldwide. The use of chlorine based treatment techniques has one strong drawback, which is the generation of disinfection by-products (DBPs), potentially harmful products that have been associated with respiratory and ocular symptoms, bladder cancer and adverse reproductive effects. Amongst DBPs, the most better characterized are trihalomethanes (THMs): chloroform (CF), bromoform (BF), bromodichloromethane (BDCM), and chlorodibromomethane (DBCM). In Portugal a specific legislation to assess the quality of swimming pools is inexistent. The guideline value used to evaluate total THMs in water (TTHMsW) is the one established in the Law 306/2007 - 100 μg/L. Some other water/air parameters were assessed by Law 5/97, WHO guidelines for safe recreational water environments (2006) and Standard 62.1 (2006) from American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASRHAE). The main goal of this investigation was to study the occurrence, distribution and determinants of THMs in indoor swimming pools. This will also enable an evaluation of the exposure of users to THMs. In order to achieve this goals, the characterization of water quality in 30 Lisbon indoor swimming pools, using chorine based treatment techniques, was made during a six month period. Several parameters such as TTHMs, CF, BDCM, DBCM, BF levels in water, free residual chlorine (FrCl), pH, TW, Tair, Hu, chemical oxygen demand (COD), and other, were determined in each pool, once a month. Statistical analysis was performed using the SPSS 17.0 software. Descriptive analysis was applied to all variables. Student’s t-test, Mann-Whitney tests and Spearman’s rank correlation coefficient were also used. Large variation in TTHMs and CF water levels between the pools was obtained, being CF the THM obtained in higher concentrations, with sporadic higher values than the allowed. In air, CF level (CFair) also presented occasional higher levels. There was a clear positive linear correlation between CFW and TTHMsW (R>0.95, p<0.01), CFW and CFair (R> 0.5; p<0.05), CFW and FrCl (R>0.2; p<0.05) and, CFw and Tw (R>0.2; p<0.05). Good correlations were also obtained between other THMs: BDCM and DBCM (R>0.5, p<0.01) and BF and DBCM (R>0.6; p<0.05). The strong positive correlation obtained between CFW and TTHMsW was expected, since, usually, CFW has the higher contribution to TTHMsW. CFW is often considered as a good indicator of TTHMs concentration in water. Therefore correlations between TTHMs and CFair, FrCl, and Tw were expected and observed: TTHMsW vs CFair (R>0.5; p<0.05), TTHMsW vs FrCl (R>0.2; p<0.05) and TTHMsW vs TW (R>0.2; p<0.01). In conclusion, reasonable water and air quality was obtained in the studied Lisbon swimming pools, although some pools presented high TTHMsW, CFW and CFair. These results clearly demonstrate that THMs monitoring is particularly important and that, in a near future, this should be extended to other DBPs. Furthermore, for conscious use of swimming pools, appropriate and targeted information about safe practices should be provided to pool users.
- Analysis of cellular damage induced by silica-coated iron oxide nanoparticles on neuronal cellsPublication . Laffon, Blanca; Kiliç, G.; Fernandez Bertólez, N.; Costa, C.; Costa, S.; Teixeira, J.P.; Pásaro, E.; Valdiglesias, V.The objective of this work was to evaluate toxicity induced by silica-coated ION on a human neuronal cell line (SHSY5Y).
- Aplicabilidade da PCR em tempo real na amplificação de DNA cianobacteriano em amostras preservadas.Publication . Churro, Catarina; Pereira, Paulo; Valério, Elisabete; Vasconcelos, VitorO estudo e monitorização de florescências de cianobactérias envolve frequentemente o uso de amostras fixadas a fim de evitar a sua degradação. Com o aumento das técnicas moleculares disponiveis, a possibilidade de utilizar este recurso de DNA para explorar informação genética representa uma mais valia na investigação em cianobacterias e toxinas associadas. Neste trabalho, determinou-se a quantidade e qualidade do DNA cianobacteriano recuperado a partir de amostras ambientais e de culturas fixadas com (1) solução de Lugol, (2) formaldeído, (3) gluteraldeído e (4) solução de Transeau. A quantificação e capacidade de amplificação do DNA extraído foi avaliada por PCR em tempo real utilizando como fragmento alvo o gene rpoC1. A extração foi feita com fenol-cloróformio e a pureza do DNA foi determinada espectrofotometricamente pela razão DO260/DO280 e DO260/DO230. As amostras foram analisadas em 5 diluições seriadas de 1:10 para determinar o limite de detecção e a eficiência da reacção. A amplificação das várias diluições por PCR em tempo real foi comparada com a amplificação em PCR convencional. Nas amostras fixadas com solução de Lugol ou formaldeído, a quantidade de DNA obtido foi inferior à quantidade obtida na amostra controlo (sem fixação). Contudo obteve-se DNA de boa qualidade (DO260/DO280> 1,86 e DO260/DO230> 2,22). Na análise por PCR em tempo real o fragmento alvo foi amplificado exponencialmente, com réplicas consistentes e uma eficiência de 0,91 (r2=0,99; m=-3,55) para a solução de Lugol e eficiência de 1.02 (r2=0,98; m=-3,28) para o formaldeído. No entanto a quantificação do gene alvo nestas duas amostras foi significativamente inferior à do controlo o que indica que o gene alvo pode ser quantificado mas a sua concentração não pode ser extrapolada para concentração real da amostra não fixada. Todas as diluições das amostras referidas anteriormente foram amplificadas enquanto que por PCR convencional só se obteve produto nas três primeiras diluições, o que indica maior sensibilidade do PCR em tempo real para a amplificação de amostras fixadas. Para a fixação com a solução de Transeau e gluteraldeído obteve-se DNA de fraca qualidade (DO260/DO280 <1,6) o que influenciou a quantificação espectrofotométrica, assim como a análise do gene rpoC1 por PCR em tempo real, em que a amplificação não ocorreu correctamente e as réplicas foram inconsistentes.
- Asbestos - Portuguese panoramaPublication . Cruz Nogueira, Ana; Proença, Maria do CarmoUse of Asbestos in Portugal; INSARJ / UASO and Asbestos; National Legislation
- Assessment of indoor environmental quality in elderly care centersPublication . Cano, M.; Nogueira, S.; Alves, M.; Papoila, A.L.; Aguiar, F.; Rosa, N.; Brás, M.C.; Quintas, M.C.; Pinhal, H.; Nogueira, Ana; Proença, C.; Teixeira, J.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.
- 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.
- Assessment of occupational exposure to hexavalent chromium – recommendations from HBM4EU chromate studyPublication . Santonen, Tiina; Bocca, Beatrice; Bousoumah, Radia; Duca, Radu Corneliu; Galea, Karen S.; Godderis, Lode; Göen, Thomas; Hardy, Emilie; Iavicoli, Ivo; Janasik, Beata; Jones, Kate; Leese, Elizabeth; Leso, Veruscka; Louro, Henriqueta; Majery, Nicole; Ndaw, Sophie; Pinhal, Hermínia; Porras, Simo P.; Scheepers, Paul T.J.; Sepai, Ovnair; Silva, Maria João; van Nieuwenhuyse, An; Verdonck, Jelle; Viegas, Susana; Wasowicz, WojciechIntroduction: Hexavalent chromium (Cr(VI)) is an important occupational carcinogen. In addition to air monitoring biomonitoring is commonly applied to monitor exposure to Cr(VI). Within the EU biomonitoring initiative, HBM4EU, we explored the applicability of different biomonitoring methods in the assessment of occupational exposure to Cr(VI) in welding and surface treatment activities. Materials and Methods: A multi-center cross-sectional study was performed in Belgium, Finland, France, Italy, Poland, Portugal, the Netherlands, Luxembourg and United Kingdom. Harmonized procedures were used to collect biological and industrial hygiene samples. Contextual information was collected using questionnaires. Altogether 602 exposed workers and controls were included in the study. Exposure biomarkers studied included urinary, red blood cell (RBC) and plasma Cr, and exhaled breath condensate (EBC) Cr(VI)/Cr(III). In addition, number of effect biomarkers were studied. Results: All exposure markers showed highest exposure levels among chrome plating workers. U-Cr showed a good correlation with air Cr(VI) in bath platers and welders. Observed low correlations between different exposure biomarkers suggest that these approaches are not interchangeable but rather complementary. Conclusions: U-Cr showed its value as the first approach for the assessment of internal exposure to Cr(VI). We recommend pre- and post-shift samples for low exposure levels. RBC/P-Cr and EBC-Cr(VI)/Cr(III) provide additional information when more specific information on exposure is needed. The current exposure levels require analytical methods with high sensitivity.
- Assessment of Potential Health Risks of Portuguese Wildland Firefighters’ Occupational Exposure: Biomonitoring ApproachPublication . Esteves, Filipa; Madureira, Joana; Teixeira, João Paulo; Costa, SolangeIntroduction: Worldwide, forest fires are among the most common forms of natural disasters. In the closing years of the last century, there was an increase in the burned area in some parts of the globe, including Europe. Portugal has been particularly affected by large forest fires and mega fires, which have been occurred mainly in the central and northern regions. The proximity of firefighters to fire exposes them to high levels of toxic compounds making this occupation one of the most dangerous and leading International Agency for Research on Cancer to classified occupational firefighting activity as possibly carcinogenic to humans. Up to date, the existing studies are mainly focused on environmental monitoring, existing limited information regarding biomonitoring assessments during real scenarios of wildland fires combat. This study aims to evaluate the impact of firefighting occupational exposure at molecular and cellular levels, considering personal exposure levels. Early-effect biomarkers (e.g., micronucleus, DNA strand breaks and oxidative DNA damage) will be analyzed in order to understand the mechanisms of action through which woodsmoke may impact firefighters' health, including the risk of cancer. Methodology: This ongoing prospective longitudinal study will comprise three different stages, specifically pre-exposure, exposure, and post-exposure to fire season. Around 200 wildland northern Portuguese firefighters will be involved in this study. Characterization of the study population will be conducted via questionnaires. Firefighters' personal exposure levels will be assessed by means of metabolites in exhaled breath, using an artificial olfactory system (e-nose technology). Buccal and urine samples will be used to measure genomic instability through a micronucleus test in buccal epithelial cells and urothelial cells. DNA damage and oxidative DNA damage will be evaluated in peripheral blood lymphocytes using the comet assay. Statistical analysis will be performed to determine the relationship between personal exposure levels to toxic compounds and the early-effect biomarkers over the three different phases of the study. Expected results: The obtained results will support a more accurate and comprehensive assessment of occupational risks among wildland firefighters, crucial to prevent/reduce the associated health impacts. This work will contribute to the establishment of recommendations/good practices to improve firefighters' working conditions, allowing better definitions of policies and prevention strategies highly needed in this sector.