Models and tools for value systems analysis in collaborative environments

Dissertation to obtain the degree of Doctor in Electrical and Computer Engineering, specialization of Collaborative Networks

Genotoxic effects in occupational exposure to formaldehyde: A study in anatomy and pathology laboratories and formaldehyde-resins production

ABSTRACT – Background: According to the Report on Carcinogens, formaldehyde ranks 25th in the overall U.S. chemical production, with more than 5 million tons produced each year. Given its economic importance and widespread use, many people are exposed to formaldehyde environmentally and/or occupationally. Presently, the International Agency for Research on Cancer classifies formaldehyde as carcinogenic to humans (Group 1), based on sufficient evidence in humans and in experimental animals. Manyfold in vitro studies clearly indicated that formaldehyde can induce genotoxic effects in proliferating cultured mammalian cells. Furthermore, some in vivo studies have found changes in epithelial cells and in peripheral blood lymphocytes related to formaldehyde exposure. Methods: A study was carried out in Portugal, using 80 workers occupationally exposed to formaldehyde vapours: 30 workers from formaldehyde and formaldehyde-based resins production factory and 50 from 10 pathology and anatomy laboratories. A control group of 85 non-exposed subjects was considered. Exposure assessment was performed by applying simultaneously two techniques of air monitoring: NIOSH Method 2541 and Photo Ionization Detection equipment with simultaneously video recording. Evaluation of genotoxic effects was performed by application of micronucleus test in exfoliated epithelial cells from buccal mucosa and peripheral blood lymphocytes. Results: Time-weighted average concentrations not exceeded the reference value (0.75 ppm) in the two occupational settings studied. Ceiling concentrations, on the other hand, were higher than reference value (0.3 ppm) in both. The frequency of micronucleus in peripheral blood lymphocytes and in epithelial cells was significantly higher in both exposed groups than in the control group (p < 0.001). Moreover, the frequency of micronucleus in peripheral blood lymphocytes was significantly higher in the laboratories group than in the factory workers (p < 0.05). A moderate positive correlation was found between duration of occupational exposure to formaldehyde (years of exposure) and micronucleus frequency in peripheral blood lymphocytes (r = 0.401; p < 0.001) and in epithelial cells (r = 0.209; p < 0.01). Conclusions: The population studied is exposed to high peak concentrations of formaldehyde with a long-term exposure. These two aspects, cumulatively, can be the cause of the observed genotoxic endpoint effects. The association of these cytogenetic effects with formaldehyde exposure gives important information to risk assessment process and may also be used to assess health risks for exposed worker

Groundwater quality, vulnerability and potential assessment in Kobo Valley development project, Ethiopia

This study deals with investigating the groundwater quality for irrigation purpose, the vulnerability of the aquifer system to pollution and also the aquifer potential for sustainable water resources development in Kobo Valley development project. The groundwater quality is evaluated up on predicting the best possible distribution of hydrogeochemicals using geostatistical method and comparing them with the water quality guidelines given for the purpose of irrigation. The hydro geochemical parameters considered are SAR, EC, TDS, Cl-, Na+, Ca++, SO4 2- and HCO3 -. The spatial variability map reveals that these parameters falls under safe, moderate and severe or increasing problems. In order to present it clearly, the aggregated Water Quality Index (WQI) map is constructed using Weighted Arithmetic Mean method. It is found that Kobo-Gerbi sub basin is suffered from bad water quality for the irrigation purpose. Waja Golesha sub-basin has moderate and Hormat Golena is the better sub basin in terms of water quality. The groundwater vulnerability assessment of the study area is made using the GOD rating system. It is found that the whole area is experiencing moderate to high risk of vulnerability and it is a good warning for proper management of the resource. The high risks of vulnerability are noticed in Hormat Golena and Waja Golesha sub basins. The aquifer potential of the study area is obtained using weighted overlay analysis and 73.3% of the total area is a good site for future water well development. The rest 26.7% of the area is not considered as a good site for spotting groundwater wells. Most of this area fall under Kobo-Gerbi sub basin.

Fungal communities in archives: assessment strategies and impact on paper conservation and human health

The main results presented in this PhD Dissertation have been published in interna-tional journals included in the Science Citation Index (SCI)

Avaliação do risco de LMEMSLT : aplicação dos métodos RULA e SI / Florentino , António de Sousa Uva

RESUMO - A frequente insuficiência de informação e até, eventualmente, a presença de elementos cientificamente pouco robustos (ou mesmo hipotéticos) no procedimento de obtenção dos resultados finais (scores) com os diversos métodos de avaliação do risco, julga-se determinar a obtenção de distintos resultados no mesmo posto de trabalho e que interessam analisar. O presente estudo foi efectuado numa empresa da indústria automóvel e pretendeu contribuir para a efectividade do processo de avaliação do risco destas lesões em meio industrial. Utilizaram-se como ponto de partida as classificações de risco em postos de trabalho onde a aplicação do método OCRA — base do projecto de norma Europeu prEN 1005-5 para a estimativa do risco de LMEMSLT (Lesões Musculoesqueléticas do Membro Superior Ligadas ao Trabalho) — identificou níveis de risco moderados e/ou elevados (score OCRA ≥ 16,5). Assim nos postos de trabalho (n = 71) registou-se em vídeo a actividade de trabalho. Analisaram-se os principais factores de risco (postura, força, repetitividade e exposição a vibrações) com uma amostragem de segundo em segundo e aplicaram-se dois métodos: 1) RULA (McAtamney; Corlett, 1993); 2) SI (Moore; Garg, 1995). Dos resultados globais da aplicação dos métodos identificam- se discrepâncias evidentes: o método SI classificou 41 postos de risco elevado e o método RULA classificou apenas 26 postos de risco. Destaque para as divergências entre os postos classificados de risco elevado como, por exemplo: de entre os 41 postos com scores de risco da aplicação do método SI apenas se encontram 12 postos classificados de risco pelo método RULA. Os resultados permitem evidenciar validades preditivas diversas para os factores de risco analisados: 1) situações de aplicação de força (SI = 0,80; RULA = 0,66); 2) presença de posturas extremas (SI = 0,68; RULA = 0,48); 3) repetitividade (SI = 0,35; RULA = 0,43). Conclui-se pela divergência de resultados dos métodos SI e RULA aplicados nos mesmos postos de trabalho que tal situação alerta para a pertinência da utilização de um filtro que permita a identificação dos factores de risco presentes em cada posto de trabalho e que, por consequência, oriente a selecção do método mais indicado ou ainda, em oposição, do método contra-indicado. Este trabalho, como um contributo para uma efectiva identificação e avaliação do risco de LMEMSLT, conduz, no limite, à necessidade de elaboração de uma «grelha» das «grelhas» e de informação mais precisa sobre os métodos e sua aplicação, permitindo, desse modo, uma mais efectiva gestão do risco destas lesões.