Genotoxicity in humans and indicator species exposed to uranium wastes

Os riscos dos resíduos provenientes da extração do urânio estão associados ao seu conteúdo em metais e radionuclídeos, o que levanta preocupações às autoridades governamentais e à população em geral. As populações humanas e outras espécies animais que vivem em zonas de exploração de urânio poderão estar expostas à radiação através de resíduos e poeiras radioactivase também através de água e alimentos contaminados. A determinação dos riscos deste tipo de contaminantes é feita, principalmente, através da análise química de amostras ambientais, dando-se menos importância à determinação de efeitos biológicos. A determinação de efeitos biológicos causados pela exposição a poluentes, tem-se revelado muito importante para uma avaliação da qualidade ambiental, de modo a providenciar indicações acerca dos efeitos negativos nos seres vivos e também para complementar a informação dada pelas análises químicas de amostras ambientais. Este facto levou ao estabelecimento de biomarcadores, que consistem em respostas biológicas adversas que são específicas de uma exposição a toxinas ambientais, para serem usadas como ferramentas de avaliação da qualidade ambiental. Neste trabalho foram analisadas respostas a nível molecular e celular, em minhocas, ratinhos do campo e humanos, a fim de determinar o risco químico e radiológico dos resíduos provenientes da mina de urânio da Cunha Baixa. Este trabalho teve também como objectivo a clarificação das respostas subjacentes à exposição a metais e radionuclídeos, a fim de permitir o desenvolvimento de potenciais novos biomarcadores moleculares. Durante este trabalho foram efectuados ensaios com minhocas, em que estas foram expostas durante 56 dias a solo contaminado proveniente da mina de urânio da Cunha Baixa, em laboratório e in situ. Durante a exposição foram analisados vários parâmetros, como o crescimento, reprodução, bioacumulação de metais e radionuclídeos, histopatologia, danos no DNA, citotoxicidade e perfil de expressão genética. Para além disso, foram amostrados ratinhos do campo na mina de urânio da Cunha Baixa e numa área de referência para determinação de danos no DNA, níveis de expressão e mutações em genes supressores de tumores e também bioacumulação de metais. Por fim, foram recolhidas amostras de sangue em voluntários saudáveis pertencentes à população da aldeia da Cunha Baixa, para determinação de danos no DNA, imunofenotipagem e quantificação de metais no sangue. Os resultados revelaram que as minhocas assim como os ratinhos do campo foram negativamente afetados pela exposição aos resíduos mineiros em todos os níveis de organização biológica aqui analisados, o que faz destes organismos bons indicadores para a determinação do risco destas áreas contaminadas, evidenciando o potencial risco da exposição a estes contaminantes. Para além disso, o estudo feito à população da Cunha Baixa revelou danos no ADN e diminuição de populações importantes de células imunitárias (nomeadamente linfócitos T e NK), o que poderá resultar da exposição aos resíduos da mina, tornando as pessoas mais susceptíveis ao desenvolvimento de processos de carcinogénese. O presente estudo contribuiu significativamente para a caracterização dos riscos da exposição a resíduos provenientes de minas de urânio abandonadas, evidenciando os seus efeitos negativos a nível molecular e celular, que potencialmente poderão causar instabilidade genómica e aumentar o risco de desenvolvimento de doenças genéticas.

Marginal Activity Access Cost (MAAC): a new indicator for sustainable Land Use/Transport (LUT) planning

The paper presents the ‘Marginal Activity Access Cost’, an accessibility indicator providing estimation in monetary terms of the impacts on mobility and on the environment of locating a single new activity in a specific zone of the urban area. In the first part of this paper, the new indicator is presented and compared to other accessibility indicators proposed in literature. In the second part, the MAAC is validated through an application to the urban area of Rome. The paper concludes with brief remarks on using the proposed accessibility indicator as index of performance for sustainable spatial planning.

Environmental indicator frameworks to design and assess environmental monitoring programs

Impact Assessment and Project Appraisal, vol. 22, n.1, March 2004, p. 47–62

Portuguese version of the Tilburg Frailty Indicator: Transcultural adaptation and psychometric validation

Artigo científico disponível actualmente em Early View (Online Version of Record published before inclusion in an issue)

Spectral Reflectance Characteristics of Kimberlite Indicator Minerals and Other Selected Mineral Grains

High chromium content in kimberlite indicator minerals such as pyrope garnet and diopside is often correlated with the presence of diamonds. In this study, kimberlite indicator minerals were examined using visible light reflectance spectroscopy to determine if chromium content can be correlated with spectral absorption features. The depth of absorption features in the visible spectral region were correlated with the molecular percentage of chromium and other first series transition metal elements obtained by electron microprobe data. In the visible part of the spectrum, chromium is evident by 3 absorption features in the pyrope reflectance spectrum; one isolated and narrow feature at the wavelength 689 nm was used to correlate with the chromium mol %. The isolation of this feature in the pyrope spectra is advantageous since it is not directly affected by other proximal absorption bands that could be caused by other transition metals. Analysis of the feature indicates that as grain volume increases the depth of the absorption feature will also increase. Clustering grain volumes into fractions yields better correlation between absorption depth and mol % chromium. Other types of garnet (almandine, grossular, spessartine) and kimberlite indicator minerals (olivine, diopside, chromite, ilmenite) were analyzed to determine if other absorption features could be used to predict the proportion of specific transition metal elements. Diopside in particular illustrates the same isolated chromium absorption feature as pyrope and may indicate mol percent but needs further study with larger sample sets.

The Feasibility of Using Vocalization Scoring as an Indicator of Poor Welfare During Cattle Slaughter

The article discusses the vocalization of cattle in six slaughter plants and the results indicate that "vocalization scoring could be used as a simple method for detecting welfare problems that need to be corrected".

Impact of pesticides on indicator and pathogenic microorganism persistence under laboratory and field conditions

On s’intéresse aux impacts des pesticides sur la microflore des plantes surtout dans le contexte des légumes contaminés par des agents pathogènes. Le but de cette étude est d'évaluer l'impact de certains pesticides sur la persistance de micro-organismes indicateurs et pathogènes. En laboratoire, la persistance d’E. coli et de Salmonella en présence de quatre pesticides (Ripcord 400EC, Copper 53W, Bioprotec CAF, Serenade MAX) a été étudiée. Les plaques de Pétrifilm et le milieu sélectif XLD sont utilisés pour énumérer les populations d’E. coli et de Salmonella. Il a été démontré que le Serenade MAX favorisait la croissance microbienne, le Bioprotec CAF et le Ripcord 400EC soutenaient la survie microbienne et le Copper 53W inhibait la croissance, à la fois d’E. coli et de Salmonella. En conditions terrain, Ripcord 400EC, Copper 53W, Bioprotec CAF ont été étudiés sur une culture de brocoli irriguée avec de l'eau expérimentalement contaminée par E. coli. Dans tous les traitements, un impact de l’irrigation a été observé sur les populations de levures et de moisissures (diminution) et les bactéries aérobies totales (augmentation). Une prévalence supérieure d’E. coli a été observée dans les parcelles traitées avec le Bioprotec CAF comparativement aux traitements au Copper 53W, ce qui est en accord avec les résultats observés lors de l'essai en laboratoire. Cependant, l'analyse statistique n'a montré aucune différence significative entre les traitements appliqués. Les effets directs des pesticides sur les micro-organismes sont confirmés dans des conditions de laboratoire mais demeurent méconnus dans les conditions expérimentales au champ.

Studies on The Ecophysiology Of Some Heterotrophic and Indicator Bacteria In The Marine Environments of Kerala

The thesis entitled "Studies on the eco-physiology of heterotrophic and indicator bacteria in the marine environments of Kerala" embodies the results of an investigation carried out by the candidate at the Central Marine Fisheries Research Institute, Cochin. It is presentedd under 4 chapters in two parts (Parts A & B) and includes 6 sections. The material for the study was collected in the Cochin backwater during April 1972 to February. 1973, March 1974 to February 1975, July 1975 to June 1976 and in the ishore area during January to October, 1978 and an account of the heterotropic and indicator bacteria are given with intensity charts and tables. Samples from all the stations contained significant quantities of heterotrophs (Part A, Section I) and faecal pollution indicators (Section II). Maximum number of heterotrophic bacteria was observed during the postmonsoon period. The total counts betwen one station and the other did not vary as much as the counts between months did. The distribution was characterised by overdispersion. During 1972-73 in all the stations except the fourth the minimum heterotrophs (Total counts) were recorded during the monsoon period. Minimum counts were observed during the premonsoon period, with an increasing trend from the premonsoon to postmonsoon seasons. Maximum counts were recorded during monsoon months during 1974-75. No significant difference was noted in the total plate count between stations, months and regions. Seasonal variations in sea water was meagre during 1975-76, whereas in sediments variations were prominent during monsoon in Station I - near the mouth of the sewage effluent of Cochin City and in postmonsoon at Station II in the Mattancherry Channel and Station III near barmouth

An assessment of potential public health risk associated with the extended survival of indicator and pathogenic bacteria in freshwater lake sediments

Microcosm studies were performed to evaluate the survival of Escherichia coli, Salmonella paratyphi and Vibrio parahaemolyticus in water and sediment collected from the freshwater region of Vembanad Lake (9 35◦N 76 25◦E) along the south west coast of India. All three test microorganisms showed significantly (p < 0.01) higher survival in sediment compared to overlying water. The survival in different sediment types with different particle size and organic carbon content revealed that sediment with small particle size and high organic carbon content could enhance their extended survival (p < 0.05). The results indicate that sediments of the Lake could act as a reservoir of pathogenic bacteria and exhibit a potential health hazard from possible resuspension and subsequent ingestion during recreational activities. Therefore, the assessment of bacterial concentration in freshwater Lake sediments used for contact and non contact recreation has of considerable significance for the proper assessment of microbial pollution of the overlying water, and for the management and protection of related health risk at specific recreational sites. Besides, assessment of the bacterial concentration in sediments can be used as a relatively stable indicator of long term mean bacterial concentration in the water column above

Increased prevalence of indicator and pathogenic bacteria in Vembanadu Lake: a function of salt water regulator, along south west coast of India

Prevalence of faecal indicator bacteria, Escherichia coli and pathogenic bacteria, Vibrio cholerae, Vibrio parahaemolyticus and Salmonella were analysed in Vembanadu lake (98350N 768250E), along south west coast of India for a period of one year from ten stations on the southern and northern sides of a salt water regulator constructed in Vembanadu Lake in order to prevent incursion of seawater during certain periods of the year. While the northern side of the lake has a connection to the sea, the southern side is enclosed when the salt water regulator is closed. The results revealed the water body is polluted with high faecal coliform bacteria with mean MPN value ranging from 1718-7706/100 ml. E. coli, V. cholerae, V. parahaemolyticus and Salmonella serotypes such as S. paratyphi A, B, C and S. newport were isolated and this is the first report on the isolation of these Salmonella serovars from this lake. E. coli showed highest percentage of incidence (85.6–86.7%) followed by Salmonella (42–57%), V. choleare (40–45%) and V. parahaemolyticus (31.5–32%). The increased prevalence of indicator and pathogenic bacteria in the enclosed southern part of Vembanadu Lake may be resulting from the altered flow patterns due to the salt water regulator.