A research report submitted to the Faculty of Health Sciences, School of Public Health, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Public Health: Occupational Hygiene, Johannesburg, 2012 / The aim of the study was to determine if the gold mine under study achieved the 2008 elimination of silicosis occupational hygiene milestones as set out by the South African mining industry in 2003. To identify high risk quartz exposed occupations within the conventional stope and TM³ stope employees of an underground gold mine between July 2008 and June 2010; to describe the personal quartz exposure of conventional stope and TM³ stope employees in an underground gold mine between July 2008 and June 2010; and to compare the time weighted average (TWA) quartz exposures between the conventional stope and TM³ stope to the Department of Mineral Resources-Occupational Exposure Limit (DMR-OEL) of 0.1 mg/m3, the National Institute of Occupational Safety and Health-Recommended Exposure Limit (NIOSH-REL) of 0.05 mg/m3 and the American Conference of Government Industrial Hygienists-Threshold Limit Value (ACGIHTLV) of 0.025 mg/m3.

Student Number : 0316118X - MPH research report - School of Public Health - Faculty of Health Sciences / Introduction: On the weekend of 16 – 17 December 1995, the community of Macassar was exposed to elevated levels of sulphur dioxide vapours (SO2) caused by a fire on a nearby stockpile for approximately 21.5 hours. It has been estimated that community members were exposed to levels as high as 200 parts per million (ppm) of this gas as some 15 000 tons of the sulphur stockpile ignited. This resulted in a toxic plume of SO2 being blown over the Macassar area by the prevailing wind. The aim of this study was to assess the environmental and host factors associated with persistent lower respiratory symptoms among residents of this community six years after being acutely exposed to elevated exposures of SO2 vapours. Materials and methods: A case-control study was conducted. The cases and controls were selected from adult residents who reported to the Macassar disaster project clinic for a health assessment in order to lodge a medico-legal claim. Survey instruments included a questionnaire, clinical examination and clinical record review by an expert panel. A case was defined as an adult resident who presented to the clinic for an examination with persistent (at year 1 and 6 after the disaster) lower respiratory symptoms. Controls were chosen from clinic attendees without lower respiratory symptoms at year 1 and 6. Environmental exposure was calculated by using the Industrial Source Complex Short Term Model (ISCST 3) to predict time-averaged concentrations at specified receptor locations. Multiple logistic regression was used to investigate the association between lower persistent respiratory symptoms, host and environmental factors (estimated concentration and duration of exposure to SO2). Results: A total of 76 cases and 180 controls were selected. The cases and controls were comparable with respect to age, gender, height and smoking status. The results indicated that a medical history of pulmonary tuberculosis at least one year prior to the fire (OR: 3.5, CI: 1.5-8.4) was significantly associated with having persistent lower respiratory symptoms. Furthermore, subjects with persistent lower respiratory symptoms were nine times more likely to report symptoms of tight chest (OR: 9.9; CI: 5.2-19.1), and twice as likely to report shortness of breath (OR: 2.0; CI: 1.0-4.1) at the time of the fire. None of the exposure metrics (total hours of exposure, cumulative exposure, peak exposure) were significantly associated with persistent lower respiratory symptoms. However, peak SO2 exposure estimated at hour 15 was significantly associated with persistent lower respiratory symptoms (OR: 1.0; CI: 1.0-1.1). Discussion: The results of this study are consistent with previous studies reporting lower respiratory tract symptoms after chemical exposure irrespective of age or smoking status. Furthermore, as in other studies respiratory health status was a significant factor in determining susceptibility to SO2 exposure. Various reports in the literature suggest that exposure > 20 ppm is associated with chronic respiratory symptoms. This however was not demonstrated in this study, using estimates of exposure calculated using the ISCST model suggesting possible exposure misclassification. “Self-selection” bias was an important limitation in this study, since the entire study population was self-referred and as such the study population was not randomly selected. Another limitation is the possibility that there may be potential recall bias operating since the fire incident happened six years ago; however this was considered unlikely as there was nondifferential reporting between cases and control. Self reported symptoms on the questionnaires might have been over-reported due to fear, anxiety and stress or secondary gain related to compensation issues. The lack of association between exposure variables and persistent asthma may have also been due to lack of power (small sample size), although this was thought to be a minor contributory factor. Conclusion: Host-related factors such as a previous history of pulmonary TB and acute asthma-like symptoms at the time of the fire were important predictors of persistent lower respiratory symptoms reported by residents 6 years after acute exposure to SO2 vapours emanating from a sulphur fire.

Introduction The problems associated with poor indoor air quality and the possible subsequent effects thereof on workers, as experienced by the Department of Health in the Regional office situated in the Karel Schoeman building (KSB) in Pretoria, were investigated and are discussed. The possible association between the physical indoor environmental conditions and the sick building syndrome (SBS) like symptoms as well as the seemingly low productivity and the above average rate of absenteeism are included in these discussions. To find a possible association between these poor physical environmental indoor conditions and the potential adverse affects on the health and motivation of workers, a cross sectional survey was conducted to assess the physical, biological and chemical quality of indoor air (Refer to as IAQ – Indoor Air Quality) as well as the chemical and biological quality of the drinking water. Objectives This research report documents a project to measure the environmental conditions which include CO(Carbon Monoxide), CO2(Carbon Dioxide), relative humidity( RH), temperature, air velocity, the microbial and chemical composition of the drinking water and culturable micro organisms in specific work environments within the KSB and to compare the outcome to standards for acceptable indoor working environments. The specific objectives of this study are:  To describe the environmental conditions CO, CO2, RH, temperature and air velocity exposures in specific work environments during the period 2003-2004;  To describe the microbial exposures to Legionellae (which is actually one of a group of similar diseases collectively known as Legionellosis.)  To compare measured environmental exposures to the Environmental Regulations for workplaces promulgated in terms of the Occupational Health and Safety Act 1993 (Act 85 of 1993) (OHSA), the National Institute for Occupational Safety and Health (NIOSH) standards and other national and internationally recognised standards and  To compare the microbial monitoring results including the evaluation results of the drinking water for culturable micro organisms and E.coli, to the NIOSH and other national and international recognized standards. Methods To control for confounding, samples of the drinking water as well as from a stagnant pool in the basement were taken and analysed for bacteriological and chemical compliance as well as identification of any microbes and chemicals that can contribute to SBS Environmental conditions which include CO, CO2, RH, temperature, air velocity, the microbial and chemical composition of the drinking water and culturable micro organisms including E.coli, in specific work environments were measured. Measurements were conducted in accordance with the procedures prescribed in the ASHRAE 41.6 of 1994, ACGIH (Handbook for industrial ventilation, EPA building Air quality guidelines, US Department of Labour –OHSA Technical manual),the respective manufacturers recommendations and the SABS Code 0400 of 1990 and sampling of the water in terms of the procedures prescribed by NIOH in the case of sampling for Legionellae and the Microbiological laboratory of the Rietvlei accredited water research laboratory with reference to sampling for identification of micro organisms including E.coli and the chemical composition. Appropriate recognized analytical methods were used to analyse and interpret the data generated from both the chemical and biological sampling results. Results Based on the outcome of the project results, it is clear that the air conditioning system does meet the mentioned minimum prescribed physical environmental national and international norms and standards for indoor air quality. The findings from the study indicate compliance of the physical environmental conditions to universally accepted standards and no association between those poor physical indoor environmental conditions and the sick building syndrome (SBS) like symptoms as well as the seemingly low productivity and the above average rate of absenteeism could therefore be made. The presence of coliform organisms above the norm in the air samples is however a concern. Discussion The OHSA requires employees to access the health and safety risks that hazards pose to their employees in their respective working environments and to take reasonably practicable steps towards eliminating or controlling these hazards. Like any other risks in a workplace environmental conditions need to be identified and controlled based on the principles of risk management. Conclusion The above high rate of absenteeism, as perceived by management, could not be associated with the environmental conditions covered in this project. It could however be ascribed, directly or indirectly to the following variables and assumptions which could be categorised under environmental conditions and the management thereof as well as the management of employees/workers located within the building. Environmental conditions such as substandard quality water supply, the management processes during the decommissioning of the old HVAC system and the commissioning of the replacement system, poor general housekeeping and unacceptable management principles of good quality clean working environments location of the building in the mid city centre of Pretoria and the possible contamination of indoor air by external sources bio quality could be variables contributing to the high rate of absenteeism. The seasonal occurrences of influenza and colds as well as home and external exposures could also possibly be considered as contributing factors in this regard. In addition poor general workers or people‟s management which could have resulted in low staff morale and personal motivation linked to poor supervision during a period of a very serious organizational restructuring which affected many workers could have also being considered as contributing factors to high absenteeism. Substandard ergonomics could have also played a role during this process.

O objetivo deste trabalho foi realizar a avaliação dos riscos ocupacionais ao mercúrio utilizado em odontologia, aos quais os auxiliares em saúde bucal (ASB) da rede pública de saúde do município de Araguaína, Tocantins, estão expostos. O processo odontológico do sistema de saúde no município em questão foi estudado, de modo minucioso, a partir de um levantamento do número de restaurações de amálgama de prata executadas durante o período de janeiro de 2003 a dezembro de 2007 na base de dados DATASUS. Nesse estudo, foram avaliadas as condições de armazenamento dos resíduos de amálgama nos consultórios odontológicos públicos do município analisado. Foram estudadas diferentes soluções-barreira para armazenamento dos resíduos de amálgama no que diz respeito a sua eficácia no combate à emissão de vapores de mercúrio para o ambiente. A solução contendo amoníaco foi a que apresentou melhor tempo para estocagem dos resíduos (19 dias a 37 ºC), seguida pela solução contendo fixador fotográfico (12 dias) e solução de bicarbonato de sódio (7 dias). Com base nestas informações, caracterizou-se o perfil do ASB que atua nos consultórios públicos do município de Araguaína quanto à idade, ao sexo, ao grau de exposição ao mercúrio e aos procedimentos de biossegurança executados. O estudo possibilitou elaborar um banco de dados, com relação ao manuseio e ao descarte de resíduos de amálgama, com o intuito de subsidiar políticas públicas de saúde voltadas à modificação de situações de risco as quais os profissionais estão submetidos e/ou submetem seus pacientes. Foi realizado também um programa de monitoramento biológico, utilizando como marcador a presença de mercúrio em amostras de urina (HgU), em membros da equipe odontológica da rede municipal de saúde de Araguaína e em alunos da escola técnica de saúde, polo de Araguaína, atuantes como ASB em outros municípios da região norte (n=91). Como comparação, um grupo de não expostos ao mercúrio foi avaliado (n=43) e os valores de HgU determinados. A pesquisa permitiu concluir que, em relação aos valores de HgU, a equipe odontológica avaliada estava dentro dos limites propostos pela NR 7 (até 35 gHg.g-1CR). Com relação à contaminação por mercúrio, a média da concentração do HgU para o grupo expostos (5,61 μgHg.g-1CR) foi aproximadamente 8 vezes maior se comparada ao do grupo não expostos (0,65 μgHg.g-1CR), evidenciando a necessidade de um programa de treinamento de profissionais e de gerenciamento de resíduos, bem como de uma atuação mais efetiva na realização do monitoramento biológico periódico nos profissionais da equipe odontológica. / The aim of this work was to evaluate the occupational risks of exposure to mercury utilized in dentistry, to which dental auxiliaries from the public health system of the city of Araguaína, Tocantins, Brazil are exposed. The dentistry process from the city health system was rigorously studied based on an assessment, in the DATASUS database, of the number of amalgam restorations conducted in the period from January 2003 to December 2009. In this study, we evaluated the storage conditions of mercury residuals in the public dental offices in the studied municipality. Different barrier solutions for the storage of mercury residuals were studied regarding their efficacy in controlling the emission of mercury vapor in the environment. The solution containing ammonia presented the best time of storage of residuals (19 days at 37 °C), followed by the so lution containing photographic fixative (12 days) and the sodium bicarbonate solution (7 days). Based on these information, a profile of the dental auxiliaries actuating in the public dental offices of the city of Araguaína was characterized according to age, sex, level of exposure to mercury and conducted biosecurity procedures. The study allowed the elaboration of a database regarding handling and discard of amalgam residuals, with the purpose to assist public health policies to modify risk situations to which the professionals and/or their patients are exposed. A biological monitoring program was also carried out using as marker the presence of mercury in urine samples (HgU) from members of the dentistry team of the Araguaína public health system and from students from the Araguaína unit of the health care technical school who actuated as dental auxiliaries in other municipalities of the north region of the state (n=91). For comparison, a group of not exposed to mercury was evaluated (n=43), determining their HgU values. The research allowed to conclude that the HgU values from the dentistry team were within the limits set by Regulatory Norm nº 7 by the Brazilian Ministry of Labor (up to 35 gHg.g-1CR). Regarding mercury contamination, the average HgU concentration for the exposed group (5,61 μgHg.g-1CR) was approximately 8 times higher when compared to the values from the not exposed group (0,65 μgHg.g-1CR), making evident the need for a professional training and residuals management program, as well as for a more effective actuation in the realization of periodical biological monitoring in the professionals from the dentistry team.

Introdução: A informalidade no mercado de trabalho assola muitas economias em desenvolvimento e é uma característica notável da produção de joias e bijuterias em Limeira, São Paulo, um dos maiores polos de produção de joias e bijuterias do Brasil. A produção de joias e bijuterias envolve o manuseio de produtos que podem ter em sua composição elementos com potencial tóxico à saúde humana. Em Limeira, a atividade de produção ocorre dentro dos domicílios, o que significa que o trabalhador e seus familiares podem estar expostos a elementos potencialmente tóxicos (EPT) oriundos da atividade ocupacional. Objetivos: Este estudo investigou a exposição ocupacional aos EPTs Cromo (Cr), Manganês (Mn), Níquel (Ni), Cobre (Cu), Zinco (Zn), Arsênio (As) Cádmio (Cd), Antimônio (Sb), Estanho (Sn), Mercúrio (Hg) e Chumbo (Pb), dos trabalhadores domiciliares e de seus familiares inseridos no arranjo produtivo de joias e bijuterias na cidade de Limeira - SP e discutiu os riscos identificados no ambiente de trabalho domiciliar versus a legislação ocupacional vigente. Métodos: Este estudo incluiu 52 famílias (n=165 indivíduos), divididas em grupo Exposto (n=112) e grupo Controle (n=53). Foram coletadas amostras de sangue (n=165) dos trabalhadores e seus familiares, e amostras de ar da zona de respiração de soldadores (n=9). As concentrações de EPTs foram determinadas por espectrometria de massas com plasma indutivamente acoplado (ICP-MS). Questionários foram aplicados para obter informações sociodemográficas, detalhes das condições do local de trabalho e dos materiais utilizados. As informações relevantes para compor a avaliação do ambiente de trabalho frente aos requisitos legais vigentes foram obtidas a partir destes questionários. Além disso, a análise de componentes principais (PCA), formação de clusters e regressão logística foram realizadas. Resultados: Os elementos Cd, Ni e Cu apresentaram concentração no ar maiores do que as diretrizes ocupacionais americanas. Foi encontrada diferença estatisticamente significativa para a concentração de Pb entre os grupos Exposto e Controle e entre os sexos (p <0,05), já para o Cu e Sb foram encontradas diferenças apenas entre os sexos (p <0,05). Conclusões: As concentrações de EPTs encontradas no ar são preocupantes, uma vez que os familiares dos trabalhadores, incluindo as crianças, estão no mesmo cenário de exposição. Condições inadequadas de trabalho foram observadas nas residências, revelando a necessidade de implementar ações públicas urgentes para proteger essas famílias de trabalhadores. A avaliação do cenário de exposição revelou que os trabalhadores e familiares estão sob os mesmos riscos de exposição, uma vez que a produção de joias é realizada sem nenhuma proteção do trabalhador e em ambiente geralmente compartilhado dentro das casas. Ações públicas e remodelagem do fluxo produtivo são necessárias para proteção social e de saúde destes trabalhadores e seus familiares com foco em melhoria das condições de trabalho e regularização profissional. / Introduction: Informality in the occupational segment devastated many developing economies and is a notable feature of the production of jewelry and fashion jewelry in Limeira city, São Paulo, one of the largest poles of jewelry and fashion jewelry production in Brazil. The production of jewelry and fashion jewelry involves the manipulation of chemical products that may have in their composition potentially toxic elements (PTE) to human health. In Limeira, the production activity occurs inside the households, which means that worker and family members could be exposed to PTE from the occupational activity. Objective: This study investigated occupational exposure to PTE Chromium (Cr), Manganese (Mn), Nickel (Ni), Copper (Cu), and Zinc (Zn), Arsenic (As), Cadmium (Cd), Antimony (Sb), Tin (Sn), Mercury (Hg), and Lead (Pb), household workers and their families included in the production of jewelry and fashion jewelry in Limeira, and discussed the risks identified in the households\' occupational environment assessment versus the current occupational legislation. Methods: This study included 52 families (n = 165 individuals), divided into Exposed group (n = 112) and Control group (n = 53). Blood samples (n = 165) were collected from the workers and their relatives, and air samples from the breathing zone of welders (n = 9). Concentrations of EPTs were determined by ICP-MS. Questionnaires were applied to collect sociodemographic information, details of the workplace conditions and the materials used. The relevant information to compose the occupational environment assessment against the current legal requirements were obtained from these questionnaires. In addition, the principal component analysis (PCA), clusters formation and logistic regression were performed. Results: Cd, Ni, and Cu elements presented higher air concentration than the American occupational guidelines limits. A statistically significant difference was found for the Pb concentration between the exposed and control groups and between the sexes (p <0.05), whereas for Cu and Sb only differences between the sexes were found (p <0.05). Conclusions: Concentrations of EPT found in the air raise concern, since workers\' relatives, including children, are in the same exposure scenario. Inadequate working conditions were observed in the houses, revealing the need to implement urgent public actions to protect these families and the workers. The exposure assessment revealed that workers and family members are at the same risk of exposure as the production of jewelry is carried out without any individual protection and, generally, is performed in the shared environment inside the houses. Public actions and remodeling the productive flow are necessary for the social and health protection of these workers and the families with a focus on improving working conditions and professional regularization.

Thesis advisor: Jeremy D. Shakun / Few data are available to infer the thinning rate of the Laurentide Ice Sheet (LIS) through the last deglaciation, despite its importance for constraining past ice sheet response to climate warming. We measured 31 cosmogenic 10Be exposure ages in samples collected on coastal mountainsides in Acadia National Park and from the slightly inland Pineo Ridge moraine complex, a ~100-km-long glaciomarine delta, to constrain the timing and rate of LIS thinning and subsequent retreat in coastal Maine. Samples collected along vertical transects in Acadia National Park have indistinguishable exposure ages over a 300 m range of elevation, suggesting that rapid, century-scale thinning occurred at 15.2 ± 0.7 ka, similar to the timing of abrupt thinning inferred from cosmogenic exposure ages at Mt. Katahdin in central Maine (Davis et al., 2015). This rapid ice sheet surface lowering, which likely occurred during the latter part of the cold Heinrich Stadial 1 event (19-14.6 ka), may have been due to enhanced ice-shelf melt and calving in the Gulf of Maine, perhaps related to regional oceanic warming associated with a weakened Atlantic Meridional Overturning Circulation at this time. The ice margin subsequently stabilized at the Pineo Ridge moraine complex until 14.5 ± 0.7 ka, near the onset of Bølling Interstadial warming. Our 10Be ages are substantially younger than marine radiocarbon constraints on LIS retreat in the coastal lowlands, suggesting that the deglacial marine reservoir effect in this area was ~1,200 14C years, perhaps also related to the sluggish Atlantic Meridional Overturning Circulation during Heinrich Stadial 1. / Thesis (MS) — Boston College, 2017. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.

Babyschema är ett fysionomiskt fenomen som innefattar infantila särdrag såsom stor ögon- och huvudform i kombination med liten näsa och haka. Utseendet kan ses hos digitala karaktärer i moderna spel och filmer vilket kan ha en psykologisk effekt hos betraktaren då exponering bevisats influera preferenser. Studien ämnar att utreda uppfattningen av ansikten med babyschema och om visuell exponering kan påverka dessa uppfattningar. Undersökningen utfördes på 70 testdeltagare, där ansikten med varierande grader av babyschema presenterades före och efter exponering innehållande karaktärer med babyschema eller realistiska proportioner. Resultaten indikerar att exponering för babyschema i viss utsträckning resulterar i en positiv förskjutning hos deltagarnas uppfattningar däremot hade exponering ingen positiv inverkan på deltagarnas respons till extrem babyschema. Framtida arbeten skulle kunna undersöka babyschema applicerat på manliga och kvinnliga karaktärer i en spelmiljö. I en förlängning kan studier inom ämnet syfta till att upplysa kreatörer om karaktärsdesign och dess möjliga påverkan på samhället.

O aporte artificial de nutrientes nos ambientes aquáticos tem favorecido a incidência de florações de cianobactérias, causando impactos na qualidade da água e colocando em risco a saúde humana. O gênero de cianobactéria Cylindrospermopsis, amplamente distribuído em água doce pelo mundo, é capaz de produzir diversas cianotoxinas, dentre elas saxitoxina e análogos. O objetivo deste trabalho foi elaborar um modelo de exposição referente à ingestão de água contaminada por saxitoxina e análogos através da recreação de contato primário e do consumo de água. Os dados de densidade de células de Cylindrospermopsis e de concentrações de saxitoxina e análogos na água bruta foram obtidos da Rede de Monitoramento de Qualidade de Águas Superficiais da CETESB (2015 e 2016) do reservatório Itupararanga. O modelo conceitual de exposição e o cálculo da ingestão diária crônica de saxitoxina e análogos consideraram: concentrações máxima e mínima de saxitoxina e análogos encontradas na água bruta do reservatório, vias de exposição, população exposta, taxa de ingestão de água, frequência e duração da exposição, peso corporal para adultos (maiores de 21 anos) e crianças (menores de 5 anos), para cenários de exposição relativos à recreação de contato primário e consumo de água potável. Os valores de células de cianobactérias estiveram entre 2.216 e 203.082 céls.mL-1 e as concentrações de saxitoxina e análogos estiveram entre 0,04 e 0,37 &#181;g equivalente STX..L-1. Os resultados obtidos na análise da água bruta do reservatório, estiveram abaixo do valor estabelecido na legislação brasileira para água potável (3 &#181;g equivalente STX.L-1), mas não atenderiam as especificações adotadas por Oregon e Ohio (0,3 &#181;g equivalentes STX.L-1) e à proposta em discussão no Comitê Permanente para Gestão Integrada da Qualidade da Água destinada ao Consumo Humano no Estado de São Paulo (0,13 &#181;g equivalente STX.L-1), indicando a possibilidade da ocorrência de efeito adverso à saúde em grupos sensíveis que utilizem água do reservatório, dependendo da eficiência de remoção dessas cianotoxinas no processo de tratamento. Os valores de ingestão diária crônica estimados, para recreação, variaram de 2,55 x 10-6 a 1,08 x 10-4 &#181;g equivalente STX. kg-1.dia-1 (adultos) e 2,78 x 10-9 a 4,35 x 10-4 &#181;g equivalente STX. kg-1.dia-1 (crianças). Para ingestão de água potável, esses valores variaram de 2,5 x 10-4 a 1,47 x 10-2 &#181;g equivalente STX. kg-1.dia-1 (adultos) e 5,36 x 10-5 a 2,55 x 10-2 &#181;g equivalente STX. kg-1.dia-1 (crianças). Esses valores indicaram que as crianças estão mais expostas que os adultos, fato preocupante, pois elas são mais sensíveis aos efeitos de substâncias tóxicas, e apesar de estudos indicarem efeitos da saxitoxina em cultura de células neurais, sua capacidade de atravessar a barreira hematoencefálica e de causar danos cognitivos em ratos, os efeitos da exposição crônica em humanos ainda são desconhecidos. Não foi possível estimar os riscos à saúde da população exposta à saxitoxina e análogos, pela falta de dados na literatura, porém o modelo de exposição proposto é um avanço para a identificação de lacunas para a condução da avaliação de risco à saúde humana considerando a exposição crônica. / The artificial enrichment of nutrients in aquatic environments has favored the incidence of cyanobacteria blooms, causing impacts on water quality and putting human health at risk. The genus of cyanobacteria Cylindrospermopsis, widely distributed throughout the world in freshwater environments, is able to produce cianotoxin, among them saxitoxin and its analogues. The objective of this work was to elaborate a model of exposure referring to the ingestion of water contaminated by saxitoxin and analogues through recreation of primary contact and water consumption. Cylindrospermopsis cell density and saxitoxin and analogues concentrations in surface water were obtained from the CETESB Surface Water Quality Monitoring Network for the Itupararanga reservoir in 2015 and 2016. The development of the conceptual model of exposure and the calculation of the chronic daily intake of saxitoxin and analogues, considered: maximum and minimum concentrations of saxitoxin and analogues found in the raw water of the reservoir, route of exposure, exposed population, rate of water intake, frequency and duration of exposure, body weight for adults (over 21 years) and children (under 5 years), for exposures scenarios concerning recreation of primary contact and consumption of drinking water. The values of cyanobacteria cells were between 2,216 and 203,082 cells.L-1 and the concentrations of saxitoxin and analogues were between 0.04 and 0.37 &#181;g STX equivalent. L-1. The comparison of these variables indicated a significant positive correlation between them. The results obtained in the raw water analysis of the reservoir were below the value established in Brazilian legislation for drinking water (3 &#181;g equivalent STX.L-1), but would not meet the specifications adopted by US states Oregon and Ohio (0.3 &#181;g equivalents.L-1) and the proposed value for the Standing Committee for Integrated Water Quality Management for Human Consumption in the State of São Paulo (0,13 &#181;g equivalent STX.L-1), indicating the possibility of adverse health effects in sensitive groups using water from the reservoir. Estimated chronic daily intake values, for recreation, ranged from 2.55 x 10-6 to 1.08 x 10-4 &#181;g STX equivalent. kg-1.day-1 (adults) and 2.78 x 10-9 to 4.35 x 10-4 &#181;g STX equivalent. kg-1.day-1 (children). For water intake, these values ranged from 2.5 x 10-4 to 1.47 x 10-2 &#181;g STX equivalent. kg-1 day-1 (adults) and 5.36 x 10-5 to 2.55 x 10-2 &#181;g STX equivalent. kg-1. day-1 (children). These values indicated that children are more exposed than adults, a worrying fact because they are generally more sensitive to the effects of toxic substances than adults, and although studies indicate that saxitoxin was able to cross the blood brain barrier and to cause cognitive damage in rats, as well as changes in neural cell cultures, the effects of chronic exposure in humans are still unknown. It was not possible to estimate the health risks of the population exposed to saxitoxin and the like, due to the lack of data in the literature, but the proposed exposure model is an advance for the identification of gaps for conducting the human health risk assessment considering the exposure chronic.

O objetivo deste trabalho foi realizar a avaliação dos riscos ocupacionais ao mercúrio utilizado em odontologia, aos quais os auxiliares em saúde bucal (ASB) da rede pública de saúde do município de Araguaína, Tocantins, estão expostos. O processo odontológico do sistema de saúde no município em questão foi estudado, de modo minucioso, a partir de um levantamento do número de restaurações de amálgama de prata executadas durante o período de janeiro de 2003 a dezembro de 2007 na base de dados DATASUS. Nesse estudo, foram avaliadas as condições de armazenamento dos resíduos de amálgama nos consultórios odontológicos públicos do município analisado. Foram estudadas diferentes soluções-barreira para armazenamento dos resíduos de amálgama no que diz respeito a sua eficácia no combate à emissão de vapores de mercúrio para o ambiente. A solução contendo amoníaco foi a que apresentou melhor tempo para estocagem dos resíduos (19 dias a 37 ºC), seguida pela solução contendo fixador fotográfico (12 dias) e solução de bicarbonato de sódio (7 dias). Com base nestas informações, caracterizou-se o perfil do ASB que atua nos consultórios públicos do município de Araguaína quanto à idade, ao sexo, ao grau de exposição ao mercúrio e aos procedimentos de biossegurança executados. O estudo possibilitou elaborar um banco de dados, com relação ao manuseio e ao descarte de resíduos de amálgama, com o intuito de subsidiar políticas públicas de saúde voltadas à modificação de situações de risco as quais os profissionais estão submetidos e/ou submetem seus pacientes. Foi realizado também um programa de monitoramento biológico, utilizando como marcador a presença de mercúrio em amostras de urina (HgU), em membros da equipe odontológica da rede municipal de saúde de Araguaína e em alunos da escola técnica de saúde, polo de Araguaína, atuantes como ASB em outros municípios da região norte (n=91). Como comparação, um grupo de não expostos ao mercúrio foi avaliado (n=43) e os valores de HgU determinados. A pesquisa permitiu concluir que, em relação aos valores de HgU, a equipe odontológica avaliada estava dentro dos limites propostos pela NR 7 (até 35 gHg.g-1CR). Com relação à contaminação por mercúrio, a média da concentração do HgU para o grupo expostos (5,61 &mu;gHg.g-1CR) foi aproximadamente 8 vezes maior se comparada ao do grupo não expostos (0,65 &mu;gHg.g-1CR), evidenciando a necessidade de um programa de treinamento de profissionais e de gerenciamento de resíduos, bem como de uma atuação mais efetiva na realização do monitoramento biológico periódico nos profissionais da equipe odontológica. / The aim of this work was to evaluate the occupational risks of exposure to mercury utilized in dentistry, to which dental auxiliaries from the public health system of the city of Araguaína, Tocantins, Brazil are exposed. The dentistry process from the city health system was rigorously studied based on an assessment, in the DATASUS database, of the number of amalgam restorations conducted in the period from January 2003 to December 2009. In this study, we evaluated the storage conditions of mercury residuals in the public dental offices in the studied municipality. Different barrier solutions for the storage of mercury residuals were studied regarding their efficacy in controlling the emission of mercury vapor in the environment. The solution containing ammonia presented the best time of storage of residuals (19 days at 37 °C), followed by the so lution containing photographic fixative (12 days) and the sodium bicarbonate solution (7 days). Based on these information, a profile of the dental auxiliaries actuating in the public dental offices of the city of Araguaína was characterized according to age, sex, level of exposure to mercury and conducted biosecurity procedures. The study allowed the elaboration of a database regarding handling and discard of amalgam residuals, with the purpose to assist public health policies to modify risk situations to which the professionals and/or their patients are exposed. A biological monitoring program was also carried out using as marker the presence of mercury in urine samples (HgU) from members of the dentistry team of the Araguaína public health system and from students from the Araguaína unit of the health care technical school who actuated as dental auxiliaries in other municipalities of the north region of the state (n=91). For comparison, a group of not exposed to mercury was evaluated (n=43), determining their HgU values. The research allowed to conclude that the HgU values from the dentistry team were within the limits set by Regulatory Norm nº 7 by the Brazilian Ministry of Labor (up to 35 gHg.g-1CR). Regarding mercury contamination, the average HgU concentration for the exposed group (5,61 &mu;gHg.g-1CR) was approximately 8 times higher when compared to the values from the not exposed group (0,65 &mu;gHg.g-1CR), making evident the need for a professional training and residuals management program, as well as for a more effective actuation in the realization of periodical biological monitoring in the professionals from the dentistry team.

Os estudos de metabolômica ganham importância a cada dia, por ajudarem a explicar processos biológicos em situações normais (fisiológicas) ou patológicas. Oferecem uma nova visão sobre o impacto funcional da expressão gênica, complementando os estudos de sequenciamento gênico, que negligenciam o impacto da exposição ao meio ambiente na etiologia de doenças. A metabolômica tem sido aplicada na toxicologia, mostrando que o perfil metabólico comparativo de duas situações, controle e teste, pode desempenhar um papel importante na descoberta e validação de biomarcadores, além de contribuir para o entendimento e consequente interpretação dos mecanismos de ação tóxica de xenobióticos. Este projeto de pesquisa tem por objetivo utilizar uma abordagem metabolômica para avaliar o impacto de alterações metabólicas no cérebro da prole de camundongos, ocorridas após exposição (via inalação) à fumaça decorrente da queima de maconha (Cannabis sativa). Fêmeas gestantes foram expostas a doses diárias de Cannabis sativa ou ar filtrado durante todo o período gestacional. Após o nascimento, os filhotes machos ao atingirem a idade para o desmame, considerado como fase adolescente, foram separados de suas respectivas mães e expostos à Cannabis sativa ou ar filtrado por mais 60 dias. As amostras de cérebro da prole foram submetidas a análises por cromatografia em fase gasosa acoplada a espectrometria de massas (CG-MS) numa abordagem metabolômica global (untargeted metabolomics). Os perfis metabólicos dos cérebros dos animais expostos (grupo teste) foram comparados com os obtidos na análise do grupo controle (não expostos), sendo identificados os metabólitos discriminadores candidatos. Estavam alterados os metabólitos: isoleucina, uréia, leucina, GABA, ácido succínico, ácido fumárico, serina, treonina, creatinina, ácido glutâmico, ácido acetilaspártico, glicerol -1 -fosfato, ácido ascórbico, tirosina, ácido cítrico, adenina, hipoxantina, inosina e uracila. A partir dos resultados apresentados, pode-se observar, que tanto a exposição gestacional à Cannabis sativa, quanto a exposição da prole na fase adolescente, provocam alterações metabólicas importantes. Os metabólitos significativamente alterados estão envolvidos no ciclo do ácido tricarboxílico, responsável pela respiração mitocondrial, na produção de energia, atuam na biossíntese de aminoácidos, glicólise, estresse oxidativo, podendo alterar o desenvolvimento e maturação do cérebro. Os resultados são preliminares, mas contribuem para o melhor entendimento dos mecanismos toxicológicos envolvidos na exposição crônica causada por essa droga, contribuindo para a prevenção e diagnóstico de danos no desenvolvimento fetal e adolescente. / Metabolomics studies gain importance each day because they help explain biological processes in normal (physiological) or pathological situations. They provide a new insight into the functional impact of environmental gene expression, complementing gene sequencing studies that neglect the impact of environmental exposure on the etiology of diseases. Metabolomics has been applied in toxicology, showing that the comparative metabolic profile of two situations, control and test, can play an important role in the discovery and validation of biomarkers, in addition to contributing to the understanding and interpretation of the toxic action mechanisms of xenobiotics. This research project aims to use a metabolomic approach to evaluate the impact of metabolic changes in the brain of the offspring of mice, which occurred after exposure (via inhalation) to the smoke from the burning Cannabis sativa. Pregnant females were exposed to daily doses of Cannabis sativa or filtered air throughout the gestational period. After birth, male offspring were reached adolescents weaning age were separated from their respective mothers and exposed to Cannabis sativa or to the filtrate for another 60 days. Offspring brain samples were analyzed by gas chromatography coupled to mass spectrometry (GC-MS) in a global metabolomic approach (non-target metabolomics). Metabolic profiles of the exposed animals brains (test group) were compared with those obtained in the control group (non-exposed), and the candidate discriminant metabolites were identified. The metabolites were altered: isoleucine, urea, leucine, GABA, succinic acid, fumaric acid, serine, threonine, creatine, glutamic acid, acetyl aspartic acid, glycerol-1-phosphate, ascorbic acid, tyrosine, citric acid, adenine, hypoxanthine, inosine and uracil were altered. From the results presented, it can be observed that both the gestational exposure in Cannabis sativa and the exposure of the adolescent phase exposure, induced important metabolic alterations. Significantly altered metabolites are involved in the tricarboxylic acid, which are responsible for mitochondrial respiration, in energy production, act at the amino acid biosynthesis, glycolysis, oxidative stress, which may alter the development and maturation of the brain. The results are preliminary but contribute to a better understanding of the mechanisms of toxicity and of fetal and adolescent infection.