RESUMO
Excessive exposure to manganese (Mn) is linked to its accumulation in the brain and adverse neurological effects. Paramagnetic properties of Mn allow the use of magnetic resonance imaging (MRI) techniques to identify it in biological tissues. A critical review was conducted to evaluate whether MRI techniques could be used as a diagnostic tool to detect brain Mn accumulation as a quantitative biomarker of inhaled exposure. A comprehensive search was conducted in MEDLINE, EMBASE, and PubMed to identify potentially relevant studies published prior to 9 May 2022. Two reviewers independently screened identified references using a two-stage process. Of the 6452 unique references identified, 36 articles were retained for data abstraction. Eligible studies used T1-weighted MRI techniques and reported direct or indirect T1 measures to characterize Mn accumulation in the brain. Findings demonstrate that, in subjects exposed to high levels of Mn, deposition in the brain is widespread, accumulating both within and outside the basal ganglia. Available evidence indicates that T1 MRI techniques can be used to distinguish Mn-exposed individuals from unexposed. Additionally, T1 MRI may be useful for semi-quantitative evaluation of inhaled Mn exposure, particularly when interpreted along with other exposure indices. T1 MRI measures appear to have a nonlinear relationship to Mn exposure duration, with R1 signal only increasing after critical thresholds. The strength of the association varied depending on the regions of interest imaged and the method of exposure measurement. Overall, available evidence suggests potential for future clinical and risk assessment applications of MRI as a diagnostic tool.
Assuntos
Imageamento por Ressonância Magnética , Manganês , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , BiomarcadoresRESUMO
In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.
Assuntos
Neoplasias Encefálicas , Telefone Celular , Glioma , Adolescente , Adulto , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/etiologia , Estudos de Casos e Controles , Criança , Campos Eletromagnéticos/efeitos adversos , Glioma/etiologia , Humanos , Masculino , Ondas de Rádio/efeitos adversos , Adulto JovemRESUMO
Biomonitoring equivalents (BEs) have been increasingly applied for biomonitoring purposes by regulatory bodies worldwide. The present report describes the development of a BE for titanium based on a 4-step process: (i) identification of a critical study/point of departure (PoD) supporting an established oral exposure guidance value (OEGV);, (ii) review the available oral PK data and application of a pharmacokinetic model for titanium; (iii) selection of the most appropriate biomarker of exposure in a specific tissue and calculation of steady-state tissue levels corresponding to the PoD in the critical study; and (iv) derivation of BE value adjusting for the uncertainties considered in the original OEGV assessment. Using the above 4-step approach, a blood BE value of 32.5 µg titanium/L was derived. Key components of the analysis included a pharmacokinetic model developed by investigators at the Netherlands National Institute of Public Health (RIVM) and a two-year rodent bioassay of titanium conducted by the US National Cancer Institute. The most sensitive pharmacokinetic parameter involved in the current BE derivation is the oral absorption factor of 0.02%. The provisional BE proposed in this article may be updated as new information on the pharmacokinetics of titanium becomes available.
Assuntos
Monitoramento Biológico , Titânio/sangue , Titânio/farmacocinética , Biomarcadores/sangue , Biomarcadores/metabolismo , Humanos , National Cancer Institute (U.S.) , Países Baixos , Medição de Risco , Estados UnidosRESUMO
INTRODUCTION: Lithium salts have numerous industrial uses and are also used in the treatment of bipolar disorders. The main source of lithium exposure to the general population is drinking water and foods. Lithium is nephrotoxic at higher doses. Thus, oral exposure guidelines for lithium have been derived, including ICH's permitted daily exposure (PDE = 0.008 mg lithium/kg-bw/day) adopted by Health Canada and the United States Environmental Protection Agency's (U.S. EPA) provisional peer reviewed toxicity value (PPRTV = 0.002 mg lithium/kg-bw/day), both based on human data. OBJECTIVE: To derive whole blood biomonitoring equivalents (BEs) associated with PDE and PPRTV to interpret population-level biomonitoring data in health risk context. METHOD: A simple kinetic relationship based on plasma clearance value (0.5 L/kg-bw/day) and the oral absorption fraction (100%) was used to derive blood BEs for PDE and PPRTV. RESULTS: This analysis resulted in BE values in plasma and whole blood of 16 and 10 µg/L, respectively, based on the PDE values developed by the Health Canada and of 4.2 and 2.7 µg/L, respectively, based on the PPRTV developed by U.S. EPA. CONCLUSION: The derived BE values can be used to interpret population-level biomonitoring data.
Assuntos
Monitoramento Biológico , Exposição Ambiental/análise , Monitoramento Ambiental , Poluentes Ambientais/sangue , Lítio/sangue , Canadá , Humanos , Medição de Risco , Estados UnidosRESUMO
Advances in the biological sciences have led to an ongoing paradigm shift in toxicity testing based on expanded application of high-throughput in vitro screening and in silico methods to assess potential health risks of environmental agents. This review examines progress on the vision for toxicity testing elaborated by the US National Research Council (NRC) during the decade that has passed since the 2007 NRC report on Toxicity Testing in the 21st Century (TT21C). Concomitant advances in exposure assessment, including computational approaches and high-throughput exposomics, are also documented. A vision for the next generation of risk science, incorporating risk assessment methodologies suitable for the analysis of new toxicological and exposure data, resulting in human exposure guidelines is described. Case study prototypes indicating how these new approaches to toxicity testing, exposure measurement, and risk assessment are beginning to be applied in practice are presented. Overall, progress on the 20-year transition plan laid out by the US NRC in 2007 has been substantial. Importantly, government agencies within the United States and internationally are beginning to incorporate the new approach methodologies envisaged in the original TT21C vision into regulatory practice. Future perspectives on the continued evolution of toxicity testing to strengthen regulatory risk assessment are provided.
Assuntos
Rotas de Resultados Adversos , Medição de Risco/métodos , Testes de Toxicidade/métodos , Animais , Carcinógenos/química , Carcinógenos/toxicidade , Biologia Computacional/métodos , Mineração de Dados , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Ensaios de Triagem em Larga Escala , Humanos , National Academy of Sciences, U.S. , Relação Estrutura-Atividade , Testes de Toxicidade/tendências , Toxicogenética/métodos , Toxicologia/métodos , Estados UnidosRESUMO
We undertook a re-analysis of the Canadian data from the 13-country case-control Interphone Study (2001-2004), in which researchers evaluated the associations of mobile phone use with the risks of brain, acoustic neuroma, and parotid gland tumors. In the main publication of the multinational Interphone Study, investigators concluded that biases and errors prevented a causal interpretation. We applied a probabilistic multiple-bias model to address possible biases simultaneously, using validation data from billing records and nonparticipant questionnaires as information on recall error and selective participation. In our modeling, we sought to adjust for these sources of uncertainty and to facilitate interpretation. For glioma, when comparing those in the highest quartile of use (>558 lifetime hours) to those who were not regular users, the odds ratio was 2.0 (95% confidence interval: 1.2, 3.4). After adjustment for selection and recall biases, the odds ratio was 2.2 (95% limits: 1.3, 4.1). There was little evidence of an increase in the risk of meningioma, acoustic neuroma, or parotid gland tumors in relation to mobile phone use. Adjustments for selection and recall biases did not materially affect interpretation in our results from Canadian data.
Assuntos
Neoplasias Encefálicas/etiologia , Telefone Celular , Glioma/etiologia , Meningioma/etiologia , Neuroma Acústico/etiologia , Neoplasias Parotídeas/etiologia , Adulto , Viés , Neoplasias Encefálicas/epidemiologia , Canadá , Estudos de Casos e Controles , Campos Eletromagnéticos/efeitos adversos , Feminino , Glioma/epidemiologia , Humanos , Modelos Logísticos , Masculino , Neoplasias Meníngeas/epidemiologia , Neoplasias Meníngeas/etiologia , Pessoa de Meia-Idade , Neuroma Acústico/epidemiologia , Neoplasias Parotídeas/epidemiologia , Fatores de RiscoRESUMO
Neurological conditions are among the leading causes of disability in the Canadian population and are associated with a large public health burden. An increase in life expectancy and a declining birth rate has resulted in an aging Canadian population, and the proportion of age-adjusted mortality due to non-communicable diseases has been steadily increasing. These conditions are frequently associated with chronic disability and an increasing burden of care for patients, their families and caregivers. The National Population Health Study of Neurological Conditions (NPHSNC) aims to improve knowledge about neurological conditions and their impacts on individuals, their families, caregivers and health care system. The Systematic Review of Determinants of Neurological Conditions, a specific objective within the NPHSNC, is a compendium of systematic reviews on risk factors affecting onset and progression of the following 14 priority neurological conditions: Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), brain tumours (BT), cerebral palsy (CP), dystonia, epilepsy, Huntington's disease (HD), hydrocephalus, multiple sclerosis (MS), muscular dystrophies (MD), neurotrauma, Parkinson's disease (PD), spina bifida (SB), and Tourette's syndrome (TS). The burden of neurological disease is expected to increase as the population ages, and this trend is presented in greater detail for Alzheimer's and Parkinson's disease because the incidence of these two common neurological diseases increases significantly with age over 65 years. This article provides an overview of burden of neurological diseases in Canada to set the stage for the in-depth systematic reviews of the 14 priority neurological conditions presented in subsequent articles in this issue.
Assuntos
Doenças do Sistema Nervoso/economia , Doenças do Sistema Nervoso/epidemiologia , Saúde Pública/economia , Canadá/epidemiologia , Feminino , Humanos , Masculino , Organização Mundial da Saúde/economiaRESUMO
The application of a recently developed mathematical model for predicting the spread of chronic wasting disease (CWD) in wild deer was assessed under different scenarios where harvesting is employed in disease management. A process-based mathematical model for CWD transmission in wild deer populations was recently developed and parameterized by Al-arydah et al. (2011) to provide a scientific basis for understanding the factors that affect spread of CWD and evaluate concomitant disease-control strategies. The impact of gender on CWD transmission was shown to have a significant influence on the spread of the disease in the wild. Our model demonstrates a range of harvesting rates in which CWD is controlled and deer populations survive. However, if harvesting rates are too low, the disease remains endemic for decades. Conversely, the Canadian deer population is eradicated if harvesting rates are excessive. Future investigation includes building the model to assess the spread of CWD under different disease-management scenarios.
Assuntos
Conservação dos Recursos Naturais , Cervos , Modelos Teóricos , Doença de Emaciação Crônica/epidemiologia , Animais , Canadá/epidemiologia , Doença de Emaciação Crônica/prevenção & controle , Doença de Emaciação Crônica/transmissãoRESUMO
Occupational exposure limits (OELs) serve as health-based benchmarks against which measured or estimated workplace exposures can be compared. In the years since the introduction of OELs to public health practice, both developed and developing countries have established processes for deriving, setting, and using OELs to protect workers exposed to hazardous chemicals. These processes vary widely, however, and have thus resulted in a confusing international landscape for identifying and applying such limits in workplaces. The occupational hygienist will encounter significant overlap in coverage among organizations for many chemicals, while other important chemicals have OELs developed by few, if any, organizations. Where multiple organizations have published an OEL, the derived value often varies considerably-reflecting differences in both risk policy and risk assessment methodology as well as access to available pertinent data. This article explores the underlying reasons for variability in OELs, and recommends the harmonization of risk-based methods used by OEL-deriving organizations. A framework is also proposed for the identification and systematic evaluation of OEL resources, which occupational hygienists can use to support risk characterization and risk management decisions in situations where multiple potentially relevant OELs exist.
Assuntos
Exposição Ocupacional/normas , Medição de Risco/métodos , Níveis Máximos Permitidos , Substâncias Perigosas/toxicidade , Humanos , Cooperação Internacional , Exposição Ocupacional/prevenção & controle , Saúde Ocupacional , Gestão de RiscosRESUMO
INTRODUCTION: Metabolic syndrome (MetS) is a combination of risk markers that appear to promote the development of chronic disease. We examined the burden of MetS in Canada through its current and projected association with chronic disease. METHODS: We used measures from the Canadian Health Measures Survey 2007-2009 to identify the prevalence of MetS in Canadian adults and examine associations between sociodemographic factors and major chronic diseases. We estimated the projected cumulative incidence of diabetes and percent risk of a fatal cardiovascular event using the Diabetes Population Risk Tool (DPoRT) and Framingham algorithms. RESULTS: After adjusting for age, we found that 14.9% of Canadian adults had MetS. Rates were similar in both sexes, but higher in those who are non-Caucasian or overweight or obese (p < .001 for all three). The importance of MetS for public health was demonstrated by its significant association with chronic disease relative to the general population, particularly for diagnosed (11.2% vs. 3.4%) and undiagnosed (6.0% vs. 1.1%) type 2 diabetes. The ten-year incidence estimate for diabetes and mean percent risk of a fatal cardiovascular disease (CVD) event were higher in those with MetS compared to those without (18.0% vs. 7.1% for diabetes, and 4.1% vs. 0.8% for CVD). CONCLUSION: MetS is prevalent in Canadian adults and a high proportion of individuals with MetS have diagnosed or undiagnosed chronic conditions. Projection estimates for the incidence of chronic disease associated with MetS demonstrate higher rates in individuals with this condition. Thus, MetS may be a relevant risk factor in the development of chronic disease.
TITRE: Syndrome métabolique et maladies chroniques. INTRODUCTION: Le syndrome métabolique (SMét) est un ensemble de marqueurs de risques qui semble favoriser l'apparition de maladies chroniques. Nous avons examiné le fardeau lié au SMét au Canada et son association actuelle et projetée avec les maladies chroniques. MÉTHODOLOGIE: Nous avons utilisé les données de l'Enquête canadienne sur les mesures de la santé 2007-2009 pour déterminer la prévalence du SMét chez les adultes canadiens et pour examiner les associations entre divers facteurs sociodémographiques et les principales maladies chroniques. Nous avons estimé l'incidence cumulative projetée du diabète et le risque, en pourcentage, d'événements cardiovasculaires mortels en utilisant l'algorithme DPoRT (Diabetes Population Risk Tool) et l'algorithme de Framingham. RÉSULTATS: Après ajustement en fonction de l'âge, nous avons pu déterminer que 14,9 % des adultes canadiens présentaient un SMét. Les taux étaient similaires pour les deux sexes, mais ils étaient plus élevés chez les non-Blancs et chez les personnes présentant un embonpoint ou obèses (p < 0,001 dans les trois cas). L'importance du SMét sur le plan de la santé publique découle du fait qu'il est associé de manière statistiquement significative avec des maladies chroniques, en particulier avec le diabète de type 2 diagnostiqué (11,2 % contre 3,4 %) et non diagnostiqué (6,0 % contre 1,1 %). Le taux estimé d'incidence sur 10 ans associé au diabète et le risque moyen en pourcentage d'événements cardiovasculaires mortels étaient plus élevés chez les personnes atteintes de SMét que chez celles qui ne l'étaient pas (18,0 % contre 7,1% pour le diabète et 4,1% contre 0,8 % pour les maladies cardiovasculaires). CONCLUSION: Le SMét est répandu chez les adultes canadiens, et une forte proportion de personnes souffrant d'un SMét ont également des affections chroniques, diagnostiquées ou non. Les estimations projetées du taux d'incidence de maladies chroniques associées à un SMét sont plus élevées chez les personnes aux prises avec ce syndrome. Par conséquent, le SMét pourrait être un facteur de risque pertinent dans l'apparition de maladies chroniques.
Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Síndrome Metabólica/epidemiologia , Obesidade/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Doença Crônica , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Estilo de Vida , Modelos Logísticos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Análise Multivariada , Avaliação das Necessidades , Aptidão Física/fisiologia , Prevalência , Medição de Risco , Índice de Gravidade de Doença , Distribuição por Sexo , Fatores Socioeconômicos , Adulto JovemRESUMO
OBJECTIVE: To compare infant outcomes between mothers with hypertension treated by beta-blockers alone and by methyldopa alone during pregnancy. DESIGN: Historical cohort study. SETTING: Saskatchewan, Canada. POPULATION: Women who delivered a singleton birth in Saskatchewan during the periods from 1 January 1980 to 30 June 1987 or from 1 January 1990 to 31 December 2005 (women who delivered between 1 July 1987 and 31 December 1989 were excluded because the information recorded on maternal drug use during pregnancy is incomplete) with a diagnosis of a hypertensive disorder during pregnancy, and who were dispensed only beta-blockers (n = 416) or only methyldopa (n = 1000). METHODS: Occurrences of adverse infant outcomes were compared between women who received beta-blockers only and women who received methyldopa only during pregnancy, first in all eligible women, and then in women with chronic hypertension and in women with gestational hypertension or pre-eclampsia/eclampsia, separately. Multiple logistic regression analyses were performed to adjust for potential confounding. MAIN OUTCOME MEASURES: Small for gestational age (SGA) < 10th percentile, SGA < 3rd percentile, preterm birth, stillbirth, institutionalisation for respiratory distress syndrome (RDS), sepsis, seizure during infancy, and infant death. RESULTS: Adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) for infants born to mothers with chronic hypertension who were dispensed beta-blockers only, as compared with infants born to mothers who were dispensed methyldopa only, during pregnancy were: 1.95 (1.21-3.15), 2.17 (1.06-4.44), and 2.17 (1.09-4.34), respectively, for SGA < 10th percentile, SGA < 3rd percentile, and being institutionalised during infancy. CONCLUSIONS: For infants born to mothers with chronic hypertension, compared with those treated by methyldopa alone, those treated by beta-blockers appear to be at increased rates of SGA and hospitalisation during infancy.
Assuntos
Antagonistas Adrenérgicos beta/efeitos adversos , Hospitalização/estatística & dados numéricos , Hipertensão Induzida pela Gravidez/epidemiologia , Recém-Nascido Pequeno para a Idade Gestacional , Complicações Cardiovasculares na Gravidez/epidemiologia , Adulto , Anti-Hipertensivos/efeitos adversos , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Recém-Nascido , Modelos Logísticos , Metildopa/efeitos adversos , Gravidez , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Saskatchewan/epidemiologia , Resultado do TratamentoRESUMO
OBJECTIVES: The objective of this study was to examine the associations of brain tumours with radio frequency (RF) fields from mobile phones. METHODS: Patients with brain tumour from the Australian, Canadian, French, Israeli and New Zealand components of the Interphone Study, whose tumours were localised by neuroradiologists, were analysed. Controls were matched on age, sex and region and allocated the 'tumour location' of their matched case. Analyses included 553 glioma and 676 meningioma cases and 1762 and 1911 controls, respectively. RF dose was estimated as total cumulative specific energy (TCSE; J/kg) absorbed at the tumour's estimated centre taking into account multiple RF exposure determinants. RESULTS: ORs with ever having been a regular mobile phone user were 0.93 (95% CI 0.73 to 1.18) for glioma and 0.80 (95% CI 0.66 to 0.96) for meningioma. ORs for glioma were below 1 in the first four quintiles of TCSE but above 1 in the highest quintile, 1.35 (95% CI 0.96 to 1.90). The OR increased with increasing TCSE 7+ years before diagnosis (p-trend 0.01; OR 1.91, 95% CI 1.05 to 3.47 in the highest quintile). A complementary analysis in which 44 glioma and 135 meningioma cases in the most exposed area of the brain were compared with gliomas and meningiomas located elsewhere in the brain showed increased ORs for tumours in the most exposed part of the brain in those with 10+ years of mobile phone use (OR 2.80, 95% CI 1.13 to 6.94 for glioma). Patterns for meningioma were similar, but ORs were lower, many below 1.0. CONCLUSIONS: There were suggestions of an increased risk of glioma in long-term mobile phone users with high RF exposure and of similar, but apparently much smaller, increases in meningioma risk. The uncertainty of these results requires that they be replicated before a causal interpretation can be made.
Assuntos
Neoplasias Encefálicas/epidemiologia , Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Neoplasias Induzidas por Radiação/epidemiologia , Doses de Radiação , Ondas de Rádio/efeitos adversos , Adulto , Algoritmos , Austrália/epidemiologia , Canadá/epidemiologia , Estudos de Casos e Controles , Feminino , França/epidemiologia , Glioma/epidemiologia , Humanos , Israel/epidemiologia , Modelos Logísticos , Masculino , Neoplasias Meníngeas/epidemiologia , Meningioma/epidemiologia , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Razão de Chances , Fatores de Risco , Fatores de TempoAssuntos
Química , Comunicação , Toxicologia/métodos , Canadá , Fortalecimento Institucional , Humanos , Pesquisa , Medição de Risco , Gestão de RiscosRESUMO
The public is increasingly concerned about risks associated with food. Food-borne diseases can easily mobilize public concerns and create strong emotional, behavioral, and political reactions with significant negative economic and psychosocial outcomes. This was observed in various countries globally experiencing the presence of prion disease bovine spongiform encephalopathy (BSE). This study highlights case-study material from various countries for key psychosocial impacts such as the public's worry and fear vis-a-vis beef consumption and the loss of confidence and trust in authorities stemming from the occurrence and management of the BSE crisis. These psychosocial impacts and resultant public behavioral responses are presented at a number of levels including individual, family, community, and societal for several European countries, with special emphasis on the UK case study. Given failures to identify the scope of individual concern about prion diseases, and to address these concerns in decision-making processes and risk communication strategies, there remains a need for further systematic research and psychosocial monitoring of the ripple effects of BSE.
Assuntos
Comportamento de Escolha , Encefalopatia Espongiforme Bovina/epidemiologia , Preferências Alimentares/psicologia , Animais , Bovinos , Coleta de Dados , Dieta , Europa (Continente)/epidemiologia , Humanos , Inquéritos e QuestionáriosRESUMO
A national public survey on public perceptions of prion disease risk in Canada was conducted from October to December 2007. The survey aimed at documenting the public's perceptions of prion diseases, within the broader context of food safety, in establishing parameters of risk acceptability. It also documented the public's perceptions of prion diseases in delineating social values and ethics that can guide Canada's future policies on prion disease risk management. In addition, the survey served to establish baseline data against which to monitor the evolution of the public's views on and understanding of this important risk issue. In total, 1517 Canadians were randomly selected to be representative of the adult population by region, age, and gender, as per the 2001 Census. This study presents descriptive findings from the survey regarding perceived risk, perceived control, uncertainty, sources of information, trust and knowledge, and beliefs pertaining to bovine spongiform encephalopathy (BSE). The survey data reveal that Canadians do not perceive mad cow disease as a salient risk but consider it more of an economic, political, social, and foreign trade issue than a public health one. Canadians are somewhat prepared to pay a premium to have a safer food supply, but not to the same extent that they desire extra measures pertaining to BSE risk management. In the context of increasing accountability in risk management decisions about food safety and population health issues, it is important to understand the way Canadians perceive such matters and identify their information needs and the factors that influence the acceptability of risks and of risk management policies.
Assuntos
Doenças Priônicas/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Animais , Canadá/epidemiologia , Bovinos , Coleta de Dados , Humanos , Pessoa de Meia-Idade , Administração em Saúde Pública , Relações Públicas , Fatores de Risco , Adulto JovemRESUMO
OBJECTIVES: The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control technologies. To improve indices of RF exposure for epidemiological studies, we assessed determinants of mobile phone output power in a multinational study. METHODS: More than 500 volunteers in 12 countries used Global System for Mobile communications software-modified phones (GSM SMPs) for approximately 1 month each. The SMPs recorded date, time, and duration of each call, and the frequency band and output power at fixed sampling intervals throughout each call. Questionnaires provided information on the typical circumstances of an individual's phone use. Linear regression models were used to analyse the influence of possible explanatory variables on the average output power and the percentage call time at maximum power for each call. RESULTS: Measurements of over 60,000 phone calls showed that the average output power was approximately 50% of the maximum, and that output power varied by a factor of up to 2 to 3 between study centres and network operators. Maximum power was used during a considerable proportion of call time (39% on average). Output power decreased with increasing call duration, but showed little variation in relation to reported frequency of use while in a moving vehicle or inside buildings. Higher output powers for rural compared with urban use of the SMP were observed principally in Sweden where the study covered very sparsely populated areas. CONCLUSIONS: Average power levels are substantially higher than the minimum levels theoretically achievable in GSM networks. Exposure indices could be improved by accounting for average power levels of different telecommunications systems. There appears to be little value in gathering information on circumstances of phone use other than use in very sparsely populated regions.
Assuntos
Telefone Celular/estatística & dados numéricos , Exposição Ambiental/análise , Ondas de Rádio , Adulto , Estudos de Casos e Controles , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Monitoramento de Radiação/métodos , Saúde da População Rural/estatística & dados numéricos , Fatores de Tempo , Saúde da População Urbana/estatística & dados numéricosRESUMO
OBJETIVE: Injuries are a significant cause of morbidity and mortality worldwide. Injuries disproportionately affect people living in low and middle income countries, including the Caribbean; however, little is known about the epidemiology of injuries in these areas. An Accident and Emergency (A&E) Department injury surveillance system was established at the San Fernando General Hospital, Trinidad and Tobago, to address this important data gap. METHODS: A detailed overview of the objectives, data collection methods, and inherent strengths and limitations of this surveillance system are presented, along with results of an analysis of data collected during the first three years of operations (from 2002 to 2004). RESULTS: Trained hospital staff collect a variety of injury/poisoning, demographic and clinical data on nearly 20 000 patients presenting each year with injury to the A&E Department. The total number of injuries in men was almost twice that in women. The majority of injuries were seen in those 25-44-years of age. Falls, other blunt force, stab/cut, traffic injury and poisoning represented the leading causes of injury. Nearly half of all the injuries occurred in the home, with the street/highway and work environments also accounting for an appreciable number of injuries. The majority of injuries were reported as unintentional. CONCLUSION: Injuries represent an important population health and health services issue in South Trinidad. Data from the A&E Department injury surveillance system represent an important resource to inform evidence-based health policy decisions on injury prevention and public health resource allocation.
OBJETIVO: Las lesiones son una causa significativa de morbilidad y mortalidad a nivel mundial. Las lesiones afectan de manera desproporcionada a la gente que vive en países de ingresos bajos y medios, incluyendo el Caribe. Sin embargo, poco se sabe acerca de la epidemiología de las lesiones en estas áreas. Con el propósito de cubrir esta laguna de importantes datos epidemiológicos, se estableció un sistema de vigilancia de lesiones en forma de Departamento de Accidentes y Emergencias (A&E), en el Hospital General San Fernando, en Trinidad y Tobago. MÉTODOS: Se presenta un resumen detallado de los objetivos, métodos de recopilación de datos, así como las fortalezas y limitaciones inherentes de este sistema de vigilancia, junto con los resultados de un análisis de los datos recogidos durante los primeros tres años de operaciones (desde 2002 al 2004). RESULTADOS: Personal entrenado del hospital recogió una variedad de datos de lesiones/ envenenamientos, así como datos demográficos y clínicos de casi 20000 pacientes que acudían con lesiones cada año al Departamento de A&E. El número total de lesiones en los hombres fue casi el doble que en las mujeres. La mayoría de las lesiones se veían en personas de 25 a 44 años de edad. Caídas, golpes contundentes, cortadas/cuchilladas, lesiones por accidentes de tráfico y envenenamiento, representan las principales causas de lesión. Casi la mitad de todas las lesiones ocurrieron en los hogares, seguidas de las producidas en la calle/autopista y los ambientes laborales, también responsables de un número apreciable de lesiones. La mayor parte de las lesiones fueron reportadas como no intencionales. CONCLUSIÓN: Las lesiones representan un asunto importante para los servicios de salud y la salud de la población del sur de Trinidad. Los datos del sistema de vigilancia de lesiones del Departamento de A&E, representan un importante recurso informativo para las decisiones sobre políticas de salud basadas en evidencias a la hora de asignar recursos para la salud pública y la prevención de lesiones.
Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Ferimentos e Lesões/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Vigilância da População , Trinidad e Tobago/epidemiologiaRESUMO
OBJECTIVE: Injuries are a significant cause of morbidity and mortality worldwide. Injuries disproportionately affect people living in low and middle income countries, including the Caribbean; however little is known about the epidemiology of injuries in these areas. An accident and emergency (A&E) department injury surveillance system was established at the San Fernando General Hospital, Trinidad and Tobago, to address this important data gap. METHODS: A detailed overview of the objectives, data collection methods, and inherent strengths and limitations of this surveillance system are presented, along with results of an analysis of data collected during the first three years of operations (from 2002 to 2004). RESULTS: Trained hospital staff collect a variety of injury/poisoning, demographic and clinical data on nearly 20,000 patients presenting each year with injury to the A&E Department. The total number of injuries in men was almost twice that in women. The majority of injuries were seen in those 25-44-years of age. Falls, other blunt force, stab/cut, traffic injury and poisoning represented the leading causes of injury. Nearly half of all the injuries occurred in the home, with the street/highway and work environments also accounting for an appreciable number of injuries. The majority of injuries were reported as unintentional. CONCLUSION: Injuries represent an important population health and health services issue in South Trinidad. Data from the A&E Department injury surveillance system represent an important resource to inform evidence-based health policy decisions on injury prevention and public health resource allocation.
Assuntos
Ferimentos e Lesões/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Vigilância da População , Trinidad e Tobago/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: To examine prescription Food and Drug Administration (FDA) C, D and X drugs in general obstetric population. STUDY DESIGN: Historical cohort study. RESULT: A total of 18 575 women who gave a birth in Saskatchewan between January 1997 and December 2000 were included. Among them, 3604 (19.4%) received FDA C, D or X drugs at least once during pregnancy. The pregnancy exposure rates were 15.8, 5.2 and 3.9%, respectively, for category C, D and X drugs, and were 11.2, 7.3 and 8.2%, respectively, in the first, second and third trimesters. Salbutamol (albuterol), trimethoprim/sulfamethoxazole (co-trimoxazole), ibuprofen, naproxen and oral contraceptives were the most common C, D, X drugs used during pregnancy. CONCLUSION: About one in every five women uses FDA C, D and X drugs at least once during pregnancy, and the most common prescription drugs in pregnancy are antiasthmatic, antibiotics, nonsteroid anti-inflammation drugs, antianxiety or antidepressants and oral contraceptives.