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Preliminary Findings of Radon Potential Indexes in Five Canadian Cities  [cached]
J. Chen,D. Moir,K. MacLellan,E. Leigh
Environment and Natural Resources Research (ENRR) , 2012, DOI: 10.5539/enrr.v2n1p2
Abstract: Radon has been identified as the second leading cause of lung cancer after tobacco smoking. Since radon in soil is believed to be the main source of radon in Canadian homes, a radon potential index determined from soil radon concentration and soil permeability can be used to describe the indoor radon potential resulting from radon in soil gas. The index increases with increasing radon concentration in soil gas and soil permeability. This study reports detailed measurements of soil gas radon concentrations and soil permeability in a total of 254 sites in five cities, Montreal, Gatineau, Ottawa, Kingston and Toronto. Average radon potential indexes were determined for each individual site of five measurement locations. The results provided additional data for the mapping of radon potentials in Canada.
Estimation of Lifetime Fatality Risk from Indoor Radon in Some Offices in a Nigerian University
O.M. Oni,G.A. Isola,O.O. Oladapo,E.A. Oni
Research Journal of Environmental and Earth Sciences , 2012,
Abstract: This study aims at estimating the lifetime cancer risk from the determination of 222Rn concentration level in some offices in Ogbomoso, Southwestern Nigeria. The measurement of the indoor 222Rn concentration levels at some offices in Ladoke Akintola University of Technology (LAUTECH) Ogbomoso, Nigeria was carried out using an active electronic radon gas detector, safety Pro3 (model HS71512) between February and July 2011. The result of the measurement showed that the average radon concentration is 26.3±4.17 Bq/m3. This value translated to an annual effective dose of 0.13 mSv/y and lifetime fatality risk of 9.94×10-6. These values which were found to be higher than values reported for some countries were however lower than the world average value and below the recommended action level. Thus, the results of this work have shown that the exposure to indoor radon at the offices considered is of low risk of fatal cancer occurrence due to radon inhalation.
Lung Cancer Risk from Occupational and Environmental Radon and Role of Smoking in Two Czech Nested Case-Control Studies  [PDF]
Ladislav Tomasek
International Journal of Environmental Research and Public Health , 2013, DOI: 10.3390/ijerph10030963
Abstract: The aim of the present study was to evaluate the risk of lung cancer from combined exposure to radon and smoking. Methodologically, it is based on case-control studies nested within two Czech cohort studies of nearly 11,000 miners followed-up for mortality in 1952–2010 and nearly 12,000 inhabitants exposed to high levels of radon in homes, with mortality follow-up in 1960–2010. In addition to recorded radon exposure, these studies use information on smoking collected from the subjects or their relatives. A total of 1,029 and 370 cases with smoking information have been observed in the occupational and environmental (residential) studies, respectively. Three or four control subjects have been individually matched to cases according to sex, year of birth, and age. The combined effect from radon and smoking is analyzed in terms of geometric mixture models of which the additive and multiplicative models are special cases. The resulting models are relatively close to the additive interaction (mixing parameter 0.2 and 0.3 in the occupational and residential studies, respectively). The impact of the resulting model in the residential radon study is illustrated by estimates of lifetime risk in hypothetical populations of smokers and non-smokers. In comparison to the multiplicative risk model, the lifetime risk from the best geometric mixture model is considerably higher, particularly in the non-smoking population.
Radon in caves: clinical aspects  [PDF]
Craven Stephen A.,Smit Berend J.
International Journal of Speleology , 2006,
Abstract: Historical, experimental and clinical evidence is presented to suggest that radon constitutes a relatively small carcinogenic risk for casual visitors to caves. The risk is dependent on radon levels and the smoking of tobacco. Show cave guides, chronically exposed to radon, may be at increased risk for lung cancer due to the effects of radon, especially if they are smokers of tobacco.
Lifetime intimate partner violence exposure, attitudes and comfort among Canadian health professions students
Megan R Gerber, André KW Tan
BMC Research Notes , 2009, DOI: 10.1186/1756-0500-2-191
Abstract: Students in the schools of Medicine, Nursing and Rehabilitation at a university in Ontario attend an annual daylong interprofessional IPV training. To measure perceived role and comfort with IPV and prior personal exposure, we administered a brief Likert scale survey to a convenience sample of students over three years. 552 students completed the survey; the overall response rate was 73%. The majority (82%) agreed that it was their role to intervene in cases of IPV; however Rehabilitation students expressed lower overall comfort levels than did their peers in other schools (p < .0001). Gender, age and prior training on the subject were not significant predictors of comfort. Seven percent reported lifetime IPV and one-fifth had witnessed IPV, but these exposures did not predict comfort in adjusted logistic regression models.While the majority of professional students believe it is their role to address IPV in clinical practice, comfort level varied significantly by field of study. More than one fifth of the students reported some personal exposure to IPV. However this did not impact their level of comfort in addressing this issue. Educators need to take students' preexisting attitudes and personal exposure into account when planning curriculum initiatives in this area.Intimate partner violence (IPV) is a pattern of coercive behavior in which one person attempts to control another through threats or actual use of physical violence, sexual assault and verbal or psychological abuse. [1] Nearly one-third of Canadian women experience IPV in their lifetime and 21.2% report IPV in the preceding 5 years. [2,3] In Canadian family practice settings, the estimated prevalence is 14.6%. [4] IPV has well-established adverse health effects, [5-7] and results in frequent and regular contact between victims and healthcare providers. [4,8] It has thus become widely accepted that training of healthcare professionals is imperative. [9,10] Yet, the sensitive nature of IPV creates challen
Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: The Case of Radon and Smoking  [PDF]
Teresa Chahine,Bradley D. Schultz,Valerie G. Zartarian,Jianping Xue,S. V. Subramanian,Jonathan I. Levy
International Journal of Environmental Research and Public Health , 2011, DOI: 10.3390/ijerph8093688
Abstract: Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case example, given its large attributable risk, effect modification due to smoking, and significant variability in radon concentrations and smoking patterns. In spite of this fact, no study to date has estimated geographic and sociodemographic patterns of both radon and smoking in a manner that would allow for inclusion of radon in community-based cumulative risk assessment. In this study, we apply multi-level regression models to explain variability in radon based on housing characteristics and geological variables, and construct a regression model predicting housing characteristics using U.S. Census data. Multi-level regression models of smoking based on predictors common to the housing model allow us to link the exposures. We estimate county-average lifetime lung cancer risks from radon ranging from 0.15 to 1.8 in 100, with high-risk clusters in areas and for subpopulations with high predicted radon and smoking rates. Our findings demonstrate the viability of screening-level assessment to characterize patterns of lung cancer risk from radon, with an approach that can be generalized to multiple chemical and non-chemical stressors.
Use of groundwater lifetime expectancy for the performance assessment of a deep geologic radioactive waste repository:2. Application to a Canadian Shield environment  [PDF]
Y. -J. Park,F. J. Cornaton,S. D. Normani,J. F. Sykes,E. A. Sudicky
Physics , 2011, DOI: 10.1029/2007WR006212
Abstract: Cornaton et al. [2007] introduced the concept of lifetime expectancy as a performance measure of the safety of subsurface repositories, based upon the travel time for contaminants released at a certain point in the subsurface to reach the biosphere or compliance area. The methodologies are applied to a hypothetical but realistic Canadian Shield crystalline rock environment, which is considered to be one of the most geologically stable areas on Earth. In an approximately 10\times10\times1.5 km3 hypothetical study area, up to 1000 major and intermediate fracture zones are generated from surface lineament analyses and subsurface surveys. In the study area, mean and probability density of lifetime expectancy are analyzed with realistic geologic and hydrologic shield settings in order to demonstrate the applicability of the theory and the numerical model for optimally locating a deep subsurface repository for the safe storage of spent nuclear fuel. The results demonstrate that, in general, groundwater lifetime expectancy increases with depth and it is greatest inside major matrix blocks. Various sources and aspects of uncertainty are considered, specifically geometric and hydraulic parameters of permeable fracture zones. Sensitivity analyses indicate that the existence and location of permeable fracture zones and the relationship between fracture zone permeability and depth from ground surface are the most significant factors for lifetime expectancy distribution in such a crystalline rock environment. As a consequence, it is successfully demonstrated that the concept of lifetime expectancy can be applied to siting and performance assessment studies for deep geologic repositories in crystalline fractured rock settings.
Vegetable and Fruit Intakes of On-Reserve First Nations Schoolchildren Compared to Canadian Averages and Current Recommendations  [PDF]
Allison Gates,Rhona M. Hanning,Michelle Gates,Kelly Skinner,Ian D. Martin,Leonard J. S. Tsuji
International Journal of Environmental Research and Public Health , 2012, DOI: 10.3390/ijerph9041379
Abstract: This study investigated, in on-reserve First Nations (FN) youth in Ontario, Canada, the following: (a) the intakes of vegetable and fruit, “other” foods and relevant nutrients as compared to current recommendations and national averages, (b) current prevalence rates of overweight and obesity and (c) the relationship between latitude and dietary intakes. Twenty-four-hour diet recalls were collected via the Waterloo Web-Based Eating Behaviour Questionnaire (WEB-Q) (n = 443). Heights and weights of participants were self reported using measured values and Body Mass Index was categorized using the International Obesity Task Force cutoffs. Food group and nutrient intakes were compared to current standards, Southern Ontario Food Behaviour data and the Canadian Community Health Survey, Cycle 2.2, using descriptive statistics. Mean vegetable and fruit, fibre and folate intakes were less than current recommendations. Girls aged 14–18 years had mean intakes of vitamin A below current recommendations for this sub-group; for all sub-groups, mean intakes of vegetables and fruit were below Canadian averages. All sub-groups also had intakes of all nutrients and food groups investigated that were less than those observed in non-FN youth from Southern Ontario, with the exception of “other” foods in boys 12–18 years. Prevalence rates of overweight and obesity were 31.8% and 19.6%, respectively, exceeding rates in the general population. Dietary intakes did not vary consistently by latitude (n = 248), as revealed by ANOVA. This study provided a unique investigation of the dietary intakes of on-reserve FN youth in Ontario and revealed poor intakes of vegetables and fruit and related nutrients and high intakes of “other” foods. Prevalence rates of overweight and obesity exceed those of the general population.
The role of information in a lifetime process - a model of weight maintenance by women over long time periods
Judit Bar-Ilan,Nira Shalom,Snunith Shoham,Shifra Baruchson-Arbib
Information Research: an international electronic journal , 2006,
Abstract: Introduction. This paper proposes a model of information behaviour of women during their life-long struggle to maintain normal weight. Method. The model is integrative and contextual, built on existing models in information science and several other disciplines, and the life stories of about fifty Israeli women aged 25-55 and interviews with professionals. Analysis. The life stories of the participating women were analyzed qualitatively, major themes and phases were identified. Results. Weight loss and/or maintenance behaviour is a lifetime process in which distinctive stages were identified. In most cases the weight gain - weight loss - maintenance cycle is a recurring cycle. Information is a major resource during the process: several roles of information were defined: enabling, motivating, reinforcing, providing background information related to weight problems and creating the internal cognitive schema related to food and weight. Information behaviour and the roles of information vary with the different stages. Information needs are also influenced by the specific stage of the process. Information gathered at previous cycles is reused, and information gained through previous experience effects behaviour in the current cycle. Conclusion. The model has both theoretical and practical implications.
Assessment of Radon level in dwellings of Tabriz  [cached]
Gholamhassan Haddadi
Journal of Fasa University of Medical Sciences , 2011,
Abstract: Background & Objective: Indoor radon gas (222Rn) has been recognized as one of the causes of lung cancer. The presence of radioactive radium in the construction & materials in the buildings its changes in contact with radon gas may lead to increase level of radon gas in the residential houses. In this regards, indoor radon measurement is important. This study was conducted to determine radon concentration in Tabriz houses. Materials & Methods: In this study, 196 radon diffusion dosimeters were left in different floors of houses constructed with different materials such as cement (betony), heated brick & clay with raw brick at every floor for 6 months. The “electrochemical etching” method was applied to detect “alpha tracks” on the polymers of dosimeters and based on number of these tracks, radon concentration was determined. Results: This study showed that average radon concentration were 39Bqm-3 in the houses. At different floors & different construction material the average effective dose equivalent of lung tissue was 0.97msvy-1. Conclusion: Based on these results, it can be concluded that, the indoor radon levels in the Tabriz houses are within acceptable range.
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