The reduction of birth weight by fine particulate matter and its modification by maternal and neighbourhood-level factors: a multilevel analysis in British Columbia, Canada.

BACKGROUND: The purpose of this research was to determine the relationship between modeled particulate matter (PM2.5) exposure and birth weight, including the potential modification by maternal risk factors and indicators of socioeconomic status (SES). METHODS: Birth records from 2001 to 2006 (N = 231,929) were linked to modeled PM2.5 data from a national land-use regression model along with neighbourhood-level SES and socio-demographic data using 6-digit residential postal codes. Multilevel random coefficient models were used to estimate the effects of PM2.5, SES and other individual and neighbourhood-level covariates on continuous birth weight and test interactions. Gestational age was modeled with a random slope to assess potential neighbourhood-level differences of its effect on birth weight and whether any between-neighbourhood variability can be explained by cross-level interactions. RESULTS: Models adjusted for individual and neighbourhood-level covariates showed a significant non-linear negative association between PM2.5 and birth weight explaining 8.5 % of the between-neighbourhood differences in mean birth weight. A significant interaction between SES and PM2.5 was observed, revealing a more pronounced negative effect of PM2.5 on birth weight in lower SES neighbourhoods. Further positive and negative modification of the PM2.5 effect was observed with maternal smoking, maternal age, gestational diabetes, and suspected maternal drug or alcohol use. The random intercept variance indicating between-neighbourhood birth weight differences was reduced by 75 % in the final model, while the random slope variance for between-neighbourhood gestational age effects remained virtually unchanged. CONCLUSION: We provide evidence that neighbourhood-level SES variables and PM2.5 have both independent and interacting associations with birth weight, and together account for 49 % of the between-neighbourhood differences in birth weight. Evidence of effect modification of PM2.5 on birth weight across various maternal and neighbourhood-level factors suggests that certain sub-populations may be more or less vulnerable to relatively low doses PM2.5 exposure.

Air pollution, neighbourhood and maternal-level factors modify the effect of smoking on birth weight: a multilevel analysis in British Columbia, Canada.

BACKGROUND: Maternal smoking during pregnancy negatively impacts fetal growth, but the effect is not homogenous across the population. We sought to determine how the relationship between cigarette use and fetal growth is modified by the social and physical environment. METHODS: Birth records with covariates were obtained from the BC Perinatal Database Registry (N = 232,291). Maternal smoking status was self-reported as the number of cigarettes smoked per day usually at the first prenatal care visit. Census dissemination areas (DAs) were used as neighbourhood-level units and linked to individual births using residential postal codes to assign exposure to particulate air pollution (PM2.5) and neighbourhood-level attributes such as socioeconomic status (SES), proportion of post-secondary education, immigrant density and living in a rural place. Random coefficient models were used with cigarettes/day modeled with a random slope to estimate its between-DA variability and test cross-level interactions with the neighbourhood-level variables on continuous birth weight. RESULTS: A significant negative and non-linear association was found between maternal smoking and birth weight. There was significant between-DA intercept variability in birth weight as well as between-DA slope variability of maternal smoking on birth weight of which 68 and 30 % respectively was explained with the inclusion of DA-level variables and their cross-level interactions. High DA-level SES had a strong positive association with birth weight but the effect was moderated with increased cigarettes/day. Conversely, heavy smokers showed the largest increases in birth weight with rising neighbourhood education levels. Increased levels of PM2.5 and immigrant density were negatively associated with birth weight, but showed positive interactions with increased levels of smoking. Older maternal age and suspected drug or alcohol use both had negative interactions with increased levels of maternal smoking. CONCLUSION: Maternal smoking had a negative and non-linear dose-response association with birth weight which was highly variable between neighbourhoods and evidence of effect modification with neighbourhood-level factors. These results suggest that focusing exclusively on individual behaviours may have limited success in improving outcomes without addressing the contextual influences at the neighbourhood-level. Further studies are needed to corroborate our findings and to understand how neighbourhood-level attributes interact with smoking to affect birth outcomes.

A survey of food bank operations in five Canadian cities.

BACKGROUND: Food banks have emerged in response to growing food insecurity among low-income groups in many affluent nations, but their ability to manage this problem is questionable. In Canada, in the absence of public programs and policy interventions, food banks are the only source of immediate assistance for households struggling to meet food needs, but there are many indications that this response is insufficient. The purpose of this study was to examine the factors that facilitate and limit food bank operations in five Canadian cities and appraise the potential of these initiatives to meet food needs. METHODS: An inventory of charitable food provisioning in Halifax, Quebec City, Toronto, Edmonton, and Victoria, Canada was conducted in 2010. Of the 517 agencies that participated in a telephone survey of their operations, 340 were running grocery programs. Multivariate regression analyses were conducted to determine the association between program characteristics, volume of service, and indicators of strain in food banks' abilities to consistently achieve the standards of assistance they had established. RESULTS: Extensive, well-established food bank activities were charted in each city, with the numbers of people assisted ranging from 7,111 in Halifax to 90,141 in Toronto per month. Seventy-two percent of agencies indicated that clients needed more food than they provided. The number of people served by any one agency in the course of a month was positively associated with the proportion of food distributed that came from donations (beta 0.0143, SE 0.0024, p 0.0041) and the number of volunteers working in the agency (beta 0.0630, SE 0.0159, p 0.0167). Food banks only achieved equilibrium between supply and demand when they contained demand through restrictions on client access. When access to assistance was less restricted, the odds of food banks running out of food and invoking measures to ration remaining supplies and restrict access rose significantly. CONCLUSIONS: Despite their extensive history, food banks in Canada remain dependent on donations and volunteers, with available resources quickly exhausted in the face of agencies' efforts to more fully meet clients' needs. Food banks have limited capacity to respond to the needs of those who seek assistance.

Psychosocial and other working conditions: variation by employment arrangement in a sample of working Australians.

BACKGROUND: The evidence linking precarious employment with poor health is mixed. Self-reported occupational exposures in a population-based Australian sample were assessed to investigate the potential for differential exposure to psychosocial and other occupational hazards to contribute to such a relationship, hypothesizing that exposures are worse under more precarious employment arrangements (EA). METHODS: Various psychoscial and other working conditions were modeled in relation to eight empirically derived EA categories with Permanent Full-Time (PFT) as the reference category (N = 925), controlling for sex, age, and occupational skill level. RESULTS: More precarious EA were associated with higher odds of adverse exposures. Casual Full-Time workers had the worst exposure profile, showing the lowest job control, as well as the highest odds of multiple job holding, shift work, and exposure to four or more additional occupational hazards. Fixed-Term Contract workers stood out as the most likely to report job insecurity. Self-employed workers showed the highest job control, but also the highest odds of long working hours. CONCLUSIONS: Psychosocial and other working conditions were generally worse under more precarious EA, but patterns of adverse occupational exposures differ between groups of precariously employed workers.

Job strain and shift work influences on biomarkers and subclinical heart disease indicators: a pilot study.

This pilot study is one of the first to examine the impact of job strain and shift work on both the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenal (HPA) axis using two salivary stress biomarkers and two subclinical heart disease indicators. This study also tested the feasibility of a rigorous biological sampling protocol in a busy workplace setting. Paramedics (n = 21) self-collected five salivary samples over 1 rest and 2 workdays. Samples were analyzed for α-amylase and cortisol diurnal slopes and daily production. Heart rate variability (HRV) was logged over 2 workdays with the Polar RS800 Heart Rate monitors. Endothelial functioning was measured using fingertip peripheral arterial tonometry. Job strain was ascertained using a paramedic-specific survey. The effects of job strain and shift work were examined by comparing paramedic types (dispatchers vs. ambulance attendants) and shift types (daytime vs. rotating day/night). Over 90% of all expected samples were collected and fell within expected normal ranges. Workday samples were significantly different from rest day samples. Dispatchers reported higher job strain than ambulance paramedics and exhibited reduced daily alpha-amylase production, elevated daily cortisol production, and reduced endothelial function. In comparison with daytime-only workers, rotating shift workers reported higher job strain, exhibited flatter α-amylase and cortisol diurnal slopes, reduced daily α-amylase production, elevated daily cortisol production, and reduced HRV and endothelial functioning. Despite non-statistically significant differences between group comparisons, the consistency of the overall trend in subjective and objective measures suggests that exposure to work stressors may lead to dysregulation in neuroendocrine activity and, over the long-term, to early signs of heart disease. Results suggest that further study is warranted in this population. Power calculations based on effect sizes in the shift type comparison suggest a study size of n = 250 may result in significant differences at p = 0.05. High compliance among paramedics to complete the intensive protocol suggests this study will be feasible in a larger population.

Injury risk associated with physical demands and school environment characteristics among a cohort of custodial workers.

Few epidemiological studies have investigated the relationship between work exposures and injury risk among custodians. The relationship between injury risk and occupational physical demands (e.g. pushing/pulling, lifting) and school environment characteristics (e.g. school type, season) was investigated among a cohort of 581 school custodians over a 4-year period. In the final Poisson regression models, the risk of injury was associated with time spent in pushing/pulling tasks in a dose-response manner increasing to a five-fold risk among the highest quartile of exposure (risk ratio = 5.15, 95% CI 1.00, 26.5). Injury risk was also associated with working during the school year compared to the summer, working in a school with grass vs. gravel grounds and working in a school with detached classrooms. Results help to target interventions such as alternative methods for floor cleaning to reduce the pushing/pulling demands of custodial work and to support decisions for alternatives to detached classrooms and grass surfaces. Statement of Relevance: This study examines ergonomic factors (physical demand exposures, school environment characteristics) associated with injury risk among custodial school workers. The findings help schools to target interventions to reduce the physical demands associated with injuries and to design school environments to reduce exposures.

Mental health differences among middle-aged sawmill workers in rural compared to urban British Columbia.

The study sought to determine whether differences in mental health outcomes were observable in a cohort of workers living in rural compared to urban places in the Canadian province of British Columbia. The study was based on a cohort of male sawmill workers. The cohort was probabilistically linked to the BC Linked Health Database in order to yield objective mental health outcomes. A nested case control design was used. Univariate and multivariate models were constructed using conditional logistic regression. While results differed according to the particular mental health outcome, after controlling for socio-economic confounders it was found that workers who remained in or migrated to rural places tended to have better mental health outcomes than workers who remained in or migrated to urban places.

Charitable food programs in Victoria, BC.

PURPOSE: Few authors have investigated the institutional character of charitable food programs and their capacity to address food security in Canada. METHODS: We surveyed food program managers at charitable agencies in Greater Victoria, British Columbia. We discuss the structure of the "system" of charitable food provision, the value of sourced food, types of services provided, clients' demographic profile, and the estimated healthfulness of meals served. We also describe the proportion of major food types purchased and donated to agencies. RESULTS: Thirty-six agencies served approximately 20,000 meals a week to about 17,000 people. Food valued at $3.2 million was purchased or donated; approximately 50% was donated, mainly by corporations. The largest value of food purchased and donated was from meat and alternatives (40.9%) and nonperishable food items (16%). Dairy products made up the smallest share of donated foods. CONCLUSIONS: Charitable food programs in Victoria depend on food donations. The proportion of dairy products and produce is low, which raises questions about the healthfulness of foods currently fed to homeless and poor people in the city.

Work disability prevention in rural healthcare workers.

INTRODUCTION: Approximately 20% of healthcare workers in high-income countries such as Australia, Canada and the USA work in rural areas. Healthcare workers are known to be vulnerable to occupational injury and poor work disability outcomes; given their rural-urban distribution, it is possible to compare work disability prevention in rural and urban areas. However, little attention has been paid to work disability prevention issues specific to rural workers, including rural healthcare workers. A comprehensive review of the literature was conducted to identify rural-urban differences in work disability outcomes (defined as the incidence of occupational injury and the duration of associated work absence), as well as risk factors for poor work disability outcomes in rural healthcare workers. METHODS: The databases MEDLINE, CINAHL, and EMBASE were searched, as were relevant research centers and government agencies, to identify all quantitative and qualitative English-language studies published between 1 January 2000 and 6 October 2009 that discussed occupational injury, work absence duration, work disability management, or risk factors for poor work disability outcomes, for rural workers specifically, or in comparison with urban workers. To ensure inclusion of studies of healthcare workers as a distinct group among other sector-specific groups, a broad search for literature related to all industrial sectors was conducted. RESULTS: Of 860 references identified, 5 discussed work disability outcomes and 25 discussed known risk factors. Known risk factors were defined as factors firmly established to be associated with poor work disability outcomes in the general worker population based on systematic reviews, well-established conceptual models of work disability prevention, and public health literature. Although somewhat conflicting, the evidence suggests that rural healthcare workers experience higher rates of occupational injury compared with urban healthcare workers, within occupational categories. Rural workers also appear to be more vulnerable to prolonged work absence although the data are limited. No studies directly compared risk factors for work disability prevention outcomes between rural and urban healthcare workers. However, potential risk factors were identified at the level of the environment, worker, job, organization, worker compensation system and healthcare access. Important methodological limitations were noted, including unclear definitions of rurality, inadequate methods of urban-rural comparisons such as comparing samples from different countries, and a paucity of studies applying longitudinal or multivariate designs. CONCLUSIONS: There is a notable lack of evidence about work disability prevention issues for healthcare workers in rural areas. Available evidence supports the hypothesis that rural healthcare workers are vulnerable to occupational injury, and suggests they are vulnerable to prolonged work absence. They may be particularly vulnerable to poor work disability prevention outcomes due to complex patient needs in the context of risk factors such as heavy workloads, long hours, heavy on-call demands, high stress levels, limited support and workplace violence. Additional vulnerability may occur because their work conditions are managed in distant urban administrative centers, and due to barriers in their own healthcare access. Although rural healthcare workers seem generally at greater risk of injury, one study suggests that urban emergency medical service workers experience a high vulnerability to injury that may outweigh the effects of rurality. Additional research is needed to document rural-urban disparities in work disability outcomes and to identify associated sources and risk factors. Other issues to address are access to and quality of healthcare for rural healthcare workers, streamlining the compensation system, the unique needs of Aboriginal healthcare workers, and the management of prolonged work absence. Finally, occupational injury and work absence duration programs should be tailored to meet the needs of rural workers.

Job strain exposures vs. stress-related workers' compensation claims in Victoria, Australia: developing a public health response to job stress.

We present a comparative analysis of patterns of exposure to job stressors and stress-related workers' compensation (WC) claims to provide an evaluation of the adequacy of claims-driven policy and practice. We assessed job strain prevalence in a 2003 population-based survey of Victorian [Australia] workers and compared these results with stress-related WC statistics for the same year. Job strain prevalence was higher among females than males, and elevated among lower vs. higher occupational skill levels. In comparison, claims were higher among females than males, but primarily among higher skill-level workers. There was some congruence between exposure and WC claims patterns. Highly exposed groups in lower socio-economic positions were underrepresented in claims statistics, suggesting that the WC insurance perspective substantially underestimates the job stress problems for these groups. Thus to provide a sufficient evidence base for equitable policy and practice responses to this growing public health problem, exposure or health outcome data are needed as an essential complement to claims statistics.

Unwanted sexual advances at work: variations by employment arrangement in a sample of working Australians.

OBJECTIVE: We tested the hypothesis that the risk of experiencing unwanted sexual advances at work (UWSA) is greater for precariously-employed workers in comparison to those in permanent or continuing employment. METHODS: A cross-sectional population-based telephone survey was conducted in Victoria (66% response rate, N=1,101). Employment arrangements were analysed using eight differentiated categories, as well as a four-category collapsed measure to address small cell sizes. Self-report of unwanted sexual advances at work was modelled using multiple logistic regression in relation to employment arrangement, controlling for gender, age, and occupational skill level. RESULTS: Forty-seven respondents reported UWSA in our sample (4.3%), mainly among women (37 of 47). Risk of UWSA was higher for younger respondents, but did not vary significantly by occupational skill level or education. In comparison to Permanent Full-Time, three employment arrangements were strongly associated with UWSA after adjustment for age, gender, and occupational skill level: Casual Full-Time OR = 7.2 (95% Confidence Interval 1.7-30.2); Fixed-Term Contract OR = 11.4 (95% CI 3.4-38.8); and Own-Account Self-Employed OR = 3.8 (95% CI 1.2-11.7). In analyses of females only, the magnitude of these associations was further increased. CONCLUSIONS: Respondents employed in precarious arrangements were more likely to report being exposed to UWSA, even after adjustment for age and gender. IMPLICATIONS: Greater protections from UWSA are likely needed for precariously employed workers.

A case control study of differences in non-work injury and accidents among sawmill workers in rural compared to urban British Columbia, Canada.

BACKGROUND: Using a cohort of British Columbian male sawmill workers, we conducted a nested case-control study of the impact of rural compared to urban residence as well as rural/urban migration patterns in relation to hospitalization for non-work injury. We postulate that for many types of non-work injuries, rates will be higher in rural communities than in urban ones and that rates will also be higher for workers who migrate from urban to rural communities. METHODS: Using conditional logistic regression, univariate models were first run with each of five non-work injury outcomes. These outcomes were hospitalizations due to assault, accidental poisoning, medical mis-adventure, motor vehicle trauma, and other non-work injuries. In multivariate models marital status, ethnicity, duration of employment, and occupation were forced into the model and associations with urban, compared to rural, residence and various urban/migration patterns were tested. RESULTS: Urban or rural residence and migration status from urban to other communities, and across rural communities, were not associated with hospitalization for medical misadventure, assault, or accidental poisoning. The likelihood of a rural resident being hospitalized for motor vehicle trauma is higher than for an urban resident. The likelihood that a rural resident is hospitalized for "other" non-work injury is higher than for an urban resident. CONCLUSION: In a relatively homogenous group of workers, and using a rigorous study design, we have demonstrated that the odds of other non-work injury are much higher for workers resident in and migrating to rural regions of Canada than they are for workers resident in or migrating to urban places.

Regions, hospitals and health outcomes over time: A multi-level analysis of repeat prevalence among a cohort of health-care workers.

BACKGROUND: The relative importance of region, workplace, and individual determinants of health burden is debated. OBJECTIVE: To model the contribution of hospital characteristics to employee mental and musculoskeletal disorders. METHODS: We linked employment records of nurses and support services' staff with health records, neighbourhood census, and hospital administrative data. We conducted multi-level logistic regression analyses with three levels: year (I), employee characteristics (II), and hospital characteristics (III). RESULTS: Northern region hospitals experienced lower disorder prevalences (odds ratios (OR) 0.58, 95% confidence intervals (0.40, 0.82) for mental and 0.56 (0.44, 0.73) for musculoskeletal disorders). Hospitals with yearly workloads of the highest versus lowest quintiles of inpatient days/1000 employee hours (>86.0 vs. <42.6) and surgical cases/1000 employee hours (>10.5 vs. <3.9) had greater odds of mental (1.29 (1.05, 1.57); 1.22 (1.05, 1.42)) and musculoskeletal (1.38 (1.21, 1.58); 1.21 (1.09, 1.34)) disorders. CONCLUSION: Opportunities exist for reduction in burden with hospital workload reduction. Further exploration of regional effects is needed.

Globalization and the marginalization of unskilled labor: potential impacts on health in developed nations.

The objective of this investigation was to determine the impacts of economic globalization on labor markets and outline potential pathways for these changes to affect health status in industrialized nations. A systematic review of the economic globalization and health literature revealed that, under the impact of globalization and market deregulation, the past 25 years have witnessed de-industrialization, shifts to nontraditional, insecure work arrangements, and relatively high levels of unemployment in most developed nations. This has occurred in the context of hypermobility of capital, relative immobility of labor, and declining market position for unskilled labor. Such structural changes in the labor markets in conjunction with shifts in educational opportunities and requirements have resulted in the increasing marginalization of unskilled workers from the labor market. Aside from direct effects on health due to the threat and experience of unemployment, and given that income inequality within nations is a main driver of national health status, lowered relative wages for the unskilled will probably affect national health status through increased income inequality.

The foundations of National public hospital insurance.

This paper provides the background to provincial and federal government acceptance of a public hospital insurance plan. I describe the development of two-tiered hospitals to the 1920s and the failure of private hospital financing as the Depression unfolded. I then discuss developments in Saskatchewan climaxing in the first provincial public hospital insurance plan and the continuing fiscal stresses facing hospitals in provinces without public plans. Finally, I outline the main reasons why all the provinces signed onto a national public hospital insurance plan.

Job strain - attributable depression in a sample of working Australians: assessing the contribution to health inequalities.

BACKGROUND: The broad aim of this study was to assess the contribution of job strain to mental health inequalities by (a) estimating the proportion of depression attributable to job strain (low control and high demand jobs), (b) assessing variation in attributable risk by occupational skill level, and (c) comparing numbers of job strain-attributable depression cases to numbers of compensated 'mental stress' claims. METHODS: Standard population attributable risk (PAR) methods were used to estimate the proportion of depression attributable to job strain. An adjusted Odds Ratio (OR) of 1.82 for job strain in relation to depression was obtained from a recently published meta-analysis and combined with exposure prevalence data from the Australian state of Victoria. Job strain exposure prevalence was determined from a 2003 population-based telephone survey of working Victorians (n = 1101, 66% response rate) using validated measures of job control (9 items, Cronbach's alpha = 0.80) and psychological demands (3 items, Cronbach's alpha = 0.66). Estimates of absolute numbers of prevalent cases of depression and successful stress-related workers' compensation claims were obtained from publicly available Australian government sources. RESULTS: Overall job strain-population attributable risk (PAR) for depression was 13.2% for males [95% CI 1.1, 28.1] and 17.2% [95% CI 1.5, 34.9] for females. There was a clear gradient of increasing PAR with decreasing occupational skill level. Estimation of job strain-attributable cases (21,437) versus "mental stress" compensation claims (696) suggest that claims statistics underestimate job strain-attributable depression by roughly 30-fold. CONCLUSION: Job strain and associated depression risks represent a substantial, preventable, and inequitably distributed public health problem. The social patterning of job strain-attributable depression parallels the social patterning of mental illness, suggesting that job strain is an important contributor to mental health inequalities. The numbers of compensated 'mental stress' claims compared to job strain-attributable depression cases suggest that there is substantial under-recognition and under-compensation of job strain-attributable depression. Primary, secondary, and tertiary intervention efforts should be substantially expanded, with intervention priorities based on hazard and associated health outcome data as an essential complement to claims statistics.

Paternal psychosocial work conditions and mental health outcomes: a case-control study.

BACKGROUND: The role of social and family environments in the development of mental health problems among children and youth has been widely investigated. However, the degree to which parental working conditions may impact on developmental psychopathology has not been thoroughly studied. METHODS: We conducted a case-control study of several mental health outcomes of 19,833 children of sawmill workers and their association with parental work stress, parental socio-demographic characteristics, and paternal mental health. RESULTS: Multivariate analysis conducted with four distinct age groups (children, adolescents, young adults, and adults) revealed that anxiety based and depressive disorders were associated with paternal work stress in all age groups and that work stress was more strongly associated with alcohol and drug related disorders in adulthood than it was in adolescence and young adulthood. CONCLUSION: This study provides support to the tenet that being exposed to paternal work stress during childhood can have long lasting effects on the mental health of individuals.

Sexually transmitted infection (STI) testing among young oil and gas workers: the need for innovative, place-based approaches to STI control.

BACKGROUND: Northeastern British Columbia is undergoing rapid in-migration of young, primarily male workers in response to the "boom" in the oil/gas industries. Accompanying the boom is a rise in Chlamydia rates among youth, which exceed the provincial average by 22%. STI testing reduces the disease burden, contributing to STI prevention. OBJECTIVES: 1) To document youths' perceptions regarding the socio-cultural and structural forces that affect young oil/gas workers' access to STI testing; 2) to gather service providers' perspectives on sexual health service delivery for workers; and 3) to develop recommendations to improve the accessibility of STI testing. METHODS: We conducted ethnographic fieldwork (8 weeks) in a remote oil/gas community, including in-depth interviews with 25 young people (ages 15-25) and 14 health and social service providers. RESULTS: Participants identified limited opportunities to access testing, geographic isolation, and 'rigger' culture as three key categories inhibiting STI testing among oil/gas Workers. DISCUSSION: These results suggest the need for place-based approaches to STI control. Innovative outreach strategies are suggested to address oil/gas workers' needs, including a locally tailored STI awareness campaign, condom distribution, expanded clinic hours, and onsite STI testing.

Barriers to STI testing among youth in a Canadian oil and gas community.

Northeastern British Columbia, Canada, is undergoing in-migration of young people attracted by jobs in the oil/gas sectors. Chlamydia rates among youth ages 15-24 are increasing and exceed the provincial average by 22%. Testing for sexually transmitted infections (STIs) reduces the disease burden, contributing to prevention. We conducted ethnographic fieldwork, including interviews with 25 youth and 14 service providers, to document their perceptions regarding youth's access to STI testing. Five key barriers to access were identified: limited opportunities for access, geographic inaccessibility, local social norms, limited information, and negative interactions with providers. To address youths' needs, we recommend active STI prevention and testing service delivery models that incorporate a locally tailored public awareness campaign, outreach to oil/gas workers, condom distribution, expanded clinic hours and drop-in STI testing, specialized training for health care providers, and inter-sectoral partnerships between public health, non-profit organizations, and industry.

Work, obesity, and occupational safety and health.

There is increasing evidence that obesity and overweight may be related, in part, to adverse work conditions. In particular, the risk of obesity may increase in high-demand, low-control work environments, and for those who work long hours. In addition, obesity may modify the risk for vibration-induced injury and certain occupational musculoskeletal disorders. We hypothesized that obesity may also be a co-risk factor for the development of occupational asthma and cardiovascular disease that and it may modify the worker's response to occupational stress, immune response to chemical exposures, and risk of disease from occupational neurotoxins. We developed 5 conceptual models of the interrelationship of work, obesity, and occupational safety and health and highlighted the ethical, legal, and social issues related to fuller consideration of obesity's role in occupational health and safety.