Prevalence of exposure to solar ultraviolet radiation (UVR) on the job in Canada

A Genomic Approach to Identify the Different between Acute and Chronic UVB Exposures in the Causation of Inflammation and Cancer

As a principal component of solar radiation, ultraviolet B (UVB) exposure can be harmful depending on the duration and intensity because the human body can easily be exposed to it. Many studies have demonstrated that UVB causes a series of inflammatory and other skin disorders. UVB has been classified as the Group 1 carcinogen by the International Agency for Research on Cancer. Diverse studies have focused on UVB exposure but the complex perspective of acute and chronic UVB exposure is still lacking. This review presents the differences between acute and chronic exposure to UVB and summarizes public information in terms of toxicogenomic characteristics. We also demonstrated the differences between adverse effects of acute and chronic UVB exposure on the skin system. From the published literatures, we compared the biological pathways predict of the adverse effects caused by each UVB exposure type. Furthermore, our review not only clarifies the differences in each UVB exposure network but also suggests major hub genes related to cellular mechanisms and diseases that are thought to be affected by acute and chronic UVB exposure.

The Burden of Plastic Surgery Related Disease in Canada: A Perspective Based on the 2019 Global Burden of Disease Study

Purpose: Identifying the burden of disease related to plastic and reconstructive surgery in Canada will provide timely population-based data, inform policy, and generate support for research funding. Methods and Patients: Data on the burden of disease (ie, prevalence, incidence, mortality, years of life lost, years lived with disability, and disability-adjusted life years [DALYs]), were extracted from the Global Burden of Disease 2019 results tool for all available and relevant plastic surgery diseases. The economic burden of disease in Canadian dollars was calculated based on prior studies. Data are presented as either rates (per 100 000) or counts with the associated uncertainty interval. Results: In 2019, plastic surgery related conditions in Canada had an overall age-standardized DALY rate of 556 per 100 000 [463-664]. Of these conditions, breast cancer was responsible for approximately 50% of the overall burden of disease, with an age-standardized DALY rate of 268 per 100 000 [244-294] followed by squamous cell carcinoma (66 per 100 000 [45-94]) and thermal burns (61 per 100 000 [46-82]). Age-standardized incidence rates were highest for cellulitis (2654 per 100 000 [2502-2812]). Breast cancer had the highest age-standardized cost of care of all plastic surgery related diseases, at $5.1 billion, approximately half of the total age-standardized cost of $10.6 billion for included plastic surgery diseases. Conclusion: Plastic and reconstructive surgery related diseases, particularly breast cancer, thermal burns, and malignant melanoma, are responsible for a high burden of disease and significant cost to the Canadian healthcare system. These results will help guide national healthcare policy and should provide support to directing funding and research efforts toward impactful diseases facing the Canadian healthcare system.

Photoprotection by clothing: A review

Clothing is recognized by leading health agencies as a primary method to protect against the harmful effects of photodamage caused by ultraviolet (UV) radiation and visible light. The photoprotective capacity of clothing is commonly measured as the ultraviolet protective factor (UPF). While the technology driving photoprotective clothing has been well-established, there continues to be efforts to discover new materials to improve the UPF of clothing. Here, we show increased Google searches for photoprotective clothing over the last decade, suggesting a high level of public interest in photoprotective clothing. In addition, we investigate the frequency of UPF-graded photoprotective clothing sold by large retail stores featured in Fortune 1000. We review factors that alter the UPF of clothing and describe emerging textile technologies used to increase clothing's photoprotective capacity. Finally, we compare how photoprotective clothing is regulated among different countries, the importance of photoprotective clothing in occupational health, and research in visible light and clothing photoprotection.

Sun Protection Use at Work and Leisure by Outdoor Workers in Alberta, Canada

OBJECTIVE

To assess the prevalence and determinants of sun protection behaviours among outdoors workers at work and leisure in Alberta, Canada.

METHODS

We collected outdoor workers' demographics, skin cancer risk factors, job information, and sun habits at work and leisure using self-completed questionnaires. For both settings, we compared use of specific behaviours and modelled determinants of sun protection behaviour scores.

RESULTS

At work, wearing a sleeved shirt (81% often/always) and hat (73%) were most prevalent, while seeking shade (12%) and applying sunscreen (36%) were least prevalent. Workers had higher sun protection scores at work than leisure. Hours spent outdoors was a strong determinant for both models. Additional leisure model predictors were eye colour, sex, skin type, and job group.

CONCLUSIONS

Differences in behaviours across settings were observed and should be considered when developing solar UVR exposure reduction initiatives.

Solar ultraviolet radiation exposure among outdoor workers in Alberta, Canada

BACKGROUND

Outdoor workers are at risk of prolonged and high solar ultraviolet radiation (UVR) exposure, which is known to cause skin cancer. The objectives of this study were to characterize the UVR exposure levels of outdoor workers in Alberta, Canada, and to investigate what factors may contribute to their exposure.

METHODS

This study collected objective solar UVR measurements from outdoor workers primarily in Alberta during the summer of 2019. Workers were recruited via the management or health and safety teams from building trade unions and employers. Calibrated, electronic UVR dosimeters were worn by workers on their hardhats, wrists, or lapels for five working days. Data on workers' demographics, jobs, sun protection behaviors, and personal risk factors were collected using questionnaires, and meteorological data for each sampling day were noted. Mean daily exposure measured as the standard erythemal dose (SED) was calculated and compared to the international occupational exposure limit guideline (1.3 SED). Marginal models were developed to evaluate potential determinants of occupational solar UVR exposure.

RESULTS

In total, 883 measurements were collected from 179 workers. On average, workerswere exposed to 1.93 SED (range: 0.03-16.63 SED) per day. Just under half of workers (45%) were exposed to levels exceeding the international exposure limit guideline. In the bivariate analyses, landscape and maintenance workers, as well as trade and recreation workers, had the highest levels of exposure (average: 2.64 and 1.84 SED, respectively). Regional variations were observed, with the "other" cities/regions (outside of Edmonton and Calgary) experiencing the highest average levels (2.60 SED). Workers who placed the dosimeters on their hardhats experienced higher levels compared to the other groups. Exposure was highest on sunny and mixed days. Education, trade, city, dosimeter placement, forecast, hair colour, and number of hours outside were included in the final exposure model, of which trade, dosimeter placement, forecast, and number of hours outside at work were statistically significant.

CONCLUSIONS

Exposure to elevated solar UVR levels is common among outdoor workers in Alberta. The study findings can help inform future monitoring studies and exposure reduction initiatives aimed at protecting workers.

Canadian Burden of Skin Disease From 1990 to 2017: Results From the Global Burden of Disease 2017 Study [Formula: see text]

Background

Skin diseases can have high morbidity that can be costly to society and individuals. To date, there has been no comprehensive assessment of the burden of skin disease in Canada.

Objectives

To evaluate the burden of 18 skin and subcutaneous diseases from 1990 to 2017 in Canada using the Global Burden of Disease (GBD) data.

Methods

The 2017 GBD study measures health loss from 359 diseases and injuries in 195 countries; we evaluated trends in population health in Canada from 1990 to 2017 using incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life years (DALYs). Data are presented as rates (per 100 000), counts, or percent change with the uncertainty interval in brackets.

Results

From 1990 to 2017 for all skin diseases, DALY rates increased by 8% to 971 per 100 000 (674-1319), YLD rates increased by 8% to 897 per 100 000 (616-1235), YLL rates increased by 4% to 74 per 100 000 (53-89), and death rates increased by 18% to 5 per 100 000 (3-6). DALY rates for melanoma increased by 2% to 54 per 100 000 (39-68), for keratinocyte carcinoma by 14% to 17 per 100 000 (16-19), and for skin and subcutaneous disease by 8% to 900 per 100 000 (619-1233). The observed over expected ratios were higher for skin and subcutaneous disease (1.37) and keratinocyte carcinoma (1.17) and were lower for melanoma (0.73).

Conclusions

The burden of skin disease has increased in Canada since 1990. These results can be used to guide health policy regarding skin disease in Canada.

Senior managers' awareness of sun protection policy predicts implementation of worksite sun safety in a randomized trial

BACKGROUND

Outdoor workers experience chronic exposure to harmful ultraviolet radiation (UV) elevating their risk for skin cancer.

METHODS

A controlled randomized trial promoted the adoption of workplace sun safety policy and employee education at 98 public organizations in Colorado. A 2-year follow-up study with 68 organizations assessed the association of senior manager awareness of sun safety policies and implementation of sun safety actions.

RESULTS

Senior managers' awareness of existing sun safety policies, but not their personal sun protection behaviors, predicted implementation of sun safety actions including the number of sun protection messages and sun protection items in the workplace and increased communication about sun safety to employees.

CONCLUSIONS

Organizational adoption of sun safety policy must include efforts to broadly inform a workplace's senior management to ensure the policies are actually implemented and provide support for sun protection behaviors by outdoor workers to reduce UV exposure and skin cancer risk.

Solar Ultraviolet Radiation Exposure among Outdoor Workers in Three Canadian Provinces

Introduction

Solar ultraviolet radiation (UVR) exposure places outdoor workers at risk of skin cancer and exposure is difficult to control. In response, the Sun Safety at Work Canada (SSAWC) project was undertaken (2014–2016). The purpose of this substudy was to characterize the UVR exposure levels of outdoor workers in the SSAWC project.

Methods

Thirteen workplaces in the provinces of British Columbia, Ontario, and Nova Scotia participated in an exposure monitoring campaign (late summer/early fall 2016). Study participants were workers from power utilities and municipalities. Participants wore a UVR measurement badge (light-sensitive polysulfone plastic) on their wrist, shoulder, or hardhat. Badge calibration and absorbance measurements were performed in the AusSun Research Lab. Personal UVR doses are presented as standard erythemal doses (SED) and compared with the internationally recommended exposure limit (1.3 SED), as well as to the total available UVR by date. Generalized linear models were used to examine determinants of solar UVR for personal UVR dose (for both SED and percent of ambient UVR). Models considered badge placement, date, province, industry, main job task, and the hours spent outdoors.

Results

Mean personal UVR dose of participating workers was 6.1 SED (nearly 5× the recommended limit). Just 14% of workers experienced ‘acceptable’ levels of solar radiation; 10% were exposed at >10 times the limit. In univariate analyses, workers in Ontario had the highest levels (mean 7.3 SED), but even in the lowest exposed province (British Columbia), the mean personal UVR dose was 4.5 SED. Utility workers had double the exposure of municipal workers (10.4 and 5.5 SED, respectively). In the determinants of exposure models, the differences by province were muted, but utility line workers and those in general maintenance had higher predicted exposures. Those who wore their badge on their hardhat also had higher values of SED in the fully adjusted determinants models.

Conclusions

Solar ultraviolet overexposure among outdoor workers is a concern, even in a country like Canada with relatively low ambient UVR. Implementation of sun safety programs should be supported in an effort to reduce exposure in this vulnerable group of workers.

Implementation of Occupational Sun Safety at a 2-Year Follow-Up in a Randomized Trial: Comparison of Sun Safe Workplaces Policy Intervention to Attention Control

PURPOSE

Implementation of employer sun safety actions was assessed in a 2-year follow-up to an occupational sun protection policy intervention.

DESIGN

Two-year follow-up assessment in a randomized pretest-posttest controlled design.

SETTING

Local government organizations with workers in public safety, public works, and parks and recreation.

PARTICIPANTS

Sixty-three local government organizations (participation = 64%) and 330 frontline supervisors and 1454 workers.

INTERVENTION

Sun Safe Workplaces (SSW) intervention promoting occupational sun safety policy and education.

MEASURES

Observations of SSW messages and sun safety items and surveys on organizations' communication and actions on sun safety.

ANALYSIS

Comparison between SSW and control groups was conducted using regression models and adjusted for clustering where appropriate, with α criterion set at P = .05 (2-tailed).

RESULTS

At intervention worksites, more SSW messages ( P < .001) and sun safety items ( P = .025) were observed; more frontline supervisors reported organizations provided free/reduced price sunscreen ( P = .005) and communicated about sun safety ( P < .001); and more workers recalled receiving sun safety messages ( P < .001) and sun safety training ( P <.001) compared to control organizations. Implementation was greater at larger than smaller intervention organizations for wide-brimmed hats ( P = .009), long work pants ( P = .017), and shade structures ( P = .036). Older workers received the most written messages ( P = .015).

CONCLUSIONS

Sun Safe Workplaces appeared to produce actions by organizations to support employee sun safety. Large organizations may have processes, communication channels, and slack resources to achieve more implementation.

Estimating National-Level Exposure to Antineoplastic Agents in the Workplace: CAREX Canada Findings and Future Research Needs

OBJECTIVES

Occupational exposure to antineoplastic agents occurs in various environments and is associated with increased cancer risk and adverse reproductive outcomes. National-level information describing the location and extent of occupational exposure to antineoplastic agents is unavailable in Canada and most other countries. CAREX Canada aimed to estimate the prevalence and relative levels of occupational exposures to antineoplastic agents across work setting, occupation, and sex.

METHODS

'Exposure' was defined as any potential for worker contact with antineoplastic agents. Baseline numbers of licensed workers were obtained from their respective professional bodies. For unlicensed workers, Census data or data extrapolated from human resources reports (e.g., staffing ratios) were used. Prevalence was estimated by combining population estimates with exposure proportions from peer-reviewed and grey literature. Exposure levels (classified as low, moderate, and high) by occupation and work setting were estimated qualitatively by combining estimates of contact frequency and exposure control practices.

RESULTS

Approximately 75000 Canadians (0.42% of the total workforce) are estimated as occupationally exposed to antineoplastic agents; over 75% are female. The largest occupational group exposed to antineoplastic agents is community pharmacy workers, with 30200 exposed. By work setting, 39000 workers (52% of all exposed) are located in non-hospital settings; the remaining 48% are exposed in hospitals. The majority (75%) of workers are in the moderate exposure category.

CONCLUSIONS

These estimates of the prevalence and location of occupational exposures to antineoplastic agents could be used to identify high-risk groups, estimate disease burden, and target new research and prevention activities. The limited secondary data available for developing these estimates highlights the need for increased quantitative measurement and documentation of antineoplastic agent contamination and exposure, particularly in work environments where use is emerging.

Occupational exposure to solar ultraviolet radiation and the risk of prostate cancer

OBJECTIVES

Preventable risk factors for prostate cancer are poorly understood; sun exposure is a possible protective factor. The goal of this study was to investigate prostate cancer risk in outdoor workers, a population with high sun exposure.

METHODS

Prostate cancer cases and controls from a large study (conducted between 1994 and 1997) were used for this analysis. A job exposure matrix (JEM) was used to assign solar ultraviolet radiation (UVR) at work as moderate (2 to <6 hours outside/day) or high (≥6 hours). Average daily satellite UV-B measures were linked to the latitude/longitude of the residences of each participant. Several other exposure metrics were also examined, including ever/never exposed and standard erythemal dose by years (SED×years). Logistic regression was used to evaluate the association between solar UVR exposure and the odds of prostate cancer.

RESULTS

A total of 1638 cases and 1697 controls were included. Men of Indian and Asian descent had reduced odds of prostate cancer (ORs 0.17 (0.08 to 0.35) and 0.25 (0.15 to 0.41), respectively) compared with Caucasian men, as did single men (OR 0.76 (0.58 to 0.98)) compared with married men. Overall, no statistically significant associations were observed between sun exposure and prostate cancer with 1 exception. In the satellite-enhanced JEM that considered exposure in high category jobs only, prostate cancer odds in the highest quartile of cumulative exposure was decreased compared with unexposed men (OR 0.68 (0.51 to 0.92)).

CONCLUSIONS

This study found limited evidence for an association with prostate cancer, with the exception of 1 statistically significant finding of a decreased risk among workers with the longest term and highest sun exposure.

Levels of Occupational Exposure to Solar Ultraviolet Radiation in Vancouver, Canada

INTRODUCTION

Outdoor workers are at high risk of exposure to solar ultraviolet radiation (UVR), a known human carcinogen. In Canada, no objective measures of UVR exposure are available for occupational settings.

METHODS

The Outdoor Workers Project collected UVR exposure data among outdoor workers in Vancouver, Canada during the summer of 2013. Objective measures of exposure were taken for one week using calibrated electronic UVR dosimeters. Additional data was collected from workers on skin cancer risk factors, family history of skin cancer, and job type; as well as meteorological data for sampling days. Marginal models were constructed to examine the worker, job and meteorological determinants of UVR exposure levels, as measured in standard erythemal dose (SED).

RESULTS

Seventy-eight workers were recruited, of which 73 had at least 1 day of measured UVR exposure for this analysis. Participants were mostly male, young and Caucasian. Mean exposure (corrected for repeated measures) was 1.08 SED. Exposure measures were highly variable even in the same workplace, ranging from 0.01 SED to 19.2 SED. Younger age, working in land-based construction, and sunnier weather forecasts led to higher levels of UVR exposure.

CONCLUSIONS

Exposure levels capable of causing sunburn were common in this study of outdoor workers, in a location not typically associated with high sun exposure.

Outdoor Workers' Use of Sun Protection at Work and Leisure

Background

Outdoor workers are at risk of high ultraviolet radiation exposure, and may have difficulty using sun protection. The objectives were to determine the prevalence of sun protection behaviors in a sample of outdoor construction workers, and to assess which factors predict better sun protection practices.

Methods

Participants were recruited via construction unions. Workers answered a questionnaire on demographics, skin cancer risk, sun protection behaviors, and job. Sun protection behavior scores (from questions on sunscreen use, sleeved shirt, hat, shade seeking, sunglasses) were calculated by converting Likert-scale answers to scores from 0 to 4, and taking the mean (separately for work and leisure). Determinants of sun protection behavior scores were examined for work and leisure using generalized linear models.

Results

Seventy-seven workers had complete questionnaire data (participation 98%). Sun protection behaviors used most often were hats (79% often/always) and sleeved shirts (82% often/always); least prevalent were shade-seeking (8% often/always) and sunscreen (29% often/always). For both work and leisure scores, the strongest predictor was skin type, with fairer-skinned individuals having higher sun protection behavior scores. Workers had higher scores at work than on weekends. Workplaces that required hats and sleeved shirts for safety purposes had higher protection behavior scores.

Conclusion

This high-participation rate cohort helps characterize sun protection behaviors among outdoor workers. Workers practiced better sun protection at work than on weekends, suggesting that workplace policies supportive of sun protection could be useful for skin cancer prevention in the construction industry.

The Sustainability of an Occupational Skin Cancer Prevention Program

OBJECTIVE

Sustainability of prevention programs is a public health goal.

METHODS

The effectiveness of Go Sun Smart, an occupational skin cancer prevention program, was evaluated 5 to 7 years out from the conclusion of a controlled randomized dissemination trial that compared an enhanced versus basic dissemination strategy at 53 ski areas enrolled in the trial.

RESULTS

Employees (n = 2940) at ski areas in the enhanced condition reported fewer sunburns but did not differ from employees in the basic condition on other sun-protection measures. Significant differences for all sun-protection practices were identified at ski areas that displayed nine or more Go Sun Smart materials or a combined total of nine or more Go Sun Smart and other sun safety messages.

CONCLUSIONS

Exposure to prevention messages is an important determinant of program effectiveness and potentially of program sustainability.

Skin cancer in rural workers: nursing knowledge and intervention

OBJECTIVETo identify the exposure of rural workers to the sun's ultraviolet radiation and pesticides; to identify previous cases of skin cancer; and to implement clinical and communicative nursing actions among rural workers with a previous diagnosis of skin cancer.METHODObservational-exploratory study conducted with rural workers exposed to ultraviolet radiation and pesticides in a rural area in the extreme south of Brazil. A clinical judgment and risk communication model properly adapted was used to develop interventions among workers with a previous history of skin cancer.RESULTSA total of 123 (97.7%) workers were identified under conditions of exposure to the sun's ultraviolet radiation and pesticides; seven (5.4%) were identified with a previous diagnosis of skin cancer; four (57.1%) of these presented potential skin cancer lesions.CONCLUSIONThis study's results enabled clarifying the combination of clinical knowledge and risk communication regarding skin cancer to rural workers.

Sun Safety at Work Canada: a multiple case-study protocol to develop sun safety and heat protection programs and policies for outdoor workers

BACKGROUND

CAREX Canada has identified solar ultraviolet radiation (UV) as the second most prominent carcinogenic exposure in Canada, and over 75 % of Canadian outdoor workers fall within the highest exposure category. Heat stress also presents an important public health issue, particularly for outdoor workers. The most serious form of heat stress is heat stroke, which can cause irreversible damage to the heart, lungs, kidneys, and liver. Although the need for sun and heat protection has been identified, there is no Canada-wide heat and sun safety program for outdoor workers. Further, no prevention programs have addressed both skin cancer prevention and heat stress in an integrated approach. The aim of this partnered study is to evaluate whether a multi-implementation, multi-evaluation approach can help develop sustainable workplace-specific programs, policies, and procedures to increase the use of UV safety and heat protection.

METHODS/DESIGN

This 2-year study is a theory-driven, multi-site, non-randomized study design with a cross-case analysis of 13 workplaces across four provinces in Canada. The first phase of the study includes the development of workplace-specific programs with the support of the intensive engagement of knowledge brokers. There will be a three-points-in-time evaluation with process and impact components involving the occupational health and safety (OHS) director, management, and workers with the goal of measuring changes in workplace policies, procedures, and practices. It will use mixed methods involving semi-structured key informant interviews, focus groups, surveys, site observations, and UV dosimetry assessment. Using the findings from phase I, in phase 2, a web-based, interactive, intervention planning tool for workplaces will be developed, as will the intensive engagement of intermediaries such as industry decision-makers to link to policymakers about the importance of heat and sun safety for outdoor workers.

DISCUSSION

Solar UV and heat are both health and safety hazards. Using an occupational health and safety risk assessment and control framework, Sun Safety at Work Canada will support workplaces to assess their exposure risks, implement control strategies that build on their existing programs, and embed the controls into their existing occupational health and safety system.

Occupational exposure to solar radiation in Australia: who is exposed and what protection do they use?

OBJECTIVE

Solar ultraviolet radiation (UVR) exposure is widely recognised as a leading cause of skin cancer, with outdoor workers being particularly at risk. Little is known on a national level about how many workers are exposed to solar radiation, the circumstances in which they are exposed, or their use of protective measures.

METHODS

The Australian Work Exposures Study (AWES) was a cross-sectional telephone survey of 5,023 Australian workers aged 18 to 65. A subset of 1,113 respondents who indicated they worked outdoors was asked about their exposure to solar radiation in terms of the amount of time they spent working outdoors, their working location and their use of sun protective measures.

RESULTS

A total of 1,100 respondents (22% overall) were assessed as being exposed to solar radiation at work. Exposure was more likely among males and those residing in lower socioeconomic and regional areas. Sun protection was used by 95% of the respondents, although the level of protection varied among workers, with only 8.7% classified as fully protected.

CONCLUSIONS

This study provides valuable information regarding solar exposure that has not previously been available.

IMPLICATIONS

The results of this study will inform strategies for risk reduction.

Sunlight exposure during leisure activities and risk of prostate cancer in Montréal, Canada, 2005-2009

Background

Prostate cancer (PCa) is the leading cause of cancer in men in many developed countries, but no modifiable risk factors have been identified. A handful of analytical studies have suggested a possible etiological role for sunlight exposure. We report here on the association between leisure-time sunlight exposure during adulthood and PCa risk in the context of a population-based case–control study.

Methods

In all, 1,904 PCa cases were ascertained across Montreal French hospitals between 2005 and 2009. Concurrently, 1,962 population controls, frequency matched to cases by age (±5 years), were selected from the electoral list for French-speakers in Greater Montreal. Interviews elicited the frequency of engagement in any leisure activity during adulthood. This was used to derive cumulative sunlight exposure indices: a cumulative number of leisure activities events entailing sunlight exposure and a cumulative duration of sunlight exposure during leisure activities. Unconditional logistic regression was conducted to yield odds ratios (OR) and 95% confidence intervals (CI) for estimating the association between sunlight exposure indices and PCa risk, adjusting for age, ancestry, family history of PCa, PCa screening, education, solar protection, body mass index and physical activity.

Results

Compared with men in the upper quartile category for the number of sunlight exposure events, men never exposed during leisure time had an OR of 1.32 (95% CI: 0.82-2.14). ORs were 1.11, 0.91 and 1.00 for the first to the third quartiles of exposure, respectively. Similar results were observed for cumulative duration of exposure to sunlight, and by PCa aggressiveness.

Conclusion

These findings provide little evidence of an association between sunlight exposure during leisure-time and PCa risk. Men with no sunlight exposure appeared at somewhat higher risks but none of the estimates achieved statistical significance.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-756) contains supplementary material, which is available to authorized users.

CAREX Canada: an enhanced model for assessing occupational carcinogen exposure

OBJECTIVES

To estimate the numbers of workers exposed to known and suspected occupational carcinogens in Canada, building on the methods of CARcinogen EXposure (CAREX) projects in the European Union (EU).

METHODS

CAREX Canada consists of estimates of the prevalence and level of exposure to occupational carcinogens. CAREX Canada includes occupational agents evaluated by the International Agency for Research on Cancer as known, probable or possible human carcinogens that were present and feasible to assess in Canadian workplaces. A Canadian Workplace Exposure Database was established to identify the potential for exposure in particular industries and occupations, and to create exposure level estimates among priority agents, where possible. CAREX EU data were reviewed for relevance to the Canadian context and the proportion of workers likely to be exposed by industry and occupation in Canada was assigned using expert assessment and agreement by a minimum of two occupational hygienists. These proportions were used to generate prevalence estimates by linkage with the Census of Population for 2006, and these estimates are available by industry, occupation, sex and province.

RESULTS

CAREX Canada estimated the number of workers exposed to 44 known, probable and suspected carcinogens. Estimates of levels of exposure were further developed for 18 priority agents. Common exposures included night shift work (1.9 million exposed), solar ultraviolet radiation exposure (1.5 million exposed) and diesel engine exhaust (781 000 exposed).

CONCLUSIONS

A substantial proportion of Canadian workers are exposed to known and suspected carcinogens at work.

Estimating occupational exposure to carcinogens in Quebec

BACKGROUND

We estimated the extent of exposure to occupational carcinogens in Quebec, Canada, to help raise awareness of occupational cancers.

METHODS

Proportions of workers exposed to 21 recognized and 17 probable carcinogens (according to Quebec occupational health regulation and the International Agency for Research on Cancer [IARC] classification) were extracted from various sources: workplace monitoring data, research projects, a population survey, radiation protection data, exposure estimates from the Carcinogen Exposure Canada (CAREX Canada) Project database, and published exposure data. These proportions were applied to Quebec labor force data.

RESULTS

Among the 38 studied, carcinogens with the largest proportions of exposed workers were solar radiation (6.6% of workers), night shift work/rotating shift work including nights (6.0%), diesel exhaust fumes (4.4%), wood dust (2.9%) and polycyclic aromatic hydrocarbons (2.0%). More than 15 carcinogens were identified in several industrial sectors, and up to 100,000 young workers are employed in these sectors.

CONCLUSION

Although crude, estimates obtained with different data sources allow identification of research and intervention priorities for cancer in Quebec.