Anne-Marie Nicol

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.

Occupational Exposures to Antineoplastic Drugs and Ionizing Radiation in Canadian Veterinary Settings: Findings From a National Surveillance Project

ObjectivesAlthough veterinary workers may encounter various occupational health hazards, a national characterization of exposures is lacking in Canada. This study used secondary data sources to identify veterinary exposure prevalence for ionizing radiation and antineoplastic agents, as part of a national surveillance project.MethodsFor ionizing radiation, data from the Radiation Protection Bureau of Health Canada were used to identify veterinarians and veterinary technicians monitored in 2006. This was combined with Census statistics to estimate a prevalence range and dose levels. For antineoplastic agents, exposure prevalence was estimated using statistics on employment by practice type and antineoplastic agent usage rates, obtained from veterinary licensing bodies and peer-reviewed literature.ResultsIn 2006, 7,013 (37% of all) Canadian veterinary workers were monitored for ionizing radiation exposure. An estimated 3.3% to 8.2% of all veterinarians and 2.4% to 7.2% of veterinary technicians were exposed to an annual ionizing radiation dose above 0.1 mSv, representing a total of between 536 and 1,450 workers. All monitored doses were below regulatory limits. For antineoplastic agents, exposure was predicted in up to 5,300 (23%) of all veterinary workers, with an estimated prevalence range of 22% to 24% of veterinarians and 20% to 21% of veterinary technicians.ConclusionThis is the first national-level assessment of exposure to ionizing radiation and antineoplastic agents in Canadian veterinary settings. These hazards may pose considerable health risks. Exposures appeared to be low, however our estimates should be validated with comprehensive exposure monitoring and examination of determinants across practice areas, occupations, and tasks.RésuméObjectifsBien que les agents vétérinaires puissent être exposés à divers dangers pour la santé au travail, il manque au Canada une caractérisation nationale de ce type d’exposition. Dans le cadre d’un projet de surveillance national, nous avons utilisé des sources de données secondaires pour cerner la prévalence des expositions aux rayonnements ionisants et aux antinéoplasiques en milieu vétérinaire.MéthodePour les rayonnements ionisants, les données du Bureau de la radioprotection de Santé Canada ont servi à identifier les vétérinaires et les techniciens vétérinaires surveillés en 2006. Nous avons combiné ces données aux chiffres du Recensement pour estimer un intervalle de prévalence et des niveaux de dose. Pour les antinéoplasiques, la prévalence de l’exposition a été estimée à l’aide des statistiques sur l’emploi par type de pratique et des taux d’utilisation des antinéoplasiques, lesquels ont été obtenus dans les revues évaluées par les pairs et auprès des organismes de réglementation de la profession vétérinaire.RésultatsEn 2006, 7 013 (37%) des agents vétérinaires canadiens ont été surveillés pour leur exposition aux rayonnements ionisants. On estime qu’entre 3,3% et 8,2% des médecins vétérinaires et entre 2,4% et 7,2% des techniciens vétérinaires ont été exposés à une dose annuelle de rayonnements ionisants supérieure à 0,1 mSv, soit entre 536 et 1 450 personnes en tout. Toutes les doses surveillées étaient en deçà des limites réglementaires. Pour les antinéoplasiques, une exposition était prévisible chez jusqu’à 5 300 agents vétérinaires (soit 23%), avec un intervalle de prévalence estimatif de 22% à 24% des médecins vétérinaires et de 20% à 21% des techniciens vétérinaires.ConclusionIl s’agit de la première évaluation nationale de l’exposition aux rayonnements ionisants et aux antinéoplasiques en milieu vétérinaire au Canada. Ces dangers peuvent poser des risques considérables pour la santé. Les niveaux d’exposition semblent être faibles, mais nos estimations devraient être validées par une surveillance complète de l’exposition et par un examen des déterminants selon la sphère de pratique, la profession et la tâche.

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 <6u2005hours outside/day) or high (≥6u2005hours). 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

INTRODUCTIONnOutdoor 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.nnnMETHODSnThe 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).nnnRESULTSnSeventy-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.nnnCONCLUSIONSnExposure levels capable of causing sunburn were common in this study of outdoor workers, in a location not typically associated with high sun exposure.

Burden of lung cancer attributable to occupational diesel engine exhaust exposure in Canada

Objective To estimate the population attributable fraction (PAF) and number of incident and fatal lung cancers in Canada from occupational exposure to diesel engine exhaust (DEE). Methods DEE exposure prevalence and level estimates were used with Canadian Census and Labour Force Survey data to model the exposed population across the risk exposure period (REP, 1961–2001). Relative risks of lung cancer were calculated based on a meta-regression selected from the literature. PAFs were calculated using Levin’s equation and applied to the 2011 lung cancer statistics obtained from the Canadian Cancer Registry. Results We estimated that 2.4% (95% CI 1.6% to 6.6%) of lung cancers in Canada are attributable to occupational DEE exposure, corresponding to approximately 560 (95% CI 380 to 1570) incident and 460 (95% CI 310 to 1270) fatal lung cancers in 2011. Overall, 1.6u2009million individuals alive in 2011 were occupationally exposed to DEE during the REP, 97% of whom were male. Occupations with the highest burden were underground miners, truck drivers and mechanics. Half of the attributable lung cancers occurred among workers with low exposure. Conclusions This is the first study to quantify the burden of lung cancer attributable to occupational DEE exposure in Canada. Our results underscore a large potential for prevention, and a large public health impact from occupational exposure to low levels of DEE.

S10-2 Carex canada: innovations and applications

Ten years ago the CAREX Canada project was initiated with the objective of identifying how many Canadians are exposed to workplace and environmental carcinogens as well as how and where they are exposed. While the occupational component of the project was largely based on the European CAREX project, CAREX Canada sought to incorporate a number of innovations based on the Finnish job exposure matrix (FinJEM), other CAREX projects such as Costa Rica’s, and large exposure database projects that were being initiated at the time. CAREX Canada sought to enhance the original CAREX model in two major ways. First, prevalence of exposure was assessed based on both industry (328 categories) and occupation (520 categories), using much finer groups than previous projects. This allowed for both better assessment of exposure and a finer level of reporting for targeting prevention efforts. Second, where possible, levels of exposure were estimated as three categories of low, medium, and high using cut-points based on occupational exposure limits. To facilitate this classification, the Canadian Workplace Exposure Database was created, using several hundred thousand measurements acquired from regulatory agencies. For example, we estimated that 380,000 workers are exposed to crystalline silica, 14% high (>0.025 mg/m3), 39% moderate (0.0125–0.025 mg/m3), and 47% low. These enhancements have made CAREX Canada a much more effective tool for use in both prevention and, through creation of job exposure matrixes, epidemiologic applications. The greater granularity of the prevalence estimates and the availability of measured exposure levels for many common carcinogens have facilitated the use of this data for cancer surveillance and burden of cancer projects. Level of exposure estimation has been particularly useful, but has been limited to what can be called the “data-rich” exposures. This project has also provided a systematic means of identifying where significant data gaps exist.

0211 Solar ultraviolet radiation (UVR) exposure levels and sun protection behaviours in outdoor workers in British Columbia, Canada

Objectives The goal of this study was to measure outdoor workers’ exposure to solar UVR in a Canadian setting, and to examine their sun protection behaviours at work and leisure. Method Participants were recruited via trade unions and companies with outdoor operations. Workers wore an electronic dosimeter that measured UVR intensity once/minute for 5 working days and completed a questionnaire on skin cancer risk factors, sun protection behaviours, and job characteristics. Dosimeter data was converted to UVIndex and Standard Erythemal Dose (SED), an indicator for the potential for sunburn. Results Seventy-eight outdoor workers were recruited. The workers were largely male (95%), with a mean age of 38 years. Workers that reported the most outdoor working hours had the highest measured UVR exposure (mean SED of 2.6, >8 times the level of those reporting ≥1 outdoor hour). Workers who reported the most outdoor hours at work also reported the most outdoor hours at leisure. Over 70% of workers reported using sleeved shirts, hats, and sunglasses at work ‘often or always’. Sunscreen and shade-seeking were low, with 29% and 8% reporting these behaviours at work, respectively. Despite reasonable protective behaviours, 70% of workers reported ≥1 sunburn last summer; this climbed to 80% among those who worked outside all day. Conclusions Outdoor workers in Canada are at risk of high solar UVR exposure during the summer. They participate selectively in sun protective behaviours, opting more often for clothing protection than sunscreen or shade protection. Most experience acute damage from exposure (i.e. sunburn) despite attempting to protect themselves.

0402 Incorporating more detailed exposure assessment with quantitative estimates is assessing the burden of occupational cancer

Objectives In recent years, several new burden projects have been initiated with increased methodological sophistication. Previous studies have varied with respect to methods used to identify the prevalence and relevant levels of exposure, but many have relied on CAREX estimates. In this presentation, we will focus on the impact of incorporating more detailed exposure assessments with quantitative estimates as part of the Canadian burden of cancer project. Method The Canadian exposure estimation process relies on data from CAREX Canada, taking into account industry and occupation at a more detailed level than previously. For many common carcinogens, the Canadian Workplace Exposure Database is used to account for changes in exposure levels over time and quantitative exposure-response relationships from the literature are used to assign relative risks relevant to the mean level of each exposure group. Historical employment trends are based upon census data at multiple time-points with province, sex, industry, and occupation detail. Results Developing estimates for approximately 300 industries, as well as by occupation, and the need for estimating the age and gender characteristics of predicted cases to estimate economic burden, has also increased the complexity of estimating historic labour force dynamics. Annual labour force data 1976–2010 is used to attribute age- and tenure-distribution characteristics by province, sex, and industry. Conclusions Although our main objective was to increase the validity of the burden estimation process, the more detailed exposure estimates allow us to calculated cancer burden for much more specific industry sectors and occupations, allowing for detailed risk reduction strategies.