CAREX Canada: an enhanced model for assessing occupational carcinogen exposure

Abstract

ObjectivesTo 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).MethodsCAREX 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.ResultsCAREX 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).ConclusionsA substantial proportion of Canadian workers are exposed to known and suspected carcinogens at work.

Occupational carcinogen exposure in Canada

“…The work carried out by Peters et al 7 reported in this issue and that by others, for example Carey et al 12 in a previous issue in this journal, is therefore very important. There are clearly limitations to any approach that aims to develop such estimates, as acknowledged by Peters et al , and further efforts should be encouraged to improve the accuracy of the estimates and to track any temporal changes in the prevalence as well as intensity of exposure.…”

“…However, estimates provided by Peters et al 7 for Canada, as well as by Carey et al 12 for Australia and by us for Britain13 and the EU14 show that the prevalence of exposure to carcinogens is still high in certain industries, in particular for respirable crystalline silica, diesel exhaust fumes, ultraviolet radiation and shift work.…”

“…Driscoll et al 9 10 estimated that worldwide in 2000 there were 386 000 deaths from non-malignant respiratory disease and 152 000 cancer deaths from exposures experienced in the workplace. Other countries are currently doing similar studies, such as in Canada as reported by Peters et al ,7 while we are working on a project to estimate the burden of disease from occupational exposures in Singapore (see http://www.iom-world.sg/our-services/research/construct-healthsg/). …”

“…In this issue of the OEM , Peters et al 7 describe the CAREX—CANADA system. In addition to estimates of the prevalence of exposure, Peters and her coworkers have provided, where possible, estimates of the intensity of the exposure.…”

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

“…This evidence came mainly from workers in the railroad, trucking and mining industries, where the use of diesel engines is widespread. Millions of workers around the world are exposed to diesel exhaust,2 and in Canada, it is the most prevalent occupational lung carcinogen 3. Lung cancer is the most commonly diagnosed cancer as well as the leading cause of death from cancer in Canada,4 5 therefore the public health impact of occupational DEE exposure may be considerable.…”