Workers Health & Safety Centre

Occupational cancer prevention in Ontario focus of groundbreaking new report

Burden of Occupational Cancer in Ontario
Bold, collaborative actions by legislators and employers alike are urgently needed to prevent thousands of estimated occupational cancers every year in Ontario, says a new report.

The burden of occupational cancer is “substantial and often overlooked” and also “largely preventable,” the report concludes. As such, the report’s evidence-based recommendations are wide-sweeping and directed to all levels of government, suggesting, among other things, greater provincial inter-ministerial collaboration and closer cooperation with federal counterparts. 

The report, Burden of Occupational Cancer in Ontario: Major workplace carcinogens and prevention of exposure , was jointly produced by the Occupational Cancer Research Centre (OCRC) and Cancer Care Ontario's (CCO) Population Health and Prevention team with input from experts on scientific content and policy recommendations. This latest occupational cancer research was funded by the Canadian Cancer Society and is part of a larger four-year national project. CAREX Canada provided occupational carcinogen exposure estimates.

Recommendations for prevention—a blueprint for action

This important report expands the knowledge and practice of documenting exposures to carcinogens, but its authors also see it as a “tremendous opportunity” to support decision-makers in developing a robust occupational cancer prevention plan for Ontario.

By identifying major policy gaps, the report highlights opportunities which could significantly reduce the burden of cancer. Dr. Paul Demers, OCRC director, said of the report’s release, “I can’t count the number of times that I have talked about how important it is to prevent exposure to carcinogens, but raising awareness doesn’t always lead to action. I think the numbers are important to make this real and push action towards preventing exposure to these causes of cancer.”

Key overarching policy recommendations include:
  • Strengthening and updating occupational exposure limits (OEL’s) to reflect evidence of health effects and be at least as protective as those set by the American Conference of Governmental Industrial Hygienists – specifically, adopting new health-based OEL’s for chromium (VI) compounds, nickel compounds, formaldehyde and wood dust.
  • Amending Ontario’s Toxics Reduction Act to specifically address worker exposure and health issues, expand the number of substances covered under the Act, and provide support to workplaces through a government-funded institution like the Toxics Use Reduction Institute in Massachusetts.
  • Establishing public, free workplace exposure registries and exposure surveillance systems that are readily accessible to employers, workers and the public
  • Expanding coverage of the Designated Substances Regulation to include construction project employers and workers. 
  • Vigorously enforcing all existing health and safety regulations.

Of note to health and safety advocates, the report recognizes the importance of involving workers and their representatives in workplace prevention efforts, specifically in the development of toxic use reduction plans.

Additionally, the report acknowledges a training standard for the workplace hazardous materials information system (WHMIS), one that could help ensure workers receive consistent, high-quality training. This is especially beneficial for those working with or exposed to carcinogens, but would also ensure a minimum level of instruction to Ontario workers, most of whom are covered by the WHMIS regulation. Worker advocates have long called for such reform.

Further, the report adopts a hierarchy of controls framework to examine exposure reduction. This approach prioritizes more protective controls, like elimination and substitution, over less effective controls such as personal protective equipment.
Specific report recommendations to reduce exposures to priority carcinogens include:
  • Mandating comprehensive workplace sun safety programs
  • Eliminating the use of arsenic-treated wood
  • Using high pressure water instead of silica in sand-blasting operations
  • Upgrading and replacing diesel engines
  • Regulating mandatory ventilation for welding fumes
  • Enforcing smoke-free workplace legislation (a 2012 report found 28 % of Ontario workers reported being exposed to environmental tobacco smoke despite a smoke-free workplaces law)
  • Developing an explicit and specified regulation for radon.

Ontario’s occupational cancer burden—the need for prevention now

Until this report, little research had been done to quantify the contribution of workplace exposures to the burden of cancer despite the fact Ontarians spend about one-third of their waking hours at work. Researchers were also challenged by a lack of reliable, routine collection of data on exposure to workplace carcinogens. 

The report studied 44 known and suspected carcinogens and 27 related cancer sites. Researchers prioritized and developed profiles for eleven of the most common carcinogens in Ontario workplaces. Seven of these included: welding fumes; nickel compounds; environmental tobacco smoke at work; radon; chromium (VI); arsenic; and benzene. Four carcinogens were found to have the largest estimated impact on cancer burden and also the highest number of Ontario workers exposed. These included:
  • Solar Radiation: About 450,000 Ontario workers are exposed, causing an estimated 1,400 non-melanoma skin cancer cases per year.
  • Asbestos: Some 55,000 workers are exposed, estimated to cause 630 lung cancers, 140 mesotheliomas, 15 laryngeal cancers and less than five ovarian cancers annually.
  • Diesel Engine Exhaust: About 301,000 workers are exposed every year accounting for 170 lung and 45 bladder cancer cases.
  • Crystalline Silica: Some 142,000 Ontario workers are exposed to crystalline silica, causing almost 200 lung cancer cases per year.

The report also identifies the burden of other known carcinogens of concern, including polycyclic aromatic hydrocarbons, artificial ultraviolet radiation, wood dust and formaldehyde. When it came to known or suspected emerging carcinogens, researchers highlighted exposures to antineoplastic agents, nanoparticles, pesticides and sedentary work. They particularly noted circadian-disrupting shift work, to which 833,000 workers are exposed and an estimated two to 5.2 per cent of all breast cancers in Ontario every year are probably associated.

For Dave Killham, Workers Health & Safety Centre executive director, the report provides a solid set of recommendations upon which to develop a blueprint for cancer prevention, and indeed prevention of occupational disease generally. “The burden of occupational cancer is so great we need a host of interventions from specific workplace solutions to substantial policy change,” says Killham. “Prevention of occupational disease demands more than raising awareness with a few fact sheets, tweets, and supposedly clever taglines. We need dramatic action now. Workers and their representatives have been saying as much for years. I am heartened to see others are saying the same thing, backing worker experiences of the workplace with much needed quality research and a practical plan focused on the real sources of worker suffering, the hazards, or in this case the carcinogens, themselves.”

Read related WHSC articles:
Canadians pay dearly for work-related asbestos exposure
CCO report includes new information on occupational cancers in Ontario
Regulation an important driver of workplace chemical substitution, report finds
Webinar highlights lack of cancer prevention in the U.K.

The Workers Health & Safety Centre assists workplace parties with training programs and information services aimed at raising awareness about hazardous exposures, including those which can contribute to the burden of cancer, and targeting prevention at the workplace level.

Call:       1-888-869-7950 and ask to speak with a training services representative