by Kim Krisberg
Dr. Paul Demers says he frequently finds himself having to make the case for why studying workplace exposures to carcinogens is important. Oftentimes, he says, people believe such occupational dangers are a thing of the past.
"A lot of people are still developing cancer and dying from cancer due to workplace exposures, but only a small fraction of those are compensated, so people may think the magnitude of this problem is small," said Demers, director of the Occupational Cancer Research Centre in Ontario, Canada. "I wanted to have better data."
And in just a few years, he will. In November, Demers and his colleagues received funding from the Canadian Cancer Society to launch a study that's a first-of-its-kind for Canada and what Demers described as "a long time coming." The four-year, nationwide study will examine the human and economic impact of workplace exposures to carcinogens, focusing on 44 known or suspected carcinogens as identified by the World Health Organization's International Agency for Research on Cancer. The Canadian study will include a broad range of occupational settings, from mining and agriculture to the service and health care sectors.
"I couldn't say how many people were dying from benzene or formaldehyde or dozens of other carcinogens," Demers told me. "That's why I've wanted a comprehensive program for some time now...so we can assess, with a lot more rigorous data, the full impact of workplace carcinogens to raise awareness in government agencies, among employers, unions...as to why this continues to be an important area to pay attention to."
The first two years of the study will be spent pulling together relevant exposure and epidemiological data to develop a set of estimates on just how many cancers annually are due to occupational exposures. During the third year, as researchers wrap up the cancer estimates, a team of health economists will estimate both the direct and indirect costs of such occupational cancers, such medical costs, losses in productivity and the costs of disability. The last year of the study, Demers and his colleagues will work closely with the Canadian Cancer Society to "use the data as a lever to promote prevention programs in Canada — we plan to take the data we've generated and really push it out there so it gets in the hands of people who can push for more prevention," he said.
Demers told me his effort is modeled after a similar British effort that in 2010 released the report "The burden of occupational cancer in Great Britain." That report was the first to quantify the burden of occupational cancers in Great Britain, and Demers said its results and data will provide the Canadian effort with a good starting point. The British study found that more than 5 percent of the nation's cancer deaths were attributable to a person's occupation in 2005. Report authors found that:
Asbestos, shift work, mineral oils, solar radiation, silica, diesel engine exhaust, coal tars and pitches, occupation as a painter or welder, dioxins, environmental tobacco smoke, radon, tetrachloroethylene, arsenic and strong inorganic mists each contribute 100+ (cancer) registrations. Industries/occupations with high cancer registrations include construction, metalworking, personal/household services, mining, land transport, printing/publishing, retail/hotels/restaurants, public administration/defense, farming and several manufacturing sectors. 56% of cancer registrations in men are attributable to work in the construction industry (mainly mesotheliomas, lung, bladder and non-melanoma skin cancers) and 54% of cancer registrations in women are attributable to shift work (breast cancer).
Demers noted that his study won't be generating new data on cancer causation; instead, it will be a "synthesis of what we already know to get a much more comprehensive view of the impact." And while the study will be unique in its comprehensiveness of cancer data, the economic research seems especially promising in its ability to effect change.
"We want to communicate the problems of not addressing this issue both in terms of humans suffering, but also in terms of economic costs so that people realize that paying for prevention actually does pay off in the long run," he said.
Demers noted that the economic part of the study was very purposefully designed to increase the study's impact and will likely go further in its economic analysis than any other occupational study so far. Demers estimates that in Canada, around 5 percent of workplace-related cancer cases receive workers compensation, and those are mostly asbestos cases. His study, he says, could indeed have significant implications for the workers compensation system, which could be a good thing for prevention.
"Compensation is the stick that drives prevention," Demers said.
Demers says he hopes the results of the massive effort will be used by decision-makers at all levels of government when considering workplace regulations and enforcement and that the results will "change the consciousness of employers as well in terms of realizing the importance of this issue and the importance of spending on prevention." He's also hoping the work will raise the overall visibility of occupational cancer research in Canada.
"Occupational cancer doesn't get its due in cancer research, that's for sure" he said. "There's been a focus in cancer prevention on lifestyle factors — these are things under an individual's control, like stopping smoking, eating better, exercising more and it puts all the responsibility upon the individual and politically, that's very safe. ...But short of an individual quitting (his or her) job, which is not a fair choice, a person can't prevent a workplace cancer exposure on (his or her) own."
To learn more about the Canadian study, visit the Occupational Cancer Research Centre.
Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for the last decade.