Workplace exposure studies have greatly increased our understanding of cancer and its causes. Carcinogens such as asbestos, benzene, chromium, and radon were first identified in occupational environments. Many exposures identified through occupational studies are also found outside the workplace, and therefore affect the wider environment and non-workers. In light of the importance of occupational cancer studies, Blair and coworkers recently highlighted a number of areas in which future research is needed.
To date, most occupational cancer research has focused on white men in developed countries. However, many industries are moving from developed countries to the developing countries. Therefore, other populations need to be incorporated into epidemiology studies to fully understand the impact of workplace exposures. Studies in developing countries are slowly becoming more common, but more work still needs to be done in this area.
More quantitative exposure studies are also needed. Quantitative assessments are still fairly rare in occupational cancer studies, but they are needed in order to accurately determine the relationships between exposure and cancer. Many studies assess exposure by recording only whether a person has ever been exposed to the substance in question, and do not look at the level of exposure. The risks of exposure are often underestimated by this type of study. As well, quantitative exposure assessments are needed in order to make effective regulatory policies and set maximum allowable exposure levels.
Despite the importance of occupational cancer research and interventions, little has been done to assess the effect of intervention efforts aimed at controlling exposure to carcinogenic substances. It can be difficult to document the impact of interventions due to the time lapse between the intervention, the decreased exposure to the carcinogen, and the reduction in cancer incidence. Identifying successful interventions and areas that still need improvement is critical to reducing the burden of cancer.
Occupational cancer research has identified a wide number of carcinogens that can be found both within and outside the workplace. The growing number of suspected carcinogens highlights the importance of continued research in this field. The researchers recommend that future studies include developing countries and minority populations, instead of focusing on white males. Quantitative exposure studies should be performed whenever possible. Finally, interventions need to be assessed for their effectiveness, so that the information we gain from research is translated into healthier, safer working environments.
Blair, A., Marrett, L., Freeman, L.B. Occupational cancer in developed countries. Environmental Health, 2011; 10(Suppl 1): S9.