Potential Impact of Occupational and Environmental Cancer Risks in Nigeria

Throughout their life people are exposed to a wide range of environmental and occupational pollutants from different sources in the work place, at home and in the general environment. Several chemicals, metals, dusts, fibres, and occupations have been established to be causally linked to an increased risk of cancer. Air pollution, from outdoor (mainly industrial and traffic related) and indoor (heating and cooking) sources, has been identified as a significant contributor to the environmental cancer burden. The annual global burden of occupational cancer deaths is estimated to be between 300,000 to 600,000. This estimate has large uncertainty as, firstly, for many established carcinogens the dose response relationship is not well described, secondly, exposure prevalence is unknown in many settings, and, thirdly, there are plausible hypotheses for further environmental carcinogens for which causation has not been established. With an estimated 102,000 new cancer cases in 2012, Nigeria has a substantially lower cancer burden which is about three times lower compared to high income countries. However, this is most likely underestimating the true cancer burden, as not all patients are seen in medical treatment centres. Lung cancer incidence is particularly low in Nigeria. Many carcinogenic risks in the workplace, at home or in the general environment are modifiable and the cancers therefore preventable. Given the long induction period of many cancers, successful primary prevention shows its benefit mainly in the long run. Nevertheless, primary prevention has to be implemented as early as possible, to reverse increasing trends in cancer occurrence. Cancer control plans including environmental and workers protection are therefore urgently needed for Nigeria.