An ecological study of cancer incidence in Port Hope, Ontario from 1992 to 2007

A plant processing radium and uranium ores has been operating in the town of Port Hope since 1932. Given the nuclear industry located in the community and ongoing public health concerns, cancer incidence rates in Port Hope were studied for a recent 16 year period (1992-2007) for continued periodic cancer incidence surveillance of the community. The cancer incidence in the local community for all cancers combined was similar to the Ontario population, health regions with similar socio-economic characteristics in Ontario and in Canada, and the Canadian population. No statistically significant differences in childhood cancer, leukaemia or other radiosensitive cancer incidence were observed, with the exception of statistically significant elevated lung cancer incidence among women. However, the statistical significance was reduced or disappeared when the comparison was made to populations with similar socio-economic characteristics. These findings are consistent with previous ecological, case-control and cohort studies conducted in Port Hope, environmental assessments, and epidemiological studies conducted elsewhere on populations living around similar facilities or exposed to similar environmental contaminants. Although the current study covered an extended period of time, the power to detect risk at the sub-regional level of analysis was limited since the Port Hope population is small (16 500). The study nevertheless indicated that large differences in cancer incidence are not occurring in Port Hope compared to other similar communities and the general population.