This investigation was initiated by the Northern Territory Chief Health Officer under the provisions of the Public and Environmental Health Act to investigate a potentially serious public health issue, namely a finding that all cancer incidence and the fetal death rate were higher for Aboriginal residents of the Gunbalanya-Kakadu (G-K) area than for the rest of the Aboriginal population of the Top End of the Northern Territory. 

Key Findings:

• The G-K cluster investigation has confirmed that the fetal death rate and the incidence of all cancers combined, head and neck cancers and lung cancer was higher than expected when compared to the Top End Aboriginal population.
• The level of environmental radiation exposure under the worst-case scenario would have produced a very small increase in cancer incidence compared to a population exposed to average levels of environmental radiation.
• This investigation has only partially explained the higher incidence of fetal deaths and has not explained the higher incidence of cancers in the G-K population. However, high levels of smoking and alcohol consumption in this population point to actions that could be taken to improve the overall health of the GK population that would continue the decline in fetal death rates and decrease cancer incidence.
• There is national evidence that the prevalence of smoking is decreasing in the Aboriginal and Torres Strait Islander population, which is encouraging and to be encouraged for the G-K communities. The 21% higher prevalence of alcohol consumption in the G-K cohort is a cause for serious concern; if frequency and volume of consumption are also high, this would be causing major health and social problems for the G-K population.