In the 11th report of the Committee on Medical Aspects of Radiation in the Environment (COMARE), children growing up in an affluent urban environment and children from rural areas are at higher risk for developing many cancers.

Researchers studied cancer clusters where leukemia and other childhood cancers were reported, and have come to the conclusion that affluent children are being raised in an environment that is too clean. Called the dirty hypothesis, children living in too sterile an environment where they are not exposed to infection have weak immune systems.

For rural children, infection brought in to the rural community by people from larger populated urban areas, might be causing genetic damage that leads to cancer.

With the exception of the processing plant at Sellafield in Cumbria, and Dounreay in Scotland, the researchers also state they found no general pattern of increased cancer incidence around nuclear plants.

The researchers feel confident in the reported results of this study. They invite further study into the hypothesis of their findings. The database was constructed from the National Registry of Childhood Tumours by staff of the Childhood Cancer Research Group in Oxford, and included 12,415 cases of childhood leukemia and non-Hodgkin lymphoma and 19,908 cases of children with solid tumors registered under the age of 15 in England, Wales and Scotland from 1969 to 1993. To download the 160 page report, go here.