Childhood leukaemia's nuclear link

the largest ever cluster of childhood leukaemia cases in the vicinity of a nuclear facility has been reported by a German-American team of epidemiologists. The cluster of 15 children was found within 5 km of the Krmmel nuclear power plant in Geesthacht and a neighbouring nuclear research operation along the Elbe River in northern Germany.

This, the team says, is worrisome considering that there has been no reported accident or leak in the nuclear plant ever.

The team led by W Hoffmann of the Institute for Community Medicine at Ernst-Moritz-Arndt University of Greifswald, Germany, found that 14 children in the region, mostly below five, developed leukaemia between 1990 and 2005.

The scientists say this is the largest series of childhood leukaemia cases reported till date near any nuclear facility.The consistent numbers over the years also point towards the need for immediate large-scale epidemiological studies near nuclear facilities across the world, they reported in the June 2007 issue of Environmental Health Perspectives (Vol 115, No 6).

"Childhood leukaemia clusters have been observed at a number of sites near European nuclear facilities. With the identification of the largest cluster to date, this study underscores the need to clarify the association," Hoffman says.

Between February 1990 and May 1991, five cases of leukaemia were diagnosed in children living within 5 km of the facilities. By 2005, another nine cases of leukaemia had been discovered in the area. Most of the cases were acute lymphatic leukaemia in males under five years of age.

Earlier investigations had found moderate levels of cesium in rainwater and air samples, along with plutonium and americium in household dust near the plant. There was also some evidence of chromosomal damage to lymphocytes among the local population.

An expert committee looking into the cases suggested that population mixing -- the comingling of local people with newcomers from various places -- might have caused the cluster.

However, Hoffman's team does not agree. "Population mixing is unlikely to account for the leukaemia incidence because the population remained stable over the years studied. Nor would an alleged one-time release of radiation readily explain the cluster, given that the excess incidence persisted over at least 15 years."

They concluded that the high incidence of childhood leukaemia around Geesthacht remains "another piece in a growing puzzle" of childhood leukaemia's association with nuclear installations -- and its severity and persistence emphasise the need for investigation.

In the current study, researchers compared the number of observed leukaemia cases in the sparsely populated Geesthacht area to the number of predicted cases based on nearby county and national incidence rates between 1990 and 2005.

The five cases found in 1990 and 1991 significantly exceeded the expected incidence for that period of 0.45 cases. After studying medical records from all treatment facilities in the vicinity and in Hamburg, the team concluded that the Geesthacht cluster is the "largest series of childhood leukaemia cases reported to date" among European leukaemia clusters near nuclear facilities.