Domestic radon exposure and the frequency of stable or unstable chromosomal aberrations in lymphocytes

To clarify the relationship between domestic radon exposure and the occurrence of chromosomal aberrations, stable translocations especially, in peripheral blood lymphocytes.

The study comprised a total of 84 nonsmoking individuals, divided into three groups according to radon concentration measurements performed in their homes: low radon concentration (<100Bq/m3, mean 67Bq/m3), medium (200-400Bq/m3, mean 293Bq/m3) or high (>800Bq/m3, mean 1737Bq/m3). Minimum residence in the present low-rise house was 10 years. The groups were matched with regard to age, gender and medical exposure. Fluorescence in-situ hybridization (FISH) was performed using chromosome paints for chromosomes 1, 2 and 4; 1500 metaphases were scored from each individual.

Equal frequencies of translocations and also other aberrations, e.g. dicentrics and complex rearrangements, were obtained in each group. Significant correlation of translocations with age was observed, and due to the high mean age (50 years) the genome-corrected frequency of translocations was high: about one translocation in 100 metaphases.

Chronic exposure to high concentrations of domestic radon did not increase the rate of stable or unstable chromosomal aberrations in peripheral blood lymphocytes detected by FISH chromosome painting. A strong age effect was observed.