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

Purpose: To clarify the relationship between domestic radon exposure and th e occurrence of chromosomal aberrations, stable translocations especially, in peripheral blood lymphocytes. Materials and methods: The study comprised a total of 84 non-smoking indivi duals, divided into three groups according to radon concentration measureme nts performed in their homes: low radon concentration (< 100 Bq/m(3), mean 67 Bq/m(3)), medium (200-400 Bq/m(3), mean 293 Bq/m(3)) or high (> 800 Bq/m (3), mean 1737 Bq/m(3)). Minimum residence in the present low-rise house wa s 10 years. The soups were matched with regard to age, gender and medical e xposure. Fluorescence in-situ hybridization (FISH) was performed using chro mosome paints for chromosomes 1, 2 and 4; 1500 metaphases were scored from each individual. Results: Equal frequencies of translocations and also other aberrations, e. g. dicentrics and complex rearrangements, were obtained in each group. Sign ificant correlation of translocations with ape 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. Conclusions: Chronic exposure to high concentrations of domestic radon did not increase the rate of stable or unstable chromosomal aberrations in peri pheral blood lymphocytes detected by FISH chromosome painting. A strong age effect was observed.