@misc{oai:repo.qst.go.jp:00069484,
 author = {Zhang, Wei and Chun, Yan Wang and Minamihisamatsu, Masako and Luxin, Wei and Sugahara, Tsutomu and Hayata, Isamu and 張 偉 and 王 春燕 and 南久松 眞子 and 早田 勇},
 month = {Jul},
 note = {Smoking is the most influential factor among the environmental mutagens to increase cancer incidence. Previously we reported that the effect of smoking on the induction of chromosome aberration in the residents in high background radiation area (HBRA) was larger than that of the elevated level of natural radiation in China (Zhang et al., 2004). In order to know how environmental mutagens affect the induction of translocations caused by smoking we analyzed the translocations in the lymphocytes of smokers in a large city, Beijing, and compared them with those in a high background radiation area (HBRA) and in its control area (CA), remote villages, in South China. The studied residents in Beijing have lived there for longer than 40 years. The level of natural radiation in HBRA is 3 - 5 times higher than those in CA and in Beijing. The residents in remote villages (HBRA and CA) mainly smoke the shredded tobaccos through a water pipe instead of the cigarette which is common in Beijing. Individual radiation dose was measured with a pocket dose meter (Aloka PDM-10) put on the body for 24 hours. Peripheral blood was obtained from 5, 10, and 7 smokers in Beijing, HBRA and CA, respectively. Their ages were around 60 years old. Peripheral lymphocytes were cultured for 48 hours with PHA and colcemide, and harvested according to our standard method for biodosimetry. Chromosomes #1, #2, and #4 were painted for the analysis of translocations. The number of metaphases analyzed was totally 90,267 (4,103 per resident). Statistical analysis was done by Mann-Witteney's U test. 
Genomic frequencies of translocation in 1,000 lymphocytes per smoker are 8.7+/-3.0, 11.1+/-3.6 and 13.4+/-3.4 in Beijing, HBRA and CA, respectively. Standard deviation is similar among three groups. CA group shows the highest average value among three groups. There was a statistically significant difference (p>0.05) in the frequencies of translocation between the smokers in Beijing and those in CA, but no other possible comparisons between groups showed significant difference. The effect of smoking seems to be suppressed by the environmental mutagens including the elevated level of natural radiation in HBRA. Further study is in progress to see if such suppression effect is statistically significant or not., 13th International Congress of Radiation Research},
 title = {Effect of smoking reflected in the stable chromosome aberrations in the lymphocytes of the residents in the areas exposed to different environmental mutagens including radiation.},
 year = {2007}
}