ABSTRACT
Objective To understand the activity concentrations of natural radionuclides 40K, 226Ra, 232Th, and 238U in raw coal of coal mines in some regions of China, and to explore the correlation between ore with different activity concentrations and the concentration of radon and its progeny in the workplace. Methods Raw coal samples were collected in twelve coal mines in five provinces, and the activity concentrations of 40K, 226Ra, 232Th, and 238U were measured by a high-purity germanium γ-ray spectrometric system. Results The activity concentrations of four natural radionuclides in the raw coal samples of twelve coal mines were all lower than 1000 Bq/kg, and the activity concentration of 238U in one coal mine was close to 100 Bq/kg. The content of 40K, 226Ra, 232Th, and 238U in different coal mines varied greatly, but 226Ra, 232Th, and 238U were basically at the same level in the same coal mine. Conclusion None of the 12 coal mines belong to radio active mines. One of the coal mines investigated has the activity concentrations of 226Ra, 232Th, and 238U close to the standard limit for restricted-use management mines. It is suggested to study the correlation between the content of 226Ra in raw ore, intermediate products, tailings(slag), or other residues and the concentration of radon and its progeny in mines. Monitoring and protection of radon and its progeny in the decay chain should be strengthened for coal mines with high activity concentrations of natural radionuclides 226Ra, 232Th, and 238U.
ABSTRACT
Objective To explore the effect of radon and its progeny on the expression and mutations of p53 in lung tissue of mouse model. Methods Apoptosis was detected by terminal deoxynucleotidy transferase-mediated dUTP-biotin nick end labeling. The expression of p53 gene was analyzed by immunohistochemistry, Western blot and realtime-PCR. PCR-SSCP was used to detect the mutation of p53 in lung tissues. Results Compared with those in the control group, the apoptotic index were increased significantly in 30 WLM and 60 WLM groups( t = 18.11, -10.30,P ＜ 0.05 ). The p53 protein was increased significantly ( t = -11.08, P ＜ 0.05; t = - 7.00, P ＜ 0.0 ) ) in 30 WLM and 60 WLM groups. The mutation of p53 gene was not detected in lungs of radon-exposure mice. Conclusions Lung and bronchus might be the targets of radon and its progeny, and p53 gene plays an important role in the progression of radon-induced lung injury.
ABSTRACT
Objective To study the expression of JNK/SAPK(c-Jun NH2-terminal kinase/stress activated protein kinase)in lung and bronchus of radon-exposed mice.Methods Male BALB/c mice were exposed to radon and its progeny with the cumulative dose of 0.02,30 or 60 working level month(WLM),respectively.The expression levels of JNK/SAPK in lung and bronchus were determined with Real-Time PCR,Western blot and immunohistochemistry methods.Results The JNK mRNA levels in lung tissues of mice exposed to radon of 30 and 60 WLM were higher than those of the control by 3.56 and 2.96 times,respectively.The relative expression levels of JNK and phospho-JNK proteins were higher than those of the control by using Western blot and immunohistochemistry methods.Condusiom Expose to the radon and its progeny might activate the JNK/SAPK intracellular signaling pathway.