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Objective:To explore the disturbance of metal element balance in mice after exposure to radon.Methods:Mice were randomly divided into control group, radon exposure of 30 WLM group, 60 WLM group and 120 WLM groups, with 10 mice in each group. After radon exposure with the cumulative dose, the lung function of mice was detected by a non-invasive pulmonary function testing instrument. Mice blood was taken from eyeballs. The lungs, heart, liver, kidney and spleen were also collected. HE staining was used to observe the pathological changes of lung tissue. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the content of metal elements, including essential trace elements in the body: chromium (Cr), molybdenum (Mo), cobalt (Co), selenium (Se), copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni), and potentially toxic elements: arsenic (As), tin (Sn), lead (Pb), aluminum (Al), mercury (Hg), cadmium (Cd), and silver (Ag).Results:Compared with the control group, lung ventilation function of the radon-exposed mice was decreased, alveolar structure was destroyed, and the contents of pulmonary metal elements Cr, Al, Pb, Sn( F=0.34, 0.66, 3.14, 1.16, P<0.05) and essential trace elements Mn, Cr, Zn, and Mo in the blood were decreased( F=0.65, 1.44, 0.97, 2.08, P<0.05), while the elements of Cu, Mo, Se and As in the lungs were increased( F=1.31, 1.26, 0.81, 2.04, P<0.05), and the element contents in other tissues also fluctuated. Conclusions:Inhalation of a certain cumulative dose of radon can reduce the lung ventilation function of mice and induce lung inflammation, as well reduce the content of essential trace elements in the lung and blood so that the content of metal elements in the body fluctuates.
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Objective To evaluate the influence of indoor air filtration by air purifier on the behavior of indoor radon progeny and estimate its effects on indoor radon exposure to residents.Methods The concentrations of indoor radon progeny with and without the air filtration were calculated by the theoretical model developed in this study.Based on the dose conversion factors of attached and unattached radon progeny,the mitigation effects of indoor radon exposure due to the air filtration were estimated.Verification experiments were conducted in an airtight room.Results With the air filtration rate increased,the removal efficiency of indoor radon progeny would appear more obvious.For an airtight room with its initial aerosol concentration of 10 000 cm-3,the concentration of total radon progeny would decrease by more than 90％ when the air filtration rate exceeded 10 h-1.But the concentrations of indoor unattached radon progeny would increase by using the air purifier in different extents.The variations of radon progeny concentrations and the decrease of internal doses were closely related to the filtration rate of air purifier.With the air filtration rates increased,the mitigation effects would be better and faster.The internal dose would reduce by more than 70％ when the filtration rate exceeded 5 h-1.Conclusions Although the indoor concentration of unattached radon progeny will increase by using the air purifier,it is still effective in reducing the exposure dose to residents due to the inhalation of radon progeny.
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Objective To study the distribution characteristics of radon progeny at different air quality index (AQI) and evaluate health risks for the exposed population.Methods EQF3120 Monitor was used to monitor the concentration of radon and its daughters.The relevant air quality data was provided by the environmental monitoring station at Suzhou Industrial Park.SPSS 16.0 software was used for statistical description,principal component analysis and simple correlation analysis.Environmental radon exposure-caused effective dose to lung region was estimated by using the radon dose formulas.Results Radon progeny in fog haze weather in winter of Suzhou Industrial Park had relationships with NO2,SO2,O3,PM10 and PM2.5.The correlation coefficient of 214Bi were 0.741,0.681,-0.431,0.597 and 0.675.The correlation coefficient of radon progeny with PM2.5 was greater than that with PM10.When AQI ＞ 200,the effective dose to residents outdoor from radon and its short-lived progeny was 0.63 mSv/a.Conclusions Higher AQI results in higher concentration of attached radon progeny.There is little variation in concentration of unattached radon progeny.Fog and haze can increase exposure of the population to inhalated radon.