Chromosome aberrations in peripheral lymphocytes of individuals living in dwellings with an increased level of indoor radon concentrations

Rao

et al. 2016

IJRR

Background: The varia on of the radon progeny concentra on in outdoor environment and meteorological parameters at fine resolu on were studied for one year at a con nental loca on, Na onal Atmospheric Research Laboratory, Gadanki, India. Materials and Methods: The concentra ons were measured using Alpha Progeny Meter by collec ng air samples at a height of 1 m above the Earth's surface at a known flow rate. Results: Radon progeny concentra on shows temporal varia ons on diurnal and monthly scales, and is due to mixing in the atmosphere. Peak in the early morning hours and low values during a*ernoon compared to nigh+me are due to differen al heat contrast between earth's surface and its atmosphere. However, the ac vity during February shows maximum compared to June/July months. The diurnal varia on of radon progeny shows posi ve correla on with the rela ve humidity and nega ve correla on with ambient temperature. The monthly mean ac vity of radon progeny for the year 2012 was found to be 4.76 ± 0.73 mWL. Conclusion: The mean concentra on of radon progeny in the study region is rela vely high compared to the other loca ons in India and may be due to the rocky terrains and trapping of air-masses near the observa on site due to its topography.

Section: Introductionmentioning

confidence: 99%

Variation of radon progeny concentration over a continental location

Kumar

Rao

et al. 2016

IJRR

“…The alpha particles emitted by the decay of deposited Rn daughters bombard the sensitive lung tissues, and continuous exposure may lead to malignant transformation, which results in lung cancer [1][2][3]. Chromosome aberrations in peripheral lymphocytes were also reported for individuals living in the dwellings of high radon concentrations of 80-13,000 Bq/m 3 [4]. It has been established that the dose due to the inhaled radon progeny accounts for more than 50% of the total radiation dose that the general public receive from natural sources [5].…”

Section: Introductionmentioning

confidence: 99%

Radon daughters’ concentration in air and exposure of joggers at the university campus of Bangalore, India

Ashok

Nagaiah

Isotopes in Environmental and Health Studies

2008

The concentration of radon daughters in outdoor air was measured continuously from January 2006 to December 2006 near the Department of Physics, Bangalore University campus, Bangalore. The concentration was measured by collecting air samples at a height of 1 m above the ground level on a glass micro fibre filter paper with a known air flow rate. The results show that the radon progeny concentration exhibits distinct seasonal and diurnal variations that are predominantly caused by changes in the temperature gradient at the soil-atmosphere interface. The concentration was found to be high from 20.00 to 8.00 hrs, when the turbulence mixing was minimum and low during the rest of the time. In terms of the monthly concentration, January was found to be the highest with September/August being the lowest. The diurnal variations in the concentrations of radon progeny were found to exhibit positive correlation with the relative humidity and anti-correlation with the atmospheric temperature. From the measured concentration, an attempt was made to establish the annual effective dose to the general public of the region and was found to be 0.085 mSv/a. In addition, an attempt was also made for the first time to study the variation of inhalation dose with respect to the physical activity levels. Results show that in the light of both the effect of chemical pollutants and radiation dose due to inhalation of radon daughters, evening jogging is advisable.

Indoor radon concentration and its possible dependence on ventilation rate and flooring type

Ashok

Nagaiah

Radiation Protection Dosimetry

2011

The results of radon concentration measurements carried out in dwellings with natural ventilation for 1 y in Bangalore are reported. Measurements, covering three sessions of the day (morning, afternoon, night) were performed two times in a month for 1 y at a fixed place of each dwelling at a height of 1 m above the ground surface in selected dwellings. The low-level radon detection system (LLRDS), an active method, was used for the estimation of radon concentration. The measurements were aimed to understand the diurnal variation and the effect of ventilation rate and flooring type on indoor radon concentration. The geometric mean (± geometric standard deviation) of indoor radon concentration from about 500 measurements carried out in 20 dwellings is found to be 25.4 ± 1.54 Bq m⁻³. The morning, afternoon and night averages were found to be 42.6 ± 2.05, 15.3 ± 2.18 and 28.5 ± 2.2 Bq m⁻³, respectively. The approximate natural ventilation rates of the dwellings were calculated using the PHPAIDA--the on-line natural ventilation, mixed mode and air infiltration rate calculation algorithm and their effects on indoor radon concentrations were studied. The inhalation dose and the lung cancer risk due to indoor radon exposure were found to be 0.66 mSv y⁻¹ and 11.9 per 10⁶ persons, respectively. The gamma exposure rate was also measured in all the dwellings and its correlation with the inhalation dose rate was studied.