Presence of radon in groundwater in parts of Bangalore

Abstract

Presence of high levels of Radon ( 222 Rn) gas was reported from groundwater in Bangalore. To ascertain the ground reality and the nature of the hazards, if any, a study was conducted by the Central Ground Water Board, Bangalore in and around Bangalore city. Groundwater samples from borewells and a dug well were collected and analysed. Available data on Radon gas from both groundwater and surface water sources were also compared. The presence of Radon gas and its concentration in groundwater were examined with respect to geology and well depths. The results are discussed in the paper.

Indoor 222Rn and 220Rn concentrations and doses in Bangalore, India

“…However, the higher concentration may be due to the higher activity concentrations of 226 Ra and higher concentrations of radon in water in all monitored locations. Shiva Prasad et al (9) and Hunse et al (10) have reported the activity concentrations of 226 ) concentrations for the environment of Bangalore were found to be comparable with the observation made elsewhere in India (8) . In general, radon concentrations were found to be higher in mud houses compared with cemented houses (21) .…”

“…Some buildings with higher radon levels were found on gravel, but all the lower values were observed in Rajajinagar area. This may be due to the lower activity concentrations (9) of 226 Ra and lower radon concentration in ground water in surrounding area (10) . However, the higher concentration may be due to the higher activity concentrations of 226 Ra and higher concentrations of radon in water in all monitored locations.…”

“…The average activity concentrations of 226 21 , respectively (9) . The occurrence of radon in the groundwater samples of the study area (10) is ranging from 55.9 to 1189.3 Bq l…”

“…This observed anomaly may be due to the fact that the class rooms were closed for a longer duration in summer holidays (April to June). Further, the higher concentrations in Gandhinagar may be due to the higher activity concentrations (9) of 226 Ra,232 Th and higher concentrations of radon gas in ground water in the surrounding area (10) . The winter to summer ratio in different locations were found to vary between 1.9 and 3.7, and this ratio is high compared with the ratio of winter to rainy and winter to autumn season.…”

“…, with concentration exceeding the permissible limit of 11.8 Bq l 21 and at some places it is as high as hundred times (10) . All the monitored houses were on ground floor.…”