The effect of air mass origin on the ambient concentrations of 7Be and ²¹°Pb in Islamabad, Pakistan.

Concentration of radionuclides ²¹°Pb and 7Be, having half lives of 22.3 years and 53.29 days, respectively, in the surface air samples of Islamabad (33.38°N, 73.10°E and Altitude ∼536 m asl.) are measured. The non-destructive technique of gamma-spectrometry, with a high purity germanium HPGe detector, was employed for the analysis of all samples. The annual average concentrations of ²¹°Pb and 7Be in the surface air samples were determined as 0.284 ± 0.15 and 3.171 ± 1.14 mBq m⁻³, respectively. Our results have shown a seasonal variation of the concentration of 7Be in air samples with high values for the spring season. High concentrations for ²¹°Pb are obtained when air masses originate from plain areas of Pothohar region, located in the South-West, West and North West of Islamabad. Our values of concentrations show a nice agreement with the relevant reported results.

Radon monitoring in water sources of Balakot and Mansehra cities lying on a geological fault line.

This paper relates to a series of systematic studies regarding measurement of radon concentration in the earthquake-affected areas of northern Pakistan. Radon is a radioactive alpha-particle-emitting gas originating from the decay series of uranium and thorium and is found anywhere in soil, air and water. The nature of water does not matter with regard to the presence of radon, however, the level of radon concentration varies in different types of water. The present survey is carried out in water samples from the fault zone of Balakot and Mansehra regions, North West Frontier Province, Pakistan, which is important for geological consideration and protection from radiation hazards. The measurements were made on a Pylon system that is based on the radon gas measurement with a Lucas cell. In 72 water samples in the equilibrium state between radon and its progeny, the concentration level of radon is measured. The results show that the radon concentrations are in the range of 4.99-24.52 kBq/m(3), with an average value of 15.52 kBq/m(3) for all types of water taken in this survey.

Fission track estimation of uranium concentrations in drinking water from Azad Kashmir, Pakistan.

The analysis of uranium in water samples can be very helpful for providing guidelines to the general public regarding necessary remedial measures. A fission-track technique has been applied for the estimation of the uranium concentration in drinking water collected from natural springs of Muzaffarabad and hilly areas of Reshian, Azad Kashmir. The technique involved simultaneous irradiation with thermal neutrons of a sample and a standard in contact with a track detector, and the counting of the fission tracks in the detector from the (n, f) nuclear reaction. Uranium concentrations of the samples were determined by comparing fission-track density with that of a standard of known uranium concentration. Uranium concentration in water samples from the Muzaffarabad and Reshian area varied from 0.03 +/- 0.01 microgL(-1) to 6.67 +/- 0.14 microgL(-1) with an average of 1.36 +/- 0.05 microgL(-1). The observed concentrations of uranium in drinking water were found to be less than the Maximum Acceptable Concentration levels of 9-30 microgL(-1). Thus, the observed values are within safe limits as far as uranium related health hazards are concerned.