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In Rechna Doab, samples of the most common vegetation, perennial grass Desmostachya bipinnata (dab), were collected along with soil samples from 29 sites. Natural radioactivity of ²²⁶Ra, ²³²Th/²²⁸Ac and ⁴⁰K was measured by using high purity germanium-based gamma ray spectrometer. Activity concentration levels of ²²⁶Ra, ²³²Th/²²⁸Ac and ⁴⁰K in soil were found to be 46.8 ± 6.2 (36.0-57.6), 61.4 ± 5.9 (48.2-73.2) and 644.8 ± 73.9 (537.7-868.4) Bq kg⁻¹ (dry mass), respectively, and those in vegetation were 2.74 ± 1.70 (1.00-6.39), 2.24 ± 0.59 (1.56-2.61) and 172.72±113.37 (53.14-469.24) Bq kg⁻¹ (dry mass), respectively. The measured values of the activity concentration in vegetation are comparable with some other international data. Calculated soil to vegetation transfer factors of ²²⁶Ra, ²²⁸Ac and ⁴⁰K were 0.06 ± 0.03 (0.02-0.14), 0.04 ± 0.01 (0.03-0.04) and 0.26 ± 0.16 (0.09-0.69). The mean outdoor absorbed dose rate in air for the area under study was determined as 8.22 nGy h⁻¹ and the mean indoor absorbed dose rate in air was 11.52 nGy h⁻¹. The total annual effective dose to the general public from the vegetation was found to be (0.02-0.16) mSv, which is below the recommended limit value of 1 mSv y⁻¹ for the general public. The dab vegetation under study was found to be radiologically safe for the population and environment.

The activity concentration of natural and anthropogenic radionuclides and associated doses were determined in soil samples collected from Muree and its surroundings to provide baseline radioactivity data. High purity Germanium (HPGe) based spectrometry system was used for determination of activity concentration. The activity concentration of 226 Ra, 232 Th, 40 K and 137 Cs varied between 20.0─29.5, 43.4─62.4, 163.0─493.6 and 1.3─54.1Bqkg-1 respectively. Radium equivalent activity was measured in range 107-148 with average 128.0Bqkg-1 .The average annual effective absorbed dose was found to be 72.9 ±1.0µSvy-1 which was comparable to world's average. The radium equivalent activity Ra eq , indoor and outdoor hazard indices were lower than the safe limit of Organization for Economic Cooperation and Development (OECD) report for general public.

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