Abstract
The specific activity and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides (
238
U,
232
Th
, and
40
K
) were determined in roadside soil cores obtained from eight sites along Amman Aqaba National Highway (AANH), using HPGe gamma-ray spectrometry. The soil activity ranged from 22 to
104
Bq
kg
−1
for
238
U
, 21 to
103
Bq
kg
−1
for
232
Th
, and 138 to
601
Bq
kg
−1
for
40
K
. The highest mean value of
238
U
was found in the core samples obtained from a site close to Al-Hassa phosphate mine. The study yielded an annual effective dose equivalent in the range of 40–
151
μSv
. The average value falls within the global range of outdoor radiation exposure given in UNSCEAR-2000 publications.