Brick, sand, marble and cement are mainly used for the construction of
dwellings in Pakistan. Therefore, knowledge of the presence of natural
radioactivity in these materials is of great importance in order to assess the
radiological hazards associated with them. In this context, specific activities of
226Ra,
232Th
and 40K
were measured in brick, sand, marble and cement samples collected from different localities of the
North West Frontier province and federally administered tribal areas, Pakistan, using a P-type
coaxial high-purity germanium spectrometer. In brick samples, the average measured activities for
226Ra,
232Th
and 40K
were 30 ± 15, 41 ± 21
and 523 ± 182 Bq kg−1, whereas in sand samples, these values were
19 ± 9,
30 ± 15
and 769 ± 461 Bq kg−1, respectively. In marble samples, the average specific activities of
226Ra,
232Th and
40K were
found to be 18 ± 19, 18 ± 21
and 299 ± 328 Bq kg−1, whilst in cement
samples they were 24 ± 6, 18 ± 4
and 244 ± 29 Bq kg−1, respectively. Radium equivalent activities were also calculated and were found to be
129 ± 54,
121 ± 57,
67 ± 60
and 68 ± 9 Bq kg−1 for
brick, sand, marble and cement samples, respectively. The annual average effective doses from these samples
were 0.37 ± 0.15, 0.33 ± 0.15, 0.20 ± 0.17
and 0.20 ± 0.03 mSv, respectively. External and internal hazard indices were less than one for all the
samples studied.