Study of health hazards associated with natural radioactivity in coal of Mach coal mines, Balochistan, Pakistan

The measurement of natural radioactivity in coal samples plays a vital role in investigating the radiological health hazards related to coal combustion, mining and disposal. This study was conducted to measure the natural radioactivity and associated health hazards in coal samples collected from Mach coal mines, district Kachhi, Balochistan by using High Purity Germanium (HPGe) detector. The concentration ranged from 41.25 ± 1.13 to 102.56 ± 3.35 Bq kg −1 for 226 Ra, 39.71 ± 1.23 to 127.85 ± 3.21 Bq kg −1 for 232 Th and 40.88 ± 1.2 to 168.34 ± 3.98 Bq kg −1 for 40 K with average values 74.44 ± 2.31, 85.07 ± 2.06 and 113.30 ± 2.99 Bq kg −1 , respectively. The values of 226 Ra and 232 Th were found higher than permissible limits, while in the case of 40 K all values were found less than permissible limit. The values of radium equivalent activity (Ra eq ), internal (H in ) and external (H ex ) hazards indices were found less than permissible limits. Pearson correlation test shows strong positive correlations between the radionuclides measured in this study. Similarly, frequency distribution, Q-Q and box plots show normal distribution of the radionuclides in the coal samples. Based on the radiological hazards indices, coal mines of Mach do not pose significant health hazards.