Radiation hazard indices and excess lifetime cancer risk in sand from the northern and eastern regions of Kuwait

The radionuclide activity data of sand samples collected from the northern and the eastern regions of the state of Kuwait were implemented to evaluate the radiological safety of these two geographical areas. The northern area covered an approximate stretch of distance of 100 km spanning from northern Kuwait City to the border between Kuwait and Iraq. During the Gulf War, back in 1991, fierce sabotage and combat activities were carried out at this stretch of highway, consequently this highway was known as "Death's Highway'' or "Hell's Highway.'' The eastern region consisted of Failaka island (39 m(2)), a Kuwaiti territory, located 27 km to the east off the coast of Kuwait City in the northern part of the Arabian Gulf. The activity concentrations of natural radionuclides were determined using gamma (gamma)-ray spectrometry. The sand samples believed to be undisturbed, were collected from a number of locations at a depth of 5-20 cm from the surface. In the northern region, the mean activity concentrations for the radionuclides utilized to conduct the calculations were as follows; Th-232 at 30 Bq/kg, Ra-226 at 12 Bq/kg, and K-40 at 397 Bq/kg. While in the eastern region, the means were; Th-232 at 10 Bq/kg, Ra-226 at 15 Bq/kg, and K-40 at 333 Bq/kg. To evaluate the radiological hazards of the natural radioactivity at the studied regions, the radium equivalent activity, the annual gonadal dose equivalent, the representative level index, the external hazard index, the internal hazard index, the absorbed dose, and the effective dose rate were calculated and compared with international approved values. In addition, the measured activity concentrations were used to calculate the excess lifetime cancer risk. The calculated indices indicated that the radiation hazards from the primordial radionuclides at both regions are not significant; furthermore, the potential carcinogenic risk from the gamma radiation doses absorbed by the population is low.