Risk assessment and natural radionuclide content in black-sand deposits of North Sinai coast, Egypt

The radioactivity levels and risk factors have been assessed for twenty-eight positions of Black-Sand (BS) surface deposits along the Mediterranean Sea coast of north Sinai, Egypt. Twenty-eight surface samples were collected from six local cities: El Ressa, Abo Sakl, Ghornata, El Arish, El Masaed, and El Rommana. The activity concentration values of the nuclides of the ²²⁶Ra, ²³²Th, and ⁴⁰K of the collected samples were measured using a P-type HPGe detector with a relative efficiency of ∼100% where it is defined at 1.33 MeV relative to a standard 3-inch diameter and 3-inch long NaI (TI) scintillator. El Ressa samples have relatively the most significant average values for ²²⁶Ra and ²³²Th, whereas El Rommana samples had the highest for ⁴⁰K. The radiation hazard calculations for the collected BS samples indicated significantly lower values than the internationally recommended limits. The ambient dose rates of the six areas under study were monitored and found to range from 0.06 to 0.10 μSv.h⁻¹.