DETERMINATION OF HAZARDOUS LEVELS OF HARVESTED CONSTRUCTION SAND IN SELECTED RIVERS OF BUNGOMA COUNTY, KENYA

The average activity concentration for the three primordial radioactive nuclides were; 2±0.1Bq/kg with a range of 0± 0.03Bq/kg to 4±0.24Bq/kg for 238U, 55±2.78Bq/kg with a minimum value of 32±1.6Bq/kg and a maximum value of 87±4.38Bq/kg for 232Th and 51±2,56Bq/kg with a minimum value of 27±1.37Bq/kg and a maximum value of 76±3.8Bq/kg for 40K. The mean activity concentrations for 238U and 40K were below the world averages of 33Bq/kg and 420Bq/kg respectively. Radium equivalent varied from 6±0.32Bq/kg to 986±Bq/kg with an average value of 230±11.51Bq/kg. This was below the world’s permissible value of 370Bq/kg. Internal and external hazard indices ranged between 0±0mSv/y to 2.6±0.13 mSv/y with a mean of 0.6±0.003mSv/y, 0±0 mSv/y to 2.6±0.13 mSv/y with a mean of 0.6±0.003mSv/y respectively. These radiological parameters show an insignificant radiological health risk associated with the harvesting and use of sand in construction from the selected rivers. This study is essential to the general and inhabitants of Bungoma County as they are able to know the risks associated by the use of sand from the selected reivers in Bungoma County.