期刊名称：Research Journal of Environmental and Earth Sciences
印刷版ISSN：2041-0484
电子版ISSN：2041-0492
出版年度：2011
卷号：3
期号：6
页码：729-736
出版社：Maxwell Science Publications
摘要：Beaches along the coastlines in Ghana are important holiday destinations for tourists from many countries around the world. The radiological quality of sand from these beaches is very important to assess exposure of the public who use the beaches for recreational purposes and other activities. This study investigates the levels and hazards associated with the U-Th series and 40 K in beach sands from some renowned tourist resorts in the Greater Accra region of Ghana. Samples of beach sand from eleven beaches were analyzed using direct gamma-ray spectrometry. The total absorbed dose rate and the annual effective doses were calculated. The radiation hazards and risks associated with the use of the beach sand as construction material were also determined. The results show specific activities in the range 11.0-31.8 Bq/kg for 238U, 0.5-1.5 Bq/kg for 235U, 10.9-103.7 Bq/kg for 226Ra, 16.8-231.2 Bq/kg for 232Th and 68.3-183.9 Bq/kg for 40K. Mean values of the absorbed dose rate, annual external effective dose, radium equivalent activity, external and internal hazard indices and the radiation level index are; 54.08 nGy/h, 0.066 mSv/y, 101.0 Bq/kg, 0.27, 0.36 and 0.71, respectively. The 235U/238U activity ratios calculated for the beaches is in the range of 0.032-0.053 with an average of 0.045±0.007 and that of the other radionuclides are close to unity, indicating only natural radionuclides were detected in the samples investigated. The results are within the values found in literature and show that the natural radionuclides in samples of the beach sand do not pose any significant risk to tourists and other holiday makers. Sand from the beaches is also safe for use as construction material, indicating the relevance in terms of the radiological quality of the beaches from both human and environmental health view points.
