Mohamed Salama Mohamed Hegazy, Mohamed Tawfik Mohamed Safwat
Environmental Radiochemistry, Egyptian Atomic Energy, Cairo, Egypt.
Radiochemistry, Egyptian Atomic Energy Authorit, Cairo, Egypt.
Int J Radiat Biol. 2024;100(1):122-130. doi: 10.1080/09553002.2023.2242936. Epub 2023 Sep 7.
This work will focused on the environmental and radio-ecological impacts occurred on an Egyptian coastal region, based on the radiochemical measurement of U, Cs, Th, K. The novelty of the study was cleared by the using of new technique showing the integration of two biological RESRAD models, lead to a probabilistic estimation of the radionuclides bioaccumulation in different consumed marine organisms and determination the probability of human cancer risk at different ages.
The 20 water samples were collected and mounted into clean containers, and their decay products, were measured in Bq.L, using different quality assurance tools. The study will used different statistical analysis and different RESRAD modeling codes were used in the study to predict the degree of environmental and radio-ecological impacts at the studied area, this will be helpful in order to define the impacts resulted from the transferring and accumulation of different radionuclides.
showed that the highest human dose conversion factor values of (5, 10, 15, with adult ages) were measured in Th-232 (mrem/pCi) while the lowest ingestion conversion factors values were observed in artificial Cs. On the other hand the highest values of external risk factor in case of (5, 10, 15 with adult age) were observed in artificial Cs-137(mrem/pCi), while the lowest value of external risk factor with the same ages were observed in U-238. This will lead to continual monitoring of artificial Cs-137 in different marine coastal regions. The arrangement of the bioaccumulation value (BIV) in Bq.kg which being calculated by using RESRAD-Biota in case of crustacean animals will be as follow: U-238 > Th-232 > Cs-137, while the arrangement of BIV in case of fish animals will be: Cs-137 > U-232 > Th-232. On the other hand the arrangement of Internal Dose Conversion factors in case of crustacean animals will be: U-238 > Th-232 > Cs-137. While the arrangement of Internal Dose Conversion factors in case of fish animals will be: Cs-137> Th-232 > U-238.
RESRAD code's results showed that the arrangement of the bioaccumulation and Dose Conversion factors were depend on the type of marine living organism. RESRAD code also showed that there are increments of the calculated external risk factor values which resulted from the adult than all the infants (5,10 and 15 ages) ages this may be related to the continuous replacement of new human's body cells during the growth stages. The study results showed that, environmental bioaccumulation impacts of the artificial Cs-137 were very effective in both marine living organisms and human as this will support the relation between the ingestion Cs-137 in the body(inside the soft tissues), and the probability of the human cancer risk. On the other hand, study results showed the importance of using RESRAD BIOA code for the EIA's ecological and radiological studies which should be done for any future industrial coastal .projects.
本研究基于对铀(U)、铯(Cs)、钍(Th)、钾(K)的放射化学测量,聚焦于埃及沿海地区所发生的环境和放射生态影响。本研究的新颖之处在于采用了一种新技术,该技术整合了两个生物RESRAD模型,从而对不同食用海洋生物中放射性核素的生物累积进行概率估计,并确定不同年龄段人类患癌风险的概率。
采集了20份水样并装入清洁容器中,使用不同的质量保证工具,以贝可/升(Bq.L)为单位测量其衰变产物。本研究采用了不同的统计分析方法,并使用不同的RESRAD建模代码来预测研究区域的环境和放射生态影响程度,这将有助于确定不同放射性核素的转移和累积所产生的影响。
结果显示,钍 - 232(Th - 232)的成人(5、10、15岁)人体剂量转换因子值最高(毫雷姆/皮居里,mrem/pCi),而人工铯的摄入转换因子值最低。另一方面,人工铯 - 137(Cs - 137)的成人(5、10、15岁)外部风险因子值最高(毫雷姆/皮居里,mrem/pCi),而相同年龄段铀 - 238(U - 238)的外部风险因子值最低。这将导致对不同海洋沿海地区的人工铯 - 137进行持续监测。使用RESRAD - Biota计算的甲壳类动物的生物累积值(BIV,单位为贝可/千克,Bq.kg)排列如下:铀 - 238 > 钍 - 232 > 铯 - 137,而鱼类动物的BIV排列为:铯 - 137 > 铀 - 232 > 钍 - 232。另一方面,甲壳类动物的内照射剂量转换因子排列为:铀 - 238 > 钍 - 232 > 铯 - 137。而鱼类动物内照射剂量转换因子的排列为:铯 - 137 > 钍 - 232 > 铀 - 238。
RESRAD代码的结果表明,生物累积和剂量转换因子的排列取决于海洋生物的类型。RESRAD代码还表明,成人计算出的外部风险因子值比所有婴儿(5、10和15岁)年龄段都有所增加,这可能与生长阶段人体新细胞的持续更新有关。研究结果表明,人工铯 - 137对海洋生物和人类的环境生物累积影响都非常显著,这将支持人体软组织中摄入铯 - 137与人类患癌风险概率之间的关系。另一方面,研究结果表明了在任何未来的沿海工业项目的环境影响评估(EIA)的生态和放射学研究中使用RESRAD BIOA代码的重要性。