Geraldo L P, Serafim R A M, Corrêa B A M, Yamazaki I M, Primi M C
Universidade Católica de Santos, UNISANTOS, Rua Dr. Carvalho de Mendonça 144, CEP 11070-100 Santos (SP), Brazil.
Radiat Prot Dosimetry. 2010 Jun;140(1):96-100. doi: 10.1093/rpd/ncq037. Epub 2010 Feb 16.
In this work, the uranium (U) content in sediment and soil samples collected near the Santos and São Vicente estuaries was determined using the fission track registration technique (SSNTD). The sediment and soil samples after oven-dried and pulverised were prepared in the solution form. About 10 microl of this solution was deposited on a plastic detector and irradiated at the IPEN-IEA-R1 (3.5 MW) nuclear reactor. After the irradiation and chemical etching of the plastic foils, the fission tracks were counted with a system consisting of an optical microscope together with a video camera and a PC. The U content in the analysed samples ranged from 3.12 +/- 0.55 to 18.3 +/- 1.2 ppm for sediments and from 3.21 +/- 0.63 to 11.5 +/- 1.1 ppm for soils or in terms of (238)U equivalent activity from 38.5 +/- 6.8 to 226 +/- 15 and 39.6 +/- 7.8 to 142 +/- 14 Bq kg(-1) for sediments and soils, respectively. These results were compared with other values reported in the literature for sediments and soils collected in environments similar to the ones studied in this work. Most of the values obtained in this work are higher than the world mean and are in reasonable agreement with results found by other authors for sediments and soils from regions considered as polluted or with a high level of radioactivity.
在本研究中，使用裂变径迹登记技术（固体核径迹探测器）测定了在桑托斯和圣维森特河口附近采集的沉积物和土壤样品中的铀（U）含量。将烘干并研磨后的沉积物和土壤样品制成溶液形式。将约10微升该溶液滴在塑料探测器上，并在IPEN - IEA - R1（3.5兆瓦）核反应堆中进行辐照。在对塑料箔进行辐照和化学蚀刻后，使用由光学显微镜、摄像机和个人电脑组成的系统对裂变径迹进行计数。分析样品中的铀含量，沉积物为3.12±0.55至18.3±1.2 ppm，土壤为3.21±0.63至11.5±1.1 ppm；或者以（238）U等效活度计，沉积物分别为38.5±6.8至226±15 Bq kg-1，土壤为39.6±7.8至142±14 Bq kg-1。将这些结果与文献中报道的在与本研究类似环境中采集的沉积物和土壤的其他值进行了比较。本研究中获得的大多数值高于世界平均值，并且与其他作者在被认为受污染或放射性水平高的地区的沉积物和土壤中发现的结果合理一致。
