Distribution of some natural and anthropogenic radionuclides in Sudanese harbour sediments

Abstract

The distribution of some natural and anthropogenic radionuclides (226p~a, 228Ra, 21~ 4~ 137Cs) in surface marine sediments from the harbours at Port Sudan and Sawakin on the Sudanese coast of the Red Sea has been investigated using a-spectrometry and direct high-resolution ~/-spectrometry. The prime aims were to assess the levels of radioactivity and the influence of factors such as dredging and the organic matter content of the sediments on the distribution pattern of the radionuclides. The results have been evaluated and the levels indicate the absence of any possible enhancement by anthropogenic influx from the hinterland. The spatial distribution pattern is more heterogeneous in Sawakin harbour where some parts have recently been dredged and the sludge is removed to maintain the required depth. The data also show an insignificant relationship between the activity concentrations of all the radionuclides and the content of organic matter in the sediments.

Radioactivity concentrations and their radiological significance in sediments of the Tema Harbour (Greater Accra, Ghana)

“…Nyarko et al (2011) also reported lower activity concentrations of 210 Pb in beach sand samples along the Ghana coast ranging from 1.6 up to 4.5 Bq kg À1 and 137 Cs concentrations below the detection limit of 0.4 Bq kg À1 . The mean radioactivity levels in the Tema Harbour sediments were also higher than the levels reported for the Mediterranean coast of Egypt (Higgy, 2000), but were comparable to (Sam et al, 1998), Patras Harbour, Greece (Papaefthymiou et al, 2007), Mumbai Harbour, India (Sugandhi et al, 2014), and the Karachi Harbour, Pakistan (Sugandhi et al, 2014). The mean radioactivity levels of 238 U, 232 Th, 40 K and 137 Cs in the Tema Harbour sediments were, however, much lower than those found in polluted sediments from the Caspian Sea coast of Iran (Abdi, Hassanzadeh, Kamali, & Raji, 2009).…”

“…In the coastal environment, harbours may be particularly susceptible to anthropogenic influences and their sediments can act as sinks for radionuclides (Sugandhi, Joshi, & Ravi, 2014). Harbours have hence been areas of interest when investigating radionuclide contamination in the coastal environment (Akram et al, 2006;Kumar et al, 2013;Papaefthymiou, Papatheodorou, Moustakli, Christodoulou, & Geraga, 2007;Sam, ElGanawi, Ahamed, & ElKhangi, 1998;Sugandhi et al, 2014). Sediment contamination by radionuclides of the 238 U and 232 Th decay-series and 40 K is of particular interest from radiological point of view, as they can form the basis of radiological assessments for the human population.…”

Radioactivity concentrations and dose assessment for soil samples around nuclear power plant IV in Taiwan

“…The 137 Cs was readily mixed with soil and by rain. However, the potential radiological impact on humans from such low levels of 137 Cs is insignificant (Adam et al 1998, Aarkrog et al 1997.…”