Atmospheric deposition fluxes of 137Cs associated with dust fallout in the northeastern Arabian Gulf

Abstract

For many years, monitoring and determining the radioactivity of ¹³⁷Cs in the environment has considerable interest. This paper presents monitoring ¹³⁷Cs deposition fluxes during the period from 2009 to 2011. Dust fallout samples were collected from ten locations in Kuwait, and ¹³⁷Cs concentrations were determined using ultra low spectrometry system. The average of the annual atmospheric deposition fluxes of ¹³⁷Cs was 4.3, with an extreme value reaching 50 Bq m^-2. The monthly deposition rates of ¹³⁷Cs were attributed to seasonal increases in the spring. ¹³⁷Cs deposition fluxes showed a significant relationship with dust deposition and precipitation rates, where the correlation between the monthly dust fallout and the ¹³⁷Cs deposition fluxes and precipitation rates were approximately 0.95 and 0.81, respectively. The spatial monthly distribution of ¹³⁷Cs fluxes showed high rates in the southeastern part of Kuwait while the lowest rates were recorded along the coastlines. A strong correlation was observed between the annual ¹³⁷Cs and ⁴⁰K deposition rates considering that both radionuclides deposition were governed by similar conditions. It was concluded that long-range transport from the northwestern areas along with the effects from local dust washout and the site specify played a major role in controlling the rate of ¹³⁷Cs deposition. The estimated annual effective dose equivalent due to external and internal exposures was insignificant and can be ignored. It is worthwhile to continue investigating the source origin of ¹³⁷Cs in Kuwait to enhance understanding of the radiological hazards in the country.

Keywords: (137)Cs; Atmospheric deposition; Dust fallout; Kuwait; Northeastern Arabian Gulf.