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

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.