Investigation of the 2018 Shiraz dust event: Potential sources of metals, rare earth elements, and radionuclides; health assessment

Atmospheric transport of microplastics during a dust storm

“…The air mass trajectory frequencies for the period directly preceding the dust storm and calculated using HYSPLIT are shown in Figure 4a. These frequencies indicate dominant westerly and southwesterly components associated with the event, with satellite imagery (Figure 4b) and geochemical signatures reported in Abbasi et al (2021b) confirming that the most important source of dust is the Arabian Peninsula, and in particular the Saudi Arabian deserts. Here, resuspension of material is favoured by extensive accumulations of fine sand and silt, scattered vegetation and variable terrain (Engelbrecht et al, 2017).…”

“…(2015) suggested that nearly 100 Mt of dust was emitted, with 73 Mt deposited over the broader region of study and including about 7 Mt deposited in the ocean. Assuming that the concentration of MP in the soils acting as a source of dust is about 0.02 MP g -1 (Abbasi et al, 2021b), we estimate that such a storm could suspend about 2 x 10 12 MP and deposit 1.5 x 10 12 MP regionally, including 1.5 x 10 11 MP in the ocean. Globally, it is estimated that about 2 billion tonnes of loose and poorly vegetated arid soil are transported in the atmosphere each year (Perkins, 2001;Tanaka and Chiba, 2006), with the main source regions associated with the Sahara desert and the deserts of Asia, the Middle East, North and South America and Australia (Wang, 2015).…”

“…The air quality of Shiraz has declined over recent years because of the rapid growth in population, traffic volume and industrialization (Gharehchahi et al, 2013), coupled with an increased incidence of dust storms (Alizadeh-Choobari et al, 2015). The frequency of dust "events" in Shiraz appears to be between 1 and 3% (Alizadeh-Choobari et al, 2015) but on May 13 th 2018, a particularly intense dust storm occurred in the region that involved the transboundary transportation of geogenic material originating in Saudi Arabia across the Persian Gulf (Abbasi et al, 2021b).…”

“…Thus, the estimated range in contributions of MP that are local to Shiraz to the sampled dust particles is about 0.1 to 5%, with variations amongst the locations presumably reflecting differences in the proximity to or mobility of urban sources but displaying no clear relationship with particle characteristics (e.g., size, colour or shape). The majority of MP are, however, clearly imported from outside the region (and via Saudi Arabia and southwest Iran), with geochemical analyses of dust samples suggesting that the Arabian Peninsula provides the more significant, transboundary contribution (Abbasi et al, 2021b).…”

Determination of the threshold velocity of soil wind erosion using a wind tunnel and its prediction for calcareous soils of Iran

“…The maximum wind velocity varied from 30 m s −1 in Abadeh and Shiraz to 45 m s −1 in Eghlid. In addition, several dust storm events have been reported in this province, such as on July 17, 1998, August 13, 2001, April 24, 2008, February 28, 2009, August 28, 2013, and May 13, 2018 (Abbasi et al, 2021; Mazidi et al, 2015).…”