Characterization of atmospheric dust at Gurushikar, Mt. Abu, Rajasthan

Abstract

The nature of atmospheric aerosols at Gurushikar, Mt. Abu, Rajasthan where a gamma ray telescope is to be installed, was investigated. Air particulate samples collected on filters were used to estimate the total suspended particulate matter (TSPM) and its elemental composition. The TSPM varied from 31 to 103 μg/m(3) during January to March 1994. The heighest loads were observed during the months of May and June (80-100 μg/m(3)) and lowest during October (20-60 μg/m(3)). The dust was also examined for size, shape and nature of the mineral matter. The particle sizes varied from 100 μm to 5 μm. The course particles (>50 μm) are irregular shaped quartz grains. Some of the medium size (=50 μm) particles were spherical and were highly conducting. These particles were rich in iron content. Correlation coefficients among various elements in the dust showed that it is made up of mainly two components-wind blown ground dust and particulate arising out of wood and coal burning.

Bulk Level to Individual Particle Level Chemical Composition of Atmospheric Dust Aerosols (PM5) over a Semi-Arid Urban Zone of Western India (Rajasthan)

“…Using measured elemental composition of individual particles, we assessed probable mineral phase abundant in aerosols over different sites following Kandler et al (2007Kandler et al ( , 2009 (Table 4). The probable mineral phases of the background mineral dust sampled in this study, thus, are consistent with previous studies of Peterson, (1968) and Negi et al (1996) as both the studies indicated presence of quartz (Si rich), hematite (Fe rich) and carbonates Ca rich minerals.…”

“…5 shows a few Fe-rich particles from Kukas area. In a previous study Negi et al (1996) studied TSPM and its elemental composition from Mount Abu, Rajasthan (high altitude region in the vicinity of Thar Desert) and reported particles with higher Fe contents. Chemical composition data of individual particles from the Makarana mining area show significant Ca contents (Fig.…”

“…Purpose of covering these locales was to capture regional heterogeneity in the measured data. PM 5 size ambient particles were chosen for sampling because studies by Negi et al (1996Negi et al ( , 2002 that have shown size of mineral dust particles in general vary (from aerodynamic diameter ~5 to ~50 µm) and particles with size 1-5 µm (PM 5 ) were found to be embedded on the surface of the large particles. Also due to their high residence time, interact more with the incoming radiation compared to large particles (Mishra and Tripathi, 2008).…”

Dust-Storm Source Areas Determined by the Total Ozone Monitoring Spectrometer and Surface Observations

“…Dust storms have received considerable attention in India (see, e.g., Joseph 1982;Negi et al 1996) and Middleton (1986b) has prepared a regional dust climatology. Dust from desert sources in southwest Asia provides a significant contribution to aerosols over the Arabian Sea (Chester, Berry, and Murphy 1991;Tindale and Pease 1999) and to its deep-sea sediments (Sirocko 1991;Bloemendal et al 1993).…”

Low dose inflammatory potential of silica particles in human-derived THP-1 macrophage cell culture studies – Mechanism and effects of particle size and iron

“…Transition metals such as iron are a common component of ambient particulate matter from various sources (street [11–15], street dust [16], automobiles [17–21], brush fire [22,23], coal combustion [24,25] and subway [26–28]). and contribute to the biologic effects of particles with different chemical properties [27, 29–33].…”