Thodoros Glytsos

The effect of dust emissions from open storage piles to particle ambient concentration and human exposure

The current study focus on the determination of dust emissions from piles in open storage yards of a municipal solid waste (MSW) composting site and the subsequent atmospheric dust dispersion. The ISC3-ST (Industrial Source Complex Version 3 - Short Term) model was used for the evaluation of the PM(10) ambient concentrations associated with the dispersion of MSW compost dust emissions in air. Dust emission rates were calculated using the United States Environmental Protection Agency proposed dust resuspension formulation from open storage piles using local meteorological data. The dispersion modelling results on the spatial distribution of PM(10) source depletion showed that the maximum concentrations were observed at a distance 25-75 m downwind of the piles in the prevailing wind direction. Sensitivity calculations were performed also to reveal the effect of the compost pile height, the friction velocity and the receptor height on the ambient PM(10) concentration. It was observed that PM(10) concentrations (downwind in the prevailing wind direction) increased with increasing the friction velocity, increasing the pile height (for distances greater than 125 m from the source) and decreasing the receptor height (for distances greater than 125 m from the source). Furthermore, the results of ISC3-ST were analysed with the ExDoM (Exposure Dose Model) human exposure model. The ExDoM is a model for calculating the human exposure and the deposition dose, clearance, and finally retention of aerosol particles in the human respiratory tract (RT). PM(10) concentration at the composting site was calculated as the sum of the concentration from compost pile dust resuspension and the background concentration. It was found that the exposure to PM(10) and deposited lung dose for an adult Caucasian male who is not working at the composting site is less by 20-74% and 29-84%, respectively, compared to those for a worker exposed to PM concentrations at the composting site.

Measurements of particulate matter concentrations at a landfill site (Crete, Greece).

Large amounts of solid waste are disposed in landfills and the potential of particulate matter (PM) emissions into the atmosphere is significant. Particulate matter emissions in landfills are the result of resuspension from the disposed waste and other activities such as mechanical recycling and composting, waste unloading and sorting, the process of coating residues and waste transport by trucks. Measurements of ambient levels of inhalable particulate matter (PM(10)) were performed in a landfill site located at Chania (Crete, Greece). Elevated PM(10) concentrations were measured in the landfill site during several landfill operations. It was observed that the meteorological conditions (mainly wind velocity and temperature) influence considerably the PM(10) concentrations. Comparison between the PM(10) concentrations at the landfill and at a PM(10) background site indicates the influence of the landfill activities on local concentrations at the landfill. No correlation was observed between the measurements at the landfill and the background sites. Finally, specific preventing measures are proposed to control the PM concentrations in landfills.

A methodology for the determination of fugitive dust emissions from landfill sites

This study focuses on the development of a methodology for the determination of the contribution of fugitive dust emissions from landfill sites to ambient PM10 concentrations and the subsequent exposure to working personnel. Fugitive dust emissions in landfills mainly originate from resuspension due to truck traffic on paved and unpaved roads and from wind-blown dust from landfill cover soil. The results revealed that exposure to PM10, originating from fugitive dust emissions in the landfill site, was exceeding the health protection standards (50 μg m−3). The higher average daily PM10 concentration (average value) for weekdays was equal to 275 μg m−3 and was computed for the areas nearby the unpaved road located inside the landfill facilities that lead to the landfill cell. The percentage contributions of road and wind-blown dust to the PM10 concentrations on weekdays were equal to 76 and 1 %, respectively. The influence of the background concentration is estimated close to 23 %.

Ambient Particulate Matter Concentration Levels and their Origin During Dust Event Episodes in the Eastern Mediterranean

The eastern Mediterranean region is strongly influenced by long-range transported particulate matter such as desert dust from northern Africa. To investigate the dynamics of Saharan dust events and their origin, satellite images from the MODIS spectroradiometer of NASA’s satellites Terra and Aqua, and back trajectories analysis of the HYSPLIT model were combined together with continuous ground-based field data. Field PM10 and PM2.5 measurements were performed in the period 2003–2013 at the Akrotiri monitoring station on the island of Crete (Greece). Furthermore, the mineralogical composition of a small number of samples was determined by X-ray powder diffraction, whereas elemental particle composition analysis was performed on the dust samples collected using the ICP-MS technique for a series of elements. The annual average percentage of days with Sahara dust outbreaks in the region of western Crete (Akrotiri station) was 9.3% for the period 2003–2013. Excluding the PM10 exceedances caused by Sahara dust events, the average PM10 monthly concentrations are decreased by 20.5% during the 8-month period November–June, with higher PM10 concentration reduction (29.9%) in the period February–April. Mineralogical analysis showed that illite was the most abundant mineral identified in all samples, followed by quartz and calcite. Gypsum was detected only in the dry sample. Moreover, the elemental particle composition analysis showed that collected dust originated from Africa deserts.

Fine and coarse particle mass concentrations and emission rates in the workplace of a detergent industry

Aerosol mass concentration (PM10, PM2.5) measurements were conducted in the workplace of a detergent industry for two time periods during July 2005 and January 2006, using two portable real-time photometric monitors. The results showed increased mass concentrations both for PM10 and PM2.5 particles during the detergent production periods. The differences in the concentrations of the PM10 and PM2.5 particles were used to determine the corresponding mass concentrations of coarse particles and these values were then used to evaluate the diurnal variation both for fine and coarse particles. An indoor mass balance model was applied to estimate the aerosol mass emission rates, as well as the particle loss rates due to all removal processes. A good agreement was obtained between the model predictions and the measurements. The indoor model can be used in conjunction with experimental measurements for the evaluation of aerosol mass concentrations in industrial sites.