Saharan dust levels in Greece and received inhalation doses

The desert of Sahara is one of the major sources of mineral dust on Earth, producing around 2×10 8 tons/yr. Under certain weather conditions, dust particles from Saharan desert get transported over the Mediterranean Sea and most of Europe. The limiting values set by the directive EC/30/1999 of European Union can easily be exceeded by the transport of desert dust particles in the south European Region and especially in urban areas, where there is also significant contribution from anthropogenic sources. In this study, the effects of dust transport on air quality in several Greek urban areas are quantified. PM 10 concentration values from stationary monitoring stations are compared to dust concentrations for the 4-year period 2003–2006. The dust concentration values in the Greek areas were estimated by the SKIRON modelling system coupled with embedded algorithms describing the dust cycle. The mean annual dust contribution to daily-averaged PM 10 concentration values was found to be around or even greater than 10% in the urban areas throughout the years examined. Natural dust transport may contribute by more than 20% to the annual number of exceedances – PM 10 values greater than EU limits – depending on the specific monitoring location. In a second stage of the study, the inhaled lung dose received by the residents in various Greek locations is calculated. The particle deposition efficiency of mineral dust at the different parts of the human respiratory tract is determined by applying a lung dosimetry numerical model, which incorporates inhalation dynamics and aerosol physical processes. The inhalation dose from mineral dust particles was greater in the upper respiratory system (extrathoracic region) and less significant in the lungs, especially in the sensitive alveolar region. However, in cases of dust episodes, the amounts of mineral dust deposited along the human lung are comparable to those received during exposure in heavily polluted urban or smoking areas.

[1]  G. Kallos,et al.  The Weather Forecasting System for Poseidon - an Overview , 2002 .

[2]  N. Pérez,et al.  A methodology for the quantification of the net African dust load in air quality monitoring networks , 2007 .

[3]  Nilgün Kubilay,et al.  Contributions of natural sources to high PM10 and PM2.5 events in the eastern Mediterranean , 2007 .

[4]  Robert J. Charlson,et al.  Perturbation of the northern hemisphere radiative balance by backscattering from anthropogenic sulfate aerosols , 1991 .

[5]  G. Kallos,et al.  Air pollution modeling in the Mediterranean Region: Analysis and forecasting of episodes , 2008 .

[6]  M. Vianaa,et al.  Spatial and temporal variability of PM levels and composition in a complex summer atmospheric scenario in Barcelona ( NE Spain ) , 2005 .

[7]  Barak Herut,et al.  Dry atmospheric inputs of trace metals at the Mediterranean coast of Israel (SE Mediterranean): sources and fluxes , 2001 .

[8]  Slobodan Nickovic,et al.  The Step-Mountain Coordinate: Model Description and Performance for Cases of Alpine Lee Cyclogenesis and for a Case of an Appalachian Redevelopment , 1988 .

[9]  H. Hansson,et al.  Speciation and origin of PM10 and PM2.5 in selected European cities , 2004 .

[10]  C. Perrino,et al.  Inorganic constituents of urban air pollution in the Lazio region (Central Italy) , 2007, Environmental monitoring and assessment.

[11]  C. Zender,et al.  Direct radiative forcing and atmospheric absorption by boundary layer aerosols in the southeastern US: model estimates on the basis of new observations , 2001 .

[12]  C. Perrino,et al.  Inorganic constituents of urban air pollution in the Lazio region (Central Italy) , 2008, Environmental monitoring and assessment.

[13]  G. Kallos,et al.  Transatlantic Saharan dust transport : Model simulation and results , 2006 .

[14]  C. Spyrou,et al.  Long-range transport of anthropogenically and naturally produced particulate matter in the mediterranean and North Atlantic : Current state of knowledge , 2007 .

[15]  X. Querol,et al.  Events affecting levels and seasonal evolution of airborne particulate matter concentrations in the Western Mediterranean. , 2003, Environmental science & technology.

[16]  W. J. Bair,et al.  The Revised International Commission on Radiological Protection (ICRP) dosimetric model for the human respiratory tract , 1991 .

[17]  G. Vali,et al.  Microbiology and atmospheric processes: the role of biological particles in cloud physics , 2007 .

[18]  I. Fung,et al.  Modeling of mineral dust in the atmosphere: Sources, transport, and optical thickness , 1994 .

[19]  Z. Levin,et al.  The Effects of Desert Particles Coated with Sulfate on Rain Formation in the Eastern Mediterranean , 1996 .

[20]  G. Kallos,et al.  A model for prediction of desert dust cycle in the atmosphere , 2001 .

[21]  G. Kallos,et al.  Saharan dust contributions to PM10 and TSP levels in Southern and Eastern Spain , 2001 .

[22]  R. Hillamo,et al.  Size-segregated mass distributions of aerosols over Eastern Mediterranean: seasonal variability and comparison with AERONET columnar size-distributions , 2007 .

[23]  C. Zender,et al.  Mineral Dust Entrainment and Deposition (DEAD) model: Description and 1990s dust climatology , 2003 .

[24]  M. Schulz,et al.  Role of aerosol size distribution and source location in a three‐dimensional simulation of a Saharan dust episode tested against satellite‐derived optical thickness , 1998 .

[25]  Gregory R. Carmichael,et al.  Photochemical Oxidant Processes in the Presence of Dust: An Evaluation of the Impact of Dust on Particulate Nitrate and Ozone Formation , 1994 .

[26]  R. J. Lorenz.  Weibel, E. R.: Morphometry of the Human Lung. Springer Verlag, Berlin‐Göttingen‐Heidelberg 1963; 151 S., 109 Abb., DM 36,‐ , 1966 .

[27]  Slobodan Nickovic,et al.  An Alternative Approach to Nonhydrostatic Modeling , 2001 .

[28]  Mihalis Vrekoussis,et al.  Origin and variability of particulate matter (PM10) mass concentrations over the Eastern Mediterranean , 2006 .

[29]  D. Dockery,et al.  Acute respiratory effects of particulate air pollution. , 1994, Annual review of public health.

[30]  Mar Viana,et al.  Speciation and origin of PM10 and PM2.5 in Spain , 2004 .

[31]  L. Mona,et al.  Systematic lidar observations of Saharan dust over Europe in the frame of EARLINET (2000-2002) , 2008 .

[32]  C. Venkataraman,et al.  ESTIMATING THE LUNG DEPOSITION OF PARTICULATE POLYCYCLIC AROMATIC HYDROCARBONS ASSOCIATED WITH MULTIMODAL URBAN AEROSOLS , 1998 .

[33]  Z. Janjic.  The Step-Mountain Eta Coordinate Model: Further Developments of the Convection, Viscous Sublayer, and Turbulence Closure Schemes , 1994 .

[34]  D. Griffin,et al.  Atmospheric transport of mold spores in clouds of desert dust. , 2003, Archives of environmental health.

[35]  G. Kallos,et al.  Synoptic and mesoscale weather conditions during air pollution episodes in Athens, Greece , 1993 .

[36]  Xavier Querol,et al.  PM10 and PM2.5 source apportionment in the Barcelona Metropolitan area, Catalonia, Spain , 2001 .

[37]  M Lippmann,et al.  Deposition, retention, and clearance of inhaled particles. , 1980, British journal of industrial medicine.

[38]  G. Kallos,et al.  Forecast errors in dust vertical distributions over Rome (Italy): Multiple particle size representation and cloud contributions , 2007 .

[39]  Christos Housiadas,et al.  Eulerian modelling of lung deposition with sectional representation of aerosol dynamics , 2005 .

[40]  A. Sunnu,et al.  A long-term experimental study of the Saharan dust presence in West Africa , 2008 .

[41]  Soon-Ung Park,et al.  Aerosol size distributions observed at the Seoul National University campus in Korea during the Asian dust and non-Asian dust periods , 2006 .