Lung cancer risk from PAHs emitted from biomass combustion.

This study deals with the assessment of the cancer risk attributable to PAH exposure, attributable to the increased use of biomass for space heating in Greece in the winter of 2012-2013. Three fractions of particulates (PM1, PM2.5 and PM10) were measured in two sampling sites (urban/residential and traffic-influenced) followed by chemical analysis of 19 PAHs and levoglucosan (used as a biomarker tracer). PAH-induced lung cancer risk was estimated by a comprehensive methodology that incorporated human respiratory tract deposition modelling in order to estimate the toxic equivalent concentration (TEQ) at each target tissue. This allowed us to further differentiate internal exposure and risk by age groups. Results showed that all PM fractions are higher in Greece during the cold months of the year, mainly due to biomass use for space heating. PAH and levoglucosan levels were highly correlated, indicating that particles emitted from biomass combustion are more toxic than PM emitted from other sources. The estimated lung cancer risk was non-negligible for residents close to the urban background monitoring site. Higher risk was estimated for infants and children, due to the higher bodyweight normalized dose and the human respiratory tract (HRT) physiology. HRT structure and physiology in youngsters favor deposition of particles that are smaller and more toxic per unit mass. In all cases, the estimated risk (5.7E-07 and 1.4E-06 for the urban background site and 1.4E-07 to 5.0E-07 for the traffic site) was lower to the one estimated by the conventional methodology (2.8E-06 and 9.7E-07 for the urban background and the traffic site respectively) that is based on Inhalation Unit Risk; the latter assumes that all PAHs adsorbed on particles are taken up by humans. With the methodology proposed herein, the estimated risk presents a 5-7 times difference between the two sampling sites (depending on the age group). These differences could not have been identified had we relied only on conventional risk assessment method. Consequently, the actual cancer risk attributable to PAHs on PM emitted from biomass burning would have been significantly underestimated.

[1]  C. Samara,et al.  Wintertime size distribution of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the urban environment: Street- vs rooftop-level measurements , 2009 .

[2]  S. Tao,et al.  Emission and Size Distribution of Particle-bound Polycyclic Aromatic Hydrocarbons from Residential Wood Combustion. , 2013, Biomass & bioenergy.

[3]  E. Stephanou,et al.  Occurrence of gaseous and particulate polycyclic aromatic hydrocarbons in the urban atmosphere: study of sources and ambient temperature effect on the gas/particle concentration and distribution. , 2005, Environmental pollution.

[4]  Risto Hillamo,et al.  Physicochemical characterization of fine particles from small-scale wood combustion , 2010 .

[5]  I. Nisbet,et al.  Toxic equivalency factors (TEFs) for polycyclic aromatic hydrocarbons (PAHs). , 1992, Regulatory toxicology and pharmacology : RTP.

[6]  Torben Nielsen,et al.  Traffic contribution of polycyclic aromatic hydrocarbons in the center of a large city , 1996 .

[7]  D. Dockery,et al.  Health Effects of Fine Particulate Air Pollution: Lines that Connect , 2006, Journal of the Air & Waste Management Association.

[8]  P. Masclet,et al.  Polycyclic aromatic hydrocarbons emitted by power stations, and influence of combustion conditions , 1987 .

[9]  Christer Johansson,et al.  Cancer risk assessment, indicators, and guidelines for polycyclic aromatic hydrocarbons in the ambient air. , 2002 .

[10]  M Brauer,et al.  Wood smoke exposure and lung adenocarcinoma in non-smoking Mexican women. , 2004, The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease.

[11]  T. Eck,et al.  A review of biomass burning emissions part III: intensive optical properties of biomass burning particles , 2004 .

[12]  Kai Zhang,et al.  Calculated respiratory exposure to indoor size-fractioned polycyclic aromatic hydrocarbons in an urban environment. , 2012, The Science of the total environment.

[13]  D A Sarigiannis,et al.  Exposure analysis of accidental release of mercury from compact fluorescent lamps (CFLs). , 2012, The Science of the total environment.

[14]  Yifang Zhu,et al.  Particle Deposition in Respiratory Tracts of School-Aged Children , 2014 .

[15]  S. Friedlander,et al.  Size distributions of polycyclic aromatic hydrocarbons and elemental carbon. 1. Sampling, measurement methods, and source characterization. , 1994, Environmental science & technology.

[16]  E. Manoli,et al.  Chemical characterization and source identification/apportionment of fine and coarse air particles in Thessaloniki, Greece , 2002 .

[17]  D Behera,et al.  Indoor air pollution as a risk factor for lung cancer in women. , 2005, The Journal of the Association of Physicians of India.

[18]  T. Prapamontol,et al.  PM10-bound polycyclic aromatic hydrocarbons in Chiang Mai (Thailand): Seasonal variations, source identification, health risk assessment and their relationship to air-mass movement , 2013 .

[19]  J. Seinfeld,et al.  Atmospheric Chemistry and Physics: From Air Pollution to Climate Change , 1997 .

[20]  D. Sarigiannis,et al.  Total exposure to airborne particulate matter in cities: the effect of biomass combustion. , 2014, The Science of the total environment.

[21]  C. Liao,et al.  Heavy incense burning in temples promotes exposure risk from airborne PMs and carcinogenic PAHs. , 2006, The Science of the total environment.

[22]  J. D. Mortensen,et al.  A numerical identification syterm for airways in the lung , 1983 .

[23]  F. Cassee,et al.  From concentration to dose: factors influencing airborne particulate matter deposition in humans and rats , 2003 .

[24]  G Thériault,et al.  Lung cancer mortality and polynuclear aromatic hydrocarbons: a case-cohort study of aluminum production workers in Arvida, Quebec, Canada. , 1994, American journal of epidemiology.

[25]  Wen-Jhy Lee,et al.  PAHs, PAH-induced carcinogenic potency, and particle-extract-Induced cytotoxicity of traffic-related nano/ultrafine particles. , 2008, Environmental science & technology.

[26]  M. Claeys,et al.  Identification and estimation of the biomass burning contribution to Beijing aerosol using levoglucosan as a molecular marker , 2008 .

[27]  M. Brauer,et al.  Woodsmoke Health Effects: A Review , 2007, Inhalation toxicology.

[28]  W Hofmann,et al.  Modeling techniques for inhaled particle deposition: the state of the art. , 1996, Journal of aerosol medicine : the official journal of the International Society for Aerosols in Medicine.

[29]  Philip K. Hopke,et al.  Critical review and meta-analysis of ambient particulate matter source apportionment using receptor models in Europe , 2013 .

[30]  A Gambaro,et al.  Sources of high PM2.5 concentrations in Milan, Northern Italy: molecular marker data and CMB modelling. , 2012, The Science of the total environment.

[31]  A. Cecinato,et al.  Annual variation of particulate organic compounds in PM10 in the urban atmosphere of Algiers , 2009 .

[32]  Mark J Nieuwenhuijsen,et al.  The EXPOLIS study: implications for exposure research and environmental policy in Europe , 2004, Journal of Exposure Analysis and Environmental Epidemiology.

[33]  Alexandre Caseiro,et al.  Wood burning impact on PM10 in three Austrian regions , 2009 .

[34]  Lowell L. Ashbaugh,et al.  Size distribution of polycyclic aromatic hydrocarbon particulate emission factors from agricultural burning , 2007 .

[35]  Athanasios Katsoyiannis,et al.  One year intensive PM2.5 bound polycyclic aromatic hydrocarbons monitoring in the area of Tuscany, Italy. Concentrations, source understanding and implications. , 2012, Environmental pollution.

[36]  M. Odman,et al.  Concentrations and sources of PAHs at three stations in Istanbul, Turkey , 2011 .

[37]  J. Klánová,et al.  Polycyclic aromatic hydrocarbons in background air in central Europe - Seasonal levels and limitations for source apportionment , 2012 .

[38]  Y. Liu,et al.  Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of Beijing. , 2008, Journal of environmental sciences.

[39]  Diana J. Freeman,et al.  Woodburning as a source of atmospheric polycyclic aromatic hydrocarbons , 1990 .

[40]  Ian M. Kennedy,et al.  The health effects of combustion-generated aerosols , 2007 .

[41]  W. Ott.  Concepts of human exposure to air pollution , 1982 .

[42]  M. Andreae,et al.  Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia , 2005 .