Expah - population EXposure to PAH
The Project
The European Community funded a project (EXPAH) by means of LIFE financial instrument, with the aim to identify and to quantify population exposure among children and elderly people to Polycyclic Aromatic Hydrocarbons (PAHs) content in particulate matter in highly urbanized areas and to assess the impact on human health, in order to support environmental policy and regulation in this field.
The project is based on an integrated approach where measurements, modeling techniques and epidemiologic investigations will be used to obtain estimation maps of population exposure to PAHs, to identify key determinants of high exposures including time-activity and locations in relation to the sources and to estimate potential health effects on the target population.
Background
Among Persistent Organic Pollutants (POP), Polycyclic Aromatic Hydrocarbons (PAHs) are a class of complex organic chemicals of increasing concern for their occurrence in the environment.
They are ubiquitous in ambient air and some of them have been identified as suspected carcinogens. PAHs can be found in the atmosphere in both gaseous and particulate forms (PM2.5 and PM10) in the atmosphere depending on their volatility which is governed by their chemical structure. The best known PAH is the benzo[a]pyrene (B[a]P).
PAHs and their derivatives are produced by the incomplete combustion of organic material: mainly from anthropogenic combustion and partially from biomass burning. In general there are five major emission sources of PAHs: domestic, mobile, industrial (including power generation and waste processing), agricultural and natural. In highly urbanized areas domestic heating and mobile sources, and specifically vehicles, are the largest contributors of PAHs, with diesel fuelled cars releasing higher particulate emissions than gasoline fuelled ones . As a consequence populations living in these areas are exposed to pollutants which have potential health effects. There is strong evidence for the relationship between PAH exposure and lung, skin, and bladder cancer in humans. DNA damage induced by PAHs exposure were demonstrated by different authors. Increase of genotoxic risk in people working in ambient urban air was also detected. Long-term exposure to PAHs has also been associated with gene mutation cell damaging and increased risks of cardiopulmonary mortality. Short term exposure has been reported to cause impaired lung function in asthmatic people and thrombotic effect in people affected by coronary heart disease.
The European Directive 2004/107/EC proposed a target value of 1 ng/m3 B[a]P for the total content in the PM10 fraction averaged over a calendar year. Furthermore this directive also suggests to assess the contribution of B[a]P in ambient air, as well as the indication for each Member State to monitor other relevant PAHs. . Moreover the PAHs, as POP, are found within the Italian National annual priority list for the year 2009, to develop base information supporting policy actions in the Environment and Health field (European action plan for Environment and Health 2004-2010). In the framework of Aarhus protocol on transnational air pollution (June, 24 1998), and specifically referring to persistent organic toxicant (see art. 8), actions are stimulated for the developing cooperative investigations to monitor and assess the health effects produced by persistent organic compounds.