Abstract
Changing climate is an intrinsic characteristic of the Earth's system. However, past changes have rarely been as quick as nowadays, with human influence playing a key role. Human-caused greenhouse gases (GHG) are leading to an increase of the global temperature, which is usually known as climate change. In turn, changes in some environmental parameters, such as temperature and solar radiation, are likely to influence the fate and transport of persistent organic pollutants (POPs) as well as other organic chemicals. The present study aims at evaluating the effect of climate change on the photodegradation of polycyclic aromatic hydrocarbons (PAHs) in soils. Samples of soils with different characteristics (Latosol, Neosol, Nitosol and Vertisol) will be collected from the A horizon of several areas of Catalonia (Spain) and São Paulo state (Brazil). They will be subjected to different temperature and UV-light radiation conditions in a Binder KBWF 240 climate chamber (Binder GmbH, Tuttlingen, Germany). Two climate scenarios will be considered according to IPCC projections: 1) a base (B) scenario, being temperature and light intensity 20°C and 9.6 W/m2, respectively, and 2) a climate change (CC) scenario, working at 24 °C and 24 W/m2, respectively. Photodegradation rates will be studied by comparing the decrease of PAHs in the different soils with respect to dark controls, which will be subjected to the same conditions of temperature but lacking light. The PAH photodegradation study will be complemented by the identification of PAH metabolites, potentially generated during the experiment. Finally, an hydrogen isotope analysis of marker PAHs, namely naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, pyrene and benzo(a)pyrene, will be conducted to confirm their photodegradation. The study will be open to analyses soil samples from other locations worldwide through the collaboration with other potentially interested international partners. (AU)
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