New Insights for Health and Environmental Impact Assessment of PM Released by Specific Emission Sources

This study is aimed to improve the knowledge about the association between health and environmental effects of particulate matter (PM) and its chemical composition and sources and it is focused on the integration of different observation systems and monitoring techniques. PM samples originated from different sources were collected and analyzed by traditional and innovative analytical methods, thus reaching a very detailed knowledge of their inorganic and organic chemical composition. (A) Acellular assays: 1,4-dithiothreitol (DTT), ascorbic acid (AA) and 2',7'dichlorodihydrofluorescein (DCFH), able to give information about PM capacity to generate oxidative stress, were applied to PM-selected components to estimate the oxidative potential (OP) of PM released by different emission sources (A1). Plant and animal model organisms were exposed in vivo under controlled conditions to the PM-selected components. Oxidative stress and other biological responses were evaluated and correlated to the OP and chemical composition of PM and the reliability of the OP methods as proxies of the production of reactive oxygen (ROS) and nitrogen (RNS) species was assessed (A2, A3). Furthermore, the potential of NO to restore the cellular balance between the ROS and the RNS in the root system of a plant species exposed to As and Cd was evaluated (A4). (B) To obtain valuable information for PM source apportionment and thus for the assessment of health and climate impact, a chemical/size fractionation method was applied to sampling campaigns carried out for seven consecutive years in the Po Valley (Northern Italy) (B1). PM10 and size-segregated PM samples collected in workplaces (B2) and in indoor environments of private dwellings (B3) were analyzed to investigate the health impact of particles emitted in different size fractions by specific indoor sources. (C) Innovative and very-low volume samplers were used for high spatial resolution analyses of PM chemical components in the Terni basin (Central Italy), which can be considered as an open air laboratory for studying the spatial distribution of PM, since it is characterized by atmospheric stability and by the presence of several anthropic PM sources (C1, C2, C3). The impact of local emission sources was assessed and the spatial variability of PM element concentrations was mapped (C3) and compared with the results achieved by biomonitoring through lichen transplants (C4) and leaf deposition on riparian species (C5), to verify the reliability of biomonitoring techniques for the assessment of atmospheric element concentrations. The experimental approach, based on the mapping of spatially-resolved PM chemical data, is a powerful tool for a reliable assessment of population exposure to PM air pollutants and also promises to be effective for optimization and validation of dispersion models. This approach, combined with on-site human biomonitoring will allow further investigations on the relationships between health effects and PM chemical composition and sources. (D) To investigate relationships between health effects and PM chemical composition and sources, the suitability of different biological matrixes for on-site human biomonitoring exposure to environmental pollution was evaluated. Rapid analytical methods for routine elemental analysis of a significant number of human hair samples were developed and validated (D1, D2). Moreover, Hg As, Pb and Cd levels in breast milk were assessed to provide valuable information on the maternal toxic load and to be used as an indicator for prenatal and post-natal exposure of infants to these chemicals. In addition, we assessed the capacity of a multi-strain probiotic to protect the infants from their exposure (D3). (E) Finally, during the PhD research, environmental remediation techniques for inorganic and organic pollutants were investigated. The potential of food waste materials as low-cost adsorbents for the removal of toxic elements, heavy metals (E1) and volatile organic compounds (E2, E3) from wastewater was evaluated. The adsorption capacity of food waste materials was assessed by comparing the removal efficiency of elements and VOCs from complex solutions, maintaining homogeneous experimental conditions, which allowed us comparing the adsorption capacity of the individual sorbents.