Institute of Atmospheric pollution Research (IIA)

Research activities

Research Activities

Research activities at the Institute have always been aimed at understanding the mechanisms underlying pollutant formation, transformation, and deposition, and at developing new methods of environmental assessment and analysis.

Yet, due to the presence of large number of contracts and agreements, the Institute has allocated a considerable amount of time and energy toward applied research and service activities. Despite these challenges, the Institute has made use of the resources available to formulate provocative research questions and make substantial research contributions. Consequently, even when the climate for research in Italy was less than favorable, the Institute was able to obtain impressive scientific results, which allowed for a continuation of our tradition of excellence, both nationally and internationally. Maintaining this balance between service and research will be the blueprint for future research activity, so that the Institute will be able to manage internal responsibilities and not be limited by external events.

One of the Institute's primary areas of research focuses on one of the fundamental mechanisms of photochemical pollution, its precursors. By pursuing species that originate from photochemical reactions, we investigate their distribution over space and time. In particular, our continued study of the formation of nitrous acid has shed new light on the process in which free radicals form in the atmosphere, how they form photochemical pollutants, and/or how they proceed to remove substances from the atmosphere, with negative consequences for the environment. Building upon research conducted previously, we have had the opportunity to study and assess the basic formation mechanisms of nitrogen oxides, and their surface reactions with water. These formation mechanisms, previously unknown, have allowed us to accurately interpret the most important photochemical pollution phenomena occurring in major urban centers, demonstrating that it is possible to calibrate appropriate chemical-physical models and then apply them to successfully describe said phenomena. The importance of this research is multifaceted, in the sense that it has allowed for deeper investigation into the relationship between air pollution and local weather and climate processes. By applying our observations regarding the presence and temporal distribution of radon and its progeny, we were able to improve descriptive models relating to atmospheric stability. Moreover, the use of neural networks has been decisive in allowing us to accurately estimate the temporal behavior of air pollution. In understanding the meteorological parameters associated with atmospheric stability, we were able to completely separate meteorological variables from emissions, providing an important tool for planning air-quality remediation. In addition, we have applied this aspect of the research to secondary pollutants, as this fits within the Institute's larger research focus on managing air pollution in large urban areas of maximum public exposure.

This research has also made an important contribution to our understanding of flow reactor techniques in determining the kinetic constants of surface reactions. Physical adsorption and chemical formation are two very important processes in understanding air-quality in urban and "indoor" environments, both of which are characterized by high surface/volume ratios. In these cases, the transfer kinetics between gas molecules and surfaces are critical to their subsequent chemical and physical evolution or transformation. In this context, continuing to develop techniques that characterize surfaces and their photo-catalytic properties acts as a practical step in facilitating the removal of air pollutants.

Another of the Institute's important contributions has been the improvement of instrumental techniques that measure specific pollutants. Among these is a new tool based on liquid chromatography and fluorescence detection, used in determining micro-traces of nitrous acid. This particular instrument, when modified and adapted appropriately, is not only important in understanding the atmospheric chemistry of urban areas but also in remote environments (this instrument has a detection limit that is of the order of parts per trillion, ppt). We carried out this ambitious plan in the city of Parma, where we developed new instrumentation both to characterize new sensors for measuring air pollution and for using these sensors in the direct measurement of vehicular and highway pollution.

Among the products formed in photochemical reactions, organic substances that contain carbonyl groups (such as aldehydes and ketones) play an increasingly important role, not only by indicating the origins of polluted air masses but as elements that define atmospheric reactivity. Recent studies on the evolution of these species have led to the development of techniques able to perform measurements for large numbers of gas phase and semi-condensed phase compounds simultaneously. In this case, we employed high-pressure liquid chromatography, an analytical technique that marked a breakthrough in how analytical chemistry is applied to the environment.

The evolution of global and regional observing systems in the framework of the GEO (Group on Earth Observation) in support to GEOSS program has been the main driver for developing a new research activity within the institute aiming to develop advanced sensor for air pollution monitoring based on nano composite materials characteristics, nano technology and micro electronics. The overall aim is to develop new sensors that are much less expensive, not requiring significant power (< 100 Watts) and maintenance, and suitable to design citizen's observatories for environmental monitoring. the latter is the main goal of H2020 and has been the key emerging topic in the last phase of FP7. This activity is also aimed to support SMEs to be more competitive on emerging markets. Recent emerging market analysis performed by several international organizations (i.e., World Bank) highlights that the future world market in environmental monitoring sensors is between 10-20 Billion USD for the period 2015-2025. Therefore the Institute objective is also to develop a new generation of advanced sensors for major atmospheric pollutants that are equivalent to reference methods and reference technologies approved in EU as part of CEN activities.

The Institute has also continued to conduct research on new passive samplers by studying the rate of absorption as a function of fluid dynamics in the atmosphere, particularly with regard to efficiency across different weather variables. In the process, we have developed samplers for chemicals never used previously, including ammonia, and more recently, carbon dioxide. Utilizing passive diffusion, we developed innovative techniques for measuring both carbon dioxide concentrations and isotopic ratios, an innovation that holds great promise for understanding the greenhouse effect and making a significant contribution to the study of global change. In pioneering these measurement methods, the Institute has contributed to the development of passive systems that can reduce the environmental impact of air pollutants by managing their different components. This approach, deemed "intelligent traffic," was widely appreciated internationally, which led to an invitation for the Institute to lay the groundwork for a project managing pollutant traffic at the XIX Commonwealth Games of 2010, in New Delhi.

The Institute's continued research on atmospheric particulates containing carbon has successfully distinguished between the various contributors, including those from both diesel traffic and natural aerosols, which constitute most regional pollution in major urban areas. All of this research was conducted at the Villa Ada Research Station in Rome. This facility, in conjunction with another in Montelibretti that focuses on background pollutants, allowed us to study the transport of pollutants from their sources to areas outside of the city. In this regard, a shortage of relevant data has made it essential to initiate research projects that assess the quantity of pollutants emitted from diesel engines. As a result, we have developed criteria for both sampling and analyzing emissions, and for characterizing various abatement instruments.

Of particular interest is our line of research that has characterized Cocaine (and other drugs) in the atmosphere of urban areas, a subject that has garnered considerable social interest. This successful research project largely depended on the availability of a specialized research infrastructure, like the mass spectrometer, which allowed us to understand highly complex organic mixtures. These techniques have also been used to characterize sediment and other samples of marine origin. The chemical characterization of particulate matter and its relation to the evolution of atmospheric aerosols is a field in which the Institute has continued to play a prominent scientific role. Given the complexity of aerosols and their importance not only for air pollution, but also for their role in developing the mechanisms of global climate change, their complete characterization is a highly important area of research. In this regard, we have paid close attention to measuring concentrations of PM10 and PM2.5, in light of the environmental risks they incur.

The chemical composition of such granulometric fractions can show characteristics that reveal their origins, when such a revelation is possible. In particular, we have conducted studies evaluating natural contributions to concentrations of particulate matter (Saharan dust, sea spray). The recent acquisition of an X-ray fluorescent spectrometer and an electron microscope has enhanced our laboratory facilities for research in this area. The study of particulates is attracting great scientific and practical interest, and in this regard, we have found an immediate, international context for our intensive scientific campaign on nanoparticles. The presence of these particles has had a significant influence on the development of waste-incineration techniques throughout Italy, yet little is known about their spatial and temporal distribution.

Yet, this impetus for chemical-analytical research has not impeded the scientific and technical development of other disciplines at the Institute. In this regard, the most important program examines a new approach for monitoring air quality using active sensors, in real time, with a large number of monitoring stations in any given area. Fixed stations, normally used for assessing atmospheric pollution in urban or industrial areas, have inherent limitations in their ability to acquire data with higher spatial and temporal resolutions. To account for this limitation, we have organized new projects that utilize mobile or temporary monitoring stations. For example in the city of Parma, we employed this new approach to collect information essential to the characterization of pollution from vehicular traffic, an urban/industrial monitoring project that could be the best response to the needs of developing and developed countries alike, including those preparing to join the European Union. This approach is now used in implementing traffic management systems, in relation to air pollution in urban areas.

Also noteworthy is our line of research that uses the MIVIS multispectral detector, an instrument that is known to be well suited to collecting environmental-themed terrestrial observations. This spectrometer is deployed in airplanes that fly over the area being studied and it works in conjunction with field-surveys that collect data on the ground. The utility of the MIVIS spectrometer is in comparing the data and assessing the instrument's response. Our use of the MIVIS spectrometer with these concurrent remote sensing techniques has spurred interest in this type of research methodology, as this approach has opened up possibilities for evaluating parameters relating to biodiversity and other natural phenomena. We are in the process of achieving these objectives by developing suitable, functional, interpretive, models. These ecological and environmental models are capable of being deployed on a national scale, when little is known about an area's topography, ecology, or atmospheric composition. The research is being conducted in areas of elevated environmental risk, to better understand the consequences of illegal waste disposal. We conducted parallel studies that examined the possibility of obtaining similar information by satellite, but satellite-campaigns did not offer the same spatial resolution or spectral capacity. The successful conclusion of this research could open interesting opportunities in applying hyperspectral techniques to areas where direct observations of biodiversity may prove to be too difficult. In using these remote-sensing techniques, we continue to integrate ground-based research observations with those that are collected remotely. This has opened a channel of research focused on the integration of measurement techniques for data collected over differing degrees of temporal and spatial resolution, and we have adapted this approach to characterize those environmental sites most at risk from air pollution (such as steel factories and power plants).

Remote sensing has also been applied to other fields, including historic preservation. For a number of years, the Institute has sponsored studies of art preservation and corrosive materials, both for artifacts exposed to the atmosphere and those exhibited in museums. This research has focused on characterizing the interactions between reactive gaseous substances and surfaces, a line of inquiry that led to the development of passive samplers. Hyperspectral remote sensing techniques have also aided the practice of cultural preservation by predicting what might be found underground. Spectral anomalies, one type of instrumental response, can indicate when buried artifacts might be present.

Studies that use remote sensing to characterize environmental factors have been vitally important in understanding the eco-physiological parameters of vegetation. These studies attempt to understand how vegetation mitigates the accumulation of carbon dioxide in the lower layers of the atmosphere, and which factors determine the formation of biomass. Just as in prior studies, this research not only aims to characterize these systems, but also to offer a more effective conservation of forest resources; to protect these ecosystems from wildfire, deforestation, and disease.

The use of hyperspectral techniques has also led to notable advances in our understanding of architectural and environmental features of large urban areas. The high spectral resolution offered by the MIVIS detector has allowed us to study the roofs of buildings, including those with asbestos-cement. Asbestos-based rooftops effect the distribution of heat in urban areas, and they cause many environmental problems by emitting mineral fibers that are dangerous to human health.

Also noteworthy is the amount of scientific work we have undertaken to characterize marine environments. The marine environment is characterized by simultaneously being both the source and ultimate fate of atmospheric pollutants. Consequently, the Institute is investigating a number of different scientific questions relating to coastal and marine environments. These studies focus on the presence of nutrients and phytoplankton distribution, and on mercury contamination in the Mediterranean (on both continental and global scales) and polar environments--a subject notable for its environmental importance and by the absence of adequate knowledge about it.

Mercury offers the best example of how the sea can be a source of air pollutants, because we know that mercury is emitted in large quantities from the oceans (as well as from urban and industrial anthropogenic emissions). This phenomenon determines emission factors that are of interest to everyone in the Mediterranean area, and research has been conducted to establish its spatial, temporal, and chemical distribution. Mercury is present in several chemical species of varying toxicity that are transformed into one another. To clarify the mechanisms that underlie the biogeochemical cycling of mercury, we conducted experimental campaigns in both urban and remote areas, such as the Arctic. Recently, we launched a major European project aimed at building a global observation system to monitor mercury pollution in the oceans, atmosphere, and troposphere. The GMOS project (Global Mercury Observation System,, coordinated by the Institute's Rende Group, was planned to support both the preparation of an International Treaty on Mercury (within UNEP) and the GEOSS program in the context of the GEO work plan (2012-2015).

Technologies developed through the study of mercury have been put to proper use in understanding persistent organic pollutants (POPs), which are an environmental problem on a global scale. Therefore, developing techniques in relation to dynamic interactions between atmosphere and sea surface is fundamental to understanding various environmental problems.

The chemical interaction between the atmosphere and surface ecosystems is undoubtedly one of the main areas of research pursued in the Institute. As already mentioned, this subject will be of great importance in protecting works of art and for the study of pollutant cycling. Similarly, we have conducted studies of polar areas to assess interactions between nitrogen oxides and snow-covered surfaces, which first combine to form nitrous acid and then form free radicals in the polar atmosphere. These studies were performed by measuring the fluxes of the various gaseous components using micro-meteorological techniques and high-precision measurement devices. To do so, we examined reactions involved in the heterogeneous formation of nitrogen oxides, including those that occurred on the surfaces of aerosols. In addition, we characterized these aerosols both chemically and physically. Experimental campaigns were also conducted in both the Arctic and Antarctic. These campaigns brought the highest levels of international acclaim to the Institute, with respect to this research area. Pollution from compounds containing nitrogen is one of the primary areas of focus for studying hemispheric pollution. The nitrogen cycle, which begins with nitrogen monoxide, is an important component.

In the field of industrial research, we have put into place systems to measure and evaluate industrial pollution and its effects on the environment, particularly in reference to chlorine-containing compounds, such as dioxins and furans. Great attention has been given to heavy metals and the role they have in the relationship between environment and human health. In this regard, we are continuing investigations on the major sources of dioxin and other persistent organic pollutants (POPs).

Finally, it is fairly clear that the Institute has had not only a cultural effect on the country, but an economic and social one as well. We need hardly to mention our contributions in the development of new measuring devices, the monitoring and optimization of detection systems in support of emission control technologies, and the reduction of air pollutants from industrial sources. The study of pollution in large urban areas has led to significant advances in reducing municipal emissions, while remote sensing activities have made a very important contribution to the Ministry of Defense's efforts to combat illegal activity, environmental and otherwise.