HICE and aeroHEALTH

Characterization of Reactive Organic Compounds in Gases and Particulate Matter

In WP I, aerosols from a variety of anthropogenic sources and model aerosols are characterized with respect to reactive organic compounds and made available for exposure experiments.

The composition of the pollutants depends strongly on the geographical location and atmospheric conditions and is therefore difficult to interpret. Therefore, emissions from typical anthropogenic combustion sources will be studied. The consortium has extensive experience in operating emission sources and sampling systems. A wide range of technical equipment is available at the University of Western Finland and the University of Rostock: Boiler burners, test setups for automotive engines and marine diesel engines. Flame soot and ash particles are produced for tests and standard reference measurements. Modern fuel formulations (biofuel), which are known to have higher oxygen content, are taken into account.

Modern methods of mass spectrometry and measurement techniques for chemical and physical processes are used to comprehensively characterize the emission aerosol. Mass spectrometric methods are additionally adapted to characterize the biological response. 

Both resonance-enhanced multiphoton ionization and single photon ionization form the basis for the mass spectrometric methods.

For the analysis of aerosols, gas and particle phases are combined, but also used separately to account for the fact that reactive organic compounds often occur in a gaseous fraction as vapor in the gas phase, but also as a liquid or solid fraction condensed on the aerosol particles.

The reactive organic compounds (ROC) in the gas phase of the aerosol are characterized by photoionization mass spectrometry, and the particles are characterized by aerosol time-of-flight (ATOF) mass spectrometry. In addition, physical parameters of the particles such as number and mass concentration are determined online. Both the particles and the gas phase will be collected and made available for offline analysis in WP III.
 
During the ongoing work, the analytical focus will be shifted to the potential recurring markers based on the results obtained in WP II and WP III. The goal is an emission assessment based on (bio-)statistical approaches combining the results from WP I with those of the analytical approaches in WP II and WP III.

Health effects and toxicology of reactive organic compounds in aerosols

In WP II, the biological effects of the freshly generated combustion aerosol, the particulate phase alone (stripped with gas phase dust collectors), and the gas phase alone (filtered) are comparatively studied in human cell systems. Cells will be exposed to the aerosol both in vitro and in an exposure facility at the air-liquid interface. In co-cultures, up to five cell types will be combined to form a differentiated human lung tissue model. In vivo studies will translate the results to human samples. The biological effects in cell cultures and tissues will be studied at all hierarchical levels (genome, transcriptome, proteome and metabolome).

Since the emission sources are heavy stationary structures (test benches for diesel and gasoline engines, marine engines and boilers), test aerosol generators and exposure systems will be mobile. All working groups involved in the HICE virtual institute will meet for several large-scale tests at the different sites in Europe.

The biological effects are investigated jointly with WP III. The biological endpoints are therefore e.g. cytotoxicity, metabolic activity, determination of functions, oxidative stress and inflammatory response markers. In addition, non-targeted effects will be investigated e.g. using genome-wide gene expression, protein profiling and induction analyses. In selected experiments, stable isotope labeling is used to perform flux analyses in the proteome and metabolome.

Clinical partners provide human cells and tissues from lavages, biopsies, or pathological examinations of healthy and diseased individuals to screen for biomarkers found in laboratory experiments.
In collaboration with WP IV, the data will be analyzed and screened for biomarkers associated with exposure and harm.

Comprehensive chemical analysis of small molecules in aerosols and biological systems

This work package focuses on comprehensive chemical analysis. On the one hand, this is the characterization of the chemical composition of the different aerosol compartments. On the other hand, it is the study of the effects of chemically and physically well characterized aerosols on biological test systems and their possible health effects. Therefore, the changes in the pattern of small molecules in biological test systems caused by exposure to aerosols will be investigated.

Within HICE, there is a strong body of knowledge related to the chemical analysis of organic constituents of aerosols. A wide range of mass spectrometric and chromatographic techniques have been established (LC, GC, TOFMS, FTMS, MALDI imaging). Much research has been done to facilitate quantitative analysis of large time series and analysis of selected marker compounds. In recent years, concepts for comprehensive chemical profiling (GCxGC) and isotopic labeling "non-targeted tracer fate detection (NTFD)" have been developed and applied to environmental and/or biological applications. The NTFD concept is applied to cell cultures to study the effects of aerosols on biological systems. In a second step, the NTFD methodology is combined with comprehensive two-dimensional gas chromatography (GCxGC).

Targeted and non-targeted methods will be used to reveal the complex chemical composition of the aerosol matrices from WP I as well as the biological system from WP II. FTMS and IRMS systems are used for marker identification and chemical profiling of aerosols and biological systems. Specific tools for data analysis will be developed in close collaboration with WP I and IV. To identify similarities and correlations between gas and particle phase species and their potential interactions, analytical results will be investigated and interpreted in conjunction with on-line data from WP I.

Scientific data management, chemometrics and biostatistics

WP IV is the central interface within the HICE. It is responsible for the combined statistical data analysis, which includes all analytical work packages (WP I-III).

First, it has to set up and monitor the data management of all scientific data. Besides this permanent setup, WP IV supports the different projects within the WPs with the "Design of Experiments (DOE)" to ensure the applicability of the statistical methods and the documentation of the experiment. A third task is the central analysis and evaluation of the scientific data and a basic consistency check. For a comprehensive analysis of the data, the results from the working groups will be
and within and between the working groups are combined into a biostatistical analysis.

The data from all measurement campaigns and exposure experiments will be statistically evaluated and comprehensively interpreted with regard to possible biomarkers for aerosol-related health effects.