Abstract: The majority of researchers, conservators and curators recognise that atmospheric pollution is one of the major threats to works of art. In principle, all atmospheric particles, when deposited onto art objects can be considered harmful because of their potential in causing deterioration. Moreover, under certain conditions, particulate matter can induce and intensify surface damage, particularly because of its potential to serve as centre for moisture condensation and adsorbent of gaseous pollutants. To investigate the potential harm that these particles can cause, comprehensive characterisation of the particulate matter is necessary. Particulate matter was collected at the Rubens' House Museum in Antwerp, Belgium, where a unique exhibit of the paintings and living quarters of Peter Paul Rubens (1577-1640) are seen. Size segregated aerosol samples were collected for analyses of bulk and single particle elemental and molecular compositions. They were analysed by electron probe micro-analysis, utilising facilities for low-Z element determination, and by energy-dispersive x-ray fluorescence, to investigate the elemental composition of individual particles and bulk samples, and by micro Raman spectrometry, to elucidate the molecular composition. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could contribute to the chemical reactions taking place on the surfaces of artefacts and which could potentially cause degradation of the objects.

Abstract: The advances in the characterization of amorphous carbons by Raman spectroscopy over the last four decades are of interest to many industries, especially those involving the combustion, gasification and pyrolysis of coal. Many researchers report on the Raman character of the natural organic matter in carbon-containing compounds, such as coal, and relate the Raman bands to the structural order of the amorphous carbons. The basis of most of these studies evolved around the assignment of the G (graphitic, ∼1580 cm−1) band to crystalline graphite and any other bands, called D bands, (disorder, various from 1100 to 1500 cm−1) to any type of structural disorder in the graphitic structure. Concerning coal analysis, the information gained by Raman investigations has been used to describe char evolution as a function of temperature, the presence of catalysts and different gasification conditions. In addition, researchers looked at maturation, grade, doppleritization and many more aspects of interest. One aspect that has, however, not been addressed by most of the researchers is the natural inorganic matter (NIM) in the carbon-containing compounds. Micro-Raman spectroscopy (MRS) has many advantages over other characterization tools, i.e. in situ analysis, nondestructive, no sample preparation, low detection limit, micrometer-scale characterization, versatility and sensitivity to many amorphous compounds. With the distinct advantages it has over that of other molecular characterization tools, such as powder X-ray diffraction (PXRD), Fourier-transform infrared spectrometry (FT-IR) and scanning electron microscopy with X-ray detection (SEM/EDS), it is surprising that it has not yet been fully exploited up to this point for the characterization of the NIM in coal and other amorphous carbons. This paper reviews the work published on the Raman characterization of the natural organic matter (NOM) of coals and reports on preliminary results of the NIM character of various South African coals, whereby various inorganic compounds and minerals in the coal have been characterized.

Abstract: In the past years, and also within the framework of this CRP, we have used a combination of several nuclear and non-nuclear techniques in fundamental research and especially in various applications. Most work has been done with energy-dispersive X ray fluorescence in combination with electron probe X ray microanalysis, but several other more common analysis techniques have been used as well. The applications have included mostly preventive conservation (e.g. characterisation of damaging atmospheric particles in many museums) and environmental monitoring (e.g. for atmospheric particles in relation to their health effects in outdoor and especially indoor environments). Fundamental aspects have been in the optimising of interfaced electron microprobe and Raman microprobe analysis and the evaluation of the potential of such an instrument for atmospheric aerosols; quite a few unexpected and unpredicted problems have appeared in the latter study.

Abstract: The risk profile of Cr and Pb in urban road deposited sediment Exponential urbanisation and industrial growth occur on a global scale and result in an ecological burden, of which one important part is pollution. It is well known that the extent of air pollution has escalated over the past two decades in several parts of the world, despite mitigating measures and legislation. Current research points to the fact that air pollution in urban and industrial areas is substantially different from that found in rural areas. Road dust (RD) contributes up to 35% of airborne particulate matter due to resuspension thereof, and poses a health concern due to carcinogenic and toxic components potentially present in the micron-sized fractions. Although literature does report on the concentrations of trace, toxic metals and metalloids present in RD (Hooker and Nathanail 2006), the molecular make-up of particulates generated due to the resuspension of the RD is not well documented. In vitro and animal toxicological studies have confirmed that the chemical composition of inhaled particles plays a major role in its toxic, genotoxic and carcinogenic mechanisms, but the component-specific toxic effects are still not understood. Transition metals binding to air particle matter can result in reactive oxygen species in the human body (particularly in the lungs), and this is a significant risk, especially for vulnerable population groups like elderly people, children and terminally ill patients. The characterisation of the molecular composition of the fine fraction is evidently of importance for public health. During an earlier study, road dust from an inner-city environment in the UK was collected and partially characterised (Barrett e.a. 2010). These same-size fractions were analysed for their elemental concentrations, using X-ray Fluorescence Spectrometry (XRFS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In addition, single-particle analysis was performed on the different fractions by means of Computer Controlled Electron Probe X-ray Micro Analysis (CC-EPXMA) and their molecular structure probed by studying elemental associations. These findings were correlated with Micro Raman Spectroscopy (MRS) results. It was found that the fine fraction (<38 μm) had the highest Pb (238 ppm) and Cr (171 ppm) concentrations. The CC-EPXMA data showed >50% association of Cr-rich particles with Pb and the MRS data showed that the Cr was mostly present as lead chromate and therefore in the Cr(VI) oxidation state. Concentrations of both Pb and Cr decreased substantially (279 (<38 mm) 13 ppm (<1mm); 171 (<38 mm) 91 ppm (<1mm) respectively) in the larger fractions. Apart from rather alarmingly high concentrations of oxidative stressors (Cu, Fe, Mn), the carcinogenic and toxic potential of the inhalable fraction is evident. Preliminary bioaccessibility data indicated that both Cr and Pb are readily