Catálogo de publicaciones - libros

Automobile exhaust catalysts were introduced in the US in the mid-1970s to reduce traffic-derived air pollution in urban areas, and have resulted in significant air quality improvements. It has however been demonstrated that a small amount of platinum group elements, the main active components in catalysts, are emitted during vehicle operation (Konig et al., 1992; Palacios et al., 2000; Moldovan et al., 2002) resulting in elevated concentrations of these normally rare metals in the urban and roadside environment (Gomez et al., 2002). While these metals were believed to remain in the urban and roadside environment, recent studies have suggested the possibility for regional and global dispersion of these elements.

A 2-year project with the co-authors as partners and funded by the Alliance for Global Sustainability was initiated in 2002 to provide a further understanding of PGE transport from roadside environments. This paper presents literature and project-related information on potential regional and long range transport, from automobile catalysts to global distribution.

The distribution and behaviour of anthropogenic platinum-group elements (PGE) in river systems has as yet attracted little attention. Aquiring good quality data in PGE analysis poses a serious challenge to the environmental chemist, not in the least due to the low concentrations at which the PGE are currently found in the environment. Using the River Stour in Kent, U.K. as a case study, the work presented in this paper focuses specifically on the spatial and temporal variability of PGE in fluvial sediments. The analysis of river bed sediments shows high variability both on a catchment scale and on a local scale within sample sites. Moreover, high relative standard deviation points to a heterogeneous distribution of PGE within sediment samples, which is characteristic of the elements and is commonly known as the nugget effect. If unassessed, analytical data are unlikely to be truly representative and the interpretation of PGE data could be inherently flawed. For this reason this paper suggests a need to include thorough quantification and reporting of this variability as a matter of practice in the acquisition of environmental PGE data.

Palladium and other precious metals such as platinum, and rhodium are emitted to the environment due to autocatalysts. Besides this, other emission sources such as dental alloys, cancer drugs, jewellery and petrochemistry amount extensively and are part of the total PGE contamination in sewage sludge. The amount of PGE related to automobile catalysts can be defined by the Pt/Rh ratio of 5 to 6 and by the Pt/Pd ratio of 0.8. Due to the various sources and the mixture of the contaminants the ratio gets changed considerably so that further trace metals are needed for source identification. The emission of Pd is increasing in the last years due to higher Pd consumption especially as substitute for Pt in converters.

Sewage sludge as matrix which generally accumulates human consumables was selected for this study. Sewage sludge samples of various waste water treatment plants (WWTPs) in Switzerland were analysed and can be grouped into three different types. Type A represents waste water from households of villages with a Pd/Pt ratio of up to 3.8 and type B a mixture of domestic waste water and street runoff of villages and small towns with varying Pd/Pt ratios. WWTPs of Type C receive a mixture of the sources mentioned above plus industrial waste water exhibiting a lowest Pd/Pt ratio of around 1 and a Pt/Rh ratio of up to around 20 reflecting industrial influx. For source identification further trace elements (Zr, Rb, Cd, Zn, Cu, Ni, Ti, Pb, Sb) were chosen and evaluated by cluster analyses. Seven different clusters could be identified underlining the Pd, Pt and Rh content as traffic induced.

Palladium (Pd), Platinum (Pt) and Gold (Au) were analysed in 598 terrestrial moss and 617 O-horizon samples from a 188,000 km-area surrounding several plants within the Russian nickel industry on the Kola Peninsula. At the time of the survey ore from the Noril’sk deposits in Siberia, which has high concentrations of platinum group elements (PGE), was processed in the Monchegorsk smelter. In contrast, the smelter in Nikel and the ore roasting plant in Zapolyarnij processed predominantly local Pechenga ore, which has low PGE and Au-concentrations. Moss and O-horizon samples were analysed by a method using reductive co-precipitation to enrich PGE and Au prior to analysis. Unusually low detection limits could be reached (Au: 0.05 ppb, Pd 0.1 ppb and Pt 0.3 ppb), allowing the construction of reliable regional geochemical maps. Maps and transects demonstrate the impact of the smelters on the arctic environment. Differences in the ore feed are well reflected in the emissions. Although the Kola smelters belong to the most important PGE-emitters on earth, background concentrations for all three elements are reached at a distance of less than 200 km from source. Several geogenic anomalies highlight the further exploration potential of the area for Au and PGE-deposits. Results can also be used to calculate approximate emission figures for the Monchegorsk smelter (0.1 t Au, 2.2 t Pd and 0.8 t Pt per year).

The distribution and behaviour of anthropogenic platinum-group elements (PGE) in river systems has as yet attracted little attention. Aquiring good quality data in PGE analysis poses a serious challenge to the environmental chemist, not in the least due to the low concentrations at which the PGE are currently found in the environment. Using the River Stour in Kent, U.K. as a case study, the work presented in this paper focuses specifically on the spatial and temporal variability of PGE in fluvial sediments. The analysis of river bed sediments shows high variability both on a catchment scale and on a local scale within sample sites. Moreover, high relative standard deviation points to a heterogeneous distribution of PGE within sediment samples, which is characteristic of the elements and is commonly known as the nugget effect. If unassessed, analytical data are unlikely to be truly representative and the interpretation of PGE data could be inherently flawed. For this reason this paper suggests a need to include thorough quantification and reporting of this variability as a matter of practice in the acquisition of environmental PGE data.

Automobile exhaust catalysts were introduced in the US in the mid-1970s to reduce traffic-derived air pollution in urban areas, and have resulted in significant air quality improvements. It has however been demonstrated that a small amount of platinum group elements, the main active components in catalysts, are emitted during vehicle operation (Konig et al., 1992; Palacios et al., 2000; Moldovan et al., 2002) resulting in elevated concentrations of these normally rare metals in the urban and roadside environment (Gomez et al., 2002). While these metals were believed to remain in the urban and roadside environment, recent studies have suggested the possibility for regional and global dispersion of these elements.

A 2-year project with the co-authors as partners and funded by the Alliance for Global Sustainability was initiated in 2002 to provide a further understanding of PGE transport from roadside environments. This paper presents literature and project-related information on potential regional and long range transport, from automobile catalysts to global distribution.

The distribution and behaviour of anthropogenic platinum-group elements (PGE) in river systems has as yet attracted little attention. Aquiring good quality data in PGE analysis poses a serious challenge to the environmental chemist, not in the least due to the low concentrations at which the PGE are currently found in the environment. Using the River Stour in Kent, U.K. as a case study, the work presented in this paper focuses specifically on the spatial and temporal variability of PGE in fluvial sediments. The analysis of river bed sediments shows high variability both on a catchment scale and on a local scale within sample sites. Moreover, high relative standard deviation points to a heterogeneous distribution of PGE within sediment samples, which is characteristic of the elements and is commonly known as the nugget effect. If unassessed, analytical data are unlikely to be truly representative and the interpretation of PGE data could be inherently flawed. For this reason this paper suggests a need to include thorough quantification and reporting of this variability as a matter of practice in the acquisition of environmental PGE data.

A combined analytical procedure is presented for the quantification of experimentally induced Pt and Pd DNA adducts in living cells by combining a DNA extraction technique with double focusing magnet sector field ICP-MS instrumentation. The proposed method is discussed in terms of possible spectral interferences, instrumental repeatability and experimental reproducibility. The statistical evaluation of a large dataset indicates that the method can be successfully used in experimental studies for the quantification of Pt and Pd DNA adducts.

Automobile exhaust catalysts were introduced in the US in the mid-1970s to reduce traffic-derived air pollution in urban areas, and have resulted in significant air quality improvements. It has however been demonstrated that a small amount of platinum group elements, the main active components in catalysts, are emitted during vehicle operation (Konig et al., 1992; Palacios et al., 2000; Moldovan et al., 2002) resulting in elevated concentrations of these normally rare metals in the urban and roadside environment (Gomez et al., 2002). While these metals were believed to remain in the urban and roadside environment, recent studies have suggested the possibility for regional and global dispersion of these elements.

A 2-year project with the co-authors as partners and funded by the Alliance for Global Sustainability was initiated in 2002 to provide a further understanding of PGE transport from roadside environments. This paper presents literature and project-related information on potential regional and long range transport, from automobile catalysts to global distribution.

Automobile exhaust catalysts were introduced in the US in the mid-1970s to reduce traffic-derived air pollution in urban areas, and have resulted in significant air quality improvements. It has however been demonstrated that a small amount of platinum group elements, the main active components in catalysts, are emitted during vehicle operation (Konig et al., 1992; Palacios et al., 2000; Moldovan et al., 2002) resulting in elevated concentrations of these normally rare metals in the urban and roadside environment (Gomez et al., 2002). While these metals were believed to remain in the urban and roadside environment, recent studies have suggested the possibility for regional and global dispersion of these elements.

A 2-year project with the co-authors as partners and funded by the Alliance for Global Sustainability was initiated in 2002 to provide a further understanding of PGE transport from roadside environments. This paper presents literature and project-related information on potential regional and long range transport, from automobile catalysts to global distribution.