Impact of automobile emissions on the levels of platinum and lead in Accra,Ghana

Examination of car fleet records in Accra demonstrates an increasing proportion of catalytic converter-equipped cars in the relatively old car fleet (average age 13 years) due to their import from developed countries. However, only leaded petrol is sold in Ghana. Lead anti-knocking additives, which are known to affect catalyst activity and promote thermal sintering and mechanical abrasion, may increase Pt emissions. This possible synergism prompted the concomitant determination of Pb and Pt levels in road dust and roadside soils in Ghana. Both metals followed traffic density with higher concentrations in urban areas compared to remote sites. In urban areas, the range for Pb (365 +/- 93 microg g(-1) for dust and 291 +/- 76 microg g(-1) for soil) reflects precatalyst levels in Europe and the US, while the range for Pt (39 +/- 24 ng g(-1) for dust and 15 +/- 5.3 ng g(-1) for soil) is typical for the same countries. The elevated Pt concentrations were unexpected due to recent introduction of catalysts to Ghana compared to the prolonged use of catalysts in Europe and the US.     

Element associations in ash from waste combustion in fluidized bed

The incineration of MSW in fluidized beds is a commonly applied waste management practice. The composition of the ashes produced in a fluidized bed boiler has important environmental implications as potentially toxic trace elements may be associated with ash particles and it is therefore essential to determine the mechanisms controlling the association of trace elements to ash particles, including the role of major element composition. The research presented here uses micro-analytical techniques to study the distribution of major and trace elements and determine the importance of affinity-based binding mechanisms in separate cyclone ash particles from MSW combustion. Particle size and the occurrence of Ca and Fe were found to be important factors for the binding of trace elements to ash particles, but the binding largely depends on random associations based on the presence of a particle when trace elements condensate in the flue gas.     

Uranium in stream and mineral water of the Federal Republic of Germany

The concentration of uranium was determined in 944 samples from stream water by the inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) method and represented on a color-shaded contour map. Uranium concentrations in surface water were determined to be between 0.007 μg/l and 43.7 μg/l with median of 0.33 μg/l. The regional distribution of uranium is influenced primarily by lithological and anthropogenic factors. In Mecklenburg, northern Brandenburg, and eastern Schleswig-Holstein, elevated uranium concentrations coincide with the extent of the last Weichselian ice sheet. The maximum concentrations are observed in the surface waters of the old mining districts in the western part of the Ore Mountains and in eastern Thuringia. Elevated concentrations are found in areas of agriculturally used loess soils. These concentrations correlate with the use of phosphate fertilizers. There is a zone of elevated concentrations up to 10.0 μg U/l in the Keuper Sandstone area south of the Thuringian Forest and from northwest of Stuttgart as far as Coburg. The distribution of elevated values in mineral water shows a clear correlation with the elevated values in surface water and the geology of those locations. Bunter and Keuper strata are the most important uranium source.     

Performance of an in situ passive sampling system for metals in stormwater

A passive sampler has been developed and is demonstrated in situ for urban runoff. The passive sampler is compared to conventional composite (time-dependent and flow-weighted) bottle sampling during and between storm events. The sampling was carried out at established stormwater stations; before and after a stormwater detention pond. In situ deployment of the passive sampler provides the metal concentrations, corresponding to the electrochemically available fraction of total metal, for time-dependent samples collected in parallel. The sampler provides improved accuracy compared to bottle sampling because contamination during sample transport and handling is minimised. Laboratory handling is reduced by direct analysis of the accumulated metals on the receiving membrane by laser ablation inductively coupled plasma mass spectrometry. Passive sampling also solves the problem of metal speciation change during transport to the laboratory, which is a potential problem for bottle samples. The low cost and convenience of the passive sampler and subsequent analysis should allow significantly more extensive spatial and temporal monitoring of metals in the aquatic environment than has previously been possible.     

The European Water Framework Directive: Water Quality Classification and Implications to Engineering Planning

The European Water framework directive (WFD) is probably the most important environmental management directive that has been enacted over the last decade in the European Union. The directive aims at achieving an overall good ecological status in all European water bodies. In this article, we discuss the implementation steps of the WFD and their implications for environmental engineering practice while focusing on rivers as the main receiving waters. Arising challenges for engineers and scientists are seen in the quantitative assessment of water quality, where standardized systems are needed to estimate the biological status. This is equally of concern in engineering planning, where the prediction of ecological impacts is required. Studies dealing with both classification and prediction of the ecological water quality are reviewed. Further, the combined emission–water quality approach is discussed. Common understanding of this combined approach is to apply the most stringent of either water quality or emission standard to a certain case. In contrast, for example, the Austrian water act enables the application of only the water quality based approach - at least on a temporary basis.     

Metal capital sustaining a North American city: Iron and copper in New Haven, CT

A detailed inventory shows that an average resident of the City of New Haven depends on a per capita capital stock of 9200 kg/c of iron and 144 kg/c of copper in the city infrastructure, buildings, transportation systems, and equipment. Of the iron stock 28% is in items such as rail cars and ships in ocean trade not permanently within the city, and 22% is devoted to receiving and delivering oil fuel to the city and its surrounding communities. Copper is principally used in the distribution of electric power and in water piping within buildings. The city's 9200 kg/c of iron stock-in-use is less than the 13,000 kg/c national average due to New Haven's lack of heavy industry and relatively small number of large buildings. The 144 kg/c of copper stock-in-use is only 58% of the overall value for the United States, but is comparable to that in cities such as Stockholm, Sweden. Attainment of a level of iron and copper services with contemporary technology in less developed countries to the level enjoyed in New Haven would require consumption of the presently identified world copper resources.     

ANOMALOUS NATURAL SULFATE IN WATER WELLS OF THE GREENBRIER GROUP,WEST VIRGINIA1

ABSTRACT: Many water wells developed in the Middle Mississippian Greenbrier Group of central Greenbrier County, West Virginia, are very productive because of the abundant solution conduits in this karst aquifer. Water from these wells, all of which (with one exception) are clustered in a small area about eight kilometers northwest of Lewisburg, West Virginia, is typically very hard (calcium-magnesium-bicarbonate type). Of 74 wells sampled, eight showed sulfate concentrations ranging from 600 to 1700 mg/l. These wells also showed a much higher than average concentration of calcium, magnesium, chloride, sodium, and, in a few cases, iron. The water from several of these wells was not potable. Previously unpublished work has suggested that dolomite and gypsum dissolution have contributed magnesium and sulfate ions to the ground water. It is also likely that, where sodium, chloride, and iron concentrations are above background, halite dissolution and pyrite oxidation are contributing to the problem. All of these minerals are often associated with the basal waterbearing strata of the Greenbrier Group. In addition, it is possible that the wells are receiving deeply circulating ground waters, via fracture zones, which feed many other well-known sulfur and/or thermal springs in the central Appalachians.     

Source characterisation of atmospheric platinum group element deposition into an ombrotrophic peat bog

Platinum, palladium, rhodium, iridium and osmium were found to be enriched relative to their expected natural concentrations in peat samples from Thoreau's Bog, an ombrotrophic peat bog in Concord, Massachusetts. The source of osmium into the bog was determined from its isotopic composition (187Os/188Os). Osmium is composed of 4% lithogenic osmium from atmospheric soil dust, 41% of anthropogenic osmium and 55% of osmium from a non-lithogenic, non anthropogenic source, with rain being a likely candidate for the latter. Significant anthropogenic and rain contributions are also expected for iridium. In contrast, platinum, palladium and rhodium are almost exclusively anthropogenic. The larger enrichments of platinum, palladium and rhodium indicate that automobile catalysts are the source of platinum group elements to Thoreau's bog. The bog is located approximately 300 m from a major road and, therefore, the occurrence of platinum elements is evidence for regional dispersion of these metals. The absence of a clear trend following the introduction of catalysts indicates that platinum group elements are not quantitatively conserved in peat with downward leaching and plants playing an important role in the accumulation of platinum group elements.