http://pure-oai.bham.ac.uk/ws/files/11961627/Critical_Review_of_Receptor_Modelling4_PostPrint.pdf

Critical review of receptor modelling for particulate matter: A case study of India

Source apportionment of airborne particulates through receptor modeling: Indian scenario

Urban road dust can be highly enriched with trace metals such as copper, lead, zinc, and platinum group elements (PGEs) that are released primarily from vehicles. Concentrations of these metals are up to about 100 times higher than background levels. Lead concentrations in sediment core have declined dramatically due to phase out of leaded gasoline. Recent ban on the use of lead wheel balancing weight in Europe and in some US states will accelerate the decline of lead in the environment. Concentrations of copper, zinc, and PGEs in sediments in many urban areas have increased continuously due to increase of urban sprawl and increased numbers and travel distance of vehicle. Wear of brake pads and tyres are the primary sources of copper and zinc in urban road dust. PGEs have been released from catalytic converters since the mid-1970s. Contaminated urban road dust is picked up by stormwater runoff and delivered into local receiving waterbodies (e.g. streams, rivers, lakes, and estuaries). Concentratio...

Review of pollutants in urban road dust and stormwater runoff: part 1. Heavy metals released from vehicles

Emissions of toxic substances such as oxides of carbon, nitrogen, sulphur, and, in addition, aromatic hydrocarbons, aldehydes and heavy metals are the most serious problem of road traffic affecting landscape. Platinum group elements (PGE), which are the main component of the catalyst, are one of the main sources of heavy metals in the environment. Here, we review the way by which emissions and forms of the emitted PGE end up in the environment especially to the soil-water-plant-animal system. The major points discussed are the following: 1) the main sources of PGE emission are automobile exhaust catalysts; 2) hospitals, where platinum is widely used to treat malignant neoplasm, and urban waste water belonging to other important sources of PGE in the environment; 3) soil is one of the most important components of the environment that may be contaminated with platinum metals; 4) phytotoxicity of PGE depends on the following conditions: the concentration of metals in the soil, time of exposure, the chemical form of metal, the chemical composition of exposed soil and plant species; 5) animals are also endangered by the increasing concentration of PGE in the environment. Moreover, we pay our attention to thiol-based mechanisms of how an organism protects itself against platinum group elements.

/pdf/the-effects-on-soil-water-plant-animal-systems-by-platinum-3fohlemsq1.pdf

The effects on soil/water/plant/animal systems by platinum group elements

Palladium contamination has attracted widespread attention due to the toxicity and the wide use of palladium species. Consequently, development of convenient and effective methods for palladium detection is of great importance. Herein, a new colorimetric and near-infrared (NIR) fluorescent turn-on probe based on the Tsuji-Trost reaction for palladium was developed. This probe can be used to detect palladium in aqueous solution (for example, in pH 7.4 PBS buffer with 0–20% DMSO) under mild conditions with high selectivity and sensitivity, giving rapid (within 2 min) and distinct dual colorimetric and NIR fluorescent turn-on signal changes with a detection limit as low as 2.2 nM. A paper test strip system was prepared with this probe for a convenient visual detection of palladium. In addition, MTT assays showed that this probe has low cytotoxicity and detection of palladium in real drug samples and living cells was successfully applied with this probe, indicating this probe has a good application prospect.

A highly selective and sensitive colorimetric and near-infrared fluorescent turn-on probe for rapid detection of palladium in drugs and living cells

This paper presents the first study of accessing the Pt, Pd and Rh levels in road dusts collected from Hyderabad city, India, as these metals, emitted from automobile catalytic converters, are accumulating in the environment causing concern about human health and ecological risks. Samples were analyzed by ICP-MS following preconcentration by NiS-fire assay and Te coprecipitation. Pt (1.5–43 ng/g), Pd (1.2–58 ng/g) and Rh (0.2–14.2 ng/g) concentrations obtained were above upper crust values, but were lower when compared with several other cities around the world. Dust samples from road junctions and traffic signals with heavy and erratic traffic flow showed higher PGE levels than those from roads with low and free flow traffic suggesting that traffic flow conditions greatly influenced emission of PGE from the catalyst. Significant correlation of Pt, Pd and Rh indicate a common source for these metals. PGE were also positively correlated with Ce, Zr, Hf and Y. These positive inter-element correlations identified traffic as the main source of PGE emission to the roadway environment. The results obtained indicate to an appreciable increase in auto catalyst-derived PGE. In consideration of the adverse effects of PGE, monitoring their level and transformation paths is of prime importance.

Anthropogenic platinum, palladium and rhodium concentrations in road dusts from Hyderabad city, India

A solvent extraction method using diisobutyle ketone (DIBK) is designed for the accurate and precise estimation of very low concentrations of gold in rocks, ores and other geological samples. 30 g sample was digested using aqua regia after roasting and gold content was extracted into DIBK phase consisting of Aliquat™ 336 and estimated by flame atomic absorption spectrometer (F-AAS). Samples having gold concentration <0.1 μg/g were estimated using graphite furnace atomic absorption spectrometer (GF-AAS). Results of DIBK extraction were compared to those obtained by other well established methods, such as classical Pb-fire assay and methyl isobutyl ketone (MIBK)-AAS methods. Comparison was also made with results obtained by the direct determination of gold by inductively coupled plasma mass spectrometry (ICP-MS) technique. The analytical results for international gold reference materials measured by the proposed method were in close agreement with those obtained by other well established methods and recommended values. Detection limits (20 ng/g by F-AAS, 0.1 ng/g by GF-AAS and 0.01 ng/g by ICP-MS) of gold (3 σ × total procedure blank) is very low and could be further improved by using high pure acids and other reagents.

/pdf/a-rapid-method-for-the-determination-of-gold-in-rocks-ores-s6b6oc58gl.pdf

A Rapid Method for the Determination of Gold in Rocks, Ores and Other Geological Materials by F-AAS and GF-AAS After Separation and Preconcentration by DIBK Extraction for Prospecting Studies

S. L. Ramesh

Papers

Anthropogenic platinum, palladium and rhodium concentrations in road dusts from Hyderabad city, India

A Rapid Method for the Determination of Gold in Rocks, Ores and Other Geological Materials by F-AAS and GF-AAS After Separation and Preconcentration by DIBK Extraction for Prospecting Studies