Description:
Pattern recognition methods such as linear discriminant analysis and principal component analysis are useful tools for the identification of analytes such as metal ions. These typically use a number of distinct molecular probes that exhibit cross-reactivity. Here we report a single molecule that demonstrates varying response in different solvents, therefore enabling the combination of probe and solvent to generate the required array diversity. Seven toxic metal ions were introduced as aqueous samples, and PCA and LDA techniques applied. The array could correctly identify all metals in pure water samples, all metals in doped lake-water samples. Further, we have explored the limit of detection of the system for two metal ions, Cu(ii) and Hg(ii), confirming the promise of the system as a candidate to identify toxic metals in environmental water sources.
Description:
Pattern recognition methods such as linear discriminant analysis and principal component analysis are useful tools for the identification of analytes such as metal ions. These typically use a number of distinct molecular probes that exhibit cross-reactivity. Here we report a single molecule that demonstrates varying response in different solvents, therefore enabling the combination of probe and solvent to generate the required array diversity. Seven toxic metal ions were introduced as aqueous samples, and PCA and LDA techniques applied. The array could correctly identify all metals in pure water samples, all metals in doped lake-water samples. Further, we have explored the limit of detection of the system for two metal ions, Cu(ii) and Hg(ii), confirming the promise of the system as a candidate to identify toxic metals in environmental water sources.
Description:
Iron-sulfide minerals in benthic sediments may sequester potentially toxic trace elements that are introduced to estuaries from natural and anthropogenic sources (Chapman et al., 1998, Morse and Luther, 1999, Simpson et al., 2002 and Teasdale et al., 2003). Understanding iron-sulfide formation in benthic sediments is therefore central to assessing the risk posed by sedimentary trace elements (Machado et al., 2004, Burton et al., 2005a and Burton et al., 2006a). This report provides a baseline description of sedimentary iron-sulfide and trace element behaviour in Coombabah Lake – a sub-tropical estuarine lake in southern Moreton Bay, Australia (Fig. 1).
Description:
"Three sampling campaigns were conducted in the Ballarat, Creswick and Maldon areas. The sampling area is part of the Golden Triangle region where significant gold-mining activities took place from the 1850s to the present day. [...] Locations were chosen to evaluate arsenic distribution in soils, surface waters and plants in different environments. Easy access to sampling locations allowed detailed scientific sampling, especially in the seasonality study. The different range of environments such as agricultural, state forest, mining, urban and rural provided an opportunity to compare the concentrations of arsenic and other elements in the study area. The study of the three selected areas combined provided further understanding of possible exposure and pathways through which arsenic can get into the food chain. "The objective of the study is to measure levels of heavy metals/metalloids in soils, water and plants in various environments, identify whether the heavy metals/metalloids are mobile and bioavailable and understand the importance of clays and oxide complexes in the fixation of metals."
Description:
"Three sampling campaigns were conducted in the Ballarat, Creswick and Maldon areas. The sampling area is part of the Golden Triangle region where significant gold-mining activities took place from the 1850s to the present day. [...] Locations were chosen to evaluate arsenic distribution in soils, surface waters and plants in different environments. Easy access to sampling locations allowed detailed scientific sampling, especially in the seasonality study. The different range of environments such as agricultural, state forest, mining, urban and rural provided an opportunity to compare the concentrations of arsenic and other elements in the study area. The study of the three selected areas combined provided further understanding of possible exposure and pathways through which arsenic can get into the food chain. "The objective of the study is to measure levels of heavy metals/metalloids in soils, water and plants in various environments, identify whether the heavy metals/metalloids are mobile and bioavailable and understand the importance of clays and oxide complexes in the fixation of metals."