The challenge
Detecting trace contaminant concentrations
Many contaminants occur in the environment at concentrations in the sub-parts per billion (microgram per litre) range. Detecting such baseline concentrations and the effects of added contamination is beyond the capability of most routine analytical laboratories.
This requires particular skills both in sampling and in trace and ultratrace analysis, to avoid both contamination and losses during sample collection and handling.
Measuring the chemical forms of the contaminants (speciation), which allows us to better understand bioavailability and toxicity, is an added challenge.
Our response
Developing methods for ultratrace analysis and speciation of contaminants
We have developed methods for trace analysis of contaminants (both inorganic, e.g. metals, and organic contaminants including contaminants of emerging concern), determination of speciation analyses (e.g. HPLC-ICP-MS, LC-MM-MS, ion selective electrodes, and computer-based chemical speciation models) and measures of lability and (bio)availability (e.g. DGT, Donnan dialysis, and lability resins).
Ultratrace analysis and speciation metals in waters
With a dedicated clean room and state-of-the-art analytical instrumentation, we have pioneered methods that have enabled the detection of baseline concentrations of metals such as Cu, Pb, Cd, Zn, Ni, Al, As, Se and Hg in coastal seawater (typically at parts per trillion (ng/L) concentrations).
We pioneered a lot of the early research on metal speciation, however, much was beyond the scope of routine laboratories. In response, we developed a robust method that involved the rapid separation of labile (potentially bioavailable) metal forms on a column packed with a chelating resin (Chelex). This has enabled speciation analysis by commercial laboratories.
Methods for the determination of metal complexing capacity have enabled determination of the extent to which dissolved organic matter in waters is able to bind metals such as copper and reduce their bioavailability.
In the case of mercury, we have developed ultratrace methods for methylmercury to discriminate it from inorganic and metallic mercury in waters, and also in sediments and biota.
Contaminants in other environmental matrices
Our environmental skills extend to sediment, soils and biota where the concentrations are higher, but nevertheless requiring specialist analytical capabilities. This includes a wide range of traditional (e.g. metals and organics) and emerging (e.g. per- and poly-fluroalkyl substances, endocrine disrupting chemicals, pharmaceuticals and personal care products, and nanoparticles) contaminants that are released to the environment through human activities such as agriculture, industrial developments, mining, and urbanisation.
Our laboratories have provided reliable analytical data to industry and government in these and related activities over many years.
The mining industry is a major source of metal contaminants and we have had an ongoing involvement with the extractive mineral industries in Papua New Guinea, Indonesia and Australia over many years, determining metal speciation and bioavailability in both surface waters and deep-sea locations. We regularly conduct ultratrace analysis and trace metal speciation studies for a wide range of clients both locally and internationally.
The results
Providing assessment solutions for industry and government
The mining industry is a major source of metal contaminants and we have had an ongoing involvement with the extractive mineral industries in Papua New Guinea, Indonesia and Australia over many years, determining metal speciation and bioavailability in both surface waters and deep-sea locations.
Metal contamination arises from many other urban and industrial activities including power stations, water utilities, coal mining, urban runoff, dredged sediment disposal and our capability has provided reliable analytical data to industry and government in these and related areas over many years.