The principal research interests of our group fall into the three interrelated research areas of environmental, analytical and water sciences. We work in the area of water quality and novel technologies used to decrease contamination of water. Our recent interests focus on water fingerprinting to inform the state of the environment and public health.
Emerging micropollutants in the environment
Emerging environmental contaminants including pharmaceuticals, illicit drugs, personal care products and endocrine disruptors are a group of compounds without well understood occurrence, fate and effects in the environment and human health but with the potential to cause such effects. Our research concentrates on identifying new micropollutants in environmental matrices, understanding their fate in the environment and identifying their possible effects on humans and the environment. This includes the development of new analytical methodology primarily utilising liquid chromatography coupled with mass spectrometry to identify and quantify micropollutants and their transformation products at low ppt levels.
The enantiomers of chiral compounds can differ in interactions with chiral environments such as enzymes in the body. Therefore in biological systems they can be recognised as two different substances that elicit different responses: one enantiomer of the same drug may produce the desired therapeutic activity, while the other may be inactive or even toxic. The ratio of active/inactive enantiomer of the chiral drug can change significantly after its administration, metabolism in and excretion from the body. It can be subsequently altered during biological wastewater treatment and when the drug is already present in the environment. Biological processes can lead to stereoselective enrichment or depletion of enantiomeric composition of chiral drugs. Therefore the very same drug might reveal different activity and toxicity and this will depend on its origin and exposure to several factors governing its fate in the environment.
Existing reports on the presence and fate of pharmacologically active compounds, due to their non-enantioselective analysis, do not tackle the problem of their chirality. As a result, current understanding of environmental fate and effects of chiral drugs is limited, might be inaccurate and misleading, as it incorrectly assumes that enantiomers have identical environmental behaviour and toxicity. Therefore to understand and predict the mechanisms governing the fate of chiral drugs, their possible toxicity and impact on the environment, determination of enantiomeric composition of chiral drugs in environmental matrices is essential and constitutes a vital part of our research. This involves also the development of analytical methods capable of enantiomeric separation of chiral drugs and their application in environmental context.
Catalytic ozonation in water treatment
Ozone, due to its high oxidation and disinfection potential, has received much attention in water treatment technology. It is applied in order to improve taste and colour as well as to remove the organic and inorganic compounds in water. Despite the several advantages of using ozone, it has a few disadvantages which limit its application. The main ones are: relatively low solubility and stability in water. Because of both the high cost of ozone production and only partial oxidation of organic compounds present in water, the application of ozonation might not be feasible from an economic point of view. Advanced oxidation processes such as O3/H2O2, UV/O3, UV/H2O2, TiO2/UV, Fenton’s reagents and catalytic ozonation involve the generation of hydroxyl radicals, which are active oxidative species. However, their reactions are not selective and therefore more likely to be hindered by competitive reactions. For that reason, it is also desirable to investigate new methods based on molecular ozone reactions, which allow for both better ozone dissolution and stability in water due to the presence of non-polar materials such as: non-polar fluorinated hydrocarbon solvent or perfluorinated alumina. We are currently investigating the application of metal oxides and zeolites as heterogeneous catalysts for the ozonation of common water micropollutants.
We develop methods utilising primarily chromatographic techniques and mass spectrometry aiming at environmental and forensic applications. We are also interested in new approaches to sample preparation.