Antimicrobial resistance is a global health issue. The discharge, maintenance and transfer of antimicrobial resistance to the aquatic environment and the risk this presents is relatively unknown. This work describes the presence and distribution of antimicrobial resistant Escherichia coli in surface waters of seven rivers in south east Queensland, Australia.

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The presence of 28 antibiotics in three hospital effluents, five wastewater treatment plants (WWTPs), six rivers and a drinking water storage catchment were investigated within watersheds of South-East Queensland, Australia. All antibiotics were detected at least once, with the exception of the polypeptide bacitracin which was not detected at all. Antibiotics were found in hospital effluent ranging from 0.01-14.5 [mu]g L(-1), dominated by the beta-lactam, quinolone and sulphonamide groups.

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DEET (N,N-diethyl-m-toluamide) is the active ingredient of most commercial insect repellents. This compound has commonly been detected in aquatic water samples from around the world indicating that DEET is both mobile and persistent, despite earlier assumptions that DEET was unlikely to enter aquatic ecosystems. DEET's registration category does not require an ecological risk assessment, thus information on the ecological toxicity of DEET is sparse.

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We validated a novel method for screening Escherichia coli resistance to antibiotics in environmental samples using modified Difco MI agar (Becton Dickinson) impregnated with selected antibiotics (tetracycline, ampicillin, cephalexin, and sulfamethoxazole), termed MI-R. This method combines an existing rapid assessment technique for E.

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A number of marine microalgae are known to produce toxins that can accumulate in shellfish and when eaten, lead to toxic and potentially fatal reactions in humans. This paper reports on the occurrence and seasonal variations of algal toxins in the waters, phytoplankton and shellfish of Southeast Queensland, Australia.

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Removal of 28 human and veterinary antibiotics was assessed in a conventional (activated sludge) and advanced (microfiltration/reverse osmosis) wastewater treatment plant (VJVvrTP) in Brisbane, Australia. The dominant antibiotics detected in wastewater influents were cephalexin (med. 4.6 gL(,)(-1) freq. 100%), ciprofloxacin (med. 3.8 [mu]gL(-1) freq. 100%), cefaclor (med. 0.5 [mu]gL(-1), freq. 100%), sulphamethoxazole (med. 0.36 [mu]gL(-1), freq. 100%) and trimethoprim (med.

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Awareness of antibiotics in wastewaters and aquatic ecosystems is growing as investigations into alternate pollutants increase and analytical techniques for detecting these chemicals improve. The presence of three antibiotics (ciproffoxacin, norfloxacin and cephalexin) was evaluated in both sewage effluent and environmental waters downstream from a sewage discharge.

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Tissue samples of liver and blubber were salvaged from fifty-three dugong (Dugong dugon) carcasses stranded along the Queensland coast between 1996 and 2000. Liver tissue was analysed for a range of heavy metals and blubber samples were analysed for organochlorine compounds. Metal concentrations were similar in male and female animals and were generally highest in mature animals.

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With increasing human pressures on coastal ecosystems, there is a need to develop better approaches to assess and monitor anthropogenic influences in these systems. The aims of this thesis were to a) develop indicators that describe and predict nutrient input effects, b) synthesise and interpret these indicators in assessment programs, and c) provide cost-effective methods for use in regular monitoring programs.

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Current shrimp pond management practices generally result in elevated concentrations of nutrients, suspended solids, bacteria and phytoplankton compared with the influent water. Concerns about adverse environmental impacts caused by discharging pond effluent directly into adjacent waterways have prompted the search for cost-effective methods of effluent treatment.

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