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Bentley, Australia

Stock W.D.,Edith Cowan University | Finn H.,Murdoch University | Parker J.,Western Australia | Dods K.,ChemCentre
PLoS ONE | Year: 2013

Pine plantations near Perth, Western Australia have provided an important food source for endangered Carnaby's Cockatoos (Calyptorhynchus latirostris) since the 1940s. Plans to harvest these plantations without re-planting will remove this food source by 2031 or earlier. To assess the impact of pine removal, we studied the ecological association between Carnaby's Cockatoos and pine using behavioural, nutritional, and phenological data. Pine plantations provided high densities of seed (158 025 seeds ha-1) over a large area (c. 15 000 ha). Carnaby's Cockatoos fed throughout these plantations and removed almost the entire annual crop of pine cones. Peak cockatoo abundance coincided with pine seed maturation. Pine seed had energy and protein contents equivalent to native food sources and, critically, is available in summer when breeding pairs have young offspring to feed. This strong and enduring ecological association clearly suggests that removing pine will have a significant impact on this endangered species unless restoration strategies, to establish alternative food sources, are implemented. © 2013 Stock et al.

Callan A.C.,Edith Cowan University | Hinwood A.L.,Edith Cowan University | Ramalingam M.,Edith Cowan University | Boyce M.,Edith Cowan University | And 3 more authors.
Environmental Research | Year: 2013

A variety of metals are important for biological function but have also been shown to impact health at elevated concentrations, whereas others have no known biological function. Pregnant women are a vulnerable population and measures to reduce exposure in this group are important. We undertook a study of maternal exposure to the metals, aluminium, arsenic, copper, cobalt, chromium, lithium, manganese, nickel, selenium, tin, uranium and zinc in 173 participants across Western Australia. Each participant provided a whole blood and urine sample, as well as drinking water, residential soil and dust samples and completed a questionnaire. In general the concentrations of metals in all samples were low with the notable exception of uranium (blood U mean 0.07 μg/L, range <0.01-0.25 μg/L; urinary U mean 0.018 μg/g creatinine, range <0.01-0.199 μg/g creatinine). Factors that influenced biological concentrations were consumption of fish which increased urinary arsenic concentrations, hobbies (including mechanics and welding) which increased blood manganese concentrations and iron/folic acid supplement use which was associated with decreased concentrations of aluminium and nickel in urine and manganese in blood. Environmental concentrations of aluminium, copper and lithium were found to influence biological concentrations, but this was not the case for other environmental metals concentrations. Further work is underway to explore the influence of diet on biological metals concentrations in more detail. The high concentrations of uranium require further investigation. © 2013 Elsevier Inc.

Patterson B.M.,CSIRO | Patterson B.M.,University of New South Wales | Shackleton M.,CSIRO | Furness A.J.,CSIRO | And 7 more authors.
Water Research | Year: 2010

Water quality changes associated with the passage of aerobic reverse osmosis (RO) treated recycled water through a deep anaerobic pyritic aquifer system was evaluated in sediment-filled laboratory columns as part of a managed aquifer recharge (MAR) strategy. The fate of nine recycled water trace organic compounds along with potential negative water quality changes such as the release of metal(loid)s were investigated in large-scale columns over a period of 12 months. The anaerobic geochemical conditions provided a suitable environment for denitrification, and rapid (half-life <1-25 days) degradation of the endocrine disrupting compounds (bisphenol A, 17β-estradiol, 17α-ethynylestradiol), and iodipamide. However, pharmaceuticals (carbamazepine and oxazepam), disinfection by-products (N-nitrosodimethylamine, N-nitrosomorpholine) and iohexol did not degrade rapidly (half-life > 100 days). High retardation coefficients (R) determined for many of the trace organics (R 13 to 67) would increase aquifer residence time and be beneficial for many of the slow degrading compounds. However, for the trace organics with low R values (1.1-2.6) and slow degradation rates (half-life > 100 days), such as N-nitrosodimethylamine, N-nitrosomorpholine and iohexol, substantial biodegradation during aquifer passage may not occur and additional investigations are required. Only minor transient increases in some metal(loid) concentrations were observed, as a result of either pyrite oxidation, mineral dissolution or pH induced metal desorption, followed by metal re-sorption downgradient in the oxygen depleted zone. Crown Copyright © 2009.

Hinwood A.L.,Edith Cowan University | Callan A.C.,Edith Cowan University | Ramalingam M.,Edith Cowan University | Boyce M.,Edith Cowan University | And 3 more authors.
Environmental Research | Year: 2013

Recent literature suggests that exposure to low concentrations of heavy metals may affect both maternal and child health. This study aimed to determine the biological heavy metals concentrations of pregnant women as well as environmental and dietary factors that may influence exposure concentrations. One hundred and seventy three pregnant women were recruited from Western Australia, each providing a sample of blood, first morning void urine, residential soil, dust and drinking water samples. Participants also completed a questionnaire which included a food frequency component. All biological and environmental samples were analysed for heavy metals using ICP-MS. Biological and environmental concentrations of lead and mercury were generally low (Median Pb Drinking Water (DW) 0.04 μg/L; Pb soil <3.0 μg/g; Pb dust 16.5 μg/g; Pb blood 3.67 μg/L; Pb urine 0.55; μg/L Hg DW <0.03; Hg soil <1.0 μg/g; Hg dust <1.0 μg/g; Hg blood 0.46 μg/L; Hg urine <0.40 μg/L). Cadmium concentrations were low in environmental samples (Median CdDW 0.02 μg/L; Cdsoil <0.30. ug/g; Cddust <0.30) but elevated in urine samples (Median 0.55 μg/L, creatinine corrected 0.70 μg/g (range <0.2-7.06 μg/g creatinine) compared with other studies of pregnant women. Predictors of increased biological metals concentrations in regression models for blood cadmium were residing in the Great Southern region of Western Australia and not using iron/folic acid supplements and for urinary cadmium was having lower household annual income. However, these factors explained little of the variation in respective biological metals concentrations. The importance of establishing factors that influence low human exposure concentrations is becoming critical in efforts to reduce exposures and hence the potential for adverse health effects. © 2013.

Basavaraj S.,Curtin University Australia | Benson H.A.E.,Curtin University Australia | Cruickshank C.,ChemCentre | Brown D.H.,Curtin University Australia | Chen Y.,Curtin University Australia
Rapid Communications in Mass Spectrometry | Year: 2011

A simple and reliable liquid chromatography/mass spectrometry (LC/MS) method to monitor pegylation of resveratrol is described. The developed LC/MS method can separate and quantify unmodified MeO-PEG-OH, carboxylic acid terminated PEG, resveratrol and PEG-resveratrol prodrugs. This methodology was able to monitor and determine the extent of conversion of MeO-PEG-OH into respective acidic functional derivatives such as MeO-PEG succinylester acid (MeO-PEGO-SuccOH), which was found to be complete. The developed method was also utilised to determine the extent of conjugation of resveratrol to carboxylic acid terminated PEG. The conversion of carboxylic acid terminated PEG into a PEG-resveratrol conjugate was found to be 100% and 73%, respectively, for MeO-PEG succinylamide resveratrol (MeO-PEGN-Succ-RSV) and MeO-PEG succinylester resveratrol (MeO-PEGO-Succ-RSV). The 100% conjugation of MeO-PEGN-Succ-RSV is consistent with the result obtained from a nuclear magnetic resonance (NMR) study. The average molecular weights determined by LC/MS for MeO-PEG-OH, MeO-PEGO-SuccOH and MeO-PEGO-Succ-RSV were found to be 2108, 2321 and 2423 Da, respectively. These data correlate well with the theoretical values. This methodology proved to be simple and effective in determining the extent of functionalisation of PEG and its conjugation to resveratrol. Overall our LC/MS method coupled with NMR permitted complete characterisation of the polymeric prodrug pegylated-resveratrol and the reaction precursors. © 2011 John Wiley & Sons, Ltd.

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