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Karen Kennedy,
Thomas Schroeder,
Melanie Shaw,
David Haynes,
Stephen Lewis,
Christie Bentley,
Chris Paxman,
Steve Carter,
Vittorio E Brando,
Michael Bartkow, Laurence Hearn,
Jochen F Mueller
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ABSTRACT: Photosystem II (PSII) herbicides are used in large quantities on agricultural lands adjoining the Great Barrier Reef (GBR). Routine monitoring at 14 sites in inshore waters of the GBR using passive sampling techniques detected diuron (32-94% of sampling periods) at maximum concentrations of 1.7-430ng L(-1) in the relatively pristine Cape York Region to the Mackay Whitsunday Region, respectively. A PSII herbicide equivalent (PSII-HEq) index developed as an indicator for reporting was dominated by diuron (average contribution 89%) and typically increased during the wet season. The maximum PSII-HEq indicates the potential for photosynthetic inhibition of diatoms, seagrass and coral-symbionts. PSII herbicides were significantly positively correlated with remotely sensed coloured dissolved organic matter, a proxy for freshwater extent. Combining these methods provides for the first time the potential to cost-effectively monitor improvements in water quality entering the GBR with respect to exposure to PSII herbicides.
Marine pollution bulletin 12/2011; 65(4-9):292-305. · 2.63 Impact Factor
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ABSTRACT: In March 2009, a cargo ship spilled 250 tons of heavy fuel oil off the Queensland coast of Australia. The pristine National Park Moreton Island, seven nautical miles to the east of the spill site, was most affected by the oil slick. Contamination of the island's shoreline was widespread, with freshwater wetlands particularly slow to recover as clean-up needed to be carefully managed to avoid damage to this sensitive ecosystem. During the clean-up process on Moreton Island a monitoring program was initiated using traditional chemical analysis in combination with bioanalytical techniques to assess the extent and variability in contamination at sites on the shoreline and freshwater wetlands. Water accommodated fractions (WAF) of oil residues from samples taken directly after the spill on the shoreline showed the same level of toxic potency as samples from the wetland while baseline-toxicity equivalent concentrations (baseline-TEQ) and 2,3,7,8-tetrachlorodibenzodioxin equivalent concentrations (TCDDEQ) were much lower in oil collected from the sandy beach. The umuC assay for genotoxicity and the E-SCREEN assay for estrogenic effects indicated the extracts were not genotoxic or estrogenic. PAH concentrations and toxicity in grab water samples were below detectable levels, however, extracts from time integrated silicone passive samplers deployed for several weeks at the contaminated sites gave measurable responses in the bioassays with TCDDEQ levels increased relative to the control site. The low levels of baseline-TEQ and TCDDEQ present after 8 months had further decreased 6 months later indicating satisfactory recovery of this pristine ecosystem after an oil spill.
Journal of Environmental Monitoring 01/2011; 13(3):713-20. · 1.99 Impact Factor
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ABSTRACT: N-nitrosodimethylamine (NDMA) can be formed when secondary effluents are disinfected by chloramines. By means of bench scale experiments this paper investigates operational parameters than can help Advanced Water Treatment Plants (AWTPs) to reduce the formation of NDMA during the production of high quality recycled water. The formation of NDMA was monitored during a contact time of 24h using dimethylamine as NDMA model precursor and secondary effluent from wastewater treatment plants. The three chloramine disinfection strategies tested were pre-formed and in-line formed monochloramine, and pre-formed dichloramine. Although the latter is not employed on purpose in full-scale applications, it has been suggested as the main contributing chemical generating NDMA during chloramination. After 24h, the NDMA formation decreased in both matrices tested in the order: pre-formed dichloramine>in-line formed monochloramine≫pre-formed monochloramine. The most important parameter to consider for the inhibition of NDMA formation was the length of contact time between disinfectant and wastewater. Formation of NDMA was initially inhibited for up to 6h with concentrations consistently <10 ng/L during these early stages of disinfection, regardless of the disinfection strategy. The reduction of the contact time was implemented in Bundamba AWTP (Queensland, Australia), where NDMA concentrations were reduced by a factor of 20 by optimizing the disinfection strategy.
Journal of hazardous materials 01/2011; 185(2-3):1575-81. · 4.14 Impact Factor
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ABSTRACT: Human polybrominated diphenyl ether (PBDE) exposure occurs through a range of pathways including: ingestion of dust including
hand-to-mouth contact; inhalation (air/particulate matter); and ingestion via food including the unique nutrition sources
of human milk and placental transfer. While inhalation has been deemed a minor source of exposure, ingestion of food and dust
make greater contributions to overall PBDE body burden with intake via dust reported to be much higher in infants than in
adults.
PBDEs have been detected in samples of human milk, blood serum, cord blood, and adipose tissue worldwide. Concentrations have
been found to be highest in populations from North America, followed by Australia, Europe, and Asia. While factors such as
gender and parity may not affect concentrations, occupational exposure and age (infants and children) are associated with
higher PBDE concentrations. In contrast to “traditional” persistent organic pollutants, there is an inverse relationship between
PBDE body burden and age. Predicted body burden calculated using available information on intake and elimination rates of
BFRs appears to underestimate measured human body burden data obtained through analysis of BFRs in blood or human milk. This
may be due to unknown exposure or inaccurate elimination data. Further exposure studies should focus on younger age groups
and an investigation of human PBDE half-lives.
KeywordsAdipose tissue-Blood-Body burden-Exposure-Half-lives-Human milk
11/2010: pages 203-239;
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ABSTRACT: Silicone rubber passive samplers spiked with 4 deuterated performance reference compounds were deployed for 29-33 days to estimate the concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in 9 streams in Victoria, Australia, following a wildfire. Silicone rubber strips of 2 thicknesses were used to obtain information on the status of uptake of the chemicals of interest at retrieval. In addition, we monitored the stream macroinvertebrate community for potential effects of PAHs or other fire organics. All selected PAHs were detected in the passive samplers and the sampling rates ranged from 0.5 to 50 L/day significantly varying between sites but not compounds, presumably due to differences in current velocity. The estimated water concentrations were 0.1-10 ng/L for total PAHs with phenanthrene, pyrene and fluoranthene accounting for 91% of the total concentration. All PAHs were a factor of 1000 or more below the reported 48-h median lethal concentrations (48-h LC50) for Daphnia magna. Two sites located closest to the fires exhibited elevated concentrations compared to the other sites and the passive samplers in these sites remained in the integrative uptake regime for all compounds, suggesting precipitation-associated PAH input. No acute toxic effects of PAHs or other fire organics on the invertebrate community were detected using a biotic index for organic toxicants (SPEAR), whereas a non-specific biotic index (SIGNAL) decreased in two sites indicating impacts from changes in other environmental parameters. We conclude (1) that silicone-based passive samplers with two different area-to-volume ratios represent a promising tool for determining organic toxicants and (2) that PAHs from wildfires are unlikely to be a common main cause for fire-related ecological effects in streams adjacent to burnt regions.
Water Research 08/2010; 44(15):4590-600. · 4.86 Impact Factor
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ABSTRACT: Polybrominated diphenyl ethers (PBDEs) are lipophilic, persistent pollutants found worldwide in environmental and human samples. Exposure pathways for PBDEs remain unclear but may include food, air and dust. The aim of this study was to conduct an integrated assessment of PBDE exposure and human body burden using 10 matched samples of human milk, indoor air and dust collected in 2007-2008 in Brisbane, Australia. In addition, temporal analysis was investigated comparing the results of the current study with PBDE concentrations in human milk collected in 2002-2003 from the same region. PBDEs were detected in all matrices and the median concentrations of BDEs -47 and -209 in human milk, air and dust were: 4.2 and 0.3 ng/g lipid; 25 and 7.8 pg/m(3); and 56 and 291 ng/g dust, respectively. Significant correlations were observed between the concentrations of BDE-99 in air and human milk (r=0.661, p=0.038) and BDE-153 in dust and BDE-183 in human milk (r=0.697, p=0.025). These correlations do not suggest causal relationships - there is no hypothesis that can be offered to explain why BDE-153 in dust and BDE-183 in milk are correlated. The fact that so few correlations were found in the data could be a function of the small sample size, or because additional factors, such as sources of exposure not considered or measured in the study, might be important in explaining exposure to PBDEs. There was a slight decrease in PBDE concentrations from 2002-2003 to 2007-2008 but this may be due to sampling and analytical differences. Overall, average PBDE concentrations from these individual samples were similar to results from pooled human milk collected in Brisbane in 2002-2003 indicating that pooling may be an efficient, cost-effective strategy of assessing PBDE concentrations on a population basis. The results of this study were used to estimate an infant's daily PBDE intake via inhalation, dust ingestion and human milk consumption. Differences in PBDE intake of individual congeners from the different matrices were observed. Specifically, as the level of bromination increased, the contribution of PBDE intake decreased via human milk and increased via dust. As the impacts of the ban of the lower brominated (penta- and octa-BDE) products become evident, an increased use of the higher brominated deca-BDE product may result in dust making a greater contribution to infant exposure than it does currently. To better understand human body burden, further research is required into the sources and exposure pathways of PBDEs and metabolic differences influencing an individual's response to exposure. In addition, temporal trend analysis is necessary with continued monitoring of PBDEs in the human population as well as in the suggested exposure matrices of food, dust and air.
Environment international 05/2009; 35(6):864-9. · 4.79 Impact Factor
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[show abstract]
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ABSTRACT: Polybrominated diphenyl ethers (PBDEs) are lipophilic, persistent pollutants found worldwide in environmental and human samples. Exposure pathways for PBDEs remain unclear but may include food, air and dust. The aim of this study was to conduct an integrated assessment of PBDE exposure and human body burden using 10 matched samples of human milk, indoor air and dust collected in 2007–2008 in Brisbane, Australia. In addition, temporal analysis was investigated comparing the results of the current study with PBDE concentrations in human milk collected in 2002–2003 from the same region. PBDEs were detected in all matrices and the median concentrations of BDEs -47 and -209 in human milk, air and dust were: 4.2 and 0.3 ng/g lipid; 25 and 7.8 pg/m3; and 56 and 291 ng/g dust, respectively. Significant correlations were observed between the concentrations of BDE-99 in air and human milk (r = 0.661, p = 0.038) and BDE-153 in dust and BDE-183 in human milk (r = 0.697, p = 0.025). These correlations do not suggest causal relationships — there is no hypothesis that can be offered to explain why BDE-153 in dust and BDE-183 in milk are correlated. The fact that so few correlations were found in the data could be a function of the small sample size, or because additional factors, such as sources of exposure not considered or measured in the study, might be important in explaining exposure to PBDEs. There was a slight decrease in PBDE concentrations from 2002–2003 to 2007–2008 but this may be due to sampling and analytical differences. Overall, average PBDE concentrations from these individual samples were similar to results from pooled human milk collected in Brisbane in 2002–2003 indicating that pooling may be an efficient, cost-effective strategy of assessing PBDE concentrations on a population basis. The results of this study were used to estimate an infant's daily PBDE intake via inhalation, dust ingestion and human milk consumption. Differences in PBDE intake of individual congeners from the different matrices were observed. Specifically, as the level of bromination increased, the contribution of PBDE intake decreased via human milk and increased via dust. As the impacts of the ban of the lower brominated (penta- and octa-BDE) products become evident, an increased use of the higher brominated deca-BDE product may result in dust making a greater contribution to infant exposure than it does currently. To better understand human body burden, further research is required into the sources and exposure pathways of PBDEs and metabolic differences influencing an individual's response to exposure. In addition, temporal trend analysis is necessary with continued monitoring of PBDEs in the human population as well as in the suggested exposure matrices of food, dust and air. Copyright © 2009 Elsevier Ltd All rights reserved.
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