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1.
Chemosphere ; 208: 975-983, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30068041

ABSTRACT

Perfluoroalkyl substances (PFASs) have been used in large quantities for a variety of applications in Australian industry and household products. Through the course of their everyday use, PFASs enter the wastewater stream however current treatment processes provide only partial removal of these chemicals from wastewater. The release of treated effluent and re-use of biosolids represents an important point source of PFASs into the Australian environment yet the scale of PFAS release from Australian WWTPs is unknown. For the first time, influent, effluent and biosolids samples from 14 WWTPs across Australia were assessed for 9 PFASs and the national loads of these PFASs released from WWTPs estimated. Ʃ9PFASs ranged from 0.98 to 440 ng/L (influent), 21-560 ng/L (effluent) and 5.2-150 ng/g (biosolids). National loads of PFOA and PFOS in effluent were estimated at 65 kg and 26 kg per annum respectively. In biosolids, annual loads were estimated at 2 kg and 8 kg respectively. The continued detection of PFOS over a decade after its phase out, the increasing use of PFOS alternatives together with their resistance to degradation processes suggests that PFASs will be a priority for regulators and waste management to prevent further contamination of Australia's water resources.


Subject(s)
Fluorocarbons/analysis , Waste Management/methods , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Australia , Wastewater/analysis
2.
Int J Hyg Environ Health ; 221(7): 1068-1075, 2018 08.
Article in English | MEDLINE | ID: mdl-30037723

ABSTRACT

Women with polycystic ovarian syndrome (PCOS) undergoing treatment for infertility could be a sensitive subpopulation for endocrine effects of exposure to perfluorinated alkyl acids (PFAAs), persistent organic pollutants with potential endocrine activity. Women with, PCOS (n = 30) and age- and BMI-matched controls (n = 29) were recruited from a UK fertility clinic in 2015. Paired serum and follicular fluid samples were collected and analysed for 13 PFAAs. Sex steroid and thyroid hormones, and metabolic markers were measured and assessed for associations with serum PFAAs. Four PFAAs were detected in all serum and follicular fluid samples and concentrations in the two matrices were highly correlated (R2 > 0.95): perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoic acid (PFNA). Serum PFOS was positively associated with age (1 ng/mL per yr, p < 0.05) and was higher in PCOS cases than controls (geometric mean [GM] 3.9 vs. 3.1 ng/mL, p < 0.05) and in women with irregular vs. regular menstrual cycles (GM 3.9 vs. 3.0 ng/mL, p = 0.01). After adjustment for confounders, serum testosterone was significantly associated with PFOA, PFHxS, PFNA, and the molar sum of the four frequently detected serum PFAAs (approximately 50 percent increase per ln-unit) among controls but not PCOS cases. HbA1c in PCOS cases was inversely associated with serum PFOA, PFHxs, and sum of PFAAs (2-3 mmol/mol per ln-unit). In controls, fasting glucose was positively associated with serum PFOA and sum of PFAAs (0.25 nmol/L per ln-unit increase in PFAAs). Few other associations were observed. The analyses and findings here should be considered exploratory in light of the relatively small sample sizes and large number of statistical comparisons conducted. However, the data do not suggest increased sensitivity to potential endocrine effects of PFAAs in PCOS patients.


Subject(s)
Alkanesulfonic Acids/analysis , Environmental Pollutants/analysis , Fatty Acids/analysis , Fluorocarbons/analysis , Follicular Fluid/chemistry , Infertility, Female/metabolism , Polycystic Ovary Syndrome/metabolism , Adult , Female , Gonadal Steroid Hormones/blood , Humans , Prospective Studies , Sex Hormone-Binding Globulin/analysis , Thyroid Hormones/blood , United Kingdom
3.
J Hazard Mater ; 331: 132-141, 2017 Jun 05.
Article in English | MEDLINE | ID: mdl-28254660

ABSTRACT

Leachate from 27 landfills was analysed for nine perfluoroalkyl substances (PFASs). Five PFASs were detected ubiquitously, with perfluorohexanoate (PFHxA) the predominant PFAS (mean 1700ng/L; range 73-25,000ng/L). Despite the complexity of landfill-specific factors, some general trends in PFAS concentrations were observed. Mean concentrations of eight PFASs were higher in operating landfills (or landfill cells) accepting primarily municipal waste, compared to closed municipal landfills. Landfills accepting primarily construction and demolition wastes produced leachate that had higher mean PFAS concentrations than municipal landfills. Younger landfills appeared to have a higher burden of waste containing PFASs (or their precursors), as significant relationships (p<0.05) were observed between selected PFAS concentrations and landfill age. Increasing pH and total organic carbon (TOC) in leachate were associated with increased concentrations of several PFASs. Eight landfills discharged leachate to wastewater treatment plants (WWTPs). Estimated masses of PFASs discharged reached a maximum of 62g annually (PFHxA), with a national estimate reaching 31kg (PFHxA) annually. The practise of treating leachate at WWTPs allows redistribution of PFASs between the solid and liquid waste streams, although the contribution of leachate to the total load of PFASs entering WWTPs is minor compared to domestic waste water sources.

4.
J Hazard Mater ; 312: 55-64, 2016 07 15.
Article in English | MEDLINE | ID: mdl-27016666

ABSTRACT

The levels of perfluroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDDs) were studied in Australian landfill leachate and biosolids. Leachate was collected from 13 landfill sites and biosolids were collected from 16 wastewater treatment plants (WWTPs), across Australia. Perfluorohexanoate (PFHxA) (12-5700ng/L) was the most abundant investigated persistent, bioaccumulative and toxic (PBT) chemical in leachate. With one exception, mean concentrations of PFASs were higher in leachate of operating landfills compared to closed landfills. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane isomers (HBCDDs) were detected typically at operating landfills in comparatively lower concentrations than the PFASs. Decabromodiphenyl ether (BDE-209) (<0.4-2300ng/g) and perfluoroctanesulfonate (PFOS) (

Subject(s)
Environmental Monitoring , Flame Retardants/analysis , Fluorocarbons/analysis , Halogenated Diphenyl Ethers/analysis , Water Pollutants, Chemical/analysis , Australia , Waste Disposal Facilities
5.
Mar Pollut Bull ; 97(1-2): 56-66, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-26130525

ABSTRACT

The current investigation of marine water from 30 sites adjacent to stormwater outlets across the entire Sydney estuary is the first such research in Australia. The number of analytes detected were: 8/59 pharmaceutical compounds (codeine, paracetamol, tramadol, venlafaxine, propranolol, fluoxetine, iopromide and carbamazepine), 7/38 of the pesticides (2,4-dichlorophenoxyacetic acid (2,4-D), 3,4-dichloroaniline, carbaryl, diuron, 2-methyl-4-chlorophenoxyacetic acid (MCPA), mecoprop and simazine) and 0/3 of the personal care products (PCPs) analysed. An artificial sweetener (acesulfame) was detected, however none of the nine antibiotics analysed were identified. Sewage water is not discharged to this estuary, except infrequently as overflow during high-precipitation events. The presence of acesulfame (a recognised marker of domestic wastewater) and pharmaceuticals in water from all parts of the estuary after a dry period, suggests sewage water is leaking into the stormwater system in this catchment. The pesticides are applied to the environment and were discharged via stormwater to the estuary.


Subject(s)
Cosmetics/analysis , Food Additives/analysis , Pesticides/analysis , Water Pollutants, Chemical/analysis , Australia , Estuaries , Sewage , Wastewater
6.
Sci Total Environ ; 512-513: 177-184, 2015 Apr 15.
Article in English | MEDLINE | ID: mdl-25617997

ABSTRACT

This paper presents the first historical data on the occurrence of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDs) in estuarine sediment from Australia. Sediment cores and surficial sediment samples were collected from four locations within Sydney estuary, Australia. Large increases in concentrations were observed for all compounds between 1980 and 2014, especially for BDE-209 (representative usage of Deca-BDE commercial mixture), which was found in surficial sediment at an average concentration of 42 ng/g dry wt (21-65 ng/g dry wt). PBDE congeners representative of both the Penta- and Octa-BDE commercial mixtures (∑6PBDEs) were also found in their highest concentrations in surficial sediments (average: 1.3 ng/g dry wt; range: 0.65-2.5 ng/g dry wt). PBDE concentrations in surficial sediments were relatively high when compared with those presented in the available literature. This suggests that their input into the Sydney estuary has not decreased since their bans almost a decade earlier. After a sharp increase in the 1990s, HBCD concentrations peaked at an average of 3.5 ng/g dry wt (1.8-5.3 ng/g dry wt) in surficial samples. With global legislation on HBCDs allowing its usage for the next 10 years, it is expected that its input into the estuary is likely to continue.


Subject(s)
Estuaries , Geologic Sediments/chemistry , Halogenated Diphenyl Ethers/analysis , Hydrocarbons, Brominated/analysis , Water Pollutants, Chemical/analysis , New South Wales , Water Pollution, Chemical/statistics & numerical data
7.
Sci Total Environ ; 485-486: 497-507, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24742560

ABSTRACT

Polybrominated diphenyl ethers (PBDEs) and polybrominated dibenzo-p-dioxins and furans (PBDD/Fs) were detected in stack emissions from UK sinter plants. The sum of 36 PBDE congeners was measured at a mean concentration of 295 ng/N m(3) with a standard deviation of 96 ng/N m(3). The mean PBDD/F concentrations were 0.14 ng WHO-TEQ/m(3) (range=0.03-0.39). PBDD/F emission concentrations were approximately ten times lower than their PCDD/F homologues. To understand the possible formation mechanisms of brominated organic species in iron ore sintering, both full-scale and laboratory experiments using an experimental sintering process were carried out. A complete PBDE mass balance was undertaken for a full scale sinter plant showing that PBDEs were already present in the raw materials such as iron ores and coke breeze and that a significant proportion of the PBDE inputs were actually destroyed during the process. A number of controlled experiments were conducted using a laboratory-scale sintering apparatus (sinter pot). These were designed to investigate: (a) mass balance of PBDEs during sintering, (b) the relationship between the availability of bromide (as KBr) and PBDE emissions, and (c) the influence of the availability of both bromide and PBDEs on PBDD/F formation. As observed in the full scale plant, the PBDEs already present in the raw materials were mostly destroyed during the process (79-96%) for all sinter pot experiments. Increasing amounts of KBr in the raw sinter mix did not result in a significant increase in PBDE formation suggesting that there was no PBDE formation in sintering via de novo synthesis. No relationship was observed between PBDE inputs and PBDD/F emissions indicating that PBDEs did not act as precursors for PBDD/Fs formation. Finally, PBDD/F formation was enhanced substantially with increasing amounts of KBr suggesting that their formation mechanism was similar to that of PCDD/Fs via de novo synthesis.


Subject(s)
Air Pollutants/chemistry , Dioxins/chemistry , Furans/chemistry , Halogenated Diphenyl Ethers/chemistry , Iron/chemistry , Metallurgy , Air Pollutants/analysis , Dioxins/analysis , Furans/analysis , Halogenated Diphenyl Ethers/analysis , Models, Chemical
8.
Int J Dev Biol ; 43(1): 85-90, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10213086

ABSTRACT

A fundamental keystone of developmental biology has been the growing use of reporter genes in model transgenic systems. Their use has greatly facilitated investigations of cell lineage and cell fate in addition to aiding experiments aimed at determining patterns of gene expression, gene interaction and gene regulation. Through construction of transgenic mice, ubiquitously expressing human placental alkaline phosphatase (PLAP), we demonstrate the suitability of PLAP as a reporter gene for use in conjunction with, or as an alternative to, beta-galactosidase (lacZ). Our findings demonstrate that over-expression of PLAP has no adverse effects on mouse development or viability, despite a widespread pattern of expression. This technology provides a simple yet effective mechanism based on eukaryotic reporter gene technology to facilitate the identification of transgenic cells within complex in vivo systems.


Subject(s)
Genes, Reporter , Mice, Transgenic , Molecular Biology/methods , Proteins/metabolism , beta-Galactosidase/metabolism , Animals , Avian Sarcoma Viruses/metabolism , Cells, Cultured , Chimera , Embryo, Mammalian/anatomy & histology , Embryo, Mammalian/metabolism , Humans , Mice , Muscle, Skeletal/anatomy & histology , Muscle, Skeletal/physiology , Plasmids
9.
Proc Natl Acad Sci U S A ; 92(23): 10782-6, 1995 Nov 07.
Article in English | MEDLINE | ID: mdl-7479883

ABSTRACT

A systematic analysis of parthenogenetic (PG) cell fate within the central nervous system (CNS) was made throughout fetal development and neonatal and adult life. Chimeras were made between PG embryos carrying a ubiquitously expressed lacZ transgene and normal fertilized embryos. After detailed histological analysis, we find that the developmental potential of PG cells is spatially restricted to certain parts of the brain. PG cells are prevalent in telencephalic structures and are largely excluded from diencephalic structures, especially the hypothalamus. These spatial restrictions are established early in development. Behavioral studies with chimeras identified an increase in male aggression when the proportion of PG cells in the brain was high. These studies demonstrate that imprinted genes play key roles in development of the CNS and may be involved in behavior.


Subject(s)
Brain/growth & development , Genomic Imprinting , Parthenogenesis , Sexual Behavior, Animal , Aggression , Animals , Body Weight , Brain/cytology , Brain/embryology , Brain Stem/cytology , Brain Stem/growth & development , Chimera , Female , Frontal Lobe/cytology , Frontal Lobe/growth & development , Hypothalamus/cytology , Hypothalamus/growth & development , Male , Mice
10.
Am Heart J ; 123(3): 566-74, 1992 Mar.
Article in English | MEDLINE | ID: mdl-1539507

ABSTRACT

The effects of UL-FS 49, a specific bradycardic agent, on systemic hemodynamics, regional myocardial function (sonomicrometry, percentage of segment shortening), and regional coronary blood flow (radioactive microspheres) were studied in open-chest, anesthetized dogs with severe left circumflex coronary artery (LCX) stenosis. UL-FS 49 was administered as two sequential bolus injections of 0.25 mg/kg. Heart rate decreased from 149 +/- 13 beats/min to 102 +/- 6 and 77 +/- 4 beats/min after 0.25 and 0.5 mg/kg cumulative doses of UL-FS 49, respectively. The reduction in heart rate was not associated with any significant change in left ventricular pressure or mean arterial pressure, left ventricular dp/dt, or coronary vascular resistance. Similarly no hemodynamic changes occurred with atrial pacing to the initial heart rate. Application of an LCX stenosis of sufficient severity to produce a 50% reduction in mean LCX blood flow (44 +/- 4 to 22 +/- 2 ml/min) resulted in a significant reduction in the percentage of segment shortening in the ischemic zone (9.8 +/- 1.6% to 6.5 +/- 1.1%). The percentage of segment shortening in the ischemic zone progressively improved to 8.4 +/- 1.2% and 9.4 +/- 0.5% after 0.25 and 0.5 mg/kg UL-FS 49, respectively. Subepicardial perfusion in the ischemic zone was decreased and subendocardial perfusion was increased after administration of UL-FS 49. Consequently the ischemic zone endocardial/epicardial ratio increased from 0.43 +/- 0.08 to 1.12 +/- 0.22 and 1.48 +/- 0.32 with low and high doses of UL-FS 49.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Benzazepines/pharmacology , Cardiovascular Agents/pharmacology , Coronary Disease/physiopathology , Heart Rate/drug effects , Hemodynamics/drug effects , Animals , Coronary Circulation/drug effects , Depression, Chemical , Dogs , Female , Male , Myocardial Contraction/drug effects , Myocardium/metabolism , Oxygen Consumption/drug effects
11.
Dev Pharmacol Ther ; 8(2): 107-14, 1985.
Article in English | MEDLINE | ID: mdl-3888561

ABSTRACT

The effect of prenatally administered glucocorticoids on tubular reabsorption of beta 2-microglobulin and elimination half-life gentamicin have been investigated in newborn infants. beta 2-Microglobulin:creatinine ratio was significantly higher in preterm (4.43 +/- 0.88) than in full-term infants (0.89 +/- 0.42), but did not differ between infants exposed to betamethasone in utero and those who were not. Gentamicin pharmacokinetics did not differ between preterm infants who had or had not been exposed to betamethasone. It is therefore concluded that whilst prenatally administered glucocorticoids influence both pulmonary and hepatic maturation, they do not alter either renal tubular reabsorption of beta 2-microglobulin or glomerular filtration rate as estimated by gentamicin half-life.


Subject(s)
Betamethasone/pharmacology , Infant, Premature , Kidney/growth & development , Prenatal Exposure Delayed Effects , Adult , Birth Weight , Female , Gentamicins/metabolism , Gestational Age , Glomerular Filtration Rate , Half-Life , Humans , Infant, Newborn , Kidney Tubules/metabolism , Pregnancy , beta 2-Microglobulin/metabolism
12.
Dev Biol ; 52(2): 173-80, 1976 Sep.
Article in English | MEDLINE | ID: mdl-12194430

ABSTRACT

We report periodic movements during erection of Dictyostelium discoideum (Dd) sorocarps. Our observations lead to the working hypothesis that Dd sorocarp erection occurs by two superimposed processes: one periodic, with a modal period of 6 1/2 min, and one continuous. We tentatively identify the periodic process with cell movement into the apex of the Dd stalk, and the continuous process with cell vacuolation, together with stalk sheath extension.


Subject(s)
Dictyostelium/physiology , Animals , Dictyostelium/growth & development , Movement
13.
Biophys J ; 15(8): 753-63, 1975 Aug.
Article in English | MEDLINE | ID: mdl-167878

ABSTRACT

The design, calibration, and operation of a source of controlled amounts of cyclic AMP (c-AMP) are described. Typically, 1.5 s pulses containing 10(10)-10(-12) molecules of c-AMP can be delivered to a region about 10 mum in diameter on an agar plate. The resulting concentration profiles are given as functions of distance and time. The diffusion coefficient of c-AMP in agar was measured to be 0.97 times 10(-5) cm2-s-1 at 21 degrees C.


Subject(s)
Cyclic AMP , Agar , Dictyostelium/metabolism , Diffusion , Electrochemistry , Iontophoresis/instrumentation , Microelectrodes
14.
Biophys J ; 15(8): 765-75, 1975 Aug.
Article in English | MEDLINE | ID: mdl-167879

ABSTRACT

The microelectrode system described in the accompanying paper was used to investigate properties of fields of Dictyostelium discoideum amoebae in late interphase. Cells in the fields were competent to respond chemotactically to, and to relay, a c-AMP signal, but not to produce an aggregative signal autonomously. The experimental results are generally consistent with c-AMP being the sole compound required for chemotaxis and signal relaying. A periodic signal from the microelectrode can initiate and control aggregation and can complete with spontaneously arising aggregates. The electrode was used to measure the refractory period for relaying which decreases from 9 min or more to between 2 and 3 min with increasing developmental age, and to measure thresholds for chemotaxis and signal relaying. The results are discussed in relation to models for the control of aggregation in D. discoideum.


Subject(s)
Cyclic AMP/pharmacology , Dictyostelium/growth & development , Myxomycetes/growth & development , Dictyostelium/drug effects , Dose-Response Relationship, Drug , Electrochemistry , Microelectrodes , Time Factors
15.
Science ; 175(4019): 333-5, 1972 Jan 21.
Article in English | MEDLINE | ID: mdl-17814544

ABSTRACT

We have induced and controlled normal aggregation of Dictyostelium discoideum amoebas by electrophoretic release of pulses of cyclic adenosine monophosphate from a microelectrode. This has yielded information about the sequence of development of aggregation competences during interphase. We believe that modifications of the technique will have wide application in investigations of other developing systems.

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