29 research outputs found

    Serum measures of hexabromocyclododecane (HBCDD) and polyborminated diphenyl ethers (PBDEs) in reproductive-aged women in the United Kingdom

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    We investigated the serum concentrations of two brominated flame retardants (BFRs) – polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD) –in 59 women aged between 23 and 42 from the United Kingdom. We also collected demographic data, including age, bodyweight and height in order to test for associations with BFR levels. Temporal and global differences were also assessed using previously published data.HBCDD was detected in 68% of samples with a mean concentration of 2.2 ng/g lipid (range =< 0.3–13 ng/g lipid). The dominant stereoisomer was α-HBCDD with an average contribution of 82% (0–100%) towards ΣHBCDD, was followed by γ-HBCDD (average contribution = 17%). PBDEs were detected in 95% of samples with a mean ∑PBDE (sum of BDEs −28, −47, −99, −100, −153, −154 and −183) concentration of 2.4 ng/g lipid (range = 2.5 since 2010. Whilst the human body burden appear to be decreasing, both PBDEs and HBCDD are still consistently detected in human serum, despite legislative action limiting their production and use. This highlights the need to continuously assess human exposure and the effectiveness of policy aimed at reducing exposure

    Rapid screening and identification of chemical hazards in surface and drinking water using high resolution mass spectrometry and a case-control filter

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    Access to clean, safe drinking water poses a serious challenge to regulators, and requires analytical strategies capable of rapid screening and identification of potentially hazardous chemicals, specifically in situations when threats to water quality or security require rapid investigations and potential response. This study describes a fast and efficient chemical hazard screening strategy for characterising trace levels of polar organic contaminants in water matrices, based on liquid chromatography high resolution mass spectrometry with post-acquisition 'case-control' data processing. This method allowed for a rapid response time of less than 24 h for the screening of target, suspect and non-target unknown chemicals via direct injection analysis, and a second, more sensitive analysis option requiring sample pre-concentration. The method was validated by fortifying samples with a range of pesticides, pharmaceuticals and personal care products (n = 46); with >90% of target compounds positively screened in samples at 1 ng mL(-1), and 46% at 0.1 ng mL(-1) when analysed via direct injection. To simulate a contamination event samples were fortified with compounds not present in the commercial library (designated 'non-target compounds'; fipronil and fenitrothion), tentatively identified at 0.2 and 1 ng mL(-1), respectively; and a compound not included in any known commercial library or public database (designated 'unknown' compounds; 8C1(-) perfluorooctanesulfonic acid), at 0.8 ng mL(-1). The method was applied to two 'real-case' scenarios: (1) the assessment of drinking water safety during a high-profile event in Brisbane, Australia; and (2) to screen treated, re-circulated drinking water and pre-treated (raw) water. The validated workflow was effective for rapid prioritisation and screening of suspect and non-target potential hazards at trace levels, and could be applied to a wide range of matrices and investigations where comparison of organic contaminants between an affected and control site and or timeframe is warranted. (C) 2017 Elsevier Ltd. All rights reserved

    Integrated collaborative care teams to enhance service delivery to youth with mental health and substance use challenges : Protocol for a pragmatic randomised controlled trial

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    Introduction: Among youth, the prevalence of mental health and addiction (MHA) disorders is roughly 20%, yet youth are challenged to access evidence-based services in a timely fashion. To address MHA system gaps, this study tests the benefits of an Integrated Collaborative Care Team (ICCT) model for youth with MHA challenges. A rapid, stepped-care approach geared to need in a youth-friendly environment is expected to result in better youth MHA outcomes. Moreover, the ICCT approach is expected to decrease service wait-times, be more youth-friendly and familyfriendly, and be more cost-effective, providing substantial public health benefits. Methods and analysis: In partnership with four community agencies, four adolescent psychiatry hospital departments, youth and family members with lived experience of MHA service use, and other stakeholders, we have developed an innovative model of collaborative, community-based service provision involving rapid access to needs-based MHA services. A total of 500 youth presenting for hospital-based, outpatient psychiatric service will be randomised to ICCT services or hospital-based treatment as usual, following a pragmatic randomised controlled trial design. The primary outcome variable will be the youth's functioning, assessed at intake, 6 months and 12 months. Secondary outcomes will include clinical change, youth/family satisfaction and perception of care, empowerment, engagement and the incremental cost-effectiveness ratio (ICER). Intent-to-treat analyses will be used on repeated-measures data, along with cost-effectiveness and cost-utility analyses, to determine intervention effectiveness. Ethics and dissemination: Research Ethics Board approval has been received from the Centre for Addiction and Mental Health, as well as institutional ethical approval from participating community sites. This study will be conducted according to Good Clinical Practice guidelines. Participants will provide informed consent prior to study participation and data confidentiality will be ensured. A data safety monitoring panel will monitor the study. Results will be disseminated through community and peer-reviewed academic channels

    Self-Compassion, emotion regulation and stress among australian psychologists: Testing an emotion regulation model of self-compassion using structural equation modeling

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    Psychologists tend to report high levels of occupational stress, with serious implications for themselves, their clients, and the discipline as a whole. Recent research suggests that selfcompassion is a promising construct for psychologists in terms of its ability to promote psychological wellbeing and resilience to stress; however, the potential benefits of self-compassion are yet to be thoroughly explored amongst this occupational group. Additionally, while a growing body of research supports self-compassion as a key predictor of psychopathology, understanding of the processes by which self-compassion exerts effects on mental health outcomes is limited. Structural equation modelling (SEM) was used to test an emotion regulation model of self-compassion and stress among psychologists, including postgraduate trainees undertaking clinical work (n = 198). Self-compassion significantly negatively predicted emotion regulation difficulties and stress symptoms. Support was also found for our preliminary explanatory model of self-compassion, which demonstrates the mediating role of emotion regulation difficulties in the self-compassion-stress relationship. The final self-compassion model accounted for 26.2% of variance in stress symptoms. Implications of the findings and limitations of the study are discussed

    The neurobiology and age-related prevalence of the epsilon 4 allele of apolipoprotein E in Alzheimer's disease cohorts

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    le Alzheimer's disease (AD) is a progressive neurodegenerative disease characterised by amyloid beta (A beta) plaques and tau neurofibrillary tangles in the brain. Human apolipoprotein E (ApoE) is a lipid transport protein coded by the polymorphic APOE gene, with three major alleles: epsilon 2, epsilon 3 and epsilon 4. After age, the epsilon 4 allele is the greatest risk factor for developing sporadic AD, conferring an increased risk of 3-4 and 8-12 times for one or two copies of the allele, respectively. This risk is reported to vary by demographic factors including sex, ethnicity and geography. In order to understand the risk of ApoE epsilon 4 in relation to age, the primary risk factor for developing AD, we need to understand how the prevalence of APOE genotypes changes with age. Here, we present the first data on age-related prevalence of APOE epsilon 4 in AD in three AD cohorts in Australia and the USA. There is a significant association between age and epsilon 4 prevalence, particularly for epsilon 4 homozygotes, such that as age increases the prevalence of epsilon 4 decreases. Further studies on a random, population-based samp of the population are needed to provide more generalizable data, particularly in the > 90-year-old age group

    Assessing exposures to emerging environmental contaminants in children

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    The period of developmental vulnerability to toxicants begins at conception and extends through gestation, parturition, infanthood and childhood to adolescence. The concern is that children: (1) may experience quantitatively and qualitatively different exposures, and (2) may have different sensitivity to chemical pollutants. Traditional toxicological studies are inappropriate for assessing the results of chronic exposure at very low levels during critical periods of development. This paper will discuss (1) the health effects associated with exposure to selected emerging organic pollutants, including brominated flame retardants, perfluorinated compounds, organophosphate pesticides and bisphenol A; (2) difficulties in monitoring these substances in children, and (3) suggest techniques and strategies for overcoming these difficulties. Such biomonitoring data can be used to identify where policies should be directed in order to reduce exposure, and to document policies that have successfully reduced exposure

    Age-related trends in urinary excretion of bisphenol A in Australian children and adults : evidence from a pooled sample study using samples of convenience

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    Bisphenol A (BPA or 4,4’-(propane-2,2-diyl)diphenol) is a chemical intermediate in the production of polycarbonate and epoxy resins, and used in a wide range of applications. BPA has attracted significant attention in the past decade due to its frequency of detection in human populations worldwide, demonstrated animal toxicity and potential impact on human health, particularly during critical periods of development. The aim of this study was to perform a preliminary assessment of age-related trends in urinary concentration and to estimate daily excretion of BPA in Australian children (aged (>0 – <5 years) and adults (≥15 – <75 years). This was achieved using 79 samples pooled by age and gender, created from 868 individual samples of convenience collected as part of routine, community-based pathology testing. Total BPA was analyzed using online-SPE-LC-MS/MS and detected in all samples with a range of 0.65 – 265 ng/ml. No significant differences were observed between males and females. A urine flow model was constructed from published values and used to provide an estimate of daily excretion per unit bodyweight for each pooled sample. The daily excretion estimates ranged from 26.2 – 18200 ng/kg-d for children; and 20.1 – 165 ng/kg-d for adults. Urinary concentrations and estimated excretion rates were inversely associated with age, and estimated daily excretion rates in infants and young children were significantly higher than in adults (geometric mean: 107 and 47.0 ng/kg-d, respectively). Higher excretion of BPA in children may be explained by their higher food consumption relative to body weight compared to adults and adolescents, and may also reflect alternative exposure pathways and sources.\ud \ud Keywords: bisphenol A, biomonitoring, children, urine flow, Australi

    Age as a determinant of phosphate flame retardant exposure of the Australian population and identification of novel urinary PFR metabolites

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    The demand for alternative flame retardant materials such as phosphate flame retardants and plasticizers (PFRs) is increasing, although little is known of their possible effects on human health and development. To date, no information on the exposure of children or general Australian population to PFRs is available. The objectives of this study were to characterize the average levels and age-related patterns of PFR metabolites in urine in the general Australian population and to identify novel hydroxylated PFR metabolites in urine. Surplus pathology urine samples from Queensland, Australia were stratified and pooled by age and sex (3224 individuals aged 0 to 75 years into 95 pools) according to two different pooling strategies at two different time periods. Samples were analyzed by solid phase extraction and liquid chromatography–tandem mass spectrometry following enzymatic treatment. Nine PFR metabolites were measured in the Australian population, including the first report of a hydroxylated metabolite of TCIPP (BCIPHIPP). Diphenyl phosphate (DPHP), BCIPHIPP and bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) were detected in > 95% of samples. DPHP, a metabolite of aryl-PFRs, was found in several samples at levels which were one order of magnitude higher than previously reported (up to 730 ng/mL). Weighted linear regression revealed a significant negative association between log-normalized BDCIPP and DPHP levels and age (p < 0.001). Significantly greater levels of BDCIPP and DPHP were found in children's urine compared with adults, suggesting higher exposure to PFRs in young children. BCIPHIPP was identified for inclusion in future PFR biomonitoring studies
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