Output list
Journal article
Published 2024
Journal of epidemiology and community health (1979), 78, 11, 705 - 712
Background: Australia has experienced extreme fire weather in recent years. Information on the impact of fine particulate matter (PM 2.5 ) from landscape fires (LFs) on cardiorespiratory hospital admissions is limited.
Methods: We conducted a population-based time series study to assess associations between modelled daily elevated PM 2.5 at a 1.5×1.5 km resolution using a modified empirical PM 2.5 exposure model during LFs and hospital admissions for all-cause and cause-specific respiratory and cardiovascular diseases for the study period (2015–2017) in Perth, Western Australia. Multivariate Poisson regressions were used to estimate cumulative risk ratios (RR) with lag effects of 0–3 days, adjusted for sociodemographic factors, weather and time.
Results: All-cause hospital admissions and overall cardiovascular admissions increased significantly across each elevated PM 2.5 concentration on most lag days, with the strongest associations of 3% and 7%, respectively, at the high level of ≥12.60 µg/m3 on lag 1 day. For asthma hospitalisation, there was an excess relative risk of up to 16% (RR 1.16, 95% CI 1.00 to 1.35) with same-day exposure for all people, up to 93% on a lag of 1 day in children and up to 52% on a lag of 3 days in low sociodemographic groups. We also observed an increase of up to 12% (RR 1.12, 95% CI 1.02 to 1.24) for arrhythmias on the same exposure day and with over 154% extra risks for angina and 12% for heart failure in disadvantaged groups.
Conclusions: Exposure to elevated PM 2.5 concentrations during LFs was associated with increased risks of all-cause hospital admissions, total cardiovascular conditions, asthma and arrhythmias.
Journal article
Published 2022
Journal of Epidemiology and Community Health
Background Landscape fires (LFs) are the main source of elevated particulate matter (PM2.5) in Australian cities and towns. This study examined the associations between daily exposure to fine PM2.5 during LF events and daily emergency department attendances (EDA) for all causes, respiratory and cardiovascular outcomes. Methods Daily PM2.5 was estimated using a model that included PM2.5 measurements on the previous day, remotely sensed aerosols and fires, hand-drawn tracing of smoke plumes from satellite images, fire danger ratings and the atmosphere venting index. Daily PM2.5 was then categorised as high (≥99th percentile), medium (96th–98th percentile) and low (≤95th percentile). Daily EDA for all-cause and cardiorespiratory conditions were obtained from the Western Australian Emergency Department Data Collection. We used population-based cohort time-series multivariate regressions with 95% CIs to assess modelled daily PM2.5 and EDA associations from 2015 to 2017. We estimated the lag-specific associations and cumulative risk ratios (RR) at lags of 0–3 days, adjusted for sociodemographic factors, weather and time. Results All-cause EDA and overall cardiovascular presentations increased on all lagged days and up to 5% (RR 1.05, 95% CI 1.03 to 1.06) and 7% (RR 1.07, 95% CI 1.01 to 1.12), respectively, at the high level. High-level exposure was also associated with increased acute lower respiratory tract infections at 1 (RR 1.19, 95% CI 1.10 to 1.29) and 3 (RR 1.17, 95% CI 1.10 to 1.23) days lags and transient ischaemic attacks at 1 day (RR 1.25, 95% CI 1.02 to 1.53) and 2 (RR 1.20, 95% CI 1.01 to 1.42) days lag. Conclusions Exposure to PM2.5 concentrations during LFs was associated with an increased risk of all-cause EDA, overall EDA cardiovascular diseases, acute respiratory tract infections and transient ischaemic attacks.
Journal article
Published 2020
Scandinavian Journal of Work, Environment & Health, 46, 4, 417 - 428
Objectives: This prospective birth cohort study evaluated the effect of occupational exposure to endocrine disrupting chemicals (EDC) during pregnancy on inadequate fetal growth as measured by small-for-gestational age (SGA) and inadequate fetal growth measured by percentage of optimal birth weight (POBW). The study also identified the maternal characteristics associated with an increased risk of exposure to EDC. Methods: We studied 4142 pregnant women who were in paid employment during pregnancy and participated in a population-based, prospective 2007–2011 birth cohort study, the Born in Bradford Study, with an estimated participation of 80%. Job titles were coded at 26–28 weeks` gestation at a 4-digit level according to 353 unit groups in the 2000 UK Standard Occupational Classification. They were then linked to expert judgment on exposure to each of ten EDC groups as assessed through a job exposure matrix (JEM). We performed generalized estimation equation modelling by a modified Poisson regression to assess the risk of POBW and SGA associated with an increased risk of chemical exposures. Results: The frequency of POBW<85 significantly increased for mothers exposed to pesticides [adjusted risk ratio (RRadj) 3.72, 95% confidence interval (CI) 1.40–9.91] and phthalates (RRadj 3.71, 95% CI 1.62–8.51). There was a 5-fold increase risk of SGA for mothers exposed to pesticides (RRadj 5.45, 95% CI 1.59–18.62). Veterinary nurses and horticultural trades were most frequently associated with exposure to pesticides while hairdressers, beauticians, and printing machine minders were associated with phthalates. Conclusion: Maternal occupational exposure to estimated concentrations of pesticides and phthalates is associated with impaired fetal growth.
Journal article
Published 2016
Fertility and Sterility, 106, 3, 704 - 709.e1
Objective
To describe trends in age-specific incidence rates of female sterilization (FS) procedures in Western Australia and to evaluate the effects of the introduction of government-subsidized contraceptive methods and the implementation of the Australian government's baby bonus policy on FS rates.
Design
Population-based retrospective descriptive study.
Setting
Not applicable.
Patient(s)
All women ages 15–49 undergoing an FS procedure during the period January 1, 1990, to December 31, 2008 (n = 47,360 procedures).
Intervention(s)
Records from statutory statewide data collections of hospitals separations and births were extracted and linked.
Main Outcome Measure(s)
Trends in FS procedures and the influence on these trends of the introduction of government policies: subsidization of long-acting reversible contraceptives (Implanon and Mirena) and the Australian baby bonus initiative.
Result(s)
The annual incidence rate of FS procedures declined from 756.9 per 100,000 women in 1990 to 155.2 per 100,000 women in 2008. Compared with the period 1990–1994, women ages 30–39 years were 47% less likely (rate ratio [RR] = 0.53; 95% confidence interval [CI], 0.39–0.72) to undergo sterilization during the period 2005–2008. Adjusting for overall trend, there were significant decreases in FS rates after government subsidization of Implanon (RR = 0.89; 95% CI, 0.82–0.97) and Mirena (RR = 0.81; 95% CI, 0.73–0.91) and the introduction of the baby bonus (RR = 0.70; 95% CI, 0.61–0.81).
Conclusion(s)
Rates of female sterilization procedures in Western Australia have declined substantially across all age groups in the last two decades. Women's decisions to undergo sterilization procedures may be influenced by government interventions that increase access to long-term reversible contraceptives or encourage childbirth.
Journal article
A study of handling cytotoxic drugs and risk of birth defects in offspring of female veterinarians
Published 2014
International Journal of Environmental Research and Public Health, 11, 6, 6216 - 6230
We examined the association of occupational exposure to handling cytotoxic drugs at work with risk of birth defects among a cohort of female veterinarians. This study is a follow up survey of 321 female participants (633 pregnancies) who participated in the Health Risks of Australian Veterinarian project. Data on pregnancies and exposure during each pregnancy was obtained by self-administered mailed questionnaire. Female veterinarians handling cytotoxic drugs during their pregnancy had a two-fold increased risk of birth defects in their offspring (RR = 2.08, 95% CI (1.05–4.15)). Results were consistent in subgroup analysis of those who graduated during the period of 1961 to 1980 (RR = 5.04, 95% CI (1.81, 14.03) and in those working specifically in small and large animal practice. There was no increased risk in the subgroup that graduated after 1980. Women with unplanned pregnancies were more likely to handle cytotoxic drugs on a daily basis (RR = 1.86, 95% CI, 1.00–3.48) and had a higher increased risk of birth defects than those who planned their pregnancies in recent graduates and in those who worked specifically in small animal practice (RR = 2.53, 95% CI, 1.18–5.42). This study suggests that the adverse effects of handling cytotoxic drugs in pregnant women may include an increased risk of birth defects. Pregnancy intention status is an important health behavior and should be considered in prenatal programs.
Journal article
Mental health in female veterinarians: Effects of working hours and having children
Published 2013
Australian Veterinary Journal, 91, 4, 123 - 130
Background Personal, interpersonal and organisational factors have been suggested as possible causes of stress, anxiety and depression for veterinarians. We used established psychological scales to measure (1) levels of distress and work-related stress (anxiety and depression) and (2) the demographic and work characteristics of female veterinarians in relation to anxiety, depression and mental health. Methods A national cross-sectional survey of a cohort population was conducted and self-administered questionnaires were received from 1017 female veterinarians who completed the mental health section of the survey. Using linear and logistic regression analyses, we examined demographic and work-related factors associated with overall stress measured by the General Health Questionnaire scale and the Affective Well-Being scale (Anxiety-Contentment Axis and Depression-Enthusiasm Axis). Results More than one-third (37%) of the sample was suffering ‘minor psychological distress’, suggesting the stressful nature of veterinary practice. Women with two or more children had less anxiety and depression compared with those who had never been pregnant or were childless. Longer working hours were associated with increased anxiety and depression in female veterinarians overall and in stratified samples of women with and without children. Conclusion Among the work characteristics of veterinary practice, long working hours may have a direct effect on a veterinarian's health in terms of anxiety, depression and mental health. The finding also indicates that women with two or more children have less anxiety and depression than women who have never been pregnant or childless women.
Journal article
Published 2010
Paediatric and Perinatal Epidemiology, 25, 2, 172 - 191
Over the last decade, there has been growing concern about the possible health effects, including a number of adverse reproductive outcomes, from pesticide exposure of people living near agricultural fields. This systematic review evaluates the current epidemiological evidence on the association between living near agricultural pesticide applications and adverse reproductive outcomes, including congenital malformations, stillbirth, intrauterine growth retardation (IUGR), low birthweight, preterm birth and miscarriage. We identified and reviewed 25 studies from a systematic search of the main scientific databases and other sources published in 1950–2007. Study methods and main results were summarised and tabulated according to the year of study, design and type of adverse reproductive outcome. The levels of evidence for reproductive toxicity in humans contributed by each study were assessed and the main limitations associated with these studies discussed. Residential proximity to agricultural pesticide applications may be an important source of ambient environmental exposure, but because of the underlying methodological difficulties, the strength of evidence for its relationship with adverse reproductive outcomes is generally weak and varied between outcomes. The evidence suggested an association for congenital malformations, but because of methodological limitations, such as poor exposure measurement and potentially inadequate control of confounding, a firm conclusion remains beyond reach. For the other outcomes (stillbirth, IUGR, low birthweight, preterm birth and miscarriage) the evidence for any associations was equivocal at best, but some leads warrant further investigation. Improved exposure assessment methods are needed to obtain a more reliable assessment of any risks.
Journal article
Significant injuries in Australian veterinarians and use of safety precautions
Published 2009
Occupational Medicine, 59, 5, 327 - 333
Background: A high injury prevalence has been reported among veterinarians. Studies describing the factors associated with injury have been limited. Aims: To describe the characteristics of serious injuries and the use of safety precautions at the time of injury in Australian veterinarians. Methods: Graduates in veterinary medicine from Australian universities completed questionnaires asking about injuries during their professional career including type of injury and circumstances during which injury occurred. Results: A total of 2188 significant injuries were reported. Injuries were most frequently sustained on farms (55%) and associated with undertaking procedural activities (37%) and examining and moving animals (37%). The hand (33%) was the commonest site involved. Injuries to the head and face regions accounted for 15% of all injuries. The most frequent injuries sustained were open wounds (36%), fractures and dislocations (27%) and soft tissue bruising (12%). There were 63 reports of intracranial injury and 19 traumatic amputations reported. Bites, kicks or strikes, animal contact and cutting or scratching were the most frequent mechanisms of injury reported. The major factors reported in association with injury were cattle (22%), horses (21%), dogs (20%) and cats (8%). Fifty-five per cent of veterinarians reported the use of safety precautions at the time of injury. Conclusions: Veterinarians are a high-risk group for significant injury from animal contacts. The reported use of safety measures and their effectiveness when used by veterinarians appear less than optimal. Further efforts aimed at addressing injury prevention may include developing and implementing improved safe handling practices and safety precautions.
Journal article
Birth defects in offspring of female veterinarians
Published 2009
Journal of Occupational and Environmental Medicine, 51, 5, 525 - 533
Objectives: To investigate the risk of birth defects in offspring of female veterinarians exposed to occupational hazards such as radiation, anesthetic gases, and pesticides in veterinary practice. Methods: The Health Risks of Australian Veterinarians project was conducted as a questionnaire-based survey of all graduates from Australian veterinary schools during the 40-year period 1960–2000. Results: In a multiple logistic regression controlling for the potential confounders, the study showed an increased risk of birth defects in offspring of female veterinarians after occupational exposure to high dose of radiation (taking more than 10 x-ray films per week, odds ratio: 5.73 95% CI: 1.27 to 25.80) and an increase risk of birth defects after occupational exposure to pesticides at least once per week (odds ratio: 2.39 95% CI: 0.99 to 5.77) in veterinarians exclusively working in small animal practice. Conclusion: Female veterinarians should be informed of the possible reproductive effects of occupational exposures to radiation and pesticides.
Journal article
Published 2009
Obstetrics & Gynecology, 113, 5, 1008 - 1017
OBJECTIVE: To examine whether occupational hazards such as anesthetic gases, radiation, pesticides, and working hours in veterinary practice are associated with preterm delivery (before 37 weeks of gestation) in female veterinarians. METHODS: The Health Risks of Australian Veterinarians project was conducted as a questionnaire-based survey of all graduates of Australian veterinary schools during the 40-year period 1960–2000. Approximately 1,200 female veterinarians participated in the survey. Pregnancy was defined as the unit of analysis. We restricted analyses to pregnancies of those women who reported being employed when the pregnancy began and were working only in clinical practice. Of 1,355 pregnancies in total in the file, 744 pregnancies were eligible for the final analysis. RESULTS: The prevalence of preterm birth in women exposed to unscavenged anesthetic gases was 7.3% compared with 5.7% in the general population. In a Cox proportional hazards model controlling for the potential confounders, there was a significant 2.5-fold increase (hazard ratio 2.56, 95% confidence interval [CI] 1.33–4.91) in the risk of preterm delivery in women exposed to unscavenged anesthetic gases for 1 or more hours per week compared with the unexposed group (women who did not perform surgery and those who performed surgery in the presence of a scavenger system). A dose–response relation also was found within this group when exposure was divided into finer categories. There was also a strong and monotonic increase in risk of preterm delivery and the number of hours worked per week with veterinarians working more than 45 hours a week (hazard ratio 3.69, 95% CI 1.40–9.72) compared with those working fewer than 45 hours per week. CONCLUSION: Long working hours and performing surgery in the absence of a scavenger system for anesthetic gases are important risk factors for preterm birth in female veterinarians.