Search

Background and aim: There are few long-term studies of respiratory health effects of landscape fires, despite increasing frequency and intensity due to climate change. We investigated the association between exposure to coal mine fire PM2.5 and fractional exhaled nitric oxide (FeNO) concentration 7.5 years later. Methods: Adult residents of Morwell, who were exposed to the 2014 Hazelwood mine fire over 6 weeks, and unexposed residents of Sale, participated in the Hazelwood Health Study Respiratory Stream in 2021, including measurements of FeNO concentration, a marker of eosinophilic airway inflammation. Individual exposure to coal mine fire PM2.5 was modelled and mapped to time-location diaries. The effect of exposure to PM2.5 on log-transformed FeNO in exhaled breath was investigated using multivariate linear regression models in the entire sample and stratified by potentially vulnerable subgroups. Results: A total of 326 adults (mean age: 57 years) had FeNO measured. The median FeNO level (interquartile range [IQR]) was 17.5 [15.0] ppb, and individual daily exposure to coal mine fire PM2.5 was 7.2 [13.8] µg/m3. We did not identify evidence of association between coal mine fire PM2.5 exposure and FeNO in the general adult sample, nor in various potentially vulnerable subgroups. The point estimates were consistently close to zero in the total sample and subgroups. Conclusion: Despite previous short-term impacts on FeNO and respiratory health outcomes in the medium term, we found no evidence that PM2.5 from the Hazelwood coal mine fire was associated with any long-term impact on eosinophilic airway inflammation measured by FeNO levels. [ABSTRACT FROM AUTHOR]

Background: In 2014, the Hazelwood coalmine fire shrouded the regional Australian town of Morwell in smoke and ash for 6 weeks. One of the fire's by‐products, PM2.5, is associated with an increased risk of COVID‐19 and severe disease. However, it is unclear whether the effect persisted for years after exposure. In this study, we surveyed a cohort established prior to the pandemic to determine whether PM2.5 from the coalmine fire increased long‐term vulnerability to COVID‐19 and severe disease. Methods: From August to December 2022, 612 members of the Hazelwood Health Study's adult cohort, established in 2016/17, participated in a follow‐up survey that included standardized items to capture COVID‐19 cases, as well as questions about hospitalization and vaccinations. Associations were evaluated in crude and adjusted logistic regression models. Results: A total of 268 (44%) participants self‐reported or met symptom criteria for having had COVID‐19 at least once. All models found a positive association, with odds of COVID‐19 increasing by between 4% and 30% for a 10 μg/m3 increase in coalmine fire‐related PM2.5 exposure. However, the association was significant in only 2 of the 18 models. There were insufficient hospitalizations to examine severity (n = 7; 1%). Conclusion: The findings are inconclusive on the effect of coalmine fire‐related PM2.5 exposure on long‐term vulnerability to COVID‐19. Given the positive association that was robust to modelling variations as well as evidence for a causal mechanism, it would be prudent to treat PM2.5 from fire events as a long‐term risk factor until more evidence accumulates. Surveying a cohort established before the pandemic, we investigated long‐term COVID‐19 vulnerability due to coalmine fire smoke exposure. There was a positive but generally non‐significant association between PM2.5 and COVID‐19. It would therefore be prudent to treat extreme but discrete coalmine fire smoke as a long‐term COVID‐19 risk factor. See relatededitorial [ABSTRACT FROM AUTHOR]

The 2014 Hazelwood coal mine fire in the Latrobe Valley, Australia, distributed toxic smoke into surrounding communities over 45 days. This study investigated risk and protective factors associated with four trajectories of posttraumatic distress (resilient, recovery, delayed‐onset, chronic) among exposed adults. Participants (N = 709) completed surveys in 2016–2017 and 2019–2020 assessing mine fire–related particulate matter (PM2.5) exposure; sociodemographic, physical, and mental health variables; and exposure to other traumatic and recent stressful events. Mine fire–related posttraumatic distress was measured using the IES‐R; trajectories were determined according to established clinical significance thresholds. Relative risk ratios (RRRs) were generated from multivariate multinomial regressions. The resilient trajectory was most common (77.0%). The chronic trajectory (8.5%) was associated with loneliness, RRR = 2.59, 95% CI [1.30, 5.16], and physical health diagnoses, RRR = 2.31, 95% CI [1.32, 4.02]. The delayed‐onset trajectory (9.1%) was associated with multiple recent stressful events, RRR = 2.51, 95% CI [1.37, 4.59]; mental health diagnoses, RRR = 2.30, 95% CI [1.25, 4.24]; loneliness, RRR = 2.05, 95% CI [1.09, 3.88]; and male gender, RRR = 2.01, 95% CI [1.18, 3.44]. Socioeconomic advantage protected against chronic, RRR = 0.68, 95% CI [0.53, 0.86], and delayed‐onset trajectory membership, RRR = 0.68, 95% CI [0.50, 0.94]; social support protected against chronic trajectory membership, RRR = 0.67, 95% CI [0.49, 0.92]. PM2.5 exposure did not determine trajectory. These findings enhance understanding of longer‐term posttraumatic responses to large‐scale smoke events and can inform mental health initiatives within at‐risk communities. [ABSTRACT FROM AUTHOR]

In 2014, a fire at an open cut coal mine in South-eastern Australia burned for about 6 weeks. Residents of the adjacent town were exposed to high levels of fine particulate matter (PM2.5) during this period. Three and a half years after the event, this study aimed to investigate potential long-term impacts of short-term exposure to coal mine fire smoke on asthma. A cross-sectional analysis was undertaken in a group of exposed participants with asthma from Morwell (n = 165) and a group of unexposed participants with asthma from the control town of Sale (n = 64). Exposure was determined by modeled PM2.5 data for the mine fire period. Respiratory symptoms were assessed with a validated respiratory health questionnaire and symptom severity score. Asthma control was assessed with a validated questionnaire. Lung function testing included spirometry, bronchodilator response, and fraction of exhaled nitric oxide. There was no evidence that exposed participants had more severe asthma symptoms, worse lung function, or more eosinophilic airway inflammation than unexposed participants. However, there was some evidence that Morwell participants had more uncontrolled than well-controlled asthma, compared to the participants from Sale (adjusted relative risk ratio 2.71 95% CI: 1.02, 7.21, p =.046). Three and a half years after exposure, coal mine fire smoke did not appear to be associated with more severe asthma symptoms or worse lung function but might be associated with poorer asthma control. [ABSTRACT FROM AUTHOR]

Due to climate change, catastrophic events such as landscape fires are increasing in frequency and severity. However, relatively little is known about the longer-term mental health outcomes of such events. Follow-up was conducted of 709 adults exposed to smoke from the 2014 Hazelwood mine fire in Morwell, Victoria, Australia. Participants completed two surveys evaluating posttraumatic distress, measured using the Impact of Events Scale-Revised (IES-R), three and six years after the mine fire. Mixed-effects regression models were used to evaluate longitudinal changes in distress. IES-R total scores increased on average by 2.6 points (95%CI: 1.2 to 3.9 points) between the two survey rounds, with increases across all three posttraumatic distress symptom clusters, particularly intrusive symptoms. This increase in distress was evident across all levels of fine particulate matter (PM2.5) exposure to the mine fire smoke. Age was an effect modifier between mine fire PM2.5 exposure and posttraumatic distress, with younger adults impacted more by exposure to the mine fire. Greater exposure to PM2.5 from the mine fire was still associated with increased psychological distress some six years later, with the overall level of distress increasing between the two survey rounds. The follow-up survey coincided with the Black Summer bushfire season in south-eastern Australia and exposure to this new smoke event may have triggered distress sensitivities stemming from exposure to the earlier mine fire. Public health responses to disaster events should take into consideration prior exposures and vulnerable groups, particularly younger adults. [ABSTRACT FROM AUTHOR]