Holt Nicolette R, Smith Catherine L, Gao Caroline X, Borg Brigitte, Lane Tyler, Brown David, Ikin Jillian, Makar Annie, McCrabb Thomas, Thomas Mikayla, Nilsen Kris, Thompson Bruce R, Abramson Michael J
School of Public Health and Preventive Medicine, Monash University Faculty of Medicine Nursing and Health Sciences, Melbourne, Victoria, Australia.
Department of Respiratory Medicine, Royal Melbourne Hospital, Parkville, Victoria, Australia.
BMJ Open Respir Res. 2024 Dec 18;11(1):e002539. doi: 10.1136/bmjresp-2024-002539.
The 2014 Hazelwood coal mine fire exposed residents in nearby Morwell to high concentrations of particulate matter <2.5 µm (PM) for approximately 6 weeks. This analysis aimed to evaluate the long-term impact on respiratory health.
Adults from Morwell and the unexposed town of Sale completed validated respiratory questionnaires and performed spirometry, gas transfer and oscillometry 3.5-4 years (round 1) and 7.3-7.8 years (round 2) after the fire. Individual PM exposure levels were estimated using chemical transport models mapped onto participant-reported time-location data. Mixed-effects regression models were fitted to analyse associations between PM exposure and outcomes, controlling for key confounders.
From 519 (346 exposed) round 1 participants, 329 (217 exposed) participated in round 2. Spirometry and gas transfer in round 2 were mostly lower compared with round 1, excepting forced vital capacity (FVC) (increased) and forced expiratory volume in 1 second (minimal change). The effect of mine fire-related PM exposure changed from a negative effect in round 1 to no effect in round 2 for both pre-bronchodilator (p=0.005) and post-bronchodilator FVC (p=0.032). PM was not associated with gas transfer in either round. For post-bronchodilator reactance and area under the curve, a negative impact of PM in round 1 showed signs of recovery in round 2 (both p<0.001).
In this novel study evaluating long-term respiratory outcomes after medium-duration high concentration PM exposure, the attenuated associations between exposure and respiratory function may indicate some recovery in lung function. With increased frequency and severity of landscape fires observed globally, these results inform public health policies and planning.
2014年黑泽尔伍德煤矿火灾使附近莫韦尔的居民暴露于高浓度的小于2.5微米颗粒物（PM）中约6周。本分析旨在评估对呼吸健康的长期影响。
来自莫韦尔及未受影响的城镇塞尔的成年人在火灾发生3.5 - 4年（第一轮）和7.3 - 7.8年（第二轮）后完成了经过验证的呼吸问卷，并进行了肺活量测定、气体交换测定和振荡法测定。使用化学传输模型根据参与者报告的时间 - 地点数据估算个体PM暴露水平。采用混合效应回归模型分析PM暴露与结果之间的关联，并控制关键混杂因素。
第一轮的519名参与者（346名暴露者）中，329名（217名暴露者）参与了第二轮。与第一轮相比，第二轮的肺活量测定和气体交换大多降低，但用力肺活量（FVC）（增加）和一秒用力呼气量（变化极小）除外。对于支气管扩张剂使用前（p = 0.005）和支气管扩张剂使用后FVC（p = 0.032），与煤矿火灾相关的PM暴露的影响从第一轮的负面影响变为第二轮的无影响。两轮中PM均与气体交换无关。对于支气管扩张剂使用后的电抗和曲线下面积，第一轮中PM的负面影响在第二轮显示出恢复迹象（p均<0.001）。
在这项评估中等时长高浓度PM暴露后长期呼吸结果的创新性研究中，暴露与呼吸功能之间减弱的关联可能表明肺功能有所恢复。鉴于全球范围内景观火灾的频率和严重程度增加，这些结果为公共卫生政策和规划提供了参考。
