Vascular Responses Among Adults Four Years Post Exposure to 6 Weeks of Smoke from the Hazelwood Coal Mine Fire

• Published in: Vascular health and risk management Vol. 18; pp. 253 - 265
• Main Authors: Mundisugih, Juan, Gao, Caroline X, Ikin, Jillian F, Abramson, Michael J, Brown, David, Biswas, Sinjini, Dewar, Elizabeth M, Liew, Danny, Stub, Dion
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 30-04-2022; Dove; Dove Medical Press
• Subjects: Adult; Adults; Air Pollutants - analysis; Air pollution; Analysis; C-reactive protein; C-Reactive Protein - analysis; Coal - analysis; Coal industry; Cross-Sectional Studies; Electrocardiogram; Electrocardiography; Environmental Exposure - analysis; Epidemiology; flow mediated dilatation; Humans; Mine accidents; Original Research; particulate matter; Particulate Matter - analysis; time to peak diameter; vascular responses; Wildfires; Australia; United Kingdom; epidemiology; particulate matter; time to peak diameter; air pollution; flow mediated dilatation; vascular responses
• ISSN: 1178-2048; 1176-6344; 1178-2048
• DOI: 10.2147/VHRM.S339439

Mega-wild fires are exposing large communities to weeks or months of high concentration smoke-related fine particulate air pollution (PM). However, little research has examined the long-term vascular responses from exposure to PM of this concentration and duration. We investigated whether level of exposure to 6 weeks of PM from the 2014 Hazelwood coal mine fire was associated with abnormal vascular responses approximately four years later.
A cross-sectional analysis was undertaken of 387 participants (225 exposed, 162 unexposed) aged 55-89 years, 3.5-4 years after the mine fire. The primary outcome was flow-mediated dilatation (FMD), with time to reach peak diameter as the secondary outcome. Other secondary markers included high-sensitivity C-reactive protein (hsCRP) and ischaemic Electrocardiogram (ECG) changes.
There was no evidence of a difference in FMD between participants with high, medium, low or no mine-fire related PM
exposure (4.09% vs 4.06% vs 4.02% vs 3.98%, respectively,
=0.99). Likewise, there was no difference in hsCRP or ischaemic ECG changes. In contrast, there was evidence of a difference in time to peak diameter (
=0.002) with more unexposed participants reaching peak diameter within 30 seconds (36%) compared to those who had high, medium, or low exposure (23%, 22%, 13%, respectively). Multivariate ordinal logistic regression analysis suggested that township, Morwell (exposed) vs Sale (unexposed), but not level of PM
exposure, was associated with delayed time to peak diameter (OR 2.71; 95% CI 1.56, 4.69). Smokers also had delayed time to peak diameter.
There was no association between level of exposure to PM
from the 6-week Hazelwood coal mine fire smoke event and reduced FMD, elevated hsCRP or ischaemic ECG four years later. Evidence of delayed time to peak diameter observed in adults from the exposed town, compared to an unexposed town, requires further investigation.