Peat Bog Wildfire Smoke Exposure in Rural North Carolina Is Associated with Cardiopulmonary Emergency Department Visits Assessed through Syndromic Surveillance

Abstract

Background: In June 2008, burning peat deposits produced haze and air pollution far in excess of National Ambient Air Quality Standards, encroaching on rural communities of eastern North Carolina. Although the association of mortality and morbidity with exposure to urban air pollution is well established, the health effects associated with exposure to wildfire emissions are less well understood.Objective: We investigated the effects of exposure on cardiorespiratory outcomes in the population affected by the fire.Methods: We performed a population-based study using emergency department (ED) visits reported through the syndromic surveillance program NC DETECT (North Carolina Disease Event Tracking and Epidemiologic Collection Tool). We used aerosol optical depth measured by a satellite to determine a high-exposure window and distinguish counties most impacted by the dense smoke plume from surrounding referent counties. Poisson log-linear regression with a 5-day distributed lag was used to estimate changes in the cumulative relative risk (RR).Results: In the exposed counties, significant increases in cumulative RR for asthma [1.65 (95% confidence interval, 1.25–2.1)], chronic obstructive pulmonary disease [1.73 (1.06–2.83)], and pneumonia and acute bronchitis [1.59 (1.07–2.34)] were observed. ED visits associated with cardiopulmonary symptoms [1.23 (1.06–1.43)] and heart failure [1.37 (1.01–1.85)] were also significantly increased.Conclusions: Satellite data and syndromic surveillance were combined to assess the health impacts of wildfire smoke in rural counties with sparse air-quality monitoring. This is the first study to demonstrate both respiratory and cardiac effects after brief exposure to peat wildfire smoke.

Cardiovascular and Cerebrovascular Emergency Department Visits Associated With Wildfire Smoke Exposure in California in 2015

“…Elsewhere, heart failure‐related ED visits were elevated in the context of peat bog fires in North Carolina in 2008, but the association was not significant when repeated for fires in 2011 and only suggestive among wildfires in 1 study from California 15, 16, 26, 43, 45. Other cardiovascular outcomes, such as cardiac dysrhythmia, or pulmonary embolism, have not been found to have a clear association with wildfire‐PM 2.5 , although some suggestive effects have been found for dysrhythmia 26, 43, 46.…”

“…In some instances, an individual county may have only 1 ground‐based air monitor for PM 2.5 . In addition, the OSHPD healthcare utilization data provided comprehensive state‐wide data of ED visits based on discharge diagnoses, whereas some other studies have relied upon syndromic surveillance 16, 26, 52. One study evaluated syndromic surveillance for cardiovascular disease in New York City and found high specificity for many of the disease entities, but often a low sensitivity and positive‐predictive value, which may underestimate the impact of wildfire smoke on cardiovascular disease 53…”

“…PM 2.5 passes deep into the lung and has been shown to increase systemic inflammation, oxidative stress, and coagulation through PM 2.5 ‐mediated changes in the autonomic nervous system 11, 14. This has been linked to cardiovascular health impacts such as ischemic heart disease and cerebrovascular events such as ischemic stroke in the ambient air pollutant PM 2.5 literature 11, 15, 16, 17, 18. Other air pollutants in wildfire smoke have also been linked to cardiovascular and respiratory outcomes in urban and ambient air pollution studies, including nitrogen oxides, carbon monoxide, and ozone 7, 8, 9, 10…”

Canadian Forest Fires and the Effects of Long-Range Transboundary Air Pollution on Hospitalizations among the Elderly

“…Each year, combustion products from local and distant wildfires impact large populations worldwide [5,[7][8][9][10][11][12][13]. The atmospheric pollutant that most consistently increases with biomass smoke from wildfires is suspended fine particulate matter (PM), which is commonly associated with increased mortality and morbidity [1,4,[14][15][16][17]. The PM in biomass smoke consists mainly of black carbon (soot and charcoal particles), organic carbon, sulfates and/or nitrates, potassium carbonate and silica [12,18].…”

Experimental drying intensifies burning and carbon losses in a northern peatland

“…O ver the past decade, peat fires have emerged as an important issue to human health, economic loss and global climate change [1][2][3] . Land use change in tropical peatlands has lowered water table position and increased fire severity, leading to carbon losses equivalent to as much as 40% of global fossil fuel combustion in some years 1 .…”