Wild Fires and their Health Effects
(Originally published in the Townsend Letter Dec 2020)
Introduction
Every year the number of wild fires burning across the U.S. increases as does the proximity to major cities and towns. Some wild fires are man-made, both accidental and on purpose, and others are due to forces of nature like a lightning strike. Global warming and climate change also play a role on the increase in wildfires. Numerous toxic chemicals are released into the air when fires rage through forests, fields and towns. The health effects of the first responders is well documented but not as much attention is payed to the effect on those living or working nearby. It’s important for physicians and health care providers to understand what chemicals are released when a wild fire burns. These toxicants can travel through the air contributing to respiratory conditions in vulnerable populations. Identifying the health effects of wild fires and how to treat these patients is imperative as wild fires are expected to increase each year.
As the world warms up it has the potential to burn
While wildfires are a normal part of our landscape, across the U.S. and the globe the number of fires each season is increasing and wildfire seasons are longer each year. Climate change is considered a driving force behind the increase. According to the National Interagency Fire Center, from January 1, 2020 to August 10, 2020 there were 33,917 wildfires in the U.S. compared with 28,821 wildfires in the same period in 2019. About 2.3 million acres have burned in the 2020 so far, compared with 3.6 million acres in 2019. California has been especially hit hard in 2020 seeing a 68% increase in wildfires from Jan 1, 2020 to August 20, 2020 compared to the same period in 2019. California is an easy example of climate change with warmer temperature and precipitation. Climate change raises the risk of wildfires several ways; longer periods of draught, warmer temperatures, less rain or snow pack, and drying out vegetation. 1 Warmer temperature cause the atmosphere to create more thunderstorms and lightning strikes which contribute to more wildfires. Man-made fires, whether on purpose or accidental, will easily spread in such warm and dry conditions. 1
What’s burning?
Wild fires can rip through forests, grass lands, buildings and homes that stands in its path. Numerous toxicants are released into the air that are known carcinogens, immunotoxins, endocrine disrupting compounds and can affect the pulmonary and cardiovascular system. Both firefighters and residents near fires are exposed to these chemicals. Toxicants travel through the air to neighboring town, cities and even other states. A 2004 publication in the Journal of occupational and Environmental hygiene identified some of these harmful chemicals. They include; acrolein, anthracene, benzene, benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, carbon monoxide (CO), chrysene fluoranthene, formaldehyde, indeno(1,2,3-cd)pyrene, particulate matter—fine particles smaller than 10 µm,) phenanthrene, and pyrene. 2 Most of these are know to disrupt the endocrine, neurological, immune and cardiopulmonary system. Even in healthy individuals without underlying conditions. 3
In 2013 the U.S. department of Agriculture released a report outlined additional harmful chemicals emitted from wildfires and forest fires including; carbon monoxide, aldehydes, particulate matter, crystalline silica, and polycyclic aromatic hydrocarbons. Again, many of these are known carcinogen and respiratory irritants. 3 When vegetation burns it emits carbon monoxide, sulphur dioxide, particulate matter, aldehydes, benzene, and acrolin. 3 It will emit pesticides or herbicides if the area has been sprayed such as agriculture or farmland.
As fires move toward urban areas and homes, buildings and structures are burned and the contents inside them. Additional chemicals are released such as; pesticides, arsenic, lead, mercury, solvents, paints, cleaning solutions, plastics and their chemical compounds, perflourinated chemicals, volatile organic compounds and more. 4 The adverse health effects spans multiple organ systems. As firefighters move in to extinguish the flames, chemical suppressants and foams are used and have a host of health effects as well. 5 The make-up of these wildfire suppression chemicals allows firefighters to contain the fire while also protecting physical structures and homes. There are two major types of wildfire suppression chemicals: foams and flame retardants and this is often what the average person sees on the evening news being prayed from planes flying over a wildfire. These can also have detrimental health effects especially to firefighters who are in close contact with these chemical suppressants. 5 These foams and flame retardants can also travel in the air effecting people nearby.
Health effects
As wildfires are becoming more prevalent near towns and cities, emitting harmful chemicals into the air, health care providers need to consider the health impact on those living nearby. Certain populations are more vulnerable to chemicals released from wildfires. These populations include children, the elderly, and pregnant woman.6,7,8 People with underlying conditions are predisposed to the effects of toxicants from wild fires and those conditions include; asthma, COPD, diabetes, cardiovascular diseases and cystic fibrosis. 6,7,8 Even people who are younger and without any underlying conditions may experience symptoms related to wildfires. Short term effects range from shortness of breath, wheezing, coughing, sore eyes and throats, runny nose, and sinus issues, to headaches, fatigue, heart palpitations, and chest pain. Longer term effects include increases in asthma-related hospitalizations, chronic and acute respiratory and cardiovascular health outcomes, and even premature death. 9,10 People with these health effects should seek medical attention, especially asthmatic patients, as the use of a steroid inhaler, home oxygen and other medication may be needed in the short term.
As fires burn nearby and flame retardants are sprayed from above, it is important people take measures to protect themselves from the exposures to toxicants released in the air.
Recommendations include;
Stay indoors with the windows closed
Use a HEPA-type air filter in the home and at work
Wear an N-95 mask indoors and outdoors
Roll up your car window when driving
Seek out a health care provider trained in environmental medicine to help mitigate the effects of toxicant exposure.
If someone is experiencing acute cardiac or pulmonary concerns immediate medical attention may be required at an emergency room or urgent care center. Advanced pulmonary function testing and cardiac tests will help evaluate if there is long term damage to the lungs or heart. Once acute concerns are addressed and they are stable then seeking out the guidance from an environmental medicine doctor to address the toxicant exposure from wildfires will help over health. Most people exposed to chemicals emitted from wildfires experience only mild symptoms such as ear, nose and throat irritation, coughing, shortness of breath or wheezing. But over time these toxicants can produce chronic health issues.
Mitigate the health effects of wildfires
Many of the chemicals inhaled during a wildfire can directly damage lung tissue, cause inflammation in respiratory passageways, create oxidative stress and free radicals, cause macrophage cytotoxicity, and deplete glutathione; which is the most important antioxidant in the body.11 These mechanisms of damage underlie the changes in respiratory symptoms and why people seek out healthcare after a wildfire event. To mitigate some of the effects restoring glutathione levels, offsetting free radical production with antioxidants, and trying to decrease body burden of toxicant exposure are key methods in treating or preventing health effects from wildfire smoke. Most of the research done in this area is on people living in areas of high air pollution and on firefighters who as frontline workers face the highest level of exposure and health effects from wild fires.
Air pollution contains chemicals found in wildfire smoke, including particulate matter, carbon monoxide and sulfur dioxide and benzene. Carotenoids, vitamin-D and vitamin-E help protect against pollution damage which can trigger asthma and COPD. 12 Vitamin-C, curcumin, and omega-3 fatty acids also help mitigate the harmful effects.12 N-acetylcysteine, is a major antioxidant in the body and precursor to glutathione. NAC has long been used for supporting lung function in conditions such as COPD and chronic bronchitis. Studies show it is beneficial in patients with inhalational smoke-induced lung injury.13 Glutathione is beneficial for patients with asthma, COPD and bronchitis. Supplementation can help mitigate the effects on the lung of inhaled smoke.14
Sauna therapy has been used for years for numerous cardiovascular and pulmonary conditions. Mayo clinic preceding publish an excellent review showing sauna bathing can reduce the risk of high blood pressure, cardiovascular disease, and neurocognitive diseases and pulmonary diseases. 15 Sauna is being utilized by firefighters as a method to treat the damage induced by wild fire smoke. A study just completed by researchers at the University of Arizona demonstrated sauna therapy lowered the urinary level of polyaromatic hydrocarbons PAHs of firefighters. 16
Sauna therapy, vitamins, minerals and anti-oxidants are not only important for lung function and pulmonary conditions but also to support liver metabolism of toxicants. As stated above, wildfire smoke emits numerous chemicals into the air including lead, mercury, arsenic, pesticides, solvents and polyaromatic hydrocarbons. An environmental medicine approach can be useful in assessing and addressing health concerns due to wildfire smoke. An in-depth history and intake, testing for toxicants, and treatments including sauna therapy, vitamins and minerals are an important step in mitigating effects from wildfires.
Summary
The past few years have shown and increase in wildfires across the U.S. and around the world. This is in-part due to global warming and changes in our climate. Even man-made fires, both on purpose or accidently, are spreading like never before due to warmer, drier conditions. As vegetation, forests, structures and homes burn numerous toxicants are release posing health risk for both firefighters and those living and working nearby. It is important health care providers understand the toxicants emitted from wildfires and the flame retardants used to manage fires, and their effects on health. Educating patients on measures to protect themselves during the fire and providing treatments for managing the health effects are a key part of integrated care.
References
1. Jolly, W., et al. Climate-induced variations in global wildfire danger from 1979 to 2013. Nat Commun 2015;6,7537. https://doi.org/10.1038/ncomms8537
2. Booze TF, et al. A Screening-Level Assessment of the Health Risks of Chronic Smoke Exposure for Wildland Firefighters. Journal of Occupational and Environmental Hygiene. 2004;1: 296–305.
3. United States Department of Agriculture. Wetland firefighter smoke exposure. Published Oct 2013. https://www.fs.fed.us/t-d/pubs/pdfpubs/pdf13511803/pdf13511803dpi100.pdf Accessed Aug 10 2020.
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13. Ashraf U, et al. Nebulized heparin and N-acetylcysteine for smoke inhalational injury: A case report. Medicine (Baltimore). 2018;97(19).
14. Rahman I, MacNee W. Lung glutathione and oxidative stress: implications in cigarette smoke-induced airway disease. Am J Physiol. 1999;277(6):L1067-L1088.
15. Laukkanen JA, Laukkanen T, Kunutsor SK. Cardiovascular and Other Health Benefits of Sauna Bathing: A Review of the Evidence. Mayo Clin Proc. 2018;93(8):1111-1121
16. Burgess, J. L., et al. Evaluation of Interventions to Reduce Firefighter Exposures. Journal of occupational and environmental medicine. 2020;62(4), 279-288.