According to the California Department of Forestry and Fire Protection, the 2018 wildfires have been the most destructive in history, with close to 2 million acres of land burned. Most recently, the Camp fire (the deadliest and most destructive fire ever in California) has devastated 18,000 buildings and taken 88 lives so far. The fire was finally declared 100% contained on November 25 (meaning that authorities have built a perimeter around the entirety of the fire, not that the flames have been extinguished).
Unfortunately, the danger to human health does not end when the flames from a wildfire have been extinguished. Although the immediate risk of direct death from the fire is eliminated once the blaze is contained, the long-term health consequences of exposure to wildfire smoke can still be severe, especially as wildfires become more frequent and more severe as the Earth continues to warm.
It is common knowledge that all types of smoke are detrimental to lung health and functioning in some way. So far, studies involving animal models have confirmed significantly diminished lung functioning as a result of exposure to wildfire smoke. In one EPA study, smoke from burning pine needles caused more DNA damage in mice than burning plastic. In 2008, a group of monkeys at the California National Primate Research Center were exposed to wildfire smoke from a fire over 320 kilometers away. The infants at the time, now 10 years old, grew up to have comparatively small, stiff lungs, and weaker immune systems. Screens in the monkeys affected have shown signs of chronic lung disease. Studiesinvolving humans, in mostly overseas countries, have highlighted positive associations between exposure to wildfire smoke and heightened asthma symptoms, increased instances of chronic obstructive pulmonary diseases, and general respiratory morbidity.
However, the specific respiratory and immune effects of wildfire smoke on humans have still not yet been fully fleshed out. Assessing precise interactions between wildfire smoke and human health is difficult for many reasons. For one, studies do not usually distinguish between the sources of the pollutants that people are breathing in, so linking a health effect to its exact source is tricky. Several longitudinal studies have launched in the past few years following significant fires in the Western United States that involve tracking immune and respiratory function of populations exposed to wildfire smoke over a long period of time. For now, U.S scientists will play the waiting game.
This research could not come at a more critical time as climate modelling predictions forecast larger, longer, and more frequent wildfires as the atmosphere continues to warm and average summer temperatures rise. Although an estimated 90% of wildfires are started by humans, dry conditions can exacerbate fires, increasing the spread and increasing the likelihood of a fire starting. Warmer summer temperatures lead to higher rates of evaporation, initiating drier wildfire seasons. Recent research is also showing significant increases from prior years in the average area burnt by fires and length of fire season in the United States. As fires become more intense and more frequent in the coming years, the health risks and issues that result from them will only worsen. Research and preparation are key for the inevitable increase in patients needing care for wildfire-related health issues.