The Dangerous Particulate Matter in Brushfires

Whether it's drought or carelessness that causes brushfires, the result is the same; loss of wildlife habitat, smoke and sometimes, damage to buildings or even loss of human life. However, brushfires aren't always a terrible event. There are some plants that require the heat of a fire before their seeds can germinate, therefore, suppressing fires all the time might just prevent these plants from growing. Some examples of these fire dependent plants are:

Lupines (Lupinus spp): they will do much better after a fire because of the additional nitrogen in the soil.
Lodgepole pine (Pinus contorta): they need the heat from a fire to open their cones so their seeds can disperse.
Snowbrush (Ceanothus velutinus): needs the extreme heat of a fire to germinate their seeds.
Deerbrush (Ceanothus integerrimu), blueberry (Vaccinium spp), ricegrass (Achnatherum hymenoides): require fires to add nutrients in the soil and help germinate seeds.

So wildfires can be good. But they are also a danger to wildlife and people for obvious reasons. Many animals, if they manage to escape and survive suddenly find themselves displaced, and if the fire moves into habituated areas, it can burn down houses and outbuildings. While these are obvious, something a bit less obvious is the damage brushfires can do to the lungs. Many agencies issue warnings for people, especially the elderly and the young, to stay indoors and limit outdoor activities.

The worst particulate matter are those particles that are small ones. These are the particles up to 2.5 micrometers in size. The very small particles aren't even usually visible to people and because of their diminutive size, they can float on the air currents for a long time, sometimes traveling for hundreds of miles. Larger particles are able to stay airborne for minutes or hours, but the smaller ones can drift around for days or even weeks. What this means to humans is that people can be breathing them in without realizing it, even days or weeks after a fire. A person might not even be aware that there is a fire hundreds of miles away, yet the small particulate matter has drifted to where they are. Small particles can easily get into the lungs and can contain toxins from the environment.

Once the small particles are inhaled, the body will have a reaction and try to eliminate the particles from the lungs. This includes the tiny cilia moving around to try to move the particles out of the lungs. This is what causes coughing and wheezing. If a person has asthma, it will be aggravated by inhaling these tiny particles. If there are toxins or carcinogens in the smoke, permanent lung damage can occur, including cancer. For these reasons, people should stay up to date on the news, especially in drought conditions. If there are brush fires in the area, everyone should be mindful and reduce their outdoor activities.