The fire is domesticated. The smoke is not. Why?

Estimated reading time: 4 minutes

Man has tamed fire. What about smoke? Still little known, despite its far from beneficial effects on the environment and the health of living beings. Researchers continue to search for answers about smoke. Read more.

After all, what is smoke?

Smoke is a collection of solid and gaseous particles emitted after the combustion of a material released by any type of fire (forest, brush, crop, structure, tires, waste, or wood burning) or after a natural event such as a volcano.

The smoke is composed of:

  • carbon

  • hydrogen

  • oxygen

  • nitrogen

  • sulfur dioxide

  • other chemicals, including aldehydes, acid gases, polycyclic aromatic hydrocarbons (PAHs), benzene, toluene, styrene, metals, and dioxins. 

The effects of smoke on human health and the environment

On human health, smoke can have devastating effects if exposure lasts too long, such as respiratory problems.

Due to prolonged aspiration, smoke also increases the risk of heart disease and lung cancer. The most immediate symptoms are burning eyes and a runny nose. In short, effects can emerge in the medium and long terms.

Depending on the wind direction, the smoke affects the air quality in the areas near the fire, whether urban or rural.

Forest wildfires

According to Wayne Cascio, a cardiologist, and director of the Center for Public Health and Environmental Assessment "Despite carrying high amounts of carbon monoxide and volatile chemicals, as trees, shrubs, grass, and other vegetation are engulfed by the fires, large amounts of smoke, soot, and other pollutants are released into the air. In larger fires, the smoke can rise many kilometers into the stratosphere and spread over entire regions, causing air pollution in areas far from where the flames actually were.”

Birds and plants also suffer the consequences of smoke

The birds when exposed to smoke can have their activity affected, such as their singing, for example. The plants can have their photosynthesis process affected because of the prolonged darkness caused by thick smoke. 

Forest wildfires, therefore, are responsible for destroying natural habitats and altering the local ecosystem. In fact, little is known about the actual extent of the damage caused by smoke exposure during and after fires.

The verdict remains open.

"We are trying to understand the lifetime of smoke in the atmosphere and how it evolves chemically," stated one researcher about the effects of smoke. “However, characterizing the impacts that the smoke will have on the environment is still a challenge. What is assumed is that, over time, the smoke becomes more toxic and its effect hastens local and more distant climate changes. It remains to be seen whether the smoke residue can be converted into nutrients for the soil. Many questions and few answers," he added.

Smoke becomes even more toxic after some time in the air

The longer the smoke is in the air, the more dangerous the situation of the person inhaling it becomes. After one day in suspension, the smoke becomes four times more toxic.

The reaction turns out to be a conversion of the compounds in the smoke particles into highly reactive compounds. When inhaled, these reactive compounds, known as free radicals, can damage the body's cells and tissues.

The damage may take place even if you are far away from a fire if smoke is being blown in your direction. Inhaling the smoke then will increase the propensity for infections, allergies, and the risk of getting cancer, because the smoke particles may contain polyaromatic hydrocarbons that when oxidized become carcinogens.

Scientists and researchers still have a lot to learn about smoke!

All researchers including scientists and ambientalists have not yet been able to pinpoint exactly the source of the smoke. That is, whether it comes from natural sources or not:

  • of dust blown into the air

  • of the salt lifted from the oceans by the wind

  • from urban or rural fires

  • from vehicles, airplanes, or ships

  • from industry

  • from other human activities

"Improving the accuracy of how these particles are measured and identified could not only help authorities better monitor air pollution but also potentially help identify critical individual sources of particles and propose appropriate countermeasures to improve air quality," states Dr. Burkhard Beckhoff, a researcher at Germany's Physikalisch-Technische Bundesanstalt in Berlin.

For these and other reasons, a trio of researchers at Cambridge University in the UK wants to abolish all existing scientific literature on smoke and start the research again. "It was only in the last decade that some experimental and computational techniques in combustion science were able to peek behind the door to reveal insights into the early mechanisms of carbon particle formation in flames,".


Even though we have tamed fire, controlling and understanding smoke remains a challenge so far. Understanding it means obtaining mechanisms that can avoid the consequences of wildfires (which are already disastrous) and other emissions from different sources.

The release of carbon nanoparticles into the atmosphere needs to be a priority for the scientific communities because it affects living beings and the environment as well. If stopping the smoke is impossible, remedying its effects is fundamental to the survival of the planet’s sustainability.

By Marco Veado - THINK GREEN