What type of particles from combustion can cause health problems?

Particulate matter is a significant concern when it comes to combustion processes because it consists of tiny solid or liquid particles that can be inhaled and cause various health issues. These particles are categorized based on their size, with PM2.5 and PM10 being the most commonly referenced. PM2.5, for instance, can penetrate deep into the lungs and even enter the bloodstream, leading to respiratory problems, cardiovascular diseases, and other serious health effects.

While carbon dioxide, nitrogen oxides, and hydrocarbons are associated with combustion and can have harmful environmental effects, they have a different pathway of impact. Carbon dioxide contributes to climate change, nitrogen oxides are involved in creating smog and ground-level ozone, and hydrocarbons can contribute to the formation of ground-level ozone as well. However, none of these directly cause health issues in the same way that particulate matter does when inhaled.