The Three Smokes in Global Mortality

Airborne toxins cause 14 million premature deaths worldwide according to the World Health Organization. Most of these toxins arise from fossil fuels, cigarettes, and inefficient home fires that I designate as “ the three smokes .” Their microscopic particles share toxic properties that exacerbate oxidative stress and inflammation and accelerate many aging processes. Dust from the earth's crust can also be toxic. Air pollution particles are characterized by size, with standards set for particles smaller than 2.5 μm (PM2.5). The particles and gases that comprise air pollution are also included in the exposome, a global environmental assemblage of toxin exposure, starting at conception and extending across the life span. Some individuals or groups may be resistant to airborne toxins, as shown for elderly surviving cigarette smokers. The growing exposure to toxins from fossil fuels and tobacco since 1800 was concurrent with longevity increases. In essence, we have swapped mortality caused by infections for accelerated aging from fossil fuels and cigarettes. The toxic mechanisms in airborne particles are considered in the next chapters.