Photograph by Carsten Peter
A climber in Russia's Kamchatka Peninsula wears a gas mask to keep noxious volcanic fumes out of his lungs. The vital organs filter air 24 hours a day, providing the body with the oxygen it needs to survive.
Photograph by Martin Dohrn/Royal College of Surgeons/Science Photo Library
Bronchi fan out like coral in this resin cast that also shows pulmonary arteries and trachea. The bronchi supply air and pulmonary arteries supply blood to the lungs. Together they take in air from the atmosphere, oxygenate the blood, and excrete the carbon dioxide back out of the body.
Photograph by Karen Kasmauski
A Richmond, Virginia, teenager wears a CPAP (Continuous Positive Airway Pressure) machine to treat sleep apnea, a condition in which air passage to the lungs is obstructed during sleep. The CPAP pumps air in a continuous stream, easing breathing.
Air Pollution Victim
Photograph by Bob Sacha
A Hebei, China, resident says his neck lesions are the result of a toxic environment. It's a likely story—barely a third of China's cities have air that meets national air-quality levels, which are below World Health Organization levels. Indoor air pollution from coal burning takes more than 700,000 lives a year, and respiratory diseases cause nearly a quarter of all deaths in the countryside.
Photograph by Chris Johns
Backlit by midnight flames, firefighter Kim McKillop shows the strain of battle in Oregon's Deschutes National Forest. Inhaling smoke on the fire line is part of the job, but researchers are now looking closer at the effects of wildfire smoke. When a forest goes ablaze, it discharges hundreds of chemical compounds, including carbon monoxide. Over time the wear and tear on the human lungs constitutes a serious health risk.
Photograph by Justin Guariglia
Speeding through Dacca, Bangladesh, on foot should keep this rickshaw driver's lungs in top shape, but pollution is a heavy counterweight. Surgical masks like these are now commonplace in Asia, where environmental laws are often lax if they exist at all. Dacca's air is burdened by vehicle emissions; air quality improved after the advent of unleaded gasoline, but toxins such as carbon monoxide persist.
Photograph by James L. Stanfield
Miners work by candlelight in a Sri Lankan gem mine. Mines are notorious for dust and toxic gases such as carbon monoxide and radon, which can enter the body via the lungs.
Photograph by Michael Nichols
Workers at the National Research Institute of Sports Science in Beijing, China, test a long-distance cyclist's blood-oxygen content. The lungs' capacity to deliver oxygen to blood, where it is consumed by muscles, is a major factor in an endurance athlete's ability to perform.
Photograph by Paul Nicklen
A diver makes a slow decent into a vortex of 50,000 farmed salmon in British Columbia, Canada. As scuba divers sink deeper underwater, the weight of the water above them creates pressure. As the diver resurfaces, his body decompresses, and extra nitrogen escapes into the bloodstream, where it is carried to the lungs for excretion. If a diver surfaces too fast, bubbles can form in the blood and tissues, causing the bends.
Photograph by Nick Caloyianis
A Fort Lauderdale swimmer releases the air in his lungs underwater. Most people panic after a little more than a minute without air, but free divers—divers who don't use oxygen—can hold their breath for much longer. The body stores pockets of oxygen for moments such as these, and the brain shuts down other systems of the body before allowing itself to black out.
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National Geographic Magazine
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