Smog hangs over the city of Santiago, Chile. Credit: Anne Crecelius

Upon arriving in Santiago, Chile, my travel companions from the University of Dayton and I were struck by the beautiful sights of the Andes mountains and the not-so-beautiful sight of a cloud of smog hanging over the city.

Like many major metropolitan areas, such as Los Angeles or Mexico City, the city of Santiago (population ~8 million) suffers from poor air quality. Typical contributors to pollution, such as dust and automobiles, are part of the problem, but Santiago also has a geological disadvantage. The city is located in a valley between the beautiful Andes mountains and the Pacific Coast, which often causes polluted air to “settle” in the city. Frequent thermal inversions—where cold air settles beneath warm air—amplify the smog problem, especially in the winter months (June through August in the Southern Hemisphere).

A recent study linked millions of deaths to air pollution in Asian countries. But what makes air pollution so bad for our bodies? Different pollutants can have different effects on each of the body’s systems. Depending on the size and amount of pollutants in the air, particles can irritate our lungs or even enter our bloodstream. Once in the blood, toxins can negatively affect multiple organs such as the lungs, heart, brain and liver.

So what are the residents of Santiago, or visitors like me, to do?

Keep Preexisting Conditions in Mind

People with existing conditions that affect the ability to breathe are at increased risk of problems caused by high smog levels. For example, my colleague who has asthma had to be extra careful and used her albuterol inhaler frequently. Albuterol is a medicine that acts on the passageways of the lungs to help them open and allow air to flow more easily.

Exercise with Caution

If air quality is exceptionally poor, such as during a thermal inversion, take extra caution when exercising outside, or consider indoor options.

Share the Road

Using public transportation, biking and walking can help reduce vehicle emissions. If you are around high-traffic areas, you still may want to cover your face to protect yourself from the larger particles in the air. While walking around the city, I observed many Chileans using this method.

My colleagues may not have taken notice, but I thought “I spy physiology!”

This post is part one of a three-part series by physiologist Anne Crecelius, PhD, chronicling her summer of research and travels through South America. Crecelius is assistant professor at the University of Dayton.