Human Journey

Car Exhaust Linked to Thickening Arteries

An international team of researchers based at the University of California at Berkeley have linked exposure to car exhaust with thickening arteries, adding a new item to the list of health problems caused by car pollution.

The study involved almost 1,500 people near Los Angeles, which has a reputation for some of the worst smog and air quality in the country. The researchers measured the thickness of the carotid artery by ultrasound and saw that for people that live within 328 feet (100 meters) of a freeway, their arteries thickened more than twice as fast as the other participants in the study.

Thickening of arteries is linked to increased risk of high blood pressure, heart attack, and stroke.

“For the first time, we have shown that air pollution contributes to the early formation of heart disease, known as atherosclerosis, which is connected to nearly half the deaths in Western societies and to a growing proportion of deaths in the rapidly industrializing nations of Asia and Latin America,” said Michael Jerrett, a co-author of the study, in a statement.

The researchers say more research is needed to see how exposure to car exhaust affects sub-groups of people, such as those with high cholesterol or with low incomes. More studies are underway at the University of Southern California and in Basel, Switzerland and Girona, Spain.

Related Links:

Study Published in PLoS ONE

English version of Swiss Press Release

–James Robertson


Tasha Eichenseher is the Environment Producer and Editor for National Geographic Digital Media. She has covered water issues for a wide range of media outlets, including E/The Environment Magazine, Environmental Science & Technology online news, Greenwire, Green Guide, and National Geographic News.

About the Blog

Researchers, conservationists, and others share stories, insights and ideas about Our Changing Planet, Wildlife & Wild Spaces, and The Human Journey. More than 50,000 comments have been added to 10,000 posts. Explore the list alongside to dive deeper into some of the most popular categories of the National Geographic Society’s conversation platform Voices.

Opinions are those of the blogger and/or the blogger’s organization, and not necessarily those of the National Geographic Society. Posters of blogs and comments are required to observe National Geographic’s community rules and other terms of service.

Voices director: David Braun (

Social Media