Smoking Causes Immediate Damage
Effects of Cigarette Smoke Cause Genetic Damage in Minutes
By Jennifer Warner
WebMD Health News
Reviewed by Laura J. Martin, MD
hand holding cigarette next to DNA strand

Jan. 18, 2011 -- The negative health effects of smoking may begin within minutes, not months of cigarette use.

A new study shows that genetic damage associated with lung and other types of cancer associated with smoking became apparent within 15-30 minutes of inhaling cigarette smoke.

Researchers say it’s the first study to document how quickly certain toxic chemicals in cigarette smoke known as polycyclic aromatic hydrocarbons or PAH can cause DNA damage linked with cancer in humans.

“The results clearly demonstrate immediate negative health consequences of smoking, which should serve as a major warning to anyone contemplating initiating tobacco use,” researcher Yan Zhong, of the Masonic Cancer Center and University of Minnesota and colleagues write in Chemical Research in Toxicology.

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Smoking Does DNA Damage

Researchers say smoking is to blame for about 90% of lung cancers and is linked to at least 18 other types of cancer.

Previous research has suggested that PAHs are one of the major contributors to these unhealthy effects of smoking, but until now little was known about the specific mechanism concerning how these chemicals in cigarette smoke cause DNA damage in humans.

In the study, researchers added an easily identifiable form of PAH to cigarettes and then tracked how it was metabolized in 12 volunteers who smoked the cigarettes.

The results showed that within 15-30 minutes after the volunteers smoked the cigarettes, the PAH quickly formed a toxic substance in the blood that is known to damage DNA and cause genetic mutations that lead to cancer.

"These results provide the first direct evidence for human metabolic activation of a PAH delivered in cigarette smoke and indicate the potential for immediate genetic damage in a cigarette smoker," write the researchers.