By Miriam Falco

CNN Medical Managing Editor

Smokers of U.S. brand cigarettes may get more bang for their buck in the worst way according to a small study conducted by the Centers for Disease Control and Prevention.

Researchers found U.S. made cigarettes contain more cancer-causing chemicals than some cigarettes brands made elsewhere around the world.

“Not all cigarettes are made alike” says Dr. Jim Pirkle, deputy director for science at the CDC’s National Center for Environmental Health. He says this is the first study to show that “U.S. cigarettes have more of the major carcinogen [TSNAs] than foreign made cigarettes." TSNAs are “tobacco-specific nitrosamines,” the major cancer-causing substance in tobacco.

126 smokers in five cities – Waterloo, Ontario; Melbourne, Victoria (Australia); London, England, Buffalo, New York, and Minneapolis, Minnesota – were recruited for this study.

They were between the ages of 18 and 55 and smoked at least 10 cigarettes a day for the past year and had been brand loyal for at least three months. The cigarettes smoked by the study recruits represented some of the more popular brands for each country including: Players light and DuMaurier in Canada; Marlboro, Newport Light, Camel Light in the U.S.; Peter Jackson and Peter Stuyvesant in Australia; and Benson & Hedges and Silk Cut Purple in the United Kingdom.

Scientists analyzed more than 2,000 cigarette butts to get the data they are reporting today, says Pirkle.

When researchers compared cigarette brands in the U.S. to those in Canada and Australia, they found three times higher levels of the cancer causing substance in the U.S. smokers’ mouths. The mouth levels are important because they give an indication of what levels if carcinogens are going into the lungs. (Smoking tobacco is a major cause of lung cancer).

“If you want to stop exposure to these things, you have to stop smoking.”

They also found twice as much TSNA in the urine samples of U.S. smokers compared to those in Canada and Australia, an indication that cancer-causing substance has traveled throughout the body.

There is no one group that speaks for the tobacco institute anymore, according to Darryl Jason, a spokesman for the Tobacco Merchants Association (TMA), which is why he couldn’t comment on the study. The TMA was founded in 1915 to “manage information of vital interest to the worldwide tobacco industry according to their website. Jason did point out that cigarettes manufactured in the U.S. contain a different blend of tobacco from cigarettes made elsewhere.

The study acknowledges that there are different types of tobacco depending where the cigarettes are made. But that’s only one factor says Pirkle: “The TSNA levels largely come from the way tobacco is cured.” The heating process, humidity and the type of the ferlizer used to grow the tobacco also contribute to the levels of cancer causing substances, says Pirkle.

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