Oral Cancer From Dip

Smokeless tobacco products have high levels of an oral carcinogen

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) Dipping or using chew may not cause lung cancer, but oral cancer is still a big risk. Smokeless tobacco products have nitrosamines, which can cause cancer at high levels.

A recent study tested a concentrated substance found in smokeless tobacco on rats. Results found that after 17 months, 20 rats had 91 oral tumors.

"Smokeless tobacco can cause cancer too."

Stephen Hecht, PhD, research professor at the Masonic Cancer Center at the University of Minnesota, led an investigation into smokeless tobacco.

For the study, 20 rats were given 15 parts per million (ppm) of (S)-NNN in their drinking water for 17 months. (S)-NNN is a nitrosamine (NNN), one of the suspected carcinogens in smokeless tobacco.

The dosage of (S)-NNN given to the rats was equal to a human consuming half a tin of smokeless tobacco known as ‘dip’ or ‘chew’ over the course of 30 years.

Every single one of the rats in the experiment developed multiple oral cavity tumors for a total of 91 oral tumors.

Dr. Hecht said, “This is the first example of a strong oral cavity carcinogen that’s in smokeless tobacco.”

“Our results are very important in regard to the growing use of smokeless tobacco in the world, especially among younger people who think it is a safer form of tobacco than cigarettes. We now have the identity of the only known strong oral carcinogen in these products.”

“The most popular brands of smokeless tobacco that are sold in the U.S. have unacceptable high levels of this particular carcinogen. And smokeless tobacco is a know cause of oral cancer.”

“Obviously, we need to decrease the levels of this material in all smokeless tobacco products—or eliminate it altogether.”

NNNs naturally occur in some foods at very low levels. Dr. Hecht recommended that the U.S. Food and Drug Administration regulate (S)-NNN to be at much lower levels in smokeless tobacco like those in the food supply.

This study will be presented at the 244th National Meeting & Exposition of the American Chemical Society from August 19-23, 2012 held in Philadelphia, PA.

Funding for this study was provided by the National Cancer Institute, no conflicts of interest were found.

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Review Date: 
August 15, 2012
Last Updated:
August 22, 2012