Another Smokeless Tobacco Myth: The Dangerous White Patch

If you use smokeless tobacco for a long time and hold it in the same place in your mouth, the surface of your lip or cheek, called the mucosa, where the tobacco sits might thicken and turn white. A layer of white keratin is reacting to the irritating effect of the tobacco.  The reaction is similar to the development of callouses on a worker’s hand.  White patches in the mouth related to smokeless tobacco are nearly always benign.

Physicians and dentists refer to these spots as “leukoplakia” – “leuko” meaning white and “plakia” meaning plaque or patch.  Regrettably, many health professionals don’t know that smokeless use is far safer than smoking and that a wealth of research shows that smokeless tobacco-related callouses hardly ever turn into anything more serious. 

As an oral pathologist, I have decades of experience examining these patches and I have researched this issue extensively.  A 1990 study (abstract here) is typical; it showed that white patches were common in baseball players who chewed and dipped.  Upon biopsy, all were benign.  The link between white patches and cancer is virtually zero for dippers and chewers. 

On the other hand, white patches in smokers are matters of concern.  Smoke permeates the lining of the mouth, throat, airway and lungs, delivering thousands of toxic agents.  As I discussed in a 1995 journal article, studies show that white patches in smokers are much more likely to be associated with mouth cancer (abstract here).     

Too many doctors have blindly included smokeless tobacco in their anti-tobacco crusade without learning the facts. You ought to share this blog entry with your physician and dentist, and tell them that more information is available in my book (here and here).

Memo to the FDA: Please Correct Errors on Your Website

The FDA website includes several glaring errors on its Established List of Harmful and Potentially Harmful Constituents in Tobacco Products or Tobacco Smoke (here).  For example, the list wrongly identifies acrylamide as both a respiratory and a cardiovascular toxicant.  It is neither of these.  It is a probable human carcinogen, according to IARC, and it was correctly labeled in the list published in the federal register (here).  I recently collaborated with scientists from BAT to publish a comprehensive analysis of acrylamide in smokeless tobacco products from Sweden and the U.S. (here).  Our study showed that it is present in all products we tested, but “exposure… from consumption of smokeless tobacco products is small compared with exposure from food… or cigarette smoking.”

Other agents on the list are also incorrectly classified: acetone, acrolein, acrylonitrile and aflatoxin B1.  Another, acetamide, was omitted completely.

I described the problem to an FDA staffperson in late September, and she told me that a technical specialist would call back.  That did not happen, and the agency web page has not been corrected.

Government communications, including web resources, should contain accurate information.

Update, December 1, 2015: I am pleased to report that today the FDA corrected the webpage errors identified in this entry.  My compliments to agency officials.

FDA and CDC Generate Smokeless Scaremongering

While the FDA and CDC refuse to acknowledge that smokeless tobacco causes almost no disease, agency staff have produced a fresh study (abstract here) showing that smokeless tobacco users have higher trace levels of nicotine and some contaminants than do smokers.  This meaningless finding (explained below) leads to grossly misleading headlines, such as “Smokeless Tobacco More Toxic Than Cigarettes, Study Says” from Time’s Alexandra Sifferlin. (Other recent tabloidish stories from this reporter include “Flavor Science Explains How You Can Hear the Way Your Food Tastes,” “I Tried It: A 6 am No-Booze Dance Party on a Boat,” and “Healthiest Halloween Candy”).   

The media was served up a juicy quote from the FDA’s Brian Rostron, the study’s first author, in a press release (here): “exposure to nicotine and the cancer-causing tobacco constituent NNK were higher among exclusive smokeless tobacco users than exclusive cigarette smokers. This continues to put smokeless tobacco users at risk for adverse health effects, including cancer.”

First, nicotine is not a toxin, and it doesn’t cause any “adverse health effects, including cancer.”  

Second, while the study found higher levels of NNK among smokeless users than smokers, that does not support the claim that “smokeless tobacco users [are] at risk for adverse health effects, including cancer.”  Decades of epidemiologic studies involving millions of Americans show that smokeless tobacco users’ risks are infinitesimal.  British researchers estimate that U.S. smokeless-related cancer deaths are zero.

Third, from 1999 to 2012, the period of the study, trace levels of NNK dropped by two-thirds in smokeless tobacco users.

And finally, the results show that smokeless tobacco users had lower levels of mercury (in their blood) and arsenic (in their urine) than nonusers of tobacco.  In fact, smokers also had lower levels of these metals.  The study authors did not discuss the health implications of these findings.       

Public health officials should focus on meaningful research and provide appropriate scientific context for their findings, rather than scaremonger via the media and deter smokers from transitioning to markedly less harmful smoke-free products.

FDA Authorizes Eight New Snus Products

The FDA today granted Swedish Match permission to market eight new snus products in the U.S.  This is the first time that new tobacco products have received a marketing order via the agency’s premarket tobacco product review process.  Swedish Match demonstrated (here) that the products are “beneficial to the population as a whole including users and non-users...[taking] into account the increased or decreased likelihood that existing tobacco users will stop using such products, and the increased or decreased likelihood that those who do not use tobacco products will start using them.”

The products (here) consist of loose or pouch (portion) variants of Swedish Match’s General Snus:

1.  Loose

2.  Dry Mint Portion Original Mini

3.  Portion Original Large

4.  Classic Blend Portion White Large

5.  Mint Portion White Large

6.  Nordic Mint Portion White Large

7.  Portion White Large

8.  Wintergreen Portion White Large

Swedish Match filed a modified risk application for the products in June 2014, asking the FDA to change mandated warning labels (discussed here and here).  No decision has been announced.