LOS ANGELES — Cigarette-smoking Americans receive higher doses of the most potent carcinogens than do smokers in many foreign countries because of variations in the way tobacco is processed for cigarettes, researchers from the Centers for Disease Control and Prevention reported this week.
American cigarettes are typically made from “American blend” tobacco — a specific blend that, because of growing and curing practices, contains higher levels of cancer-causing tobacco-specific nitrosamines. The most popular Canadian, Australian and British brands, in contrast, are made from “bright” tobacco, which is lighter in color and cured differently.
The study was designed primarily to correlate how well levels of the chemicals in cigarettes correlate with levels of their metabolites in smokers’ urine. The data about exposure to the chemicals in different countries were an added benefit.
Changes in curing and blending practices could reduce U.S. smokers’ exposure to this particular carcinogen, said Dr. Jim Pirkle of CDC’s National Center for Environmental Health, but that would not necessarily result in a safer product.
