Study: Light cigarettes spark rise in most common type of lung cancer

COLUMBUS, Ohio — Lung cancer rates in the United States have dropped continuously since peaking in the early 90s, yet the most common form of the disease has actually increased steadily for decades — and scientists believe light cigarettes are a primary reason why.

Researchers at Ohio State University’s Comprehensive Cancer Center wanted to find out the reason behind the consistent increase in cases of adenocarcinoma — the most common type of lung cancer — over the last 50 years. Adenocarcinomas make up about 40 percent of lung cancer cases, according to the American Cancer Society, and while it’s typically seen in current or former smokers, it’s also the most common form of lung cancer in non-smokers.

With more states tightening their public smoking laws, more smokers are quitting and, consequently, other types of lung cancers have shown a drop in numbers. But not adenocarcinoma. The researchers point to the design of light cigarettes as a main factor. The filter on light cigarettes have been touted by manufacturers as a “healthier” choice, but their findings prove quite the opposite

Utilizing readings that included toxicology and chemistry studies, along with human clinical trials and peer-reviewed studies that focused on both smoking behavior and cancer risk, and internal tobacco company documents, researchers discovered that ventilation holes found in the filters of light cigarettes allowed the cigarette it to burn more slowly. The design allows more toxic chemicals to make their way to the lungs because smokers are taking longer drags.

“The filter ventilation holes change how the tobacco is burned, producing more carcinogens, which then also allows the smoke to reach the deeper parts of the lung where adenocarcinomas more frequently occur,” says Dr. Peter Shields, deputy director of the center and a lung medical oncologist, in a release.

Shields says that filters were really created to “fool smokers and the public health community” that they made cigarettes safer to smoke and presented consumers with fewer health risks.

“The public health community thought that those holes might a good thing originally. Unfortunately, it’s becoming clear there are some consequences with the design that make cigarettes more dangerous and cause people to die in increasing numbers,” he explains in a university handout.

Though tobacco companies were banned in 2009 from labeling products as “low tar,” “mild” or “light,” the study authors believe the latest research should be grounds for the Food and Drug Administration to put similar restrictions on ventilation holes in filters. They believe such a move would lead to fewer lung cancer cases and deaths.

“The FDA has a public health obligation to take immediate regulatory action to eliminate the use of ventilation holes on cigarettes,” says Shields. “It is a somewhat complicated process to enact such regulations, but there is more than enough data to start the process. We believe that such an action would drive down the use and toxicity of conventional cigarettes, and drive smokers to either quit or use less harmful products.”