Incredible as it may seem - because the dangers of asbestos were already beginning to be known - back in the 50s the P. Lorillard Company was using deadly crocidolite fibers in its Kent cigarette filters. Since the filters on cigarettes don't provide any health benefit and act exclusively as a "marketing tool," they should be banned to cut down on harm to the environment, Thomas Novotny, a professor of public health at San Diego State University told NBC News in 2018 about the push.
Scientific publications were identified through PubMed using the following search terms: lights, ultralights, tar, cigarettes, filter ventilation, air dilution, adenocarcinoma, Ames, menthol filter rod tumorigenicity, nitrosamines, polycyclic aromatic hydrocarbons, inhalation, puff topography, mutagenicity, smoking machine, compensation, smoking behavior, and chemical yields.

Commercial cigarettes containing charcoal filters produced 40% fewer gas-phase radicals than did regular cellulose acetate filter cigarettes when smoked using the International Organization of Standardization (ISO, p = 0.07) and Canadian Intense (CI, p < 0.01) smoking protocols.
Even today, in a closely related dynamic of light” cigarettes, when Chinese smokers were asked whether their own brand of cigarettes is less harmful than others , smokers of light” cigarette brands were more likely to agree than smokers of regular” brands (32.6% to 16.1%).
So, next time you're thinking about lighting up a smoke, don't assume that you're being healthier by smoking a filtered cigarette; you're just playing into cigarette companies' hands, buying more packs to get your fix, and still threatening your long-term health.

The various pharmacologic and behavior modification techniques that are available to assist persons to stop smoking are reviewed in Chapter 46. Although controversy still exists, active cigarette smokers are reasonable candidates for pulmonary rehabilitation provided smoking cessation interventions become an important component of the process.
Filter ventilation reduces the amount of tar in the cigarette smoke when tested on smoking machines, but the increased ventilation and slower tobacco burn result in more puffs per cigarette and more toxic cancer-causing chemicals being inhaled by smokers, they write.

The assumption of greater lung exposure to tobacco toxicants leading to an increased risk for lung adenocarcinomas due to filter ventilation is may not be in conflict with clinical trials and cross-sectional biomarker studies using blood and urine biomarkers because these studies do not provide information about lung exposure, distribution, or other local effects in the lung.