You think it can bring health, but it is actually harmful - let's talk about filters

This is the 4279th article of Da Yi Xiao Hu

Today, I'm going to talk to my friends about cigarette holders. Speaking of cigarette holders, they are commonly known as filter holders. It is a small filter rod located at the mouth of the cigarette. As early as the 1920s, some tobacco companies invented such a filter rod in order to reduce the discomfort of the tobacco leaves directly contacting the lips. At the same time, it can filter out some tar and smoke, which seems to be healthier. The earliest filter rod was made of paper, and later there were filter holders made of cotton, asbestos and other materials. However, there are relatively few applications. It was not until the 1950s that filter cigarettes began to be widely used with the development of acetate fiber. The materials currently used in the manufacture of cigarette filter holders include: diacetate fiber tow, activated carbon, polypropylene tow, inorganic mineral fiber, etc. In the past 30 years, the emergence of some new technologies has changed the shape of the filter, such as laser drilling on the filter, so that part of the air can be inhaled when smoking, thereby reducing the concentration of the cigarette smoke. There are also some mint-flavored substances added to the filter to reduce the irritation of the smoke. Judging from the publicity of various tobacco companies, this kind of filter can filter out some harmful substances in cigarettes, such as tar and particulate matter. It seems to be a measure that can reduce the harm of cigarettes to the human body. But is this really the case in practice?

Studies have long found that when smokers inhale cigarette smoke, they inhale particles and fragments of the filter material into their lungs. For example, tiny fragments of acetate fiber are inhaled into the lungs. This is especially true for some inferior filter materials. Over time, it is inevitable that harm will occur to the human body.

In order to meet the smoke concentration standard, various cigarette companies use laser technology to punch holes in the filter tip. When the cigarette with laser punched filter tip is smoked on a special machine for testing cigarettes, the smoke concentration does decrease, because the laser hole on the filter tip can leak some air, thereby reducing the smoke concentration of the cigarette. However, in reality, for this kind of cigarette with laser punched filter tip, some old smokers feel that the smoke concentration is small and not addictive, so they will use their fingers to block these small holes on the filter tip to increase the smoke concentration. Another part of the smoke feels that the smoke concentration is light, which reduces the irritation to the throat, but prompts smokers to inhale more smoke. At the same time, because the concentration is lighter, smokers may smoke deeper and smoke is more likely to enter the periphery of the lungs. With the widespread use of filter tips, the burning speed of cigarettes has also slowed down, which will produce more harmful substances and give smokers more time to smoke. In the same way, the mint-like substances in the filter rod reduce the irritation of cigarette smoke to the throat, thereby prompting smokers to inhale more smoke.

When filters first appeared, some people believed that this measure could reduce the damage of cigarette smoke to the lungs and reduce the occurrence of tumors. However, in the past 30 years, it has been found that this is not the case. For example, a review article published in the Journal of the National Cancer Institute in 2017 comprehensively elaborated on this issue. The emergence of filters is related to changes in the spectrum of lung cancer diseases. In the past 30 years, the spectrum of lung cancer diseases has changed from mainly squamous cell carcinoma to mainly adenocarcinoma. Squamous cell carcinoma generally occurs in the central airways, while adenocarcinoma occurs in the periphery of the lungs. Studies have shown that the direct stimulation of cigarette smoke will increase the probability of squamous cell carcinoma in the central airways. Cigarettes with added filters will make it easier for the smoke inhaled by smokers to enter the periphery of the lungs, leading to the occurrence of lung adenocarcinoma.

Having said so much, is it better to smoke or not smoke this kind of cigarette with filter? In fact, whether it is a cigarette with a filter or not, it will harm your health. Quitting smoking is the right way. As I said before, it is best not to smoke.

References:

1.MIN-AESONG, NEAL L.BENOWITZ, MICAHBERMAN, et al. Cigarette Filter Ventilation and its Relationship to Increasing Rates of Lung Adenocarcinoma[J]. Journal of the National Cancer Institute,2017,109(12):djx075. DOI:10.1093/jnci/djx075.

2.B'CHIR F, LAOUANI A, KSIBI S, et al. Cigarette filter and the incidence of lung adenocarcinoma among Tunisian population.[J]. Lung cancer: Journal of the International Association for the Study of Lung Cancer,2007,57(1):26-33.

3. Ni Jianbin. Study on the stability of cigarette draw resistance[D]. Shaanxi: Northwest Agriculture and Forestry University, 2008.

Author: Shanghai Fengxian District Central Hospital

Liu HongweiChief Physician