Cigarette filters are intended to reduce the amount of smoke, tar, and fine particles inhaled during the combustion of a cigarette, but have no actual proven health benefits. Filters also reduce the harshness of the smoke and keep tobacco flakes out of the smoker's mouth.
In 1925, inventor Boris Aivaz patented the process of making a cigarette filter from crepe paper, with some variants including cellulose wadding, during experiments at the Ortmann plant of Bunzl. Aivaz produced the first cigarette filter from 1927 in co-operation with Bunzl's Filtronic subsidiary, but uptake was low due to a lack of the machinery required to produce cigarettes with the filtered tip.
From 1935, a British company began to develop a machine that made cigarettes incorporating the tipped filter. It was considered a speciality item until 1954, when manufacturers introduced the machine more broadly, following a spate of speculative announcements from doctors and researchers concerning a possible link between lung diseases and smoking. Since filtered cigarettes were considered "safer", by the 1960s, they dominated the market.
With classic filter cigarettes, the filter is covered with a cork-colored mouthpiece. Some cigarette brands use a white mouthpiece.
Most factory-made cigarettes are equipped with a filter; those who roll their own can buy them from a tobacconist or make them themselves.
The raw material for the manufacture of cigarette filters is cellulose (obtained from wood). The cellulose is acetylated (i.e. making it into a material called cellulose acetate or simply "acetate" for short), dissolved, and spun as continuous synthetic fibers arranged into a bundle called tow. The cellulose is a substituted diacetate (actually 2.35 - 2.55 substitution range) cellulose, due to its chemical and physical processing. This tow is opened, plasticized, shaped, and cut to length to act as a filter.
In the early 1950s, Kent brand cigarettes used crocidolite asbestos as part of the (Micronite) filter. Asbestos fiber is heatproof, insoluble and forms extremely fine fibers — but has been proven to cause lung cancer when inhaled. Other filter variations include Lark, Tareyton, Parliament, and Napoli cigarettes, which feature a chamber filled with activated charcoal granules.
The U.S. Department of Agriculture price support for the various grades of tobacco favored the use of #4 and 5 grade, which included what were known as sand lugs and floor sweepings at 10 cents/lb versus #1 grade at close to 70 cents. During the 1940s, it was less expensive to manufacture a filtered cigarette than a regular one.
In light cigarettes and some full flavor cigarettes, the filter is perforated with tiny holes that dilute the smoke with air. As such, the inhaled smoke contains less tar and nicotine. In theory, this should make the cigarette "safer" than full flavor ones. In practice, however, the average smoker compensates by inhaling more deeply or by covering parts of the holes with fingers or lips. Because of this, smokers of light cigarettes can be exposed to equal or greater doses of carcinogens and tar than they would be with medium tar cigarettes.
Most cigarette filters are made from cellulose acetate. Cigarette filters contain twelve thousand plastic-based fibers, and like many other forms of plastic are not biodegradable. The leftover filter is the most common form of litter; International Coastal Cleanup volunteers collect an estimated 53 million cigarette butts each year. The filters' non-biodegradability increases landfill demands, adds costs to municipalities' waste-disposal programs, and creates environmental blight in public spaces. Using standard tests adopted by the U.S. Environmental Protection Agency, Novotny and other researchers discovered that a cigarette butt soaked in a liter of water for four days will kill both the topsmelt and the freshwater fathead minnow fish species.
This resistance to biodegrading is a factor in littering, environmental damage and suggested lung damage. In the 2006 International Coastal Cleanup, the number of individual cigarettes and cigarette butts collected amounted to 24.7% of the total number of garbage items collected, over twice as many items as any other category.
Cigarette filters are the most common form of litter in the world, as approximately 5.6 trillon cigarettes are smoked every year worldwide. Of those it is estimated that 4.5 trillion cigarette filters become litter every year. In the 2006 International Coastal Cleanup, cigarettes and cigarette butts constituted 24.7 percent of the total collected pieces of garbage, over twice as many as any other category. One study showed that for the LC50 of both Marine Topsmelt (Atherinops affinis) and freshwater Fathead minnow (Pimephales promelas) smoked cigarette filters + tobacco are more toxic than smoked cigarette filters, but both are severely more toxic than unsmoked cigarette filters.
The first step in the biodegradation of cellulose acetate is the deactylation of the acetate from the polymer. The second reaction Acetylesterase is a catalyzes. The duration of the biodegradation process occurs over month to years, the major factor being the availability of the appropriate enzymes. Another process of degradation is Photodegradation.
Remediation and regulation efforts
Many governments have sanctioned stiff penalties for littering of cigarette filters; for example the Washington state imposes a penalty of $1,025 for littering cigarette filters. Another option is developing better biodegradable filters, much of this work lies heavily on the research in the secoundary mechanism for photodegradtion as stated above. The next option is using cigarette packs with a compartment to discard cigarette butts in, implementing monetary deposits on filters, increasing the availability of butt receptacles, and expanding public education. It may even be possible to ban the sale of filtered cigarettes altogether on the basis of their adverse environmental impact. Recent research has been put into finding ways to utilizes the filter waste, to develop a desired product. One research group in South Korea have developed a simple one-step process that converts the cellulose acetate in discarded cigarette filters into a high-performing material that could be integrated into computers, handheld devices, electrical vehicle and wind turbines to store energy. These materials have demonstrated superior performance as compared to commercially available carbon, graphene and carbon nano tubes. The product is showing high promise as a green alternative for the waste problem. Another group of researchers has proposed adding tablets of food grade acid inside the filters. Once wet enough the tablets will release acid that accelerates degradation to around two weeks.
- Cigarette holder
- List of cigarette smoke constituents
- List of additives in cigarettes
- Tobacco smoking
- "Consumers' knowledge and beliefs about the safety of cigarette filters - HASTRUP et al. 10 (1): 84 - Tobacco Control". Tobaccocontrol.bmj.com. 1970-04-14. Retrieved 2013-01-02.
- "The History of Filters". tobaccoasia.com. Retrieved 2008-05-18.
- "British American Tobacco - Cigarettes". Bat.com. Retrieved 2013-01-02.
- "What are cigarettes and filters made of? - Longwood University". Longwood.edu. Retrieved 2013-01-02.
- Snopes.com: "Cigarette Filter Danger"
- http://www.youtube.com/watch?v=Qej0nLJBywc%7C 1966 Lark cigarette commercial
- Rigotti NA, Tindle HA (March 2004). "The fallacy of "light" cigarettes". BMJ 328 (7440): E278–9. doi:10.1136/bmj.328.7440.E278. PMC 2901853. PMID 15016715.
- Louis R. Carlozo (June 18, 2008). "Kicking butts: How the butts stack up". Chicago Tribune.
10-15 years: length of time it takes a filter's component fibers to break down; they do not biodegrade
- http://www.universityofcalifornia.edu/news/article/30004[dead link]
- Ceredigion County Council[dead link]
- Register KM (August 2000). "Cigarette Butts as Litter—Toxic as Well as Ugly". Underwater Naturalist, Bulletin of the American Littoral Society 25 (2).
- Pauly JL, Mepani AB, Lesses JD, Cummings KM, Streck RJ (March 2002). "Cigarettes with defective filters marketed for 40 years: what Philip Morris never told smokers". Tob Control 11 (Suppl 1): I51–61. doi:10.1136/tc.11.suppl_1.i51. PMC 1766058. PMID 11893815.
- International Coastal Cleanup 2006 Report, page 8[dead link]
- Novotny TE, Lum K, Smith E, et al. (2009). "Cigarettes butts and the case for an environmental policy on hazardous cigarette waste". International Journal of Environmental Research and Public Health 6: 1691–705.
- "The world litters 4.5 trillion cigarette butts a year. Can we stop this?". The Houston Chronicle. Retrieved 2014-09-16.
- "International Coastal Cleanup 2006 Report, page 8". Retrieved 2009-11-13.
- Sluaghter E, Gersberg RM, Watanabe K, Rudolph J, Stransky C, Novotny TE (2011). "Toxicity of cigarette butts, and their chemical components, to marine and freshwater fish". Tobacco Control 20: 25–29.
- "Acetylesterase-mediated deacetylation of pectin impairs cell elongation, pollen germination, and plant reproduction". American Society of Plant Biologists. 2012-01. Retrieved 2014-10-03. Check date values in:
- Hon NS (1977). "Photodegradation of Cellulose Acetate Fibers". Journal of Polymer Science Part A: Polymer Chemistry 15: 725–744.
- Hosono K, Kanazawa A, Mori H, Endo T (2007). "Photodegradation of Cellulose Acetate flim in the presence of bensophenone as a photosensitizer". Journal of Applied Polymer Science 105: 3235–3239.
- "Accidents, fires: Price of littering goes beyond fines". Washington: State of Washington Department of Ecology. 2004-06-01.
- "Cigarette Butts and the Case for an Environmental Policy on Hazardous Cigarette Waste". Retrieved 2009-09-21.
- Minzae L, Gil-Pyo K, Hyeon DS, Soomin P, Jongheop Y (2014). "Preparation of energy storage material derived from a used cigarette filter for a supercapacitor electrode". IOP Science 25: 34.
- . Environmental Health News. 2012-07-14 http://www.environmentalhealthnews.org/ehs/newscience/2012/06/2012-0725-biodegradable-cigarette-filters. Missing or empty
- How stuff works: Cigarette filters
- Article on Tobacco Control website on the "defective design" of cigarette filters ("Essentially, this journal offers a one-stop shopping guide for anti-smoking literature and other resources." - Philip Morris 1992.)
- PBS's NOVA Search for a Safer Cigarette
- UCSF Tobacco Industry Videos Collection
- UCSF Tobacco Industry Audio Recordings Collection www.filterspakistan.com