E-(electronic) cigarette

History

The earliest electronic cigarette can be traced to Herbert A. Gilbert, who in 1963 patented a device described as “a smokeless non-tobacco cigarette” that involved “replacing burning tobacco and paper with heated, moist, flavored air.” This device heated the nicotine solution and produced steam. In 1967, Gilbert was approached by several companies interested in manufacturing it, but it was never commercialized and disappeared from the public record after 1967.

Hon Lik, a Chines pharmacist, is widely credited with the invention of the first generation electronic cigarette. In 2000, he came up with the idea of using a piezoelectric ultrasound-emitting element to vaporise a pressurized jet of liquid containing nicotine diluted in a propylene glycol solution. This design produces a smoke-like vapour that can be inhaled and provides a vehicle for nicotine delivery into the bloodstream via the lungs. He also proposed using propylene glycol to dilute nicotine and placing it in a disposable plastic cartridge which serves as a liquid reservoir and mouthpiece.

The device was first introduced to the Chinese domestic market in May 2004 as an aid for smoking cessation and replacement. The company that Hon Lik worked for, Golden Dragon Holdings, changed its name to Ruyan (iterally “Resembling smoking”), and started exporting its products in 2005–2006 before receiving its first international patent in 2007.Several e-cigarette models marketed by tobacco companies were launched or are set to launch in 2013, including the Vuse, MarkTen, and Vype. Blu, a prominent e-cigarette producer, was also acquired by a tobacco industry leader in 2012.

An electronic cigarette (or e-cigarette), personal vaporizer (PV), or electronic nicotine delivery system (ENDS) is an electronic inhaler meant to simulate and substitute for tobacco smoking. It generally utilizes a heating element that vaporizes a liquid solution. Some release nicotine, while some merely release flavored vapor. They are often designed to mimic traditional smoking implements, such as cigarettes or cigars, in their use and/or appearance. The benefits and risks of electronic cigarette use are, as of 2013, uncertain, but they are likely safer than smoking tobacco. Laws vary widely concerning their use and sale, and are the subject of pending legislation and ongoing debate.

Smoking cessation

The World Health Organization states that as of July 2013, no rigorous studies have been conducted to determine if electronic cigarettes are a useful method for helping people to stop smoking.The British Medical Association states that there is emerging evidence of smoking cessation benefits, but has concerns that they are subject to less regulation than conventional nicotine replacement therapy, and that there is no peer-reviewed evidence of their safety or efficacy. They recommend a “strong regulatory framework” for e-cigarette distribution in order to ensure their safety, quality, and that their marketing and sales are restricted to adults. The BMA encourages health professionals to recommend conventional nicotine replacement therapies, but for patients unwilling to use or continue those methods, they say health professionals may present e-cigarettes as a lower-risk option than tobacco smoking.A 2011 review published in the Journal of Public Health Policy states that electronic cigarettes may aid in smoking cessation and are likely to be more effective at this than traditional pharmacotherapy. The American Association of Public Health Physicians (AAPHP) view electronic cigarettes as similar to other nicotine replacement therapy and recommend them as a harm reduction method for those who have failed to quit by other means. In one study, 31% of users had ceased smoking six months after beginning use of electronic cigarettes and a further two-thirds had reduced their tobacco consumption.

Toxicity

Electronic cigarettes should theoretically have fewer toxic effects than traditional cigarettes. Nevertheless, concrete evidence is insufficient as of 2013, although tentative evidence suggests they are safer than real cigarettes, and possibly as safe as other nicotine replacement products. The electronic systems appear to generally deliver less nicotine than smoking. The amount of nicotine delivered is believed to vary between different brands of electronic cigarettes.

A preliminary analysis of e-cigarette cartridges by the FDA identified that some contain tobacco-specific nitrosamines, known cancer-causing agents The FDA’s analysis also detected diethylene glycol, a poisonous and hygroscopic liquid, in one of the cartridges manufactured by Smoking Everywhere and nicotine in some cartridges claimed to be nicotine-free. Further concerns were raised over inconsistent amounts of nicotine delivered when drawing on the device. In some e-cigarettes, “Tobacco-specific impurities suspected of being harmful to humans – anabasine, myosmine, and ß-nicotyrine – were detected in a majority of the samples tested.” It is not clear if these chemicals were detectable in exhaled vapour.The UK National Health Service noted that the toxic chemicals found by the FDA were at levels one-thousandth that of cigarette smoke, and that while there is no certainty that these small traces are harmless, initial test results are reassuring.

Most electronic cigarettes take an overall cylindrical shape. Common components include liquid, a cartridge, an atomizer, and power source.Many electronic cigarettes are composed of streamlined replaceable parts, while disposable devices combine all components into a single part that is discarded when its liquid is depleted.

• Cartridge: The cartridge generally serves as both a liquid reservoir and mouthpiece (though some devices have separate mouthpieces). It is designed to allow the passage of liquid into the atomizer, and vapour from the atomizer to the user’s mouth. Some models employ a tank that holds loose fluid, while some use a foam material to hold liquid in place. When liquid is depleted, users can refill the cartridge or replace it with another ready-filled cartridge.

• Atomizer: The atomizer is the central component. It generally consists of a small heating element responsible for vaporizing liquid, as well as a wicking material that draws liquid in. “Dripping” atomisers forgo a fluid reservoir, instead requiring periodic manual moistening of the wick.

• Cartomizer: Since atomizers tend to lose efficiency over time due to a buildup of sediment, or “burn out” entirely, some models employ a disposable “customizer” component that also doubles as the device’s cartridge. The piece consists of a heating element surrounded by a liquid-soaked poly-foam.

• Power: Most portable devices contain a rechargeable battery, which tends to be the largest component of an electronic cigarette. The battery may contain an electronic airflow sensor whereby activation is triggered simply by drawing breath through the device, while other models employ a power button that must be held during operation. An LED to indicate activation may also be employed. Some manufacturers also offer a cigarette pack-shaped portable charging case (PCC), which contains a larger battery capable of charging e-cigarettes. Devices aimed at enthusiasts may sport additional features, such as variable power output and support of a wide range of internal batteries and atomizers.

Liquid

Liquid for producing vapor in electronic cigarettes, commonly known as e-juice or e-liquid, is a solution of propylene glycol, vegetable glycerin (VG), and/or polyethylene glycol 400 mixed with concentrated flavors; and optionally, a variable concentration of nicotine. The solution is often sold in a bottle or in pre-filled disposable cartridges. They are manufactured with various tobacco, fruit, and other flavors, as well as variable nicotine concentrations (including nicotine-free versions). The standard notation “mg/ml” is often used in labeling for denoting nicotine concentration, and is sometimes shortened to a simple “mg”

Usage

Electronic cigarette sales increased from 50,000 in 2008 to 3.5 million in 2012.^[As of 2011, in the United States, one in five adults who smoke have tried electronic cigarettes. In the UK 11% of regular smokers were using electronic cigarettes in 2013 and 24% had used them in the past. 1% of non-smokers had tried them and 0% were currently using them.Among grade 6 to 12 students in the United States, those who have ever used the product increased from 3.3% in 2011 to 6.8% in 2012.10% of students who have used e-cigs have never smoked. A 2013 UK survey by Action on Smoking and Health found that among non-smokers under 18, 1% reported having tried e-cigarettes “once or twice,” 0% reported continuing use, and 0% intended to try them in the future. ASH concluded that among children who have heard of e-cigarettes, sustained use is rare and confined to children who smoke or have smoked.

SMOKING IS VERY BAD FOR HEATH.ITS INCREASE THE RISK OF CANCER OF HUMAN BODY.