in water) and a vaporization chamber, which produce an aerosol that simulates the smoke of a cigarette ( fig. 1 ).Nicotine and other additives like flavorings and glycerol (purified vegetable glycerine) may be added in various concentrations to the liquid. No combustion is involved in the process and the 'smoke' produced is an aerosol of liquid particles, a 'mist' [1] .Advertised as a valid way to quit smoking real cigarettes, the e-cigarette has been the subject of much controversy but little experimental study. This review provides a brief overview of the current evidence on the ecigarette. Aerosol GenerationBesides water, the main ingredient of the e-liquid is usually propylene glycol (PG) in water. A mechanical sensor detects when the user inhales and it then triggers the microchip controlling the heater which raises the temperature in the vaporization chamber.As specified by the manufacturers, the temperatures in the vaporization chamber range from 40 to 65 ° C [1] . Recently, however, variable voltage devices gained popularity as they can increase the temperature of operation and the heater surface area in order to tune the vapor to the user's satisfaction. No reliable data could be found on the range of temperatures in these recent devices. The same uncertainty exists about the operating temperature in Key WordsElectronic cigarettes · Propylene glycol · Nicotine AbstractMarketed since 2004 as an alternative to nicotine delivery and advertised as a valid means to smoking cessation, the electronic (e)-cigarette has been the subject of much controversy but very little experimental study. This review provides a brief summary of the current knowledge of this product. Propylene glycol and glycerol, the main ingredients of the fluid that is vaporized, have proved to be harmless in the fog machines of the entertainment industry. However, in the case of the e-cigarette fluid, the composition is not properly labeled: additives like nicotine and flavors vary between and within brands and contamination with various chemicals has been detected. The short-term toxicity seems low, but the long-term toxicity is unknown. The usefulness of the e-cigarette in smoking cessation has still to be clinically established.

We carried out a maximum expiratory flow-volume curve (MEFV) and a spirometric recording with 67 athletes of different ages (15-27 years) and disciplines (rowers, kayakists, cyclists, swimmers) and with 20 adult and 13 adolescent nonathletic controls of matching ages. These recordings were repeated, with athletes only, after 6-10 months of training. Significant differences between the groups of adult athletes and the controls were observed for some parameters, the most discriminating of which were, in order, the peak expiratory flow (PEF), the forced expiratory volume in the first second (FEV1), and the flow at 75% of the vital capacity (V75). The vital capacity (VC) itself was only higher in the rowers group. The adult athletes, when grouped together (n = 47), produced a higher flow at 50% of their VC (V50) than the control group (+15%, P less than 0.05) with no difference in the flow at 25% of VC (V25) nor in the VC. A study of the effects of training showed no evolution among high level athletes while increases of 14% of the PEF, 5% of the V75, and 7% of the FEV1 were found after 7-10 months of training in adolescents; the VC increased during that time by only 2.7%. The reproducibility of these ventilatory parameters after 6-8 months was studied with adult athletes. The upper limit of the variation (95% CLl) was 12% for the FEV1 and forced vital capacity (FVC), 18% for PEF, 21% for V75 and V50, and 40% for V25.(ABSTRACT TRUNCATED AT 250 WORDS)