Objective:
To prepare for the Olympic Games at Tokyo 2020, smoking areas in Tokyo are getting smaller. However, tobacco vaporizers are not managed like other tobacco products. To clarify reasons why tobacco vaporizers are managed differently from other tobacco products.

Methods:
Several kinds of information of tobacco vaporizers were collected from newspapers, internet and so forth.

Results:
Tobacco vaporizers are a kind of e-cigarettes. Three vaporizers are available in Japan. They are IQOS, ploomTECH and glo. Most popular one is IQOS. By the reports of Japanese Ministry of Health, Welfare and Labor, tobacco vaporizers provide almost same value of nicotine and smaller values of carcinogens in their mainstream smoke. The nicotine density in room by tobacco vaporizers is smaller than that by cigarettes. Epidemiological data are not enough for evaluate their negative health effects. Tobacco companies advertise they have less harm on health than cigarettes. Some restaurants permit to use only ploomTECH in their private rooms because of low bad smell. Some smoking areas are only for tobacco vaporizers because of low value of nicotine, carcinogen and bad smell around users.

Conclusions:
Biggest reason not to manage tobacco vaporizers like cigarettes is that only small scientific data are available to evaluate their negative health effects. They are evaluated by their less bad smell or low values of carcinogens in present status. But the vapor of them contains tars and other harmful materials like cigarettes. Scientific data of tobacco vaporizers should be collected urgently. Scientific data of tobacco vaporizers should be collected urgently. To diffuse facts of the vaporizers is necessary and regulations should be made by the precautional principles.