The causation model argues that smoking is a primary influence on future drug use, while the correlated liabilities model argues that smoking and other drug use are predicated on genetic or environmental factors. One study published by the NIH found that tobacco use may be linked to cocaine addiction and marijuana use. The study stated that 90% of adults who used cocaine had smoked cigarettes before (this was for people ages 18–34). This study could support the gateway drug theory. Cessation
Smoking cessation, referred to as "quitting", is the action leading towards abstinence of tobacco smoking. Methods of "quitting" include advice from physicians or social workers, cold turkey, nicotine replacement therapy, contingent vouchers, antidepressants, hypnosis, self-help (mindfulness meditation), and support groups. A meta-analysis from 2018, conducted on 61 RCT, showed that one year after people quit smoking with the assistance of first‐line smoking cessation medications (and some behavioral help), only a little under 20% of smokers remained sustained abstinence.In the United States, about 70% of smokers would like to quit smoking, and 50% report having made an attempt to do so in the past year. In recent years, especially in Canada and the United Kingdom, many smokers have switched to use electronic cigarettes in order to quit smoking tobacco. See also
Cannabis smoking
Cigarette smoking among college students
Cigarette smoking for weight loss
Electronic cigarette
Herbal cigarette
List of cigarette smoke carcinogens
Snuff (tobacco)
Smokers paradox
Tobacco advertising
Tobacco control

References
Bibliography


== External links ==
According to one study, based on modeled concentrations, pre-Anthropocene tissue-bound levels in fish may not have differed markedly from current levels. However, based on a comprehensive set of global measurements, the ocean contains about 60,000 to 80,000 tons of mercury from pollution, and mercury levels in the upper ocean have tripled since the beginning of the industrial revolution. Higher mercury levels in shallower ocean waters could increase the amount of the toxicant accumulating in food fish, exposing people to a greater risk of mercury poisoning. See also
Canadian Reference Materials include some with methylmercury, e.g. DORM
Dimethylmercury, mercury with a second methyl group
Ethylmercury, a related cation
Mercury poisoning
Mercury regulation in the United States

References
External links
ATSDR - ToxFAQs: Mercury
ATSDR - Public Health Statement: Mercury
ATSDR - ALERT! Patterns of Metallic Mercury Exposure, 6/26/97
ATSDR - MMG: Mercury
ATSDR - Toxicological Profile: Mercury
National Pollutant Inventory - Mercury and compounds Fact Sheet
Methylmercury-in-fish exposure calculator provided by GotMercury.Org, which uses FDA mercury data with the EPAs calculated safe exposure levels. Methylmercury Contamination in Fish and Shellfish Archived 2013-11-02 at the Wayback Machine
nytimes.com, Tuna Fish Stories: The Candidates Spin the Sushi
U.S. Environmental Protection Agencys mercury site
U.S. Geological Surveys mercury site Archived 2013-11-02 at the Wayback Machine
Environment Canadas mercury site
Health Canadas mercury site
International Conference on Mercury as a Global Pollutant 2006-Madison, WI USA  2009-Guizhou, China  2011-Halifax, NS Canada