Its generally accepted that for every cigarette you smoke, the actual nicotine absorption is around 1-2 mg of nicotine per cigarette

A 2015 paper published in the scholarly journal Substance Use and Misuse found that a recent review of 42 empirical papers on addiction treatment programs for multiple substances from 1989 through 2005 found that the prevalence of tobacco use among persons in recovery ranged between 65% and 87.2%. Compare that to the fact that in 2012, only 18.1% of adults in the general population reported smoking cigarettes, and you understand why individuals in treatment for, or recovery from, alcohol and substance use disorders are one group that continues to use tobacco (cigarette smoking) at rates that concern health practitioners. Those numbers vary according to other studies one reported on in 2015 by Forbes concluded that the overall rate of smoking among addicts in treatment for drug and alcohol use was 84%, compared with a rate of 31% for individuals of the general public but the findings are the same: Addicts and alcoholics, in treatment and in recovery, smoke

Ribeiro VV, Lopes TC, dos Amaral Santos Pinto M, Pvoa AA, Corra VR, De-la-Torre GE, Dobaradaran S, Green DS, Szklo AS, Castro B (2022) Cigarette butts in two urban areas from Brazil: links among environmental impacts, demography and market
Even people who smoke less than five cigarettes a day can have early symptoms of cardiovascular disease
Retrieved November 11, 2012
Research conducted on cigarettes smoked from 1998 to 2012 showed a significant increase in the amount of nicotine present per cigarette from 1.65 milligrams to 1.85 milligrams[xvi]