I cut and pasted this for you from a health web site. Question was how long does nicotine take to leave your blood stream. Here is the answer** nicotine is metabolized into cotinine, which then admixes with blood. Liver detoxification then takes place, facilitating removal of toxins from the blood. This process is slow in comparison to the removal of waste products by the kidney in form of urine, which takes place at a faster rate.
In these blood tests, nicotine is visible usually 1 to 3 days after last use of a nicotine-containing product, such as cigarettes, smokeless tobacco (snuff), and nicotine patches or gum. This may also vary in lieu of the amount of nicotine use, and the individual’s health and age.
On the other hand, when cotinine levels are used for determination, it may take 1 to 10 days until the levels will be undetectable in the blood.
However, a number of reasons can lead to false positive results of nicotine in the blood. These include working at metal refining areas where high levels of thiocyanate present, consumption of thiocyanate containing foods like cabbage, broccoli, almonds and mustards, and intake of medications such as amphetamines. Laboratory errors should also be considered.