Nicotine can be measured in your blood and saliva, but because cotinine has a longer half-life, testing for cotinine is typically preferred.Īccording to 2016 research, the half-life of cotinine is the same whether tested for in your blood plasma, urine, or saliva.

How long will traces of nicotine be present in your blood and saliva? People with heavy exposure to secondhand smoke may test at levels between 1 and 10 ng/mL.

People who smoke but go 2 weeks without nicotine exposure before testing may show urine cotinine levels of less than 50 ng/mL.Įach lab may have different reference ranges for positivity, so it’s important to discuss the results with a doctor or technician. If you’re a current smoker, the test show urine cotinine levels of 1,000 to 8,000 nanograms per milliliter (ng/mL). Genetic differences can also affect the amount of time cotinine is detectable in your body.Īccording to research summarized by the CDC, non-Hispanic Black Americans may metabolize cotinine more slowly than non-Hispanic white Americans.Ī positive urine test can depend on when you provide a urine sample relative to the last time you ingested nicotine. However, the way each person’s body metabolizes nicotine to create cotinine is different. However, tests for this metabolite can detect cotinine even after it has reached this point.Ĭoncentrations of cotinine in urine are about 4 to 6 times higher than in blood plasma or saliva.Ī 2019 study used cotinine urine tests on people preparing for bariatric surgery to determine adherence to pre-surgery instructions.Īccording to the study’s authors, the cotinine urine test provided high sensitivity and specificity for smoking in at least the previous 72 hours.Īnother study from 2020 found that cotinine may still be detectable in urine for at least 8 weeks. However, it may be as long as 40 hours, according to a 2016 research review.Ī half-life refers to the number of hours before half of the cotinine will have left your system. How long will traces of nicotine be present in your urine?Ĭotinine has a half-life of about 16 hours, according to the Centers for Disease Control and Prevention (CDC).

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