Tag: Biomarker

While tobacco plants contain small amounts of cotinine, up to 80% of the cotinine found in a tobacco user's body is produced by the liver after exposure to nicotine. This fact reveals the key difference behind the question: **is cotinine present in cigarettes?** The answer is that cotinine is a byproduct of nicotine metabolism, and its presence is a marker of tobacco use, not a primary ingredient in cigarettes.

Cotinine, a major metabolite of nicotine, has a half-life of about 20 hours in the body, which is significantly longer than nicotine's few hours. This stability makes it an excellent biomarker for detecting tobacco use or secondhand smoke exposure. However, many health risks and side effects are mistakenly attributed to cotinine itself rather than the underlying nicotine exposure it indicates.