Thoughts from a Lab Rat

Many studies which have a smoking restriction test for cotinine which is metabolite or by-product of nicotine. Cotinine has a half-life of about 24 hours depending on the amount of cigarettes or cigars smoked. For most people, cotinine can be detected for up to a week after cessation of smoking.

The big concern for healthy subjects who do not smoke should be passive exposure or second-hand smoke. Maybe you live with someone who smokes or you work part-time in a bar where smoking is permitted. By being exposed to second-hand smoke, you are not only putting your health at risk, you are increasing your chances of having a positive cotinine test. Yes, you don’t actually have to smoke cigarettes to test positive! A marginal reading is typically acceptable though depending on the assay method used to test, it may still lead to a disqualification. Levels of 10 ng/mL to 100 ng/mL are generally associated with light smokers and passive exposure or second-hand smoke. Anything higher than 100 ng/mL would be considered an active smoker.

There are two types of second-hand smoke, sidestream and mainstream. Sidestream is the smoke that is emitted from a lit cigarette. Studies have shown that up to 80% of the smoke in the air is from sidestream which makes this type of secondhand smoke more dangerous. Mainstream smoke is the smoke exhaled from the smoker. Exposure to second-hand smoke can thicken the blood by increasing the production of red blood cells. This can lead to clotting and strokes which can lead to heart disease and cancer. Second-hand smoke can also cause increased blood-pressure.

How much second-hand smoke exposure to be harmful is unclear but any prolong periods of exposure is putting you at risk. If you live with a smoker, then you should definitely be concerned. Ask them to smoke outside. I have heard reports of people who live with smokers and have failed a cotinine test. If you are staying in a hotel, make sure you get a non-smoking room. Just because there isn’t someone smoking in front of you doesn’t mean that being in an environment that has been smoked in is any better. I occasionally am exposed to second-hand smoke and I usually end of gagging and covering my mouth with my shirt. Since I rely on studies for my income, I have always been weary of my exposure to second-hand smoke but after doing some further research, I will try to avoid it at all costs.

http://en.wikipedia.org/wiki/Second-hand_smoke

http://health.howstuffworks.com/understanding-secondhand-smoke-ga.htm