If you are around people that smoke and inhale the second hand smoke, you will test positive. My sister almost lost her insurance coverage because her husband smoked in their home and she was breathing all of that in. When she went for her physical the Dr. Asked her if she had started smoking because he found nicotine in her blood sample. She had to have proof that she didn't smoke to keep from losing the insurance...and now her husband only smokes outside!!
Just check this page out. I did not believe it at first then I read a little more. Www.noarthritis.com/NicotineVegetables.htm
I have not smoked in 60 days and cotinine still comes up in my blood work what can it be?