A Certified Spiking Solution® suitable for use in nicotine testing, environmental monitoring, or clinical and diagnostic testing of nicotine biomarkers by LC-MS/MS or GC/MS. Also known as nicotine-derived nitrosamine ketone, NNK is a potent carcinogen and biomarker of exposure to cigarette smoke. NNK, produced upon the curing of tobacco, is found in a variety of tobacco products including chewing tobacco, snuff, cigarettes, and cigars.